Hey guys i wanted to update you all on the progess ive had so far, first i have been on vacation for the past two weeks so i havent had time to do anything, but as soon as i got back i got started. I have managed to put the 3.5" jbl gtos in the front wired in.
I have rewired the 6.5" speakers and installed them ready for the amp in the trunk. and thursday (i decided to go with a new deck) a kenwood excelon is coming in.
Tomorrow i plan on putting the equalizer in and finish running amp wires, i got the RCAS to do and the remote turn ons as well as hiding the power wires. Now the question is, i got a 4 gauge wire for the amp to power the subs.
I was hoping to put in two 12" subwoofers into the trunk, (i knwo im very hard headed i liek things in pairs lol) I was thinking about some Alpine SWR-1242D - Alpine 12" Type R 1500W Dual 4 Ohm Subwoofer or maybe go ahead and go with the JBLs for a complete JBL setup.
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3148 or http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3166
but at the same time i was hoping for yuor input on the matter, and if you know of a better idea for the setup i have id like the input.
Also could you match me a good class d mono amp for the perfect setup? i appreciate any input you have and will respond to any questions, thanks again
Zach
Replies (29)
SQLThump on 06/24/2008 12:01:43
Perfect setup??? No such thing. It all depends on what subs you end up using in the end. The JBL P1222 is a beast, yes, but bit power hungry and will require a beast of an amp. Those GTO's are a bit dated now, and JBL is doing bigger and better things with their subs siince those GTO's.
Check out the JBL GT5-12's. They are more efficeint, require less power, and with a ported enclosure, make some mean bass with little amplification. A great amp to go with these would something making 400-600RMS at two ohms.
Also, did you say you are putting 6.5's in the trunk or did I read that wrong? I sure hope I read that wrong.........
Zach1989 on 06/24/2008 12:04:02
Yea i typed it in a little confusing the 6.5"s are in the car but i wired them into the trunk because the amp im using to power them is 50 watts rms X 2 and they have a rating of 60 rms each. i probably should clarified.
Also what about infinity's? But let me check out the Jbls first actually.............................
SQLThump on 06/24/2008 14:24:44
None of the Infinity lineups will really trounce anything JBL makes. Why you ask? Because they are made by the same parent company, Harmon International, otherwise known as Harmon Kardon. They make pretty great stuff all around, and have found little differences aside from looks when dealing with their products of comparable price/power range.
Glad to hear you have the 6.5s in the car. Good choice of amp power as well. I am sure they will hold up well. Also, the whole of the car audio world thanks you for losing the Dual H/U. Take it out for target practice, or have somebody run it over with an 18-wheeler. The Kenwood will serve you much better, and for longer than 3 months!GRIN
swez on 06/24/2008 14:58:08
If we look at the history of Harmon, they have 2 main audio/speaker systems in the mix. Infinity was designed for HT use and then adapted to mobile audio. JBL was primarily Pro/Commercial/Home Audio gear and has been adapted to mobile markets now too. The net affect, they are both hybrids for mobile audio and lots of speaker design experience on both sides of the table. To be sure, they share technology ideas and compete for market share as well. That's a good strategy for Harmon and the consumer.
In your case, it seems like JBL is the main contender. The P1222D woofers are "very efficient", can take plenty of power and don't require huge boxes to make them sound great. They are rated at 400 RMS per each, but that does not mean they won't perform well with a smaller amp too. Here, the ideal amp will be 2 ohm stable and deliver 500-800 Wrms @ 2 ohms. The trick is to use a bass amp that is Class D, and does not stress the electrical system of this car beyond limits that demand expensive electrical upgrades. (H.O. ALT and extra BAT's)
Think about that a while before you proceed,
Swez
Zach1989 on 06/25/2008 02:18:55
I just put in a brand new ALT. and i was thinking about getting one of the yellow top deep cycle batteries for a little added protection, as for the JBL's thats pretty much what i was thinking about sticking to. A lot of people said good things and they seem to be pretty good speakers.
Based on my sitution would it be better for me to get the P1222D's or the GT5-12? I believe that my ALT. is pretty strong but it also has a lot of power already being used by other parts of the vehicle.
Correct me if im wrong but, in order to get an "amp rating" you take the rms power you will be using and divide it by the output voltage to get the amount of amps i should be using?
In this case i have an 80 amp ALT and if i am correct again about 60 Amps are already being used, so i wasnt sure if taking two gt5-12's and putting them in a ported box would be a more efficient way to get bass without a huge tax on my system, or would it work out just fine with two P1222D's?
swez on 06/25/2008 04:39:31
Let's fill in a few blanks before you choose anything more than what's on the table.
A stock 80A ALT will only produce max output above ~2300 RPM. At idle speeds, the output is about half of that. One can reduce the pully diameter on the ALT to increase the idle speed rotation and get more output from the ALT. (Easy and low cost option)
Depending on all the electronics in this vehicle, it will operate fine at 30-40A's, just cruising along. The big drains come only when operating headlamps, fog/driving beams, blower motor, power seats/windows and rear window defogger circuits.
Now, when amplifiers are added, the power demand will change dramatically depending on volume level settings and how hard we push the bass engine. The most demanding scenario comes from pure test tones and sustained low bass notes at high SPL levels.
When listening to music, the RMS power levels change constantly with the music content. Rap and Hip Hop cuts have very high bass content and this is where amps, subs and electrical systems are put to the "daily driver" test. It's most noticable at night when we crank up the bass, have the headlights on and maybe running the Air Conditioner too.
At a stop light, the engine RPM is low and so is ALT output. Dial up the bass and the headlights will dim to some degree. (Big bass thumps)That's normal and to be expected. To prevent/limit that, we simply dial back on the HU volume or if the sub amp has a remote bass control, dial back and all is well. (Common sense right?)
OK, these are the basics of what you can expect. Adding a Optima Yellow Top can help. Especially if it has a high CCA rating. (Cold Cranking Amp rating of 750 or higher) This is considered a "buffer" in the power supply to the vehicle. When the ALT cannot produce enough current, the BAT makes up the difference for a short time. However, the BAT is now depleted to a degree and the ALT needs to recharge it to normal levels. That's the cycle of events we have to manage. (Got the picture?)
Confirm your understanding of this scenario and then we can move on to the next phase... sub/amp choices.
Swez
Zach1989 on 06/25/2008 05:33:42
Ok i Understand that, the yellow top i heard can take big drops, charges real quick, and also can run to just about nothing and still be stronger than a regular battery becaus eit is a deep cycle one, howver i did some research.
A very similair car to mine has the same mounting and whatnot i just need to change the pulleys this ALT has a rating of 115, which this would only cost me 100" to buy with no core charge i think that and the deep cycle would be a good combo, or no?
That should keep everything at a nice limit and still have at least 40 or 50 Amps to play with and the power coming to the 6.5"s out of the little amp is only like 8 amps (RMS/ 12), (has a 25 amp fuse) which 115 amps -- 70 amps = 45 amps which at that rate should give me about 500 or 600 watts rms at 12 volts battery charge to play with.
