Hello. This is my first post here. Hopefully someone can help me out. I have a PPI Art Series 200.2 amp (2-channel, rated at 200 watts). I previously had this amp hooked up to 2 Cerwin Vega DVC subs, and it pushed them VERY well. I want to bridge it down and hook it up to a single Infinity Kappa Perfect 12.1d sub (DVC, wired in parallel). The sub says that the recommended power range is 75-350 watts RMS (175 watts per coil). I have heard of people having problems with this sub when it is underpowered. Will this be a problem for me??? What could happen to the sub if it is underpowered? Should I get a bigger amp just to be safe? Any comments/suggestions are greatly appreciated. Thanks!
Replies (20)
Swez on 10/20/2003 17:35:48
Should be fine if you bridge the amp. In fact, you'll have closer to 400 watts RMS from this amp when bridged... BUT YOU MUST USE A 4 OHM SPEAKER LOAD WHEN BRIDGED.
The Perfect DVC is 2/4/8 ohms, depending on your wiring per each. If you use 2, the DVC is fine. If you only use 1 sub, get the 4 ohm SVC model.
NOTE: If you go lower than 4 ohms to the amp when bridged, it will damage the amp.
http://www.justwoofers.com/Woofer_Pages/Infinity/infinity
_KappaPerfect.htm KAPPA PERFECT12 SALE! $154.99 4 OHMS, SVC
http://www.justwoofers.com/Woofer_Pages/Infinity/infinity
_KappaPerfectDVC.htm 2-INF-KAPPA12.1D TWO INFINITY KAPPA 12.1D SUBWOOFERS SALE! $159.99/ea, $319.99/pr.
Underpowering this sub(s)... nope! Speakers are made to operate in a range of input power. They are rated for max watts (RMS/PEAK) but will operate fine and last longer if you don't run the amp into clipping mode. (high distortion)
Does your present speakers play well at low volume levels? Sure! They sound better when there is adequate power to get them cranking, but low distortion... but still sound fine at 30% of max right? Same for subs.
Swez COFFEE
PS Welcome to the forum... come stay a while and learn. SMILE
Tray on 10/21/2003 13:44:35
What will happen if you underpower the sub, is that the output will be slightly lower.
The problems you have heard are most likely due to abuse of the sub, and clipping issues with the amp. I have run my Perfect 10.1s on as little as 75 watts, and as much as 700 watts.
I wouldn't recommend going any higher than Infinity recommends, unless you have an extremely well built setup, and even then, I would keep it safe.
The main thing you have to remember, is you can't just turn up the gains, and bass boost, and expect your sub to perform that much better. If you have reasonable expectations, and don't try to exceed the limits of your equipment, that combo should be just fine. If it turns out you want/need more output, then an amplifier upgrade would be in order.
I can say that if you build the right box, the Perfects sound amazing.
Swez on 10/21/2003 14:33:40
Well said Tray!
Swez
VRWRX on 10/21/2003 18:09:11
Thanks for the input guys! I am a relative noob to car stereos. I have had systems in my cars, but I have never took the time to actually figure out how to do it right. I just hooked it up and turned up the volume. So please excuse my naiveness with these questions. Is clipping the amps way of saying that it's overworked? How do I keep the amp from clipping? Would I be able to hear the clipping? I have heard other amps go into a sort of "protect" mode, but I don't know that I have actually heard clipping. I know that I have had the gain on this amp turned up all the way with no problems (at least not audible) with my previous speakers (and they were not damaged). I have been trying to do some research on it, and from what I can gather, basically the only thing I can do to prevent clipping is to not have the gain up all the way. But I could be completely wrong. Is that correct? Also, why shouldn't I put a 2 ohm load to the amp? Will that just cause it to run too hot? I know that amp is stable at 2 ohms. Will 4 ohms be safer? Wouldn't it be louder at 2 ohms? Again, thanks for your help and feel free to shoot any of this down if it's incorrect. I'm just trying to learn...
Swez on 10/21/2003 22:50:26
Most 2 channel amps are 2 ohms stable in stereo and deliver more power to the sub(s) on that channel. However, when bridging a 2 channel amp to MONO, you get the most safe power to a 4 ohm load. If you run the amp at 2 ohms in MONO, it will overheat, run the transistors much harder and shorten the life of the amp considerably.
