new Kenwood amp overheating
05-02-2003, 04:17 PM
#1
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new Kenwood amp overheating
I picked up a Kenwood KAC-7201 2 Channel Car Amp (800w) for $200 local. After I wired it up, it sounded a helluvalot better than my old pyrimid amp I had in its place temporarily (obviously).
but its overheating.
I'm powering 2 pioneer 12's in a bandpass box. The subs are 4 ohm. I have them wired in bridged, positves and negatives tied togeather (parallel, I guess).
here's the important specs on the amp:
2 channel 150W x 2
2 channel 230W x 2
Bridged 460W x 1
2 ohm Stable
Stereo, Mono Operation Tri-mode
I have the gains/cutoffs turned all the way up, but I do that so I can use my sub gain adjuster on my headunit (pioneer 6400). Maybe thats where the problem may lie.
regardless, I usually cruse with my seats and windows down, so air is getting back there. But the weather here is kinda hot, too.
I dunno, any ideas?
but its overheating.
I'm powering 2 pioneer 12's in a bandpass box. The subs are 4 ohm. I have them wired in bridged, positves and negatives tied togeather (parallel, I guess).
here's the important specs on the amp:
2 channel 150W x 2
2 channel 230W x 2
Bridged 460W x 1
2 ohm Stable
Stereo, Mono Operation Tri-mode
I have the gains/cutoffs turned all the way up, but I do that so I can use my sub gain adjuster on my headunit (pioneer 6400). Maybe thats where the problem may lie.
regardless, I usually cruse with my seats and windows down, so air is getting back there. But the weather here is kinda hot, too.
I dunno, any ideas?
05-02-2003, 04:32 PM
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When you bridge your amp, your amplifier sees an equivilant of twice the resistance (half the ohms).
Therefore, when you bridge your amp, instead of being 2 ohms stable, it becomes 4 ohms stable. The way you are running your speakers is pretty hard on the amp, and it won't be working to the efficiency it should.
You should run the left channel of the amp to one speaker, and the right to another. This should be more than enough power (and clean power) to take your subs to maximum excursion, and your damping factor goes up too, resulting in tighter, cleaner bass.
Having the same signal going to each speaker is critical if your speakers are sharing the front or the rear chambers of the bandpass box. Fortunately, your pioneer headunit has a sub output, and I'm sure it is in mono. Differing signals would create too much stress on the speakers, and possibly damage them.
T
Therefore, when you bridge your amp, instead of being 2 ohms stable, it becomes 4 ohms stable. The way you are running your speakers is pretty hard on the amp, and it won't be working to the efficiency it should.
You should run the left channel of the amp to one speaker, and the right to another. This should be more than enough power (and clean power) to take your subs to maximum excursion, and your damping factor goes up too, resulting in tighter, cleaner bass.
Having the same signal going to each speaker is critical if your speakers are sharing the front or the rear chambers of the bandpass box. Fortunately, your pioneer headunit has a sub output, and I'm sure it is in mono. Differing signals would create too much stress on the speakers, and possibly damage them.
T
05-02-2003, 04:36 PM
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Originally posted by acurabrothers
When you bridge your amp (mono), your amplifier sees an equivilant of twice the resistance (half the ohms).
Therefore, when you bridge your amp, instead of being 2 ohms stable, it becomes 4 ohms stable. The way you are running your speakers is pretty hard on the amp, and it won't be working to the efficiency it should.
If there is a mono switch on the amp (not bridged, mono), then run one speaker of each channel. This should be more than enough power (and clean power) to take your subs to maximum excursion.
When you bridge your amp (mono), your amplifier sees an equivilant of twice the resistance (half the ohms).
Therefore, when you bridge your amp, instead of being 2 ohms stable, it becomes 4 ohms stable. The way you are running your speakers is pretty hard on the amp, and it won't be working to the efficiency it should.
If there is a mono switch on the amp (not bridged, mono), then run one speaker of each channel. This should be more than enough power (and clean power) to take your subs to maximum excursion.
