I am having a very annoying problem with a newly installed system. I have a Panasonic CQ-C5410 deck with 2 sets of Infinity Kappa 60.5CS in my front and rear doors. These are powered by a Sony XM-460GTX amp. When I turn the gain up a bit and add a llittle volume the amp shuts of and I have to cycle power on the deck to get it back on. The speakers are not load at all. Any ideas what could be causing this? I have already verified 4 OHms at the crossover and there is no short in my speaker run.
Thanks,
-Lance
Replies (16)
swez on 05/13/2004 09:26:24
When you dial back on the amp gains, (high sensitivity) the amp gets too much input signal and goes into overload. The amp detects that overload and shuts down to protect itself.
Go back and look at your HU specs for the RCA preout voltage. The amp gain settings should be matched to that number +/- 10%. Also, avoid using large amounts of bass boost on the HU or the amp as this will make the amp clip (excess distortion) and drive your speakers too hard. Set your HPF (high pass filters) on each amp channel to ~60 Hz for now. This should help the amp play louder w/o shutting down.
If you desire more bass in your system, consider adding a sub and amp to the system. That will make a big difference and not work your speakers and 4 channel amp pull double duty as well.
Swez
pmpn8ez on 05/14/2004 00:11:07
Thanks Swez:
I have my HPF set to 90Hz. I have two Infinity Perfect 12's for my lows, running off a seperate amp, I guess I should of had that in there. My RCA preamp outputs are 5V, so the gain should be at 5???, I also have the HPF on and set to 60Hz (Just in case my EQ should fail)
pmpn8ez on 05/14/2004 00:27:30
I just tried the level set at about 5 (which is all the way down) and I can grab a handful without the amp shutting down, but the volume is super low...think I'd need a bigger amp? I was under the impression that turning up the level control increased the Watts out. The Kappas are rated for 60W RMS and the amp is rated at 60 X 4 RMS, but I'm guessing that's with the level all the way up...at .3V . Am I right? Is there a place to lean about all this?
-Thanks Again.
ttocs on 05/14/2004 02:10:05
don't look at the numbers. I have been installing for years and have no idea what the numbers around the gain are...
put in a clean cd that you are familiar with. Turn the gain on the amp all the way down, turn the deck up to 3/4 - 2/3 max valume. Now Slowly adj the amp gain up until the sound is just starting to distort. Done.....
Do this with all bass and treble controls at a nuetral position. If it is still not loud enough, or the gian of the amp is all the way up, then you need a better amp..
pmpn8ez on 05/15/2004 14:27:10
TTOCS:
That's the problem, when I turn the amp up it shuts down, but the speakers aren't even close to distorting. Could it be that with the gain up, the amp begins clipping and the speakers notice the clipping and are making the amp shut down? If I keep the gain around 5 (to match my preamp output as swez mentioned) I can crank it up, but it's not loud enough...but the amp shuts down. So either the the speakers are quite...wiring is good so it's possible I just need a bigger amp?
swez on 05/15/2004 19:31:02
You may need to check your speakers fed off the amp. If there is a minor short in these wires (+ spade lug touching grounded metal on door etc.) The amp will detect that ultra-low ohm load and shut off. This is a circuit protection device built into most amps.
An Ohmeter is the best tool for testing the resistance on each line to your speakers. It each line is ~4.0 ohms... you have a good install. If one or more speaker lines is well under 2 ohms, that circuit is in trouble and may be the root of your problem here. You can buy a small, but useful meter at WalMart for under $20.00. This tool will be handy for a long time.
Once you have checked the ohmic readings off each speaker line, then we can help you figure out what to do about the amp settings to get more output from this amp. Ttocs is right on about setting the amp gains by ear, to get the most clean output from the amp.
Oh... what gage wire are you using to feed this amp power? It's rated at 50A max draw before the fuses trip, so # 8 is adequate here.