Is that correct in the mathematic or am i just totally in the wrong step? If I am correct then go ahead and well see the sub/amp choices that will work. Thanks Swez for the very quick and detailed assistance.
Ps. by the way i ran the rcas and almost have the remote turn ons to the head unit space and i will have them finished with wiring tomorrow and maybe the head unit and EQ if i have time.
swez on 06/25/2008 08:42:50
The Yellow Top is a "Deep Cycle" battery. It can take more than 300 complete discharges and still work fine. (Try that on a normal car battery and it's toast after only a handful of deep discharges) Good choice.
The 115A ALT is a good deal if new, out of the box and has a decent warranty. That's a very fair price. ($100.00)
Another thing to remember, amplifiers consume more power than they can put out the back end. Class D bass amps are about 80% eff. Class A/B full range amps are about 60% eff. We need to consider that when choosing the rated power of a given set of amplifiers.
When calculating power, we use Ohm's Law. Voltage sq/Resistance = Power in watts. We measure the AC voltage coming out of the amp to the speaker and run the equation to determine RMS watts the speaker is actually getting. Here's the deal:
Speaker is 2 ohms nominal
Voltage reading is 32 volts AC
Power in RMS watts: 32 x 32 = 1024/2 = 512 watts to sub(s)
Not a bad number huh? If this is a Class D amp, we can calculate the total power draw comsumed as well: 512/.8 = 640 watts consumed. We can also figure out how much actual current this amp draws since we know input voltage and wattage consumed. This would be a worst case scenario using long duration test tones. Normal music is not so severe.
Source voltage: 14.0 VDC (+/- 0.2 volts)
Watts consumed: 640
Amperage draw: 640/14 = 45.7A's
This is just scratching the surface Zach. The math is more complex than I am feeding you here. But it's close enough to get a feel for how amps/speakers work in car audio systems. Don't see a need to go much deeper for now. It'll just make your head spin.
When installing the EQ, it would be wise to tap the EQ REMote trigger and main power lines to the acc/ign line on your HU. The HU REM line is used to feed the amps only. Make sure to fuse the EQ main power line too. This will prevent over-loading the HU REMote power supply.
Good luck on your install steps. Just take your time, do it well and everything should come out noise free later. Just make sure your HU and EQ grounds are connected to bare metal grounds in the dash, floor panel or firewall. DO NOT USE THE FACTORY HARNESS GROUND! This should prevent or minimize ground loop noise later.
Swez
PS Am on vacation for now and have more time to help guys on CK. It feels good to be back on the board again and it's great to help others.
Zach1989 on 06/25/2008 15:37:52
Wow thats crazy, way more complex than i ever thought lol. So my plan of action will be then getting the yellow top and the ALT. So if i crank the amp up to 115 and im only using roughly 60, then what could be some good subs and amp combo we can use?
Might as well stick with JBL's since thats all i got in the car now and you mentioned before of their experience, any amp subs combos come to mind, like i said before im looking for two 12"s and an amp to match.
Ohhh and as for the wiring of the EQ and HU, my plan was right on with yours i have an inline fuse (20AMP ok?) and i was going to run the rem. turn on and the power to the HUs power supply and then run its own ground and the same goes to the HU, pretty much liek you said before.
I know a little bit about screwing up due to my last projects i was in a rush and wanted it to be done no matter the cost. Those times the cost was faulty equipment with horrible sound. I would be in there like everyday trying to fix the problem and whatever.
So now i decided im not gonna waste my money anymore, do it all the right way the first time, and get good quality subs amps speakers HU's EQS so that when the time comes it will perform and maintain performance.
Anyways, thanks again for the audio lesson im going to write that down and keep it, you never know when i can help someone or heck i might need it again as well.
swez on 06/26/2008 22:10:19
When fusing your HU/EQ, look at fuse rating on the HU and add a few more amperes for the EQ. If you do use a 20A fuse, use #12 gage line as the main feeder off it's own circuit so you don't blow any fuses in the fuse panel.
For this much current, it might be a good idea to use a relay too. Are you familiar with the workings of relays and how to install them properly? Have a look here for details:
http://www.bcae1.com/relays.htm
Swez
Zach1989 on 06/28/2008 13:33:12
Ok Ill do that, but ive never worked with relays or any relay type systems, im planning on installing everything tomorrow. well the wiring of it all together at least. then i have to see about mounting. But thats no problem little bit of modification itll look like it grew there.
But Ill look into those relays and let you know on progress hopefully if everything goes smoothly i should have the small amp hooked up along with the hu/eq and should hear what those jbls sound like.
Then im on to my last task and the most important one of all, lol, find a good amp / sub combo hopefully by the end of next weekend i can have everything all good and hear the finished product. itll be real nice.
swez on 06/28/2008 15:41:39
Just make sure you get the common Bosche type, 5 pin relay. (SPDT) They cost about $4 at any good autoparts store and rated between 20-40A's.
It's good to get the harness with pigtails so you can wire everything up with crimp connectors and hide it in the dash. Just follow the diagrams on the link above and it should come out good. If you need help, don't guess. Here's another site that covers relays in simple terms:
http://www.the12volt.com/relays/relays.asp
Swez
PS For this install, a diode shunt is not required.
Zach1989 on 06/29/2008 09:04:37
Alright thanks a bunch Swez. I have the HU wired and the EQ as well I figured it all out, on thing left to do is find a ground and mount it all. Then tune the amp and test everything out.
I am actually very excited to see how it sounds, I have done everything the right way the first time so there would be no mistakes, I have the 115 amp alternator on order and i will buy the yellow top battery after the ALT. is installed.
That means we have like i said about 40 -50 extra amps to play with for the amp and subs. So i guess that our next step.
swez on 06/29/2008 09:26:41
Did you install the relay as mentioned too or no?
Good progress so far and you can do a preliminary amp setting if you wish.
For now, use these settings as a guide:
Sub amp: Low Pass Filter set at ~80 Hz
Fullrange amp: High Pass Filter set at ~80 Hz
Gain setting on all amps: Set to middle point of adjustment range
Since the front stage is low power off the HU, you'll want to try and balance the rear speaker amp to compliment the front stage, but not over-power the fronts. Once you reach a nice balance point with amp gain settings, then it's time to bring up the sub to a level you prefer.
FYI: If this HU has crossover menu settings for the front channels, start at ~300-400 Hz w/ the HPF settings. This will keep unwanted bass from the 3.5" GTO's. If the HU has no menu settings, passive filters are needed, (Bass blockers) to do this for you.
Got all that?
Swez
Zach1989 on 06/29/2008 13:04:45
Here is the HU:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=6343
Wasn't sure what you meant about crossover menu settings so i thought maybe you might be able to tell, lol. Hooked everything up as planned but now the eq wont turn on.
It was working just fine then once i hooked the amp up it stopped working, i think i might have shorted something out. The HU works but the amp and EQ dont turn on, i wonder if maybe the remote turn on is what the problem.
Ill keep you posted though.
