I just had an map installed, and was curious on how to adjust on the amp to give more power to the front speakers to get better all-around sound. I have a 4-channel amp attached to all four of my speakers. It has a gain for channels 1 and 2, and a gain for channels 3 and 4. There's also the high and low pass adjustsments as well. I'm not sure how these things work exactly and how they will effect the sound. I don't want to do and harm to my speakers so I thought I'd ask before I do anything.
Replies (13)
alanjlamore on 10/27/2004 15:42:23
Well, one way to make sure you're not causing any clipping of your speakers (very bad for them) is to turn both gains down all the way (so there's almost no sound), then set your head-unit to the maximum volume you're going to listen to it (usually a little less than full volume, you should still only barely hear anything from speakers).
Gradually increase the gain for the front speakers untill they're loud, but without distortion. Some people go to were you hear a little distortion and turn it back a tiny bit.
Then with your gain set for the front speakers you can temporarily unplug the RCAs from the amp and do the same for the rear speaker's gain.
Once they are set, you can adjust the rear gain again (only adjusting lower) with everything plugged in to get the balance you're looking for between the front and back.
alanjlamore on 10/27/2004 15:44:48
Oh yea, one more thing is that it's easier to listen for distortion with your car doors open and standing about 10 feet away. That makes a small amount of distortion more noticeable.
This means you'd have to increase the gain little by little, and step back from the car to listen for distortion. Takes longer, but worth it.
Intrigue on 10/27/2004 15:55:55
Thanks for your help. I'll give it try and tell you how things work out.
Intrigue on 10/27/2004 16:04:45
Well, I gave it a try but something very interesting happens. When I lowered both of the gains for all the channels, I could still hear the volume from the rear, but it was a quieter. When I turned the gain up for the front speakers, the rear speakers got louder, and when I turned the gain for the rear speakers the rears speaker got even louder. The front speakers showed no change at all. I'm thinking I'll have to take it back to the installer and ask them what's going on.
alanjlamore on 10/27/2004 16:54:24
Are you sure you only adjusted both gains? I've made the mistake of accidentally adjusting a high or low pass filter knob instead of a gain knob.
My amp had a gain and a high/low pass filter right next to eachother on each side of it.
Otherwise, if you know you only adjusted the gains, the place might not have installed it right......
uochronos on 10/27/2004 17:10:14
do not turn the gain up past where it should be! this is just asking for trouble. adjust the rear gain down is ok but adjusting the front one up higher well only cause clipping. the gain should be set at the same voltage as your HU's outputs or less. if you have 2volt preouts dont set your gain below 2volts setting it say at 1volt would cuase alot of clipping and damage to speakers.
the way stated above to adjust well work just be carefull not to turn it up past 2 volt or what ever your HU outputs.
Chronos
Intrigue on 10/27/2004 20:51:52
Yeah, my gain's are right next to my high and low pass too, but I was sure to adjust the right ones. I'm also being very cautious not to turn the gain up too high, and in fact that's the reason I'll wait and let the installer do it.
Something else that may go into consideration is that they had to use a Y-connector for my RCA outputs on my stereo. I'm not sure if that could be a part of the problem. It's a cheaper stereo, and that's why I'll be upgrading it soon. I'll put in the new stereo and then see how things work out.
alanjlamore on 10/27/2004 21:48:37
I bet that's why. I don't know what they did, but I'm sure they'll be able to explain it to you and tell you where the signal is coming from and going to.
Smart to let them do the gain adjusting 'till you know how they wired it.
Good luck!
Intrigue on 12/27/2004 21:17:17
Sorry for the late update, but I found the problem here. The speaker wire leading out of the amp to the speakers were connected to the amp in the wrong order... If I remember right, channels 3 and 1 were switched so you can imagine my confusion when adjusting the amp. I wasn't too happy about that, but it was a easy fix. Other than that the dealer did a good job installing the amp, but a simple mistake like that makes me worry.
swez on 12/27/2004 21:45:37
Alan mentioned setting the HU volume close to max and then adjust your amp gains to the loudest point you can get, w/o distortion. I have found that HU's can begin to clip (excess distortion) at <75% of max volume. Especially if we use bass boost, loudness contours or excessive EQ.