Swez
PS Since these are Comps, there may be a difference in ohmic load readings from the speaker wires. The crossovers alter impedence reading from the filters. How did you mount the crossovers so they do not short out or get wet when installed?
pmpn8ez on 05/16/2004 15:44:28
SWEZ:
Thanks, I have a multimeter and it's a good 4Ohm load. I mounted the x-over under my door panel. I am using 4 Gauge from my battery to the Amp, into a dist. block and 2 feet of 8 Gauge into the amp. * gauge grounding cable, 2 feet to my seat mounting bolts. I have also checked the speaker wires for a reference to ground (there is none)
ttocs on 05/16/2004 16:14:01
sounds like it could be a bad amp possibly. Take it to a local shop and have them bench test it.........
swez on 05/16/2004 18:58:54
That ground you have... it must be to a bare metal surface to work properly. If there is paint or rust at that grounding bolt, the ground will not be a true ground and may cause the amp to react this way. Use a crimp on "eye" style connector as bare wire can sometimes lose connectivity and result in a poorly grounded amp.
Everything you mentioned on wiring sounds good otherwise. The speakers being 4 ohms is good and speaker ground is not the same potential as "reference ground" such as chassis, body or BAT (neg). HU's and amplifiers use an "isolated floating ground" system. It does not correlate to car grounding systems.
Finally, as ttocs said... the gain control setting marks on the amp, are not always accurate. Use the technique he outlined until you get the best performance possible on this amp. If your amp keeps cutting out, you may wish to get a better amp.
Swez
pmpn8ez on 05/30/2004 23:06:18
Alright...the problem with the amp was that the gain was set too high and was clipping. The clipping signal reaching the speakers caused the amp to shut off. I bought a larger amp and set the gain to match my HU output voltage (5) and I can now grab a handful and make ears bleed without the amp cutting off. Thanks everyone for you're help,
swez on 05/31/2004 09:02:42
Good job PmP,
What amp did you buy?
Swez
pmpn8ez on 05/31/2004 12:20:06
I went with a Polk Audio C400.4 to push both sets of Kappa 60.5CS's...Sony sucks!!! Any ideas on a good mono amp that'll run good at 1 Ohm?...I've been looking at getting another set of 12's...the polk amp really kicked up the highs and there doesn't seem to be enough bass now ;)
One other question...any good sites that detail making custom boxes...using fiberglass? Thanks again for all your help.
-Lance
swez on 06/1/2004 11:29:39
Lance,
Nice choice on amps... Polk makes great speakers and I am sure their amps are also top notch. Have owned Polks for HT many years and never had a failure. Still using them 25 years later and they are very accurate.
As for box making in fiberglass, messy job here friend. Here's a primer on the subject: http://www.bcae1.com/fibrglas.htm
As for sub amps that are 1 ohm stable, there are a few out there in Class D versions. The other option is "HIGH CURRENT" (HC) amps which are often 2 channel. The "HC" amps are great for potent bass, but suck a lot of juice from the electricals. This HC style of amp is generally ~60% efficient. Class D amps are closer to 90% efficiency levels.
How much power do you think you'll need here for bass? Any thoughts on the subs you wish to use? I usually suggest about 8:1 ratio.... meaning, 800 watts for subs to every 100 watts for interior speakers. Yes, can go with a smaller ratio, but avoid less than 5:1 to keep your bass clean and distortion free.
Comments?
Swez
pmpn8ez on 06/2/2004 00:42:32
Swez/ALCON:
Whatta think of this amp?
http://www.kenwoodusa.com/product/product.jsp?productTypeId=11&sortBy=price&productId=2424
I can get it at the BX...A military store for under $300.00
swez on 06/2/2004 11:17:16
Not a bad amp here Lance. If you cut through all the specs jargon, looks like this amp will deliver ~800 RMS to a 2 ohm load, 1000 watts RMS @ 1 ohm. Not bad features and the price is very good as well. I would assume this amp is set up for #4 gage power wire and is fused by 3x25A or so. (not stated in web page specs though.)
OK, what subs to use? A pair of DVC (4+4) in full parallel will net a 1 ohm load for this amp. You may need to use #2 power wire here to supply enough current to both amps.
Swez
PS Amp specs and install manual:
ftp://docs.kenwoodusa.com/manuals/OM-KAC-X810D-2002-KUSA.pdf
pmpn8ez on 06/2/2004 18:09:26
Swez...hanks for the docs.