Zach1989 on 06/29/2008 14:48:30
Ok found the problem.... what was going on was the power ant. that i had the rem. turn ons hooked up to.....well when the radio is on so is the power ant. but when the cd is in the power ant. isnt on anymore.
So that being the case there is another connection on the HU, the PO. continuous so that is like a power ANT that stays on so i hooked it to that and were good. let me tell you it sounds GREAT for what it is. I think it was my best sounding install.
I thank you guys a lot for your help up to this point and we finally made it to the last step. I will definitely be donation again when i get my pay on thursday. This site has to stay up and running for everyone to share ideas and help. thanks again...
ohh my amp only has a gain and frequency knob.... and a bass flat or treble switch, so i set frequency at 80hz, gain up just past half way and the switch on flat, which turned out to be a bass and mid combo i think....
swez on 06/29/2008 15:55:52
That HU has crossovers and filters to dial in your amps better. To figure out how to set them correctly, break out the manual and read up on that feature section. (Page 16)
http://akamaipix.crutchfield.com/Manuals/113/113KDCX592.PDF
"Speaker settings that let you tailor the sound to the size and type of speakers in your car & System E's+ high- and low-pass filters."
The front amp HPF crossovers should be set to 220 Hz.
The rear HPF is set to 80 Hz.
The SW's LPF set to 80 Hz.
Nice HU here Zach. It's got some very nice features in all.
Quote: "ohh my amp only has a gain and frequency knob.... and a bass flat or treble switch, so i set frequency at 80hz, gain up just past half way and the switch on flat, which turned out to be a bass and mid combo."
The switch is your crossover setting feature. "Flat means the amp crossover is now full range. When set to "Flat", the crossover dial setting is disabled.
To enable the proper filter switch feature, use the "Bass" select if used as a sub amp @ 80 Hz
If powering the rear speakers only, use the "Treble" select position and the range @ 80 Hz.
You're getting there bud,
Swez
PS Hold off on the new ALT for now. If you note severe light dimming when listening to heavy bass material, then you may need that upgrade. For now, just enjoy the system, dial in the fine tuning features mentioned above and we'll see how this all shakes out OK?
Zach1989 on 06/29/2008 18:03:02
Ok that sounds good, i have a few other fabrications i have to do as well. I got a new suede shift boot and a devil shift knob, and with that shift knob i am planning on wiring it to my clutch pedal.
With that wired it will have a switch if you will, it will act as a connection for power so that every time i shift the eyes will glow red, (i have to make that myself but the knob was the devil itself).
So when I have all that situated hopefully by the end of the week i will be ready to start on the final project. Some bass in the back. I was thinking about the JBL GT5-12 as SQLThump mentioned earlier.
I was going to have a guy custom build my box because of the shape of my trunk, a dual 12 enclosure ported and tuned. Would that be a good match up? and if so what would be a good amp to power it?
swez on 06/30/2008 00:45:00
Nice subs and very efficient with power too. The G5-12 uses a 4 ohm SVC coil system and a pair of them wired parallel nets a solid 2 ohms. They are rated at 275 Wrms/sub.
Would you consider going sealed for this design? You can expect tight, full bass and these subs only need 1.0 cf/chamber. If that appeals to you, this amp would be a good match for power, price and reliabilty:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=235
If you really wanted to go ported, the space per chamber jumps to 1.75 cf/chamber and the amp will need a Subsonic/Infrasonic filter as well. Alpine has that feature in this amp:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=2461
Think it over as either of these amps draw about 50 A's at full power and you will need that larger ALT with either of these amps. They are both Class D sub amps and very solid performers. But feeding both amps will be a challenge to your electrical system when dialed up to high SPL levels.
Comments?
Swez
Zach1989 on 06/30/2008 02:22:22
I would do anything that matches up for a nice bass sound from the trunk, that has pretty good response time and a nice clear crisp sound. SQLThump said a ported enclosure would give it like double the bass response so i figured thats what I'd need to do.
But if the sealed box would sound just as loud with a great bass response I can do that as well. It doesnt matter how or what they are hooked into as long as they perform at their best LOL.
Which do you think would work better for my situation, it being a convertible and all? Ohhh i been meaning to ask you about the eq, should i hook both amps to the eq or have the eq hooked into the head unit along with the amps hooked into the head unit?
because right now i have the EQ hooked in by rear RCA and the the rear in on the eq go to my one amp and then they have a special sub rca setup on both the eq and HU, wasnt sure where to put rcas.
but as of right now they are all plugged into the eq and then the eq goes into the hu.
swez on 06/30/2008 07:09:15
Ported boxes are fine for heavy bass from Rap and Hip-Hop, but they tend to over-emphasize the low bass near the port tuning freq. It's a noticable bump of +6dB in that region, but accuracy of low bass falls off if the box is not done well.
Frankly, you will have plenty of bass SPL with what was mentioned earlier. (Sealed subs and either amp)
As for the EQ, refresh my memory on the model you have installed. It sounds like you have it installed right for the moment. The HU RCA's feed audio to the EQ, the EQ outputs go to your amp(s).
Swez
Zach1989 on 06/30/2008 14:54:05
This is the EQ I got:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3967
I think I will go with the GT5-12, two of them, with the JBL amplifier i Have already ran the 4 gauge wire tomorrow im ordering the ALT I had a few other projects to be finished with first.
I will have the guy custom make a sealed box for me because i love rap and hip hop but i do also listen to some classic rock and new age rock but no heavy metal screaming.
I think i got it hooked the way you mentioned above...
SQLThump on 06/30/2008 19:39:46
Great choice of amp and subs, and with your musical taste, this should pair up great.
A note on your enclosure, sealed boxes are really easy to design and build. For the price that most will charge for a custom enclosure, it is hardly worth it. If you have acess to a table saw, a drill with a variety of bits, a jisaw or sawsall, and possess enough comon sense not to lop a finger off, you can save yourself some massive dough.
Some places will charge $200 and upward for a custom built enclosure. One place wanted to charge a buddy $450 for a ported enclosure for the same GT5-12's you will be getting.
We can and happily will walk you through the steps if you have tool access and the cofidence to do so. It will make for good sound, fun and a learning expierence as well.
with your EQ, connect RCA inputs to your rear and sub channels to the matching inputs for your 6x9's and subs. Since your 3.5's are connected to the H/U, they will be unnaffected by EQ adjustments.
Your Eq will then control the RCA inputs into your amp, and signal cuts/boosts can then be made to your rear speakers ans subs. Keep in mind that EQ's are more for cutting out big peaks in the sound frequencies, and to provide slight boost to frequency ranges that need a little help to blend evenly with the whole band of sound.
When dialing in, I suggest doing the following:
Get a good CD with plenty of dynamic bass. Lil Jon's "Crunk Juice" is a favorite for me due to plenty of loud bass in many different tones and patterns
Set bass, midrange and treble on your Kenwood H/U to flat or zero. Go into the crossover menu, and select the highest possible setting for the front channels that your 3.5s will be playing on.