1. Set amp gains to 4.0 volts or higher
2. Set all tone controls on HU to "flat" ("0" boost/cut)
3. Set HU volume between 50-60% of max
4. Bring up amp gains for front speakers until you hear distortion, back off on gain til it's gone
5. Bring up rear channel amp gains until you get the staging you like best. (usually a few dB less SPL in back)
As Alan mentioned, open the doors and walk back ~10 feet and listen for shrill highs, muddy mids and lows. This tells us we are clipping the amp. To be sure you are not clipping front or rear channels, adjust them separately, then blend. (adjust rear speakers w/ trunk closed)
Also, setting the HP filters properly, depends on the speakers used. Small format speakers (<5" MB) start at 250 Hz and work you way down until speakers are clean and adequate SPL. If the MR speakers get sloppy, dial up the HPF until it is clean again and/or readjust amp gains. (80-100 Hz range is fine for most 5-6" MR drivers)
Rear speakers like 6.5" rounds, 6x9 ovals will often go a bit lower than 80 Hz., and still sound clean and solid. Smaller formats like 4", 4x6", 5x7" & 6x8" will often get sloppy below 80 Hz., as we put more power to them. Clarity and decent SPL matching are the goal here.
Also, that install foul up would bother me too. That's why we advocate a DIY mentality whenever possible. That way, we know what was done, where the wires are and can do a better job at diagnostics and troubleshooting problems.
Finally, you mentioned the installer used "Y" splitters here? Did the HU only have 1 pair of RCA's? If that was the case, not an unusual way to get 4 channels of audio from a 2 channel RCA HU. However, if the HU has 2 or more pairs of RCA's, he took a shortcut to save time and money on installing extra RCA cable sets. (more profit to the installer's boss by cutting corners)
Some amps (Alpine for one) have a great pre-amp system to help deliver 4-5 channels of signal when there are only 1 pair of RCA's available. The only real issue, lacking fade control at the HU. Can compensate for this with proper gain setting techniques as noted above... but no HU fade functions this way.
Comments?
Swez
Intrigue on 12/27/2004 22:40:35
They did mention to me the problems of using the Y cables, and I did replace the HU right after with the panasonic. My old HU was a cheap one, and I overlooked all the compatibility issues. Although if anyone ever wants just a CD player in their car, suggest the Pioneer DEH-1600. An excellent receiver for the price.
http://www.discountsjungle.com/pacq3dam.html
Like you said, I think I will work on all of my own installations from now on. You guys have never steered me wrong so I can always some here for help.
Ever since I got the amp I have been making tons of adjustments to get the sound I was looking for. Right now I have it set just where I want it. There is very little distortion except for a few songs that deliver deep powerful bass, which my rear speakers don't seem to like in a sense. I used the HPF to make less rattle and distortion from the smaller front speakers and I have been relying on the rear speakers for the bass. I tried using the low pass for the rear speakers but I wasn't happy with the sound. My system is sounding good right now but I'm planning on adding a sub soon and dynamat to finish it off. Hopefully the dynamat will help the rear speakers handle the bass better, allow me to add a little more bass to the front speakers, and we'll see how my trunk takes the sub when I install it.
MrBrownstone on 12/28/2004 01:53:57
If you are using a Factory HU, try not to use it above ~80% to 90% of it's maximum volume. Most of those units have an anticlip volume control that cut your bass output to avoid the HU from clipping.
This however won't protect any other part of your system from being overdriven.
On an aftermarket unit, you can use 100% of it's volume control...but should probably gain it to 95% for those low output CDs.
Intrigue on 12/28/2004 03:54:00
Thank you for the advice. I wouldn't have thought that the HU volume made such a difference when having a amp, but apparently it does. I have an aftermarket and I'll be sure to make the proper adjustments if needed.
