Slight Buzz through Amazings

[Don]

Hi guys,

Trying to trouble shoot slight buzz through Amazings. Does not get louder with volume increase. Eliminated equalizer from equation, tried different interconnects between pre/amp receiver and TFM-75, plugged into different wall outlets, still there. Have a hum bar on DVD's. Sounds like it may be a ground loop. Disappears when I use the amp in the receiver connected to Amazings and disconnect the TFM-75 and turn off.

My question is this: Can I hook the TFM-75 directly to the Amazings with the volume potts all the way down and see if I still have the buzz to determine if there is a problem with the TFM-75 while bypassing the receiver and not damage anything? I figure by isolating this way, it will tell me if there is a problem developing with the TFM-75 or a ground loop issue?

Thanks,

Don

[gdb]

Don, not too long ago someone had a hum/buzz they couldn't figure out, it turned out to be a fan that was the culprit. Does the 75's fan run continuously ? Might be something to check/disable temporarily.

[Don]

Thanks. I really don't know if it runs all the time or not. My listening area is a good distance away and with the volume I play the Amazings? I can check that out.

By isolating the TFM-75 direct through the Amazings, if possible without damage, that may also lead me in the right direction. I will wait for someone to weigh in on that before pursuing.

[gdb]

IF I had an amp that rare and valuable.....I wouldn't think twice about sending it to Bob & Rita's shop for a complete "physical" !!

[Don]

That may be on the drawing board. First I need to see who or what is the problem before sending in the amp. I don't want to risk cosmetic damage to an amp that still looks like I did when I bought it new. It may not be the culprit. It may be just a ground loop.

[treitz3]

Yes Don, that will be fine. Just make sure [as you probably already know] to power everything off before connecting anything.

Then hook your source directly up to the 75 [again, powering off and the 75's knobs all of the way down] without having anything play in your source. Slowly turn the knobs up and see if the issue is present.

Which ALS do you have?

If the fans are an issue or they are in question, just disconnect them and test for the issue, obviously without playing the system loud for extended periods.

[Don]

Thanks for the reply. I have Plat. 4's. Will try it out this weekend with nothing connected to it but the Plat's. Currently moved my Legacy Focus speakers up to the media room to use with the Marantz receiver in the meantime. Back a little sore right know moving Focus from 1st floor to 2nd. Marantz is way underpowered for the Plat's. TFM-75 shut down until I have a chance to troubleshoot as discussed earlier in my post.

[F1nut]

Is it a slight buzz or is it a 60 cycle hum?

[Don]

It is a very slight buzz rather than a hum. Although it does show up with the TFM powered up through the Panamax (everything is routed through there) as a rolling single bar on the TV when I play DVD's. However, when the TFM is out of the loop, no bar when I use the Marantz front channel amp of the receiver.

[F1nut]

In that case, it's not a ground loop problem. Time for your amp to take a trip to the repair shop.

[gdb]

Did it occur to you that the Panamax may be the problem itself? I don't know but I suspect that it ain't up to the task of feeding the voracious power needs of a TFM-75, in fact, I beleive that they're spose'd to be connected to 2 separate circuits anyway. Try plugg'n that big boy directly into the wall an see what happens.

[F1nut]

Did it occur to you that the Panamax may be the problem itself?

Excellent point.

[Don]

Guys,

Finally traced my problem down. By disconnecting everything and plugging back in one at a time, it turned out to be a bad transformer for a security camera plugged into one of the Panamax's. GDB, I have three panamax's with which my home theatre equipment is connected to. The TFM-75 with it's two power cords are plugged into two of them. A bear to track down, but problem is now resolved. I have five separate dedicated circuits for my home theatre. I ended up buying a Panamax power strip and isolating all security camera transformers from other home theatre equipment on a separate circuit. This way I did not go through any of the circuits the Panamaxs' with the home theatre equipment was plugged into. Thanks for all of the replys!

[engtaz]

Congrats on the find. I know that had to piss you off.

[tfm75]

Glad you were able to track down the hum or buzz. The 75 is a beast and can with the wrong conditions buzz in the speakers. She needs a clean socket x2 from the amp to the breakers to sound the best.

At full power the TFM-75 is almost pulling 3000 watts out of the wall.