Turn your subwoofer control on both the H/U and Clarion EQ to the maximum level.
With all ampfier gains set to the lowest point, as well as bass boost and adjustable crossovers to their lowest point for subs, and highest point for upper range.
No turn up the stereo almost all the way up, or until it begins to distort. On a Kenwood H/u, this is usally volume setting 30 out of 35. If you make it all the way to 35 without audible distortion, I reccomend using volume setting 32 as your dial in and max volume.
Specifically pay attention at this point to sub distortion. If this occurs, turn down sub volume on the EQ first. Is distortion is still audible, turn the volume on the H.U down, then the sub volume if still noted. When the distortion stops, turn the EQ back up, if it is undistorted leave it there, if distortion reappears, leave it at a point of undistorted output.
Now lets do the amps. Turn your subs up first, to a level that sounnds slightly distorted, and then back off until it is clean sounding. Note fast bass repetitions, and if your subs are clearing them all with individual notes, or seems to be muddy accomplishing this. If its a bit slow hitting fast notes, turn the gain down a bit more
When dialing in bass boost, if neccessarry at all, very slowly turn the dial and keep an ear out for the sound listed above, if it is not providing a good boost of Db's without distorting the sound, DON"T USE IT. Unless a more aggressive bass entry is desired (as in bass levels when at lower volumes, and how the volumes are adjusted as you turn up the h/u), in this case, dial down your amp's gain, and compensate as best as possible with boost, as long as sound remains clean.
Now the crossover setting. Dial it up all the way at first, and then slowly turn it to a lower setting until the vocals and midbass are no longer playing through the subs. At this point, you should have some beautiful sounding bass coming into your car!
Time for the 2 channel now. It may be a good idea to turn down both your sub controls (EQ and H/U, not amplifier gain) so you can hear more easily. First, adjust it to a similar HP crossover setting that your lowpass on the amp left off at. Now turn up the gain again the same way as before, until distortion is evident, and then dialing slowly bact until it is gone.
Pay specific attention to the midbass performance. If you feel you want to get more output from the 6x9, but have distortion in this region, turn the crossover up to a higher point and try the gain again.
Sorry for throwing the book at you dude, but you have some great product selection here, and want to ake sure that it all is going to live up to JBL's loud and clean reputation. If you end up rolling around all distorted, I will have to round up the task force and kick in your door! GRIN
After this, match the crossover settings on the H/U close to the settings on your amp, going higher for subs and lower for rear speakers if really well matching point isn't available.
Also, as Swez mantioned earlier, hold off on the ALT for now. If you get everything installed, and more than slight headlight dimming is noted at high volume when all accessories are running, or are really worried about slight dimming getting you pulled over, then you need a better ALT. If none of the above are the case, you should probably be fine with what you have now.
Play it clean and have fun,
SQLThump HAPPY
Zach1989 on 07/1/2008 13:29:33
Dang SQL thanks a lot for your input what i might do is buy the deep cycle battery and call it cool for now, I am going to order the subs and maybe the JBL amp tonight as well.
That would be great if I cant save some money, but i would like to know how would i know if i have enough, too much or too little air in the box. As Swez said it would run good around 1cf/chamber.
Plus with my trunk it is kinda small and has a sharp inclination I have to make sure i can clear is so it would be a pretty heavy slanted box. I am glad i went with all JBL's they turned out to be one good setup and that kenwood really performs well.
Zach1989 on 07/1/2008 13:38:19
Hey quick question for the JBL amp could I get the JBL GTO601.1?
The only difference I think is maybe the year manufactured or the plexi glass see through? Because the one Swez mentioned was a JBL GTO 601.1II wasn't sure the difference as they both rate the same.
swez on 07/1/2008 14:55:59
I think you're looking at an older JBL model is all. (GTO600.1) The benefit to buying earlier models are often the price is lower. When most brands bring out a new line, the prices are often higher than older models w/ minmal changes to the guts.
Most change the casing and maybe add a few additional features, but the guts are only changed if there was a problem with reliability/field failures in an earlier design. (Upgrade the power supply, beef up the output section or add a few new features)
Why not?
Swez
Zach1989 on 07/2/2008 04:10:04
Ok thats what I will do then I will post again when i have all the equipment ready for install, but how will I know if i build my own box that i have too little too much or just the right amount of air space within the chambers?
SQLThump on 07/2/2008 10:36:42
Glad you enjoyed all the information....I think that was the longest post I ever made.
Before you order the JBL amps, keep this in mind......The older GTO series was rebuilt and "sequeled" (meaning revamped very quickly, reatining most of everything) due to a fe reliability problems. The sub amps werent affected, but the 2 and 4 channel amps were having problems going into protect mode when being used for subs. I was even a victim of this when my GTO 75.4II started going on the fritz after 2 hours on the frist one and 2 weeks on the second. 6 months and several pulled out hair follicles later, I am happy to see it gone.........
I was set up with an Alpine MRP M500 to push my GT5-12's with, and couldn't be happier. Even though it is rated 68 watts lower, it sounds much better, is more efficent, and carries the same fuse value. I would highly recommend them to anybody with GT5-12's in mind for their install.
I am not too sure on how to calculate airspace on a slanted backed enclosure, but a rectangular enclosure with two chambers of 13x13x10.75 will net you 1.05 cubic feet per chamber, and will have an external dimension of 14.5" height x 28.25" width x 12.25 depth. Let me know if those dimensions are ok for your car, and I will make you up a plan sheet you can print off, and will have step by step instructions on building it.
Also, have a few mor tricks for optimizing your 3.5's sound without using the EQ if you're interested.....
Also, consider a gel-cell or dry-cell as oppossed to a deep cycle battery. Deep cycles are OK but still based of fthe old lead-acid design. Gel-cells are much better packaged, and offer much better performance and longevity compared to any lead acid design. Not too mention the safety of a non-spillable design, you can mount of these upside down and it will be just fine, and they are not nearly as hazardous when ruptured in an accident. A little more expensive, yes, but definitely would be more than worth it.
swez on 07/2/2008 11:03:03
There are calculators out there to help the new box builder. In most cases we just plug in the external dimensions and let the calculator figure out the rest.
Even if we are off by +/- 5%, the subs will usually be OK. This site covers several basic designs. If your trunk is not very tall, consider the wedge 2 design. That is the most efficient design for larger subs and smaller profile boxes:
http://www.the12volt.com/caraudio/boxcalcs.asp#wed
The "H" , (1 & 2) may be fixed numbers in your case, but the "D" and "W" can be adjusted as needed. I would recommend a center divider panel between the subs. That way, if one sub fails, the remaining sub will have its own chamber to control the cone motion.
Finally, measure the trunk space and see what your dimensional limits are. Once that has been established, then the calculator will help determine the rest. Don't be concerned if you have to drop to a pair of 10's for this install. A pair of 10's can pump out great bass when the box is done properly.
The GT5-10 is now slouch either. It only needs 0.75 cf per chamber and the overall box design will be about 25% smaller too. (Sealed)
http://manuals.harman.com/JBL/CAR/Boxes%20and%20Parameters/GT510Tech_050108.pdf
can be adjusted to fit as needed.