My volume ranges from 0-40, and I usually listen to on average 30, which is pretty loud, and when I really want to crank it I put it up to 34 to 36. At that point it still comes in clear, it seems that my speakers shouldn't take much more (not to mention my ears), especially if I want more bass. Like I mentioned to swez, I'm going to need a sub to get more bass out of my system. We had a long talk about that.
Replies (13)
alanjlamore on 10/27/2004 15:42:23
Well, one way to make sure you're not causing any clipping of your speakers (very bad for them) is to turn both gains down all the way (so there's almost no sound), then set your head-unit to the maximum volume you're going to listen to it (usually a little less than full volume, you should still only barely hear anything from speakers).
Gradually increase the gain for the front speakers untill they're loud, but without distortion. Some people go to were you hear a little distortion and turn it back a tiny bit.
Then with your gain set for the front speakers you can temporarily unplug the RCAs from the amp and do the same for the rear speaker's gain.
Once they are set, you can adjust the rear gain again (only adjusting lower) with everything plugged in to get the balance you're looking for between the front and back.
alanjlamore on 10/27/2004 15:44:48
Oh yea, one more thing is that it's easier to listen for distortion with your car doors open and standing about 10 feet away. That makes a small amount of distortion more noticeable.
This means you'd have to increase the gain little by little, and step back from the car to listen for distortion. Takes longer, but worth it.
Intrigue on 10/27/2004 15:55:55
Thanks for your help. I'll give it try and tell you how things work out.
Intrigue on 10/27/2004 16:04:45
Well, I gave it a try but something very interesting happens. When I lowered both of the gains for all the channels, I could still hear the volume from the rear, but it was a quieter. When I turned the gain up for the front speakers, the rear speakers got louder, and when I turned the gain for the rear speakers the rears speaker got even louder. The front speakers showed no change at all. I'm thinking I'll have to take it back to the installer and ask them what's going on.
alanjlamore on 10/27/2004 16:54:24
Are you sure you only adjusted both gains? I've made the mistake of accidentally adjusting a high or low pass filter knob instead of a gain knob.
My amp had a gain and a high/low pass filter right next to eachother on each side of it.
Otherwise, if you know you only adjusted the gains, the place might not have installed it right......
uochronos on 10/27/2004 17:10:14
do not turn the gain up past where it should be! this is just asking for trouble. adjust the rear gain down is ok but adjusting the front one up higher well only cause clipping. the gain should be set at the same voltage as your HU's outputs or less. if you have 2volt preouts dont set your gain below 2volts setting it say at 1volt would cuase alot of clipping and damage to speakers.
the way stated above to adjust well work just be carefull not to turn it up past 2 volt or what ever your HU outputs.
Chronos
Intrigue on 10/27/2004 20:51:52
Yeah, my gain's are right next to my high and low pass too, but I was sure to adjust the right ones. I'm also being very cautious not to turn the gain up too high, and in fact that's the reason I'll wait and let the installer do it.
Something else that may go into consideration is that they had to use a Y-connector for my RCA outputs on my stereo. I'm not sure if that could be a part of the problem. It's a cheaper stereo, and that's why I'll be upgrading it soon. I'll put in the new stereo and then see how things work out.
alanjlamore on 10/27/2004 21:48:37
I bet that's why. I don't know what they did, but I'm sure they'll be able to explain it to you and tell you where the signal is coming from and going to.
Smart to let them do the gain adjusting 'till you know how they wired it.
Good luck!
Intrigue on 12/27/2004 21:17:17
Sorry for the late update, but I found the problem here. The speaker wire leading out of the amp to the speakers were connected to the amp in the wrong order... If I remember right, channels 3 and 1 were switched so you can imagine my confusion when adjusting the amp. I wasn't too happy about that, but it was a easy fix. Other than that the dealer did a good job installing the amp, but a simple mistake like that makes me worry.
swez on 12/27/2004 21:45:37
Alan mentioned setting the HU volume close to max and then adjust your amp gains to the loudest point you can get, w/o distortion. I have found that HU's can begin to clip (excess distortion) at <75% of max volume. Especially if we use bass boost, loudness contours or excessive EQ.