There are High Current (HC) amps that use 2 channels and can be run as low as 1 ohm in MONO, but thes amps are real current hogs and used mostly in high SPL applications. Very expensive too.
Clipping: This is when the input signal waveform is greatly distorted and out of specifications to the amps normal operating parameters. Clipping can be be heard in mid/highs by harsh, shrill and unatural sounding vocals, guitar and cymbals.
Clipping in woofer amps are bit harder to detect. Ususally the bass gets mushy, poor definition and just not crisp.
Here, read this for more details: http://www.eatel.net/~amptech/elecdisc/2ltlpwr.htm
Swez
VRWRX on 10/22/2003 10:02:02
Cool, thanks. Now I understand why I need to run the SVC 4 ohm sub. That makes sense. But after all that, I still don't know how to prevent my amp from clipping. Is there even anything you can do to prevent it?
Swez on 10/22/2003 10:48:16
Proper gain settings on the amp that match the HU output level will prevent the amp form "excessive" clipping. Some amps have a clipping LED indicator. Many do not and you have to either use an O-Scope to detect clipping or your ears/eyes will also tell you when excessive clipping is happening.
Best method w/o an O-Scope:
1. Know where your HU volume setting are starting to distort. (the HU is clipping) Usually, 50-70% of the HU volume max setting is where the HU begins to clip. (the more bass boost on HU is used, the sooner the clipping will begin)
2. Know what the HU RCA output voltage is (2.0 - 6.0 volts is common)
3. Match the amp input gains with your HU output levels. (Ie: if the HU puts out 2.0 volts, set amp gain(s) at 2.0 volts as well)
TIP:
I have found the best way to determine if system is clipping, is to open the doors and crack the truck/hatch a few inches. Then, turn off the sub amp or pull the RCA's for now.
Turn on your system and get out of the car and stand in back of vehicle a few feet and listen carefully. If the full range speakers are full and clean, you're in the safe zone. If you hear shrill, harsh or unatural mids/high... the system is clipping already. Dial back on the HU volume until it is clear and clean.
Now, reconnect the sub amp and listen again. Should hear clear, full & tight bass coming from the subs. If mushy, poorly defined bass is noted, amp gain adjustments may clear it up.
Basically, going from one extreme (high clipping levels) to (low clipping levels) takes patience and a good ear. Getting out of the vehicle and standing away from the car a few feet are the best way to determine if your system is clipping (excess distortions) or running at optimal settings.
Does that help?
Swez
VRWRX on 10/22/2003 13:50:19
Yes, that does help. I guess I'll just have to install it and see what happens. I will be modest with the gain and try to listen carefully for any distortion. I will try the tip you gave to try to see if I can detect anything. Thanks a ton for all your patience and help!
Swez on 10/22/2003 14:24:47
When you run your setup testing, use music material you are very familiar with. This way, you can detect suble/major changes in sound quality.
I think there is an FAQ on this site that talks about "Tweaking your Subs for success." The same principle applies to mids and highs. Basically, use the HU tone controls sparingly to boost bass or highs.(+3dB) is usually enough.
Same thing on sub amp & bass boost... best not to use it at all unless there's a real weakness in bass @ 45 Hz range. Again, a little boost is all that should be used or it may damage your subs.
You'll be fine as we coach you through the details,
Swez
VRWRX on 10/27/2003 17:25:32
OK, so I have one more question. I will be using a Line-Out Converter because I wish to keep my stock HU for the in-dash changer and as a theft deterrent. Will the LOC affect any of this? I have heard good things about the David Navone LOC's,
http://www.davidnavone.com/adaptor_products.htm
but I don't know which one to get (the N-777 or N-7V). What benefit does the variable volt output on the N-7V give me? Is that something I should be concerned with? Are there other LOC's that may suit my needs better?
As a caviot to that, I have the premium sound in my car ('02 Subaru Impreza WRX) with a powered sub under the passenger seat. How will I deal with unhooking that and using the LOC? I'm not sure what kind of wires are run from the deck to the sub under the seat. I know they aren't RCA's, so I would assume they are just speaker wires. So would I just hook up the LOC to the speaker wires running to the sub under the seat? I am a little confused on exactly the LOC's work, so any input would be great. Thanks again!!!
Swez on 10/27/2003 19:47:02
Very good product line you have found. Navone and Clark are two of the top Car Audio engineers in the game.