I have rewired the 6.5" speakers and installed them ready for the amp in the trunk. and thursday (i decided to go with a new deck) a kenwood excelon is coming in.
Tomorrow i plan on putting the equalizer in and finish running amp wires, i got the RCAS to do and the remote turn ons as well as hiding the power wires. Now the question is, i got a 4 gauge wire for the amp to power the subs.
I was hoping to put in two 12" subwoofers into the trunk, (i knwo im very hard headed i liek things in pairs lol) I was thinking about some Alpine SWR-1242D - Alpine 12" Type R 1500W Dual 4 Ohm Subwoofer or maybe go ahead and go with the JBLs for a complete JBL setup.
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3148 or http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3166
but at the same time i was hoping for yuor input on the matter, and if you know of a better idea for the setup i have id like the input.
Also could you match me a good class d mono amp for the perfect setup? i appreciate any input you have and will respond to any questions, thanks again
Zach
Replies (29)
SQLThump on 06/24/2008 12:01:43
Perfect setup??? No such thing. It all depends on what subs you end up using in the end. The JBL P1222 is a beast, yes, but bit power hungry and will require a beast of an amp. Those GTO's are a bit dated now, and JBL is doing bigger and better things with their subs siince those GTO's.
Check out the JBL GT5-12's. They are more efficeint, require less power, and with a ported enclosure, make some mean bass with little amplification. A great amp to go with these would something making 400-600RMS at two ohms.
Also, did you say you are putting 6.5's in the trunk or did I read that wrong? I sure hope I read that wrong.........
Zach1989 on 06/24/2008 12:04:02
Yea i typed it in a little confusing the 6.5"s are in the car but i wired them into the trunk because the amp im using to power them is 50 watts rms X 2 and they have a rating of 60 rms each. i probably should clarified.
Also what about infinity's? But let me check out the Jbls first actually.............................
SQLThump on 06/24/2008 14:24:44
None of the Infinity lineups will really trounce anything JBL makes. Why you ask? Because they are made by the same parent company, Harmon International, otherwise known as Harmon Kardon. They make pretty great stuff all around, and have found little differences aside from looks when dealing with their products of comparable price/power range.
Glad to hear you have the 6.5s in the car. Good choice of amp power as well. I am sure they will hold up well. Also, the whole of the car audio world thanks you for losing the Dual H/U. Take it out for target practice, or have somebody run it over with an 18-wheeler. The Kenwood will serve you much better, and for longer than 3 months!GRIN
swez on 06/24/2008 14:58:08
If we look at the history of Harmon, they have 2 main audio/speaker systems in the mix. Infinity was designed for HT use and then adapted to mobile audio. JBL was primarily Pro/Commercial/Home Audio gear and has been adapted to mobile markets now too. The net affect, they are both hybrids for mobile audio and lots of speaker design experience on both sides of the table. To be sure, they share technology ideas and compete for market share as well. That's a good strategy for Harmon and the consumer.
In your case, it seems like JBL is the main contender. The P1222D woofers are "very efficient", can take plenty of power and don't require huge boxes to make them sound great. They are rated at 400 RMS per each, but that does not mean they won't perform well with a smaller amp too. Here, the ideal amp will be 2 ohm stable and deliver 500-800 Wrms @ 2 ohms. The trick is to use a bass amp that is Class D, and does not stress the electrical system of this car beyond limits that demand expensive electrical upgrades. (H.O. ALT and extra BAT's)
Think about that a while before you proceed,
Swez
Zach1989 on 06/25/2008 02:18:55
I just put in a brand new ALT. and i was thinking about getting one of the yellow top deep cycle batteries for a little added protection, as for the JBL's thats pretty much what i was thinking about sticking to. A lot of people said good things and they seem to be pretty good speakers.
Based on my sitution would it be better for me to get the P1222D's or the GT5-12? I believe that my ALT. is pretty strong but it also has a lot of power already being used by other parts of the vehicle.
Correct me if im wrong but, in order to get an "amp rating" you take the rms power you will be using and divide it by the output voltage to get the amount of amps i should be using?
In this case i have an 80 amp ALT and if i am correct again about 60 Amps are already being used, so i wasnt sure if taking two gt5-12's and putting them in a ported box would be a more efficient way to get bass without a huge tax on my system, or would it work out just fine with two P1222D's?
swez on 06/25/2008 04:39:31
Let's fill in a few blanks before you choose anything more than what's on the table.
A stock 80A ALT will only produce max output above ~2300 RPM. At idle speeds, the output is about half of that. One can reduce the pully diameter on the ALT to increase the idle speed rotation and get more output from the ALT. (Easy and low cost option)
Depending on all the electronics in this vehicle, it will operate fine at 30-40A's, just cruising along. The big drains come only when operating headlamps, fog/driving beams, blower motor, power seats/windows and rear window defogger circuits.
Now, when amplifiers are added, the power demand will change dramatically depending on volume level settings and how hard we push the bass engine. The most demanding scenario comes from pure test tones and sustained low bass notes at high SPL levels.
When listening to music, the RMS power levels change constantly with the music content. Rap and Hip Hop cuts have very high bass content and this is where amps, subs and electrical systems are put to the "daily driver" test. It's most noticable at night when we crank up the bass, have the headlights on and maybe running the Air Conditioner too.
At a stop light, the engine RPM is low and so is ALT output. Dial up the bass and the headlights will dim to some degree. (Big bass thumps)That's normal and to be expected. To prevent/limit that, we simply dial back on the HU volume or if the sub amp has a remote bass control, dial back and all is well. (Common sense right?)
OK, these are the basics of what you can expect. Adding a Optima Yellow Top can help. Especially if it has a high CCA rating. (Cold Cranking Amp rating of 750 or higher) This is considered a "buffer" in the power supply to the vehicle. When the ALT cannot produce enough current, the BAT makes up the difference for a short time. However, the BAT is now depleted to a degree and the ALT needs to recharge it to normal levels. That's the cycle of events we have to manage. (Got the picture?)
Confirm your understanding of this scenario and then we can move on to the next phase... sub/amp choices.
Swez
Zach1989 on 06/25/2008 05:33:42
Ok i Understand that, the yellow top i heard can take big drops, charges real quick, and also can run to just about nothing and still be stronger than a regular battery becaus eit is a deep cycle one, howver i did some research.
A very similair car to mine has the same mounting and whatnot i just need to change the pulleys this ALT has a rating of 115, which this would only cost me 100" to buy with no core charge i think that and the deep cycle would be a good combo, or no?
That should keep everything at a nice limit and still have at least 40 or 50 Amps to play with and the power coming to the 6.5"s out of the little amp is only like 8 amps (RMS/ 12), (has a 25 amp fuse) which 115 amps -- 70 amps = 45 amps which at that rate should give me about 500 or 600 watts rms at 12 volts battery charge to play with.
