[P3GA]

Well, to escape the recent invasion from the in-laws, I decided it would be fun to go hide, dust off the shelves and try out some different preamp-amp combinations.

All was good until I decided to use the Nuforce Icon's line out on the back of the unit and feed the Teac A-L700P power amp, just to hear if there's any sonic difference in the amplifiers.

All was hooked and well until I powered the Teac on. Then a high pitched squeal emitted from the left speaker (the mini to RCA adapter cable is now suspect); the Teac shut down and went into standby. After unplugging overnight I tried powering it up - still in standby. Opened her up, there's no fuse anywhere to be seen, let alone replaced.

Don't know if I've cooked her or not. Question now is do I pay to have the amp serviced, or if cheap, cheerful, digital amps have progressed in the 5 years since the Teac was sold and if I should put the $$ into a new amp?

Anyone else have anything like this happen with the Teac?

Any recommendations for a replacement?

I've since read that I should have used the headphone out on the front panel of the Icon to feed the amp. Weird.

[TRADERXFAN]

I know there is a problem with some of the class d amps getting grounds combined. Usually the warning is for outputs to subwoofers though, haven't heard that on the inputs.

(For a while they were selling boxes to use the speaker level to make conversion to RCA for that purpose. Not sure where that magic box went, there was a wiring diagram by ed of the horneshoppe up.  That is the only reason I know of a problem.)

Sorry this happened to your equipment. Might ask Vinnie at Red wine what your options might be, he modded those teacs for a while...

-Tony

[Pez]

This really sucks man. What kind of idiotic design lacks a fuse? That is grounds for a lawsuit if that thing started a fire.

[mcgsxr]

I assume the unit is stock?

There are 2x2 channel amps in there, even thought the unit is only 3 channel.

I would try swapping the amp boards, to see if that is what toasted.

[Wayne1]

Opened her up, there's no fuse anywhere to be seen, let alone replaced.

This really sucks man. What kind of idiotic design lacks a fuse? That is grounds for a lawsuit if that thing started a fire.

I suggest both of you might care to gather more facts before you make such statements.

The TEAC is a very inexpensive amplifier that uses a switching power supply. There IS a fuse on the power supply board, near where the AC cable plugs in. It is not readily accessible as the unit does state there are no user serviceable parts inside.

Changing parts in this unit is not plug and play. If you have DIY skills, I suggest you contact TEAC to see if you can get the service manual. You may be able to swap the output boards, but getting the unit serviced by a professional may cost more than the TEAC sold for new.

There is a used TEAC that has been modded for sale in the Trading Post here on AC. That may be the way to go for you.

http://www.audiocircle.com/index.php?topic=75156.0

The Virtue amps are some of the better examples of Tripath based amps available today. You may want to look into them.

[mcgsxr]

PM me your email address, I have a pdf of the service manual, and other pdf's that might prove useful longer term, if you are looking to play around with the Teac.

[P3GA]

Thanks folks. Based on Wayne's comments about the fuse, I'll dive into the unit again. I'm guessing that the fuse is on the underside of the main board, visible only if said board is pulled from the chassis. It's lousy weather here in Atlanta, too cold to ride, too lazy to take down the decorations. Sounds like a perfect time to get crackin', wish me luck...and if this fails, the Virtue is looking like a very nice alternative (I think the modded unit lasted 8 seconds on Audiogon before being sold).

Have a very happy & safe New Year!

[Wayne1]

The fuse is on the power supply board.

Trace where the AC wire comes into the unit. Trace where it plugs into the power supply board. This is the board on the right side when looking at the unit from the back. You will have to remove screws from the board to access it.

With all that said, I do not think you will find a blown fuse. I think you blew up the output chip. The protection circuitry is refusing to allow the amp to power on any more until the fault is removed.

You might be able to remove one of the  output boards and swap in the other. This does require some DIY skills. Be careful. Don't touch any capacitors. They could still hold a charge.

[P3GA]

Many thanks to Mark & Wayne!

I was able to install the [previously removed] center board in place of the one I fried and the amp is back in operation.

Frankly I'm surprised that the board Teac designated for duty on the center speaker is identical to the L+R board. I would have thought that to save $$, the center would have been a neutered version.

Still the best $90 amp I ever purchased. It would have been a shame to relegate it to the junkpile.

I'm sure that development of the Tripath / Class D architecture (as well as others) have progressed in the 5-6 years since this amp was sold. Had replacement been in order, what amps under $500 would be candidates? The Virtue? Chinese Tubes? Ok, how about $750?
I really appreciate the speed, openness, and silent background of the chip amps.