I have a few questions for you before choosing the right LOC:
1. The stock HU has a powered sub as part of the package now... how many watts does this sub amp feed the present sub?
2. Does you PPI amp have RCA, balanced line or both for inputs?
3. What is the gain range on your PPI amp settings? (250Mv - ? volts)
4. Assume you only want sub signals from the LOC to amp yes?
There are several versions of convertors that you may use for this application. Not sure how many watts you have powering that OEM sub system, so having the ability to attenuate (lower the signal voltage ) to meet amp input needs will help a lot. The N-7V makes sense here and is adjustable. It is full range, and your amp LP filter can do what is needed to get the proper bass range to your sub.
The 2 products mentioned are both full range. You have LP LOC device versions too and one that is adjustable. The only thing I did not like here, is the +12dB bass boost feature @ 40 Hz. Your amp has that already and that much boost can be tough on a sub. The 20 Hz infrasonic filter is appropriate with ported sub designs, but not really needed in a sealed allpication.
The N-85V seem like the best overall choice as it can take amplified signals from factory amps and drop them usable amp input levels. This too, has the +12 dB bass boost feature and SS filter. I would like to see this package modified to have a +3 ~ +6dB variable bass boost... not a fixed+12 dB boost.
You may want to call them and explain your applications and ask them for a best fit LOC. I would!
Swez
Reply to the questions noted and will advise your bets choices OK?
Swez
VRWRX on 10/28/2003 10:17:51
1. I'm not exactly sure how many watts the present sub is getting. I am trying to get the answer. Hopefully I will have it soon.
2. My PPI amp has only RCA inputs.
3. I'm not sure on the gain range of the amp right now. It's currently in storage, so I can't really look at it. If necessary, I can go look, though.
4. Yes, I only want the sub signals from the LOC to the amp.
2 things -
1. My amp is pretty old, and does not have any sort of crossover function. When I had it hooked up previously, I was just using an F-Mod hooked to the RCA's to filter out what I didn't want the subs to see. Just FYI - I don't know if it matters.
2. Couldn't I just tap into the rear speaker leads for the LOC? Then I could just unhook the stock sub, take it out, and not have to worry about those connections. Then I wouldn't have messed with any of that, so if I ever needed to return it back to stock, nothing would have been changed.
VRWRX on 10/28/2003 13:13:45
Update:
I think the sub amp feeds the stock sub 30 watts.
Swez on 10/28/2003 14:03:22
OK, that seems in order and if you have FMods for your inputs to the PPI amp, that is sufficient if in the 80-100 Hz range. (LPF)
If you know the amp model, you may be able to locate the data on same at the PPI site. If it is that old, they may have an archive search so you can locate what you need on the gains. Probably 250Mv - 4.0 volts, may only 2.0 volts... but the adjustable LOC can compensate for that too.
As I think it over a bit more, the N-7V may be your best choice as it has variable output source, full range and you should be able to connect right off the rear full range speakers from the HU amps. You can leave the sub as is, just pull the wires off so when you sell the vehicle, can reconnect all that with minimal effort?
The other model that may work and cost a bit less, is the N- 455V LOC. It too, is adjustable. But I cannot tell what voltage output range you have to work with. It can take up to 50 watts input so that's good... but am not sure what the output voltage range is. Not specified in details.
Comments?
Swez
VRWRX on 10/28/2003 14:51:34
Are you talking about the output voltage of the speaker leads from the stock HU? If that's what you want, I can probably get that info too, it just may take a bit. I'll let you know...
So it sounds like the N-455 can only take up to 50 watts of input. So if my HU puts out more than that per channel I can't use that one? The N-7V doesn't specify a max that it would take, so should I assume it's unlimited? I'm thinking that for only $15 more, it would be worth it to get the better one (N-7V) just to be sure I am not limited and I can make the necessary adjustments. That's the best one on that site, and it's only like $30. I think it's worth $30 so I'm not limited by anything, don't you? I can't thank you enough for all your help, Swez!
Swez on 10/28/2003 19:05:21
A 50 watt input per channel is a lot of power for a car HU amplifier. Most OEM HU's give ~16 watts RMS/ch. In a good Aftermarket model, 24 Watts RMS is the norm. In amplified systems, might be closer to 35 watt/ch... so the N-455V is no slouch either.