I already have two Infinity Kappa 120.1se and was just thinking of adding 2 more to drop it down to 1 Ohm...300W RMS each so 1200 for all 4...think the 1000W would be able to do the trick...could I run the Sony amp into the kenwood to boost? not to sure how the RCA out of one amp and into another works.?
Thanks,
-Lance
Thanks,
-Lance
Replies (16)
swez on 05/13/2004 09:26:24
When you dial back on the amp gains, (high sensitivity) the amp gets too much input signal and goes into overload. The amp detects that overload and shuts down to protect itself.
Go back and look at your HU specs for the RCA preout voltage. The amp gain settings should be matched to that number +/- 10%. Also, avoid using large amounts of bass boost on the HU or the amp as this will make the amp clip (excess distortion) and drive your speakers too hard. Set your HPF (high pass filters) on each amp channel to ~60 Hz for now. This should help the amp play louder w/o shutting down.
If you desire more bass in your system, consider adding a sub and amp to the system. That will make a big difference and not work your speakers and 4 channel amp pull double duty as well.
Swez
pmpn8ez on 05/14/2004 00:11:07
Thanks Swez:
I have my HPF set to 90Hz. I have two Infinity Perfect 12's for my lows, running off a seperate amp, I guess I should of had that in there. My RCA preamp outputs are 5V, so the gain should be at 5???, I also have the HPF on and set to 60Hz (Just in case my EQ should fail)
pmpn8ez on 05/14/2004 00:27:30
I just tried the level set at about 5 (which is all the way down) and I can grab a handful without the amp shutting down, but the volume is super low...think I'd need a bigger amp? I was under the impression that turning up the level control increased the Watts out. The Kappas are rated for 60W RMS and the amp is rated at 60 X 4 RMS, but I'm guessing that's with the level all the way up...at .3V . Am I right? Is there a place to lean about all this?
-Thanks Again.
ttocs on 05/14/2004 02:10:05
don't look at the numbers. I have been installing for years and have no idea what the numbers around the gain are...
put in a clean cd that you are familiar with. Turn the gain on the amp all the way down, turn the deck up to 3/4 - 2/3 max valume. Now Slowly adj the amp gain up until the sound is just starting to distort. Done.....
Do this with all bass and treble controls at a nuetral position. If it is still not loud enough, or the gian of the amp is all the way up, then you need a better amp..
pmpn8ez on 05/15/2004 14:27:10
TTOCS:
That's the problem, when I turn the amp up it shuts down, but the speakers aren't even close to distorting. Could it be that with the gain up, the amp begins clipping and the speakers notice the clipping and are making the amp shut down? If I keep the gain around 5 (to match my preamp output as swez mentioned) I can crank it up, but it's not loud enough...but the amp shuts down. So either the the speakers are quite...wiring is good so it's possible I just need a bigger amp?
swez on 05/15/2004 19:31:02
You may need to check your speakers fed off the amp. If there is a minor short in these wires (+ spade lug touching grounded metal on door etc.) The amp will detect that ultra-low ohm load and shut off. This is a circuit protection device built into most amps.
An Ohmeter is the best tool for testing the resistance on each line to your speakers. It each line is ~4.0 ohms... you have a good install. If one or more speaker lines is well under 2 ohms, that circuit is in trouble and may be the root of your problem here. You can buy a small, but useful meter at WalMart for under $20.00. This tool will be handy for a long time.
Once you have checked the ohmic readings off each speaker line, then we can help you figure out what to do about the amp settings to get more output from this amp. Ttocs is right on about setting the amp gains by ear, to get the most clean output from the amp.
Oh... what gage wire are you using to feed this amp power? It's rated at 50A max draw before the fuses trip, so # 8 is adequate here.
Swez
PS Since these are Comps, there may be a difference in ohmic load readings from the speaker wires. The crossovers alter impedence reading from the filters. How did you mount the crossovers so they do not short out or get wet when installed?
pmpn8ez on 05/16/2004 15:44:28
SWEZ:
Thanks, I have a multimeter and it's a good 4Ohm load. I mounted the x-over under my door panel. I am using 4 Gauge from my battery to the Amp, into a dist. block and 2 feet of 8 Gauge into the amp. * gauge grounding cable, 2 feet to my seat mounting bolts. I have also checked the speaker wires for a reference to ground (there is none)
ttocs on 05/16/2004 16:14:01
sounds like it could be a bad amp possibly. Take it to a local shop and have them bench test it.........
swez on 05/16/2004 18:58:54
That ground you have... it must be to a bare metal surface to work properly. If there is paint or rust at that grounding bolt, the ground will not be a true ground and may cause the amp to react this way. Use a crimp on "eye" style connector as bare wire can sometimes lose connectivity and result in a poorly grounded amp.