1. Set amp gains to 4.0 volts or higher
2. Set all tone controls on HU to "flat" ("0" boost/cut)
3. Set HU volume between 50-60% of max
4. Bring up amp gains for front speakers until you hear distortion, back off on gain til it's gone
5. Bring up rear channel amp gains until you get the staging you like best. (usually a few dB less SPL in back)
As Alan mentioned, open the doors and walk back ~10 feet and listen for shrill highs, muddy mids and lows. This tells us we are clipping the amp. To be sure you are not clipping front or rear channels, adjust them separately, then blend. (adjust rear speakers w/ trunk closed)
Also, setting the HP filters properly, depends on the speakers used. Small format speakers (<5" MB) start at 250 Hz and work you way down until speakers are clean and adequate SPL. If the MR speakers get sloppy, dial up the HPF until it is clean again and/or readjust amp gains. (80-100 Hz range is fine for most 5-6" MR drivers)
Rear speakers like 6.5" rounds, 6x9 ovals will often go a bit lower than 80 Hz., and still sound clean and solid. Smaller formats like 4", 4x6", 5x7" & 6x8" will often get sloppy below 80 Hz., as we put more power to them. Clarity and decent SPL matching are the goal here.
Also, that install foul up would bother me too. That's why we advocate a DIY mentality whenever possible. That way, we know what was done, where the wires are and can do a better job at diagnostics and troubleshooting problems.
Finally, you mentioned the installer used "Y" splitters here? Did the HU only have 1 pair of RCA's? If that was the case, not an unusual way to get 4 channels of audio from a 2 channel RCA HU. However, if the HU has 2 or more pairs of RCA's, he took a shortcut to save time and money on installing extra RCA cable sets. (more profit to the installer's boss by cutting corners)
Some amps (Alpine for one) have a great pre-amp system to help deliver 4-5 channels of signal when there are only 1 pair of RCA's available. The only real issue, lacking fade control at the HU. Can compensate for this with proper gain setting techniques as noted above... but no HU fade functions this way.
Comments?
Swez
Intrigue on 12/27/2004 22:40:35
They did mention to me the problems of using the Y cables, and I did replace the HU right after with the panasonic. My old HU was a cheap one, and I overlooked all the compatibility issues. Although if anyone ever wants just a CD player in their car, suggest the Pioneer DEH-1600. An excellent receiver for the price.
http://www.discountsjungle.com/pacq3dam.html
Like you said, I think I will work on all of my own installations from now on. You guys have never steered me wrong so I can always some here for help.
Ever since I got the amp I have been making tons of adjustments to get the sound I was looking for. Right now I have it set just where I want it. There is very little distortion except for a few songs that deliver deep powerful bass, which my rear speakers don't seem to like in a sense. I used the HPF to make less rattle and distortion from the smaller front speakers and I have been relying on the rear speakers for the bass. I tried using the low pass for the rear speakers but I wasn't happy with the sound. My system is sounding good right now but I'm planning on adding a sub soon and dynamat to finish it off. Hopefully the dynamat will help the rear speakers handle the bass better, allow me to add a little more bass to the front speakers, and we'll see how my trunk takes the sub when I install it.
MrBrownstone on 12/28/2004 01:53:57
If you are using a Factory HU, try not to use it above ~80% to 90% of it's maximum volume. Most of those units have an anticlip volume control that cut your bass output to avoid the HU from clipping.
This however won't protect any other part of your system from being overdriven.
On an aftermarket unit, you can use 100% of it's volume control...but should probably gain it to 95% for those low output CDs.
Intrigue on 12/28/2004 03:54:00
Thank you for the advice. I wouldn't have thought that the HU volume made such a difference when having a amp, but apparently it does. I have an aftermarket and I'll be sure to make the proper adjustments if needed.
My volume ranges from 0-40, and I usually listen to on average 30, which is pretty loud, and when I really want to crank it I put it up to 34 to 36. At that point it still comes in clear, it seems that my speakers shouldn't take much more (not to mention my ears), especially if I want more bass. Like I mentioned to swez, I'm going to need a sub to get more bass out of my system. We had a long talk about that.
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