Is that correct in the mathematic or am i just totally in the wrong step? If I am correct then go ahead and well see the sub/amp choices that will work. Thanks Swez for the very quick and detailed assistance.
Ps. by the way i ran the rcas and almost have the remote turn ons to the head unit space and i will have them finished with wiring tomorrow and maybe the head unit and EQ if i have time.
swez on 06/25/2008 08:42:50
The Yellow Top is a "Deep Cycle" battery. It can take more than 300 complete discharges and still work fine. (Try that on a normal car battery and it's toast after only a handful of deep discharges) Good choice.
The 115A ALT is a good deal if new, out of the box and has a decent warranty. That's a very fair price. ($100.00)
Another thing to remember, amplifiers consume more power than they can put out the back end. Class D bass amps are about 80% eff. Class A/B full range amps are about 60% eff. We need to consider that when choosing the rated power of a given set of amplifiers.
When calculating power, we use Ohm's Law. Voltage sq/Resistance = Power in watts. We measure the AC voltage coming out of the amp to the speaker and run the equation to determine RMS watts the speaker is actually getting. Here's the deal:
Speaker is 2 ohms nominal
Voltage reading is 32 volts AC
Power in RMS watts: 32 x 32 = 1024/2 = 512 watts to sub(s)
Not a bad number huh? If this is a Class D amp, we can calculate the total power draw comsumed as well: 512/.8 = 640 watts consumed. We can also figure out how much actual current this amp draws since we know input voltage and wattage consumed. This would be a worst case scenario using long duration test tones. Normal music is not so severe.
Source voltage: 14.0 VDC (+/- 0.2 volts)
Watts consumed: 640
Amperage draw: 640/14 = 45.7A's
This is just scratching the surface Zach. The math is more complex than I am feeding you here. But it's close enough to get a feel for how amps/speakers work in car audio systems. Don't see a need to go much deeper for now. It'll just make your head spin.
When installing the EQ, it would be wise to tap the EQ REMote trigger and main power lines to the acc/ign line on your HU. The HU REM line is used to feed the amps only. Make sure to fuse the EQ main power line too. This will prevent over-loading the HU REMote power supply.
Good luck on your install steps. Just take your time, do it well and everything should come out noise free later. Just make sure your HU and EQ grounds are connected to bare metal grounds in the dash, floor panel or firewall. DO NOT USE THE FACTORY HARNESS GROUND! This should prevent or minimize ground loop noise later.
Swez
PS Am on vacation for now and have more time to help guys on CK. It feels good to be back on the board again and it's great to help others.
Zach1989 on 06/25/2008 15:37:52
Wow thats crazy, way more complex than i ever thought lol. So my plan of action will be then getting the yellow top and the ALT. So if i crank the amp up to 115 and im only using roughly 60, then what could be some good subs and amp combo we can use?
Might as well stick with JBL's since thats all i got in the car now and you mentioned before of their experience, any amp subs combos come to mind, like i said before im looking for two 12"s and an amp to match.
Ohhh and as for the wiring of the EQ and HU, my plan was right on with yours i have an inline fuse (20AMP ok?) and i was going to run the rem. turn on and the power to the HUs power supply and then run its own ground and the same goes to the HU, pretty much liek you said before.
I know a little bit about screwing up due to my last projects i was in a rush and wanted it to be done no matter the cost. Those times the cost was faulty equipment with horrible sound. I would be in there like everyday trying to fix the problem and whatever.
So now i decided im not gonna waste my money anymore, do it all the right way the first time, and get good quality subs amps speakers HU's EQS so that when the time comes it will perform and maintain performance.
Anyways, thanks again for the audio lesson im going to write that down and keep it, you never know when i can help someone or heck i might need it again as well.
swez on 06/26/2008 22:10:19
When fusing your HU/EQ, look at fuse rating on the HU and add a few more amperes for the EQ. If you do use a 20A fuse, use #12 gage line as the main feeder off it's own circuit so you don't blow any fuses in the fuse panel.
For this much current, it might be a good idea to use a relay too. Are you familiar with the workings of relays and how to install them properly? Have a look here for details:
http://www.bcae1.com/relays.htm
Swez
Zach1989 on 06/28/2008 13:33:12
Ok Ill do that, but ive never worked with relays or any relay type systems, im planning on installing everything tomorrow. well the wiring of it all together at least. then i have to see about mounting. But thats no problem little bit of modification itll look like it grew there.
But Ill look into those relays and let you know on progress hopefully if everything goes smoothly i should have the small amp hooked up along with the hu/eq and should hear what those jbls sound like.
Then im on to my last task and the most important one of all, lol, find a good amp / sub combo hopefully by the end of next weekend i can have everything all good and hear the finished product. itll be real nice.
swez on 06/28/2008 15:41:39
Just make sure you get the common Bosche type, 5 pin relay. (SPDT) They cost about $4 at any good autoparts store and rated between 20-40A's.
It's good to get the harness with pigtails so you can wire everything up with crimp connectors and hide it in the dash. Just follow the diagrams on the link above and it should come out good. If you need help, don't guess. Here's another site that covers relays in simple terms:
http://www.the12volt.com/relays/relays.asp
Swez
PS For this install, a diode shunt is not required.
Zach1989 on 06/29/2008 09:04:37
Alright thanks a bunch Swez. I have the HU wired and the EQ as well I figured it all out, on thing left to do is find a ground and mount it all. Then tune the amp and test everything out.
I am actually very excited to see how it sounds, I have done everything the right way the first time so there would be no mistakes, I have the 115 amp alternator on order and i will buy the yellow top battery after the ALT. is installed.
That means we have like i said about 40 -50 extra amps to play with for the amp and subs. So i guess that our next step.
swez on 06/29/2008 09:26:41
Did you install the relay as mentioned too or no?
Good progress so far and you can do a preliminary amp setting if you wish.
For now, use these settings as a guide:
Sub amp: Low Pass Filter set at ~80 Hz
Fullrange amp: High Pass Filter set at ~80 Hz
Gain setting on all amps: Set to middle point of adjustment range
Since the front stage is low power off the HU, you'll want to try and balance the rear speaker amp to compliment the front stage, but not over-power the fronts. Once you reach a nice balance point with amp gain settings, then it's time to bring up the sub to a level you prefer.
FYI: If this HU has crossover menu settings for the front channels, start at ~300-400 Hz w/ the HPF settings. This will keep unwanted bass from the 3.5" GTO's. If the HU has no menu settings, passive filters are needed, (Bass blockers) to do this for you.
Got all that?
Swez
Zach1989 on 06/29/2008 13:04:45
Here is the HU:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=6343
Wasn't sure what you meant about crossover menu settings so i thought maybe you might be able to tell, lol. Hooked everything up as planned but now the eq wont turn on.
It was working just fine then once i hooked the amp up it stopped working, i think i might have shorted something out. The HU works but the amp and EQ dont turn on, i wonder if maybe the remote turn on is what the problem.
Ill keep you posted though.
Zach1989 on 06/29/2008 14:48:30
Ok found the problem.... what was going on was the power ant. that i had the rem. turn ons hooked up to.....well when the radio is on so is the power ant. but when the cd is in the power ant. isnt on anymore.