Yeah, the N-7V would be my choice too. Good product for your application. Am not sure what the input voltage is, but from what I read, the isolation transformers used and the variable gain are probably such that they can easily take 25 watts per channel, if not more. So, you should be fine on the N-7V.
I really like the variable voltage feature in these products!
Swez
VRWRX on 10/30/2003 09:53:27
Cool, the N-7V it is. Alright, I think I have all the information I need to install my new system the right way. Now I just need to buy all the stuff and do it. Thanks again for your patience and all your help, Swez. I have been trying to get this specific information for a long time, and now I have found it. I'm glad I found this place!!!
Swez on 10/30/2003 11:14:03
Sounds like a plan Stan... this should be a pretty nice install when you are finished. You'll have some real bass at your control and hopefully the mids/highs will be balanced enough not to need much more upgrading. If you want to do that later... we're here to help out.
Appreciate your comments on the other post as well. We all work pretty hard for our readers and (personal) flaming of others, is not our practice here. A few have tried to come here and behave that way, but they get the boot or take the hint and stop the nonsense.
The only thing we need now, are a few more techs... an Electrical Engineer, a Master box maker and maybe a few more generalists. That's my personal wish list... and it would make the load lighter for all and serve our membership very well with that kind of tech HP.
I also wish that our economy would grow as fast as this site has grown since Ferbruary 2003. hehe
Swez
PS Just a thought... that LOC that you are getting soon... would it make sense to tap into the HU wiring harness (rear speaker lines)install that LOC where you can operate it as you drive. This would allow you to adjust bass output (up/down) from the driver's seat and just run a set of RCA's back to the amp, along the opposite rail as your power feed line. You may like that feature on very strong or very weak bass tracks. Gives you instant control of how much bass you want.
Comments?
VRWRX on 10/30/2003 13:12:41
That would be a good idea - similar to the remote gain control I have seen available on the newer amps. It would be a bit more wiring, but I think I could handle it. And I have some empty little filler spots on my center console where I could place the knob. Good thinkin'!
I think my mids and highs should be adequate for what I want to do right now. They sound pretty good (they are upgraded factory speakers), they just need a little more low end. I will eventually upgrade them, though, and I will be right back here asking questions...
Swez on 10/30/2003 19:23:55
Yep, you have the idea right... remote gain control, right at your finger tips. Will give you a feature found on the newer amps and you control the amount of bass in the mix for better SQ or if you wish to show off a bit.... but don't get careless or may blow the sub w/ too much gain.
Swez
Replies (20)
Swez on 10/20/2003 17:35:48
Should be fine if you bridge the amp. In fact, you'll have closer to 400 watts RMS from this amp when bridged... BUT YOU MUST USE A 4 OHM SPEAKER LOAD WHEN BRIDGED.
The Perfect DVC is 2/4/8 ohms, depending on your wiring per each. If you use 2, the DVC is fine. If you only use 1 sub, get the 4 ohm SVC model.
NOTE: If you go lower than 4 ohms to the amp when bridged, it will damage the amp.
http://www.justwoofers.com/Woofer_Pages/Infinity/infinity
_KappaPerfect.htm KAPPA PERFECT12 SALE! $154.99 4 OHMS, SVC
http://www.justwoofers.com/Woofer_Pages/Infinity/infinity
_KappaPerfectDVC.htm 2-INF-KAPPA12.1D TWO INFINITY KAPPA 12.1D SUBWOOFERS SALE! $159.99/ea, $319.99/pr.
Underpowering this sub(s)... nope! Speakers are made to operate in a range of input power. They are rated for max watts (RMS/PEAK) but will operate fine and last longer if you don't run the amp into clipping mode. (high distortion)
Does your present speakers play well at low volume levels? Sure! They sound better when there is adequate power to get them cranking, but low distortion... but still sound fine at 30% of max right? Same for subs.
Swez COFFEE
PS Welcome to the forum... come stay a while and learn. SMILE
Tray on 10/21/2003 13:44:35
What will happen if you underpower the sub, is that the output will be slightly lower.
The problems you have heard are most likely due to abuse of the sub, and clipping issues with the amp. I have run my Perfect 10.1s on as little as 75 watts, and as much as 700 watts.
I wouldn't recommend going any higher than Infinity recommends, unless you have an extremely well built setup, and even then, I would keep it safe.