Everything you mentioned on wiring sounds good otherwise. The speakers being 4 ohms is good and speaker ground is not the same potential as "reference ground" such as chassis, body or BAT (neg). HU's and amplifiers use an "isolated floating ground" system. It does not correlate to car grounding systems.
Finally, as ttocs said... the gain control setting marks on the amp, are not always accurate. Use the technique he outlined until you get the best performance possible on this amp. If your amp keeps cutting out, you may wish to get a better amp.
Swez
pmpn8ez on 05/30/2004 23:06:18
Alright...the problem with the amp was that the gain was set too high and was clipping. The clipping signal reaching the speakers caused the amp to shut off. I bought a larger amp and set the gain to match my HU output voltage (5) and I can now grab a handful and make ears bleed without the amp cutting off. Thanks everyone for you're help,
swez on 05/31/2004 09:02:42
Good job PmP,
What amp did you buy?
Swez
pmpn8ez on 05/31/2004 12:20:06
I went with a Polk Audio C400.4 to push both sets of Kappa 60.5CS's...Sony sucks!!! Any ideas on a good mono amp that'll run good at 1 Ohm?...I've been looking at getting another set of 12's...the polk amp really kicked up the highs and there doesn't seem to be enough bass now ;)
One other question...any good sites that detail making custom boxes...using fiberglass? Thanks again for all your help.
-Lance
swez on 06/1/2004 11:29:39
Lance,
Nice choice on amps... Polk makes great speakers and I am sure their amps are also top notch. Have owned Polks for HT many years and never had a failure. Still using them 25 years later and they are very accurate.
As for box making in fiberglass, messy job here friend. Here's a primer on the subject: http://www.bcae1.com/fibrglas.htm
As for sub amps that are 1 ohm stable, there are a few out there in Class D versions. The other option is "HIGH CURRENT" (HC) amps which are often 2 channel. The "HC" amps are great for potent bass, but suck a lot of juice from the electricals. This HC style of amp is generally ~60% efficient. Class D amps are closer to 90% efficiency levels.
How much power do you think you'll need here for bass? Any thoughts on the subs you wish to use? I usually suggest about 8:1 ratio.... meaning, 800 watts for subs to every 100 watts for interior speakers. Yes, can go with a smaller ratio, but avoid less than 5:1 to keep your bass clean and distortion free.
Comments?
Swez
pmpn8ez on 06/2/2004 00:42:32
Swez/ALCON:
Whatta think of this amp?
http://www.kenwoodusa.com/product/product.jsp?productTypeId=11&sortBy=price&productId=2424
I can get it at the BX...A military store for under $300.00
swez on 06/2/2004 11:17:16
Not a bad amp here Lance. If you cut through all the specs jargon, looks like this amp will deliver ~800 RMS to a 2 ohm load, 1000 watts RMS @ 1 ohm. Not bad features and the price is very good as well. I would assume this amp is set up for #4 gage power wire and is fused by 3x25A or so. (not stated in web page specs though.)
OK, what subs to use? A pair of DVC (4+4) in full parallel will net a 1 ohm load for this amp. You may need to use #2 power wire here to supply enough current to both amps.
Swez
PS Amp specs and install manual:
ftp://docs.kenwoodusa.com/manuals/OM-KAC-X810D-2002-KUSA.pdf
pmpn8ez on 06/2/2004 18:09:26
Swez...hanks for the docs.
I already have two Infinity Kappa 120.1se and was just thinking of adding 2 more to drop it down to 1 Ohm...300W RMS each so 1200 for all 4...think the 1000W would be able to do the trick...could I run the Sony amp into the kenwood to boost? not to sure how the RCA out of one amp and into another works.?
Thanks,
-Lance
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