Having the same signal going to each speaker is critical if your speakers are sharing the front or the rear chambers of the bandpass box. Differing signals would create too much stress on the speakers, and possibly damage them.
bottom line:
So with a mono switch, I can run it non-bridged?
05-02-2003, 04:38 PM
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sorry bout the updates there...
Your deck most likely has a mono sub output (99%).
It is more than safe to simply run left to one, right to the other.
Your deck most likely has a mono sub output (99%).
It is more than safe to simply run left to one, right to the other.
05-02-2003, 04:45 PM
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The only issue here is whether or not you will get enough power to your speakers. It depends completely on how your box is designed for your speakers. One bandpass may only require 80 watts to operate at max efficiency, while another could require 450 - with the same speakers! (Most people don't grasp this concept)
So see what's right for you.
One more concern.
The #1 cause of speaker failure is distortion/clipping.
You are more likely to kill a speaker by using a small amp and
driving it to the limit than by having an amp way too big for the
speaker. With too much power, you will hear a speaker bottom
out, but with too little (and especially with a bandpass) it is
difficult to detect small amounts of clipping = heat build up in the
voice coil and ultimately destruction.
Enough insight for ya!?!?
So see what's right for you.
One more concern.
The #1 cause of speaker failure is distortion/clipping.
You are more likely to kill a speaker by using a small amp and
driving it to the limit than by having an amp way too big for the
speaker. With too much power, you will hear a speaker bottom
out, but with too little (and especially with a bandpass) it is
difficult to detect small amounts of clipping = heat build up in the
voice coil and ultimately destruction.
Enough insight for ya!?!?
05-03-2003, 03:11 AM
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Based on the description of how you have your subwoofers wired to your Kenwood amplifier, you are trying to run your amp at 2 ohm mono. That amp will work at that impedance but not for long and not at a cool operating temperature as you are experiencing. The solution to your problem would be to either unbridge your amplifier and wire the subs at 4 ohm stereo or get a different amp that will be capable of running a 2 ohm mono load.
05-03-2003, 11:45 AM
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Originally posted by acurabrothers
The only issue here is whether or not you will get enough power to your speakers. It depends completely on how your box is designed for your speakers. One bandpass may only require 80 watts to operate at max efficiency, while another could require 450 - with the same speakers! (Most people don't grasp this concept)
The only issue here is whether or not you will get enough power to your speakers. It depends completely on how your box is designed for your speakers. One bandpass may only require 80 watts to operate at max efficiency, while another could require 450 - with the same speakers! (Most people don't grasp this concept)
isn't the biggest factor having subs that are good for the box, and then having enough space for the subs?
The #1 cause of speaker failure is distortion/clipping.
You are more likely to kill a speaker by using a small amp and
driving it to the limit than by having an amp way too big for the
speaker. With too much power, you will hear a speaker bottom
out, but with too little (and especially with a bandpass) it is
difficult to detect small amounts of clipping = heat build up in the
voice coil and ultimately destruction.
You are more likely to kill a speaker by using a small amp and
driving it to the limit than by having an amp way too big for the
speaker. With too much power, you will hear a speaker bottom
out, but with too little (and especially with a bandpass) it is
difficult to detect small amounts of clipping = heat build up in the
voice coil and ultimately destruction.
Originally posted by Randy12vp
Based on the description of how you have your subwoofers wired to your Kenwood amplifier, you are trying to run your amp at 2 ohm mono. That amp will work at that impedance but not for long and not at a cool operating temperature as you are experiencing.
Based on the description of how you have your subwoofers wired to your Kenwood amplifier, you are trying to run your amp at 2 ohm mono. That amp will work at that impedance but not for long and not at a cool operating temperature as you are experiencing.
The solution to your problem would be to either unbridge your amplifier and wire the subs at 4 ohm stereo or get a different amp that will be capable of running a 2 ohm mono load.