The main thing you have to remember, is you can't just turn up the gains, and bass boost, and expect your sub to perform that much better. If you have reasonable expectations, and don't try to exceed the limits of your equipment, that combo should be just fine. If it turns out you want/need more output, then an amplifier upgrade would be in order.
I can say that if you build the right box, the Perfects sound amazing.
Swez on 10/21/2003 14:33:40
Well said Tray!
Swez
VRWRX on 10/21/2003 18:09:11
Thanks for the input guys! I am a relative noob to car stereos. I have had systems in my cars, but I have never took the time to actually figure out how to do it right. I just hooked it up and turned up the volume. So please excuse my naiveness with these questions. Is clipping the amps way of saying that it's overworked? How do I keep the amp from clipping? Would I be able to hear the clipping? I have heard other amps go into a sort of "protect" mode, but I don't know that I have actually heard clipping. I know that I have had the gain on this amp turned up all the way with no problems (at least not audible) with my previous speakers (and they were not damaged). I have been trying to do some research on it, and from what I can gather, basically the only thing I can do to prevent clipping is to not have the gain up all the way. But I could be completely wrong. Is that correct? Also, why shouldn't I put a 2 ohm load to the amp? Will that just cause it to run too hot? I know that amp is stable at 2 ohms. Will 4 ohms be safer? Wouldn't it be louder at 2 ohms? Again, thanks for your help and feel free to shoot any of this down if it's incorrect. I'm just trying to learn...
Swez on 10/21/2003 22:50:26
Most 2 channel amps are 2 ohms stable in stereo and deliver more power to the sub(s) on that channel. However, when bridging a 2 channel amp to MONO, you get the most safe power to a 4 ohm load. If you run the amp at 2 ohms in MONO, it will overheat, run the transistors much harder and shorten the life of the amp considerably.
There are High Current (HC) amps that use 2 channels and can be run as low as 1 ohm in MONO, but thes amps are real current hogs and used mostly in high SPL applications. Very expensive too.
Clipping: This is when the input signal waveform is greatly distorted and out of specifications to the amps normal operating parameters. Clipping can be be heard in mid/highs by harsh, shrill and unatural sounding vocals, guitar and cymbals.
Clipping in woofer amps are bit harder to detect. Ususally the bass gets mushy, poor definition and just not crisp.
Here, read this for more details: http://www.eatel.net/~amptech/elecdisc/2ltlpwr.htm
Swez
VRWRX on 10/22/2003 10:02:02
Cool, thanks. Now I understand why I need to run the SVC 4 ohm sub. That makes sense. But after all that, I still don't know how to prevent my amp from clipping. Is there even anything you can do to prevent it?
Swez on 10/22/2003 10:48:16
Proper gain settings on the amp that match the HU output level will prevent the amp form "excessive" clipping. Some amps have a clipping LED indicator. Many do not and you have to either use an O-Scope to detect clipping or your ears/eyes will also tell you when excessive clipping is happening.
Best method w/o an O-Scope:
1. Know where your HU volume setting are starting to distort. (the HU is clipping) Usually, 50-70% of the HU volume max setting is where the HU begins to clip. (the more bass boost on HU is used, the sooner the clipping will begin)
2. Know what the HU RCA output voltage is (2.0 - 6.0 volts is common)
3. Match the amp input gains with your HU output levels. (Ie: if the HU puts out 2.0 volts, set amp gain(s) at 2.0 volts as well)
TIP:
I have found the best way to determine if system is clipping, is to open the doors and crack the truck/hatch a few inches. Then, turn off the sub amp or pull the RCA's for now.
Turn on your system and get out of the car and stand in back of vehicle a few feet and listen carefully. If the full range speakers are full and clean, you're in the safe zone. If you hear shrill, harsh or unatural mids/high... the system is clipping already. Dial back on the HU volume until it is clear and clean.
Now, reconnect the sub amp and listen again. Should hear clear, full & tight bass coming from the subs. If mushy, poorly defined bass is noted, amp gain adjustments may clear it up.
Basically, going from one extreme (high clipping levels) to (low clipping levels) takes patience and a good ear. Getting out of the vehicle and standing away from the car a few feet are the best way to determine if your system is clipping (excess distortions) or running at optimal settings.
Does that help?