So that being the case there is another connection on the HU, the PO. continuous so that is like a power ANT that stays on so i hooked it to that and were good. let me tell you it sounds GREAT for what it is. I think it was my best sounding install.
I thank you guys a lot for your help up to this point and we finally made it to the last step. I will definitely be donation again when i get my pay on thursday. This site has to stay up and running for everyone to share ideas and help. thanks again...
ohh my amp only has a gain and frequency knob.... and a bass flat or treble switch, so i set frequency at 80hz, gain up just past half way and the switch on flat, which turned out to be a bass and mid combo i think....
swez on 06/29/2008 15:55:52
That HU has crossovers and filters to dial in your amps better. To figure out how to set them correctly, break out the manual and read up on that feature section. (Page 16)
http://akamaipix.crutchfield.com/Manuals/113/113KDCX592.PDF
"Speaker settings that let you tailor the sound to the size and type of speakers in your car & System E's+ high- and low-pass filters."
The front amp HPF crossovers should be set to 220 Hz.
The rear HPF is set to 80 Hz.
The SW's LPF set to 80 Hz.
Nice HU here Zach. It's got some very nice features in all.
Quote: "ohh my amp only has a gain and frequency knob.... and a bass flat or treble switch, so i set frequency at 80hz, gain up just past half way and the switch on flat, which turned out to be a bass and mid combo."
The switch is your crossover setting feature. "Flat means the amp crossover is now full range. When set to "Flat", the crossover dial setting is disabled.
To enable the proper filter switch feature, use the "Bass" select if used as a sub amp @ 80 Hz
If powering the rear speakers only, use the "Treble" select position and the range @ 80 Hz.
You're getting there bud,
Swez
PS Hold off on the new ALT for now. If you note severe light dimming when listening to heavy bass material, then you may need that upgrade. For now, just enjoy the system, dial in the fine tuning features mentioned above and we'll see how this all shakes out OK?
Zach1989 on 06/29/2008 18:03:02
Ok that sounds good, i have a few other fabrications i have to do as well. I got a new suede shift boot and a devil shift knob, and with that shift knob i am planning on wiring it to my clutch pedal.
With that wired it will have a switch if you will, it will act as a connection for power so that every time i shift the eyes will glow red, (i have to make that myself but the knob was the devil itself).
So when I have all that situated hopefully by the end of the week i will be ready to start on the final project. Some bass in the back. I was thinking about the JBL GT5-12 as SQLThump mentioned earlier.
I was going to have a guy custom build my box because of the shape of my trunk, a dual 12 enclosure ported and tuned. Would that be a good match up? and if so what would be a good amp to power it?
swez on 06/30/2008 00:45:00
Nice subs and very efficient with power too. The G5-12 uses a 4 ohm SVC coil system and a pair of them wired parallel nets a solid 2 ohms. They are rated at 275 Wrms/sub.
Would you consider going sealed for this design? You can expect tight, full bass and these subs only need 1.0 cf/chamber. If that appeals to you, this amp would be a good match for power, price and reliabilty:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=235
If you really wanted to go ported, the space per chamber jumps to 1.75 cf/chamber and the amp will need a Subsonic/Infrasonic filter as well. Alpine has that feature in this amp:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=2461
Think it over as either of these amps draw about 50 A's at full power and you will need that larger ALT with either of these amps. They are both Class D sub amps and very solid performers. But feeding both amps will be a challenge to your electrical system when dialed up to high SPL levels.
Comments?
Swez
Zach1989 on 06/30/2008 02:22:22
I would do anything that matches up for a nice bass sound from the trunk, that has pretty good response time and a nice clear crisp sound. SQLThump said a ported enclosure would give it like double the bass response so i figured thats what I'd need to do.
But if the sealed box would sound just as loud with a great bass response I can do that as well. It doesnt matter how or what they are hooked into as long as they perform at their best LOL.
Which do you think would work better for my situation, it being a convertible and all? Ohhh i been meaning to ask you about the eq, should i hook both amps to the eq or have the eq hooked into the head unit along with the amps hooked into the head unit?
because right now i have the EQ hooked in by rear RCA and the the rear in on the eq go to my one amp and then they have a special sub rca setup on both the eq and HU, wasnt sure where to put rcas.
but as of right now they are all plugged into the eq and then the eq goes into the hu.
swez on 06/30/2008 07:09:15
Ported boxes are fine for heavy bass from Rap and Hip-Hop, but they tend to over-emphasize the low bass near the port tuning freq. It's a noticable bump of +6dB in that region, but accuracy of low bass falls off if the box is not done well.
Frankly, you will have plenty of bass SPL with what was mentioned earlier. (Sealed subs and either amp)
As for the EQ, refresh my memory on the model you have installed. It sounds like you have it installed right for the moment. The HU RCA's feed audio to the EQ, the EQ outputs go to your amp(s).
Swez
Zach1989 on 06/30/2008 14:54:05
This is the EQ I got:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3967
I think I will go with the GT5-12, two of them, with the JBL amplifier i Have already ran the 4 gauge wire tomorrow im ordering the ALT I had a few other projects to be finished with first.
I will have the guy custom make a sealed box for me because i love rap and hip hop but i do also listen to some classic rock and new age rock but no heavy metal screaming.
I think i got it hooked the way you mentioned above...
SQLThump on 06/30/2008 19:39:46
Great choice of amp and subs, and with your musical taste, this should pair up great.
A note on your enclosure, sealed boxes are really easy to design and build. For the price that most will charge for a custom enclosure, it is hardly worth it. If you have acess to a table saw, a drill with a variety of bits, a jisaw or sawsall, and possess enough comon sense not to lop a finger off, you can save yourself some massive dough.
Some places will charge $200 and upward for a custom built enclosure. One place wanted to charge a buddy $450 for a ported enclosure for the same GT5-12's you will be getting.
We can and happily will walk you through the steps if you have tool access and the cofidence to do so. It will make for good sound, fun and a learning expierence as well.
with your EQ, connect RCA inputs to your rear and sub channels to the matching inputs for your 6x9's and subs. Since your 3.5's are connected to the H/U, they will be unnaffected by EQ adjustments.
Your Eq will then control the RCA inputs into your amp, and signal cuts/boosts can then be made to your rear speakers ans subs. Keep in mind that EQ's are more for cutting out big peaks in the sound frequencies, and to provide slight boost to frequency ranges that need a little help to blend evenly with the whole band of sound.
When dialing in, I suggest doing the following:
Get a good CD with plenty of dynamic bass. Lil Jon's "Crunk Juice" is a favorite for me due to plenty of loud bass in many different tones and patterns
Set bass, midrange and treble on your Kenwood H/U to flat or zero. Go into the crossover menu, and select the highest possible setting for the front channels that your 3.5s will be playing on.
Turn your subwoofer control on both the H/U and Clarion EQ to the maximum level.
