TFM-15cb low sound

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Yellowneck
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TFM-15cb low sound

Post by Yellowneck » Thu May 07, 2009 3:38 pm

I did a search and could not find anything and did search through the forums manually but did not have time to check each one. I am just wondering if anyone else has had this issues or may know what might be causing it.

I am currently running individual TFM-15cb's for my speakers. This is a 7.2 setup. I have seven TFM-15cb's all together. All have same issue. Each amp is bridged and speakers are all Polk Audio RTi's at the moment. The problem I am having is very frequently the amp will put out lower than normal volume of sound and the right meter will either not work or will not move in sync with the left meter. All the amps do not do this at the same time but all of them have this condition. I have opened up each amp and tried my best to give it a good visual and do not see any bad solder's, loose connections, burn marks, etc... I have already tried using different interconnects, and speaker cables and still have the same problem. I also tried a different pre/pro and this did solve the issue.

When I turn off the amp that is not functioning correctly at the time I can remove the RCA interconnect and put it back in then turn on the amp and it will work for a while but then problem will come back. Sometimes it comes back same night other times it works for a couple days and then starts to have same issues. All of the amps are doing this. Amps are all in a open Audio rack with only one stacked on top of another with 1" spacers in between. So far there have been no heating issues, amps get slightly warm and that is about it. I have tried playing with the gain knobs and nothing, unplug and plug in speaker cables nothing, unplug and plug in RCA's everything works like it is supposed to for a while then back to same issue.

I love the amps but do not really want to send them out to get fixed as I can probably get new/newer amps for about the same cost as it would to have them repaired if there is an issue with the amps.

Any hep would be appreciated.

Thanks

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thuffman03
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Re: TFM-15cb low sound

Post by thuffman03 » Thu May 07, 2009 3:53 pm

What a problem you have.

To have 7 amps all having the same issue not at the same time sounds like a pre/pro issue and not an amp issue to me.
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treitz3
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Re: TFM-15cb low sound

Post by treitz3 » Thu May 07, 2009 4:16 pm

Yellowneck wrote: I also tried a different pre/pro and this did solve the issue.
Hello, I'm in no way trying to a smart ass here but if you replaced the pre/pro and it solved the issue why don't you keep the working pre/pro in the loop?
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Re: TFM-15cb low sound

Post by frankieD » Thu May 07, 2009 5:10 pm

treitz3 wrote:
Yellowneck wrote: I also tried a different pre/pro and this did solve the issue.
Hello, I'm in no way trying to a smart ass here but if you replaced the pre/pro and it solved the issue why don't you keep the working pre/pro in the loop?

Tom is right! If replacing the pre solved the issue than the pre IS the issue.

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Re: TFM-15cb low sound

Post by BillD » Thu May 07, 2009 7:09 pm

But I'm sitting here scratching my head saying why would disconnecting and reconnecting the ICs make the problem go away for awhile? It occurred to me that the caps in the preamp or amp might not be storing juice anymore.
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Yellowneck
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Re: TFM-15cb low sound

Post by Yellowneck » Thu May 07, 2009 8:02 pm

Sorry about that it did not solve the issue. I am still having same problem as before. I was at work and in a hurry.

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Re: TFM-15cb low sound

Post by Jag_97470 » Thu May 07, 2009 8:09 pm

Ummm, copy and paste from post; Each amp is bridged and speakers are all Polk Audio RTi's at the moment. Could it be bridging the 15CB's clipping the speakers? Maybe try all amps only running off one channel "not bridged" and see what happens.

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Re: TFM-15cb low sound

Post by beemers417 » Thu May 07, 2009 8:30 pm

You need to post a pic of that stack. =D>
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Yellowneck
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Re: TFM-15cb low sound

Post by Yellowneck » Thu May 07, 2009 10:36 pm

Volume doesn't matter it can be low moderate or movie level and it will happen.

I still do not have a digital camera so I am unable to take a picture. I will be getting one here within a month or so. I am just not the picture taking type. Looks kinda cool though, seeing all the meters move.

I will also try and take a picture of a friends system when I get the camera. He has same setup as me but with M1.0Ts playing Definitive Bi polar towers that have built in subs. He also has a Sunfire mkII sub in his setup. Never heard anything with such sonic depth until I heard his setup. Front towers have 15" subs, Center has a 10" sub, Surrounds have 8" sub. Doesn't matter the volume it will literally take your breath away.

So far I have taken the amps off of being bridged. Went out and bought a whole bunch of speaker wire, Monster XPHP, a couple hundred feet. Speakers are still using their own amp but the amps are set up so that the left channel drives the highs and the right channel drives the lows. So far it has been playing all night without any issues. I am thinking that the ohm load from my speakers were too low for the amp. I checked each set of post high and low seperately. Highs had a resistance of 7.8 ohms and the lows were 6.5 ohms. This would show roughly a 3.5 ohm load to the amp and I think in bridged it was just too low of a load.


Anyone else ever had this issue with any of the carver amps?

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Re: TFM-15cb low sound

Post by TNRabbit » Fri May 08, 2009 2:11 am

Well, I do know VERY few of the Carver amps (pro models?) are rated to drive below 8 ohms in bridged mode, and I don't think any of them are rated for 4 ohms in bridged, so that could be your problem....
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