Swez
VRWRX on 10/22/2003 13:50:19
Yes, that does help. I guess I'll just have to install it and see what happens. I will be modest with the gain and try to listen carefully for any distortion. I will try the tip you gave to try to see if I can detect anything. Thanks a ton for all your patience and help!
Swez on 10/22/2003 14:24:47
When you run your setup testing, use music material you are very familiar with. This way, you can detect suble/major changes in sound quality.
I think there is an FAQ on this site that talks about "Tweaking your Subs for success." The same principle applies to mids and highs. Basically, use the HU tone controls sparingly to boost bass or highs.(+3dB) is usually enough.
Same thing on sub amp & bass boost... best not to use it at all unless there's a real weakness in bass @ 45 Hz range. Again, a little boost is all that should be used or it may damage your subs.
You'll be fine as we coach you through the details,
Swez
VRWRX on 10/27/2003 17:25:32
OK, so I have one more question. I will be using a Line-Out Converter because I wish to keep my stock HU for the in-dash changer and as a theft deterrent. Will the LOC affect any of this? I have heard good things about the David Navone LOC's,
http://www.davidnavone.com/adaptor_products.htm
but I don't know which one to get (the N-777 or N-7V). What benefit does the variable volt output on the N-7V give me? Is that something I should be concerned with? Are there other LOC's that may suit my needs better?
As a caviot to that, I have the premium sound in my car ('02 Subaru Impreza WRX) with a powered sub under the passenger seat. How will I deal with unhooking that and using the LOC? I'm not sure what kind of wires are run from the deck to the sub under the seat. I know they aren't RCA's, so I would assume they are just speaker wires. So would I just hook up the LOC to the speaker wires running to the sub under the seat? I am a little confused on exactly the LOC's work, so any input would be great. Thanks again!!!
Swez on 10/27/2003 19:47:02
Very good product line you have found. Navone and Clark are two of the top Car Audio engineers in the game.
I have a few questions for you before choosing the right LOC:
1. The stock HU has a powered sub as part of the package now... how many watts does this sub amp feed the present sub?
2. Does you PPI amp have RCA, balanced line or both for inputs?
3. What is the gain range on your PPI amp settings? (250Mv - ? volts)
4. Assume you only want sub signals from the LOC to amp yes?
There are several versions of convertors that you may use for this application. Not sure how many watts you have powering that OEM sub system, so having the ability to attenuate (lower the signal voltage ) to meet amp input needs will help a lot. The N-7V makes sense here and is adjustable. It is full range, and your amp LP filter can do what is needed to get the proper bass range to your sub.
The 2 products mentioned are both full range. You have LP LOC device versions too and one that is adjustable. The only thing I did not like here, is the +12dB bass boost feature @ 40 Hz. Your amp has that already and that much boost can be tough on a sub. The 20 Hz infrasonic filter is appropriate with ported sub designs, but not really needed in a sealed allpication.
The N-85V seem like the best overall choice as it can take amplified signals from factory amps and drop them usable amp input levels. This too, has the +12 dB bass boost feature and SS filter. I would like to see this package modified to have a +3 ~ +6dB variable bass boost... not a fixed+12 dB boost.
You may want to call them and explain your applications and ask them for a best fit LOC. I would!
Swez
Reply to the questions noted and will advise your bets choices OK?
Swez
VRWRX on 10/28/2003 10:17:51
1. I'm not exactly sure how many watts the present sub is getting. I am trying to get the answer. Hopefully I will have it soon.
2. My PPI amp has only RCA inputs.
3. I'm not sure on the gain range of the amp right now. It's currently in storage, so I can't really look at it. If necessary, I can go look, though.
4. Yes, I only want the sub signals from the LOC to the amp.
2 things -
1. My amp is pretty old, and does not have any sort of crossover function. When I had it hooked up previously, I was just using an F-Mod hooked to the RCA's to filter out what I didn't want the subs to see. Just FYI - I don't know if it matters.
2. Couldn't I just tap into the rear speaker leads for the LOC? Then I could just unhook the stock sub, take it out, and not have to worry about those connections. Then I wouldn't have messed with any of that, so if I ever needed to return it back to stock, nothing would have been changed.
VRWRX on 10/28/2003 13:13:45
Update:
I think the sub amp feeds the stock sub 30 watts.