With all ampfier gains set to the lowest point, as well as bass boost and adjustable crossovers to their lowest point for subs, and highest point for upper range.
No turn up the stereo almost all the way up, or until it begins to distort. On a Kenwood H/u, this is usally volume setting 30 out of 35. If you make it all the way to 35 without audible distortion, I reccomend using volume setting 32 as your dial in and max volume.
Specifically pay attention at this point to sub distortion. If this occurs, turn down sub volume on the EQ first. Is distortion is still audible, turn the volume on the H.U down, then the sub volume if still noted. When the distortion stops, turn the EQ back up, if it is undistorted leave it there, if distortion reappears, leave it at a point of undistorted output.
Now lets do the amps. Turn your subs up first, to a level that sounnds slightly distorted, and then back off until it is clean sounding. Note fast bass repetitions, and if your subs are clearing them all with individual notes, or seems to be muddy accomplishing this. If its a bit slow hitting fast notes, turn the gain down a bit more
When dialing in bass boost, if neccessarry at all, very slowly turn the dial and keep an ear out for the sound listed above, if it is not providing a good boost of Db's without distorting the sound, DON"T USE IT. Unless a more aggressive bass entry is desired (as in bass levels when at lower volumes, and how the volumes are adjusted as you turn up the h/u), in this case, dial down your amp's gain, and compensate as best as possible with boost, as long as sound remains clean.
Now the crossover setting. Dial it up all the way at first, and then slowly turn it to a lower setting until the vocals and midbass are no longer playing through the subs. At this point, you should have some beautiful sounding bass coming into your car!
Time for the 2 channel now. It may be a good idea to turn down both your sub controls (EQ and H/U, not amplifier gain) so you can hear more easily. First, adjust it to a similar HP crossover setting that your lowpass on the amp left off at. Now turn up the gain again the same way as before, until distortion is evident, and then dialing slowly bact until it is gone.
Pay specific attention to the midbass performance. If you feel you want to get more output from the 6x9, but have distortion in this region, turn the crossover up to a higher point and try the gain again.
Sorry for throwing the book at you dude, but you have some great product selection here, and want to ake sure that it all is going to live up to JBL's loud and clean reputation. If you end up rolling around all distorted, I will have to round up the task force and kick in your door! GRIN
After this, match the crossover settings on the H/U close to the settings on your amp, going higher for subs and lower for rear speakers if really well matching point isn't available.
Also, as Swez mantioned earlier, hold off on the ALT for now. If you get everything installed, and more than slight headlight dimming is noted at high volume when all accessories are running, or are really worried about slight dimming getting you pulled over, then you need a better ALT. If none of the above are the case, you should probably be fine with what you have now.
Play it clean and have fun,
SQLThump HAPPY
Zach1989 on 07/1/2008 13:29:33
Dang SQL thanks a lot for your input what i might do is buy the deep cycle battery and call it cool for now, I am going to order the subs and maybe the JBL amp tonight as well.
That would be great if I cant save some money, but i would like to know how would i know if i have enough, too much or too little air in the box. As Swez said it would run good around 1cf/chamber.
Plus with my trunk it is kinda small and has a sharp inclination I have to make sure i can clear is so it would be a pretty heavy slanted box. I am glad i went with all JBL's they turned out to be one good setup and that kenwood really performs well.
Zach1989 on 07/1/2008 13:38:19
Hey quick question for the JBL amp could I get the JBL GTO601.1?
The only difference I think is maybe the year manufactured or the plexi glass see through? Because the one Swez mentioned was a JBL GTO 601.1II wasn't sure the difference as they both rate the same.
swez on 07/1/2008 14:55:59
I think you're looking at an older JBL model is all. (GTO600.1) The benefit to buying earlier models are often the price is lower. When most brands bring out a new line, the prices are often higher than older models w/ minmal changes to the guts.
Most change the casing and maybe add a few additional features, but the guts are only changed if there was a problem with reliability/field failures in an earlier design. (Upgrade the power supply, beef up the output section or add a few new features)
Why not?
Swez
Zach1989 on 07/2/2008 04:10:04
Ok thats what I will do then I will post again when i have all the equipment ready for install, but how will I know if i build my own box that i have too little too much or just the right amount of air space within the chambers?
SQLThump on 07/2/2008 10:36:42
Glad you enjoyed all the information....I think that was the longest post I ever made.
Before you order the JBL amps, keep this in mind......The older GTO series was rebuilt and "sequeled" (meaning revamped very quickly, reatining most of everything) due to a fe reliability problems. The sub amps werent affected, but the 2 and 4 channel amps were having problems going into protect mode when being used for subs. I was even a victim of this when my GTO 75.4II started going on the fritz after 2 hours on the frist one and 2 weeks on the second. 6 months and several pulled out hair follicles later, I am happy to see it gone.........
I was set up with an Alpine MRP M500 to push my GT5-12's with, and couldn't be happier. Even though it is rated 68 watts lower, it sounds much better, is more efficent, and carries the same fuse value. I would highly recommend them to anybody with GT5-12's in mind for their install.
I am not too sure on how to calculate airspace on a slanted backed enclosure, but a rectangular enclosure with two chambers of 13x13x10.75 will net you 1.05 cubic feet per chamber, and will have an external dimension of 14.5" height x 28.25" width x 12.25 depth. Let me know if those dimensions are ok for your car, and I will make you up a plan sheet you can print off, and will have step by step instructions on building it.
Also, have a few mor tricks for optimizing your 3.5's sound without using the EQ if you're interested.....
Also, consider a gel-cell or dry-cell as oppossed to a deep cycle battery. Deep cycles are OK but still based of fthe old lead-acid design. Gel-cells are much better packaged, and offer much better performance and longevity compared to any lead acid design. Not too mention the safety of a non-spillable design, you can mount of these upside down and it will be just fine, and they are not nearly as hazardous when ruptured in an accident. A little more expensive, yes, but definitely would be more than worth it.
swez on 07/2/2008 11:03:03
There are calculators out there to help the new box builder. In most cases we just plug in the external dimensions and let the calculator figure out the rest.
Even if we are off by +/- 5%, the subs will usually be OK. This site covers several basic designs. If your trunk is not very tall, consider the wedge 2 design. That is the most efficient design for larger subs and smaller profile boxes:
http://www.the12volt.com/caraudio/boxcalcs.asp#wed
The "H" , (1 & 2) may be fixed numbers in your case, but the "D" and "W" can be adjusted as needed. I would recommend a center divider panel between the subs. That way, if one sub fails, the remaining sub will have its own chamber to control the cone motion.
Finally, measure the trunk space and see what your dimensional limits are. Once that has been established, then the calculator will help determine the rest. Don't be concerned if you have to drop to a pair of 10's for this install. A pair of 10's can pump out great bass when the box is done properly.
The GT5-10 is now slouch either. It only needs 0.75 cf per chamber and the overall box design will be about 25% smaller too. (Sealed)
http://manuals.harman.com/JBL/CAR/Boxes%20and%20Parameters/GT510Tech_050108.pdf
can be adjusted to fit as needed.
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