Swez on 10/28/2003 14:03:22
OK, that seems in order and if you have FMods for your inputs to the PPI amp, that is sufficient if in the 80-100 Hz range. (LPF)
If you know the amp model, you may be able to locate the data on same at the PPI site. If it is that old, they may have an archive search so you can locate what you need on the gains. Probably 250Mv - 4.0 volts, may only 2.0 volts... but the adjustable LOC can compensate for that too.
As I think it over a bit more, the N-7V may be your best choice as it has variable output source, full range and you should be able to connect right off the rear full range speakers from the HU amps. You can leave the sub as is, just pull the wires off so when you sell the vehicle, can reconnect all that with minimal effort?
The other model that may work and cost a bit less, is the N- 455V LOC. It too, is adjustable. But I cannot tell what voltage output range you have to work with. It can take up to 50 watts input so that's good... but am not sure what the output voltage range is. Not specified in details.
Comments?
Swez
VRWRX on 10/28/2003 14:51:34
Are you talking about the output voltage of the speaker leads from the stock HU? If that's what you want, I can probably get that info too, it just may take a bit. I'll let you know...
So it sounds like the N-455 can only take up to 50 watts of input. So if my HU puts out more than that per channel I can't use that one? The N-7V doesn't specify a max that it would take, so should I assume it's unlimited? I'm thinking that for only $15 more, it would be worth it to get the better one (N-7V) just to be sure I am not limited and I can make the necessary adjustments. That's the best one on that site, and it's only like $30. I think it's worth $30 so I'm not limited by anything, don't you? I can't thank you enough for all your help, Swez!
Swez on 10/28/2003 19:05:21
A 50 watt input per channel is a lot of power for a car HU amplifier. Most OEM HU's give ~16 watts RMS/ch. In a good Aftermarket model, 24 Watts RMS is the norm. In amplified systems, might be closer to 35 watt/ch... so the N-455V is no slouch either.
Yeah, the N-7V would be my choice too. Good product for your application. Am not sure what the input voltage is, but from what I read, the isolation transformers used and the variable gain are probably such that they can easily take 25 watts per channel, if not more. So, you should be fine on the N-7V.
I really like the variable voltage feature in these products!
Swez
VRWRX on 10/30/2003 09:53:27
Cool, the N-7V it is. Alright, I think I have all the information I need to install my new system the right way. Now I just need to buy all the stuff and do it. Thanks again for your patience and all your help, Swez. I have been trying to get this specific information for a long time, and now I have found it. I'm glad I found this place!!!
Swez on 10/30/2003 11:14:03
Sounds like a plan Stan... this should be a pretty nice install when you are finished. You'll have some real bass at your control and hopefully the mids/highs will be balanced enough not to need much more upgrading. If you want to do that later... we're here to help out.
Appreciate your comments on the other post as well. We all work pretty hard for our readers and (personal) flaming of others, is not our practice here. A few have tried to come here and behave that way, but they get the boot or take the hint and stop the nonsense.
The only thing we need now, are a few more techs... an Electrical Engineer, a Master box maker and maybe a few more generalists. That's my personal wish list... and it would make the load lighter for all and serve our membership very well with that kind of tech HP.
I also wish that our economy would grow as fast as this site has grown since Ferbruary 2003. hehe
Swez
PS Just a thought... that LOC that you are getting soon... would it make sense to tap into the HU wiring harness (rear speaker lines)install that LOC where you can operate it as you drive. This would allow you to adjust bass output (up/down) from the driver's seat and just run a set of RCA's back to the amp, along the opposite rail as your power feed line. You may like that feature on very strong or very weak bass tracks. Gives you instant control of how much bass you want.
Comments?
VRWRX on 10/30/2003 13:12:41
That would be a good idea - similar to the remote gain control I have seen available on the newer amps. It would be a bit more wiring, but I think I could handle it. And I have some empty little filler spots on my center console where I could place the knob. Good thinkin'!
I think my mids and highs should be adequate for what I want to do right now. They sound pretty good (they are upgraded factory speakers), they just need a little more low end. I will eventually upgrade them, though, and I will be right back here asking questions...
Swez on 10/30/2003 19:23:55
Yep, you have the idea right... remote gain control, right at your finger tips. Will give you a feature found on the newer amps and you control the amount of bass in the mix for better SQ or if you wish to show off a bit.... but don't get careless or may blow the sub w/ too much gain.
Swez
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