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[Gordon Gray]

Hi Gordon,

Maybe a dumb question but how do you overdrive a preamp?

What do you hear when it is overdriven?

GG

 

[SundayNiagara]

Hi Gordon,

Maybe a dumb question but how do you overdrive a preamp?

What do you hear when it is overdriven?

GG

I agree on the long balanced interconnects, but would also like to know the meaning of "overdrive."

 

[tonepub]

Some older preamplifiers had slightly higher gain and only need a volt or less to achieve maximum output. Typically, your preamp is attenuating gain.

So with todays sources often having 4v outputs (many CD players) if your preamp doesn't have enough headroom, you can get some distortion in your preamp. It sounds like you plugged a MM cart into a MC input. Not always this bad, but on very dynamic material, you can hear some compression or a little distortion creeping in.

 

[Gordon]

I'll try to explain this "overdrive" condition. The pre amp is a two piece unit. One is the controller and the other is the actual pre amp. All audio goes through the pre amp only. The controller only selects source, volume and balance. I imagine it does more than that, but that is limit of my electrical knowledge!

Once a source is selected and I hit play, the pre amp runs out of gain and the meters are pegged at +3 db while only achieving 5 watts output at the amplifiers. A very slight distortion occurs with a complete collapse of the stage. I understand that the meters are only about 95% accurate but I am showing about a 20-25 db split between the pre and amps which should track much closer than that.

So the controller is probably at fault for this overdrive or loss of gain in the pre. I'm really stretching my knowledge on this kind of stuff but the techs at McIntosh believe it to be so.

I hope this attempt to explain makes some sense.

Gordon

 

[Gordon]

Well, I finally have this issue resolved. I bought the original pre amp from Audio Classics. The customer service from these guys is above reproach. They ended up sending me three different combinations until I got a set that worked to spec. I know they spent at least $700 in shipping to get me working correctly and to my satisfaction.

I would not hesitate to buy anything from these guys again even considering the problems I had.

Gordon

 

[JonFo]

Well, I finally have this issue resolved. I bought the original pre amp from Audio Classics. The customer service from these guys is above reproach. They ended up sending me three different combinations until I got a set that worked to spec. I know they spent at least $700 in shipping to get me working correctly and to my satisfaction.

I would not hesitate to buy anything from these guys again even considering the problems I had.

Gordon

Hi Gordon, I'm glad it all worked out and that you're happy with the result.

It's a shame that high-priced audio gear seems so fragile. I'd expect for the kind of money these things cost that they'd be practically bulletproof.

 

[Gordon]

Hi Gordon, I'm glad it all worked out and that you're happy with the result.

It's a shame that high-priced audio gear seems so fragile. I'd expect for the kind of money these things cost that they'd be practically bulletproof.

Jonathan, one would think so, but it seems to me the more it costs the more fragile it becomes. I work with electronics and some of the shipping containers cost more than than the pre amp I bought. Many of the pieces I work with cost in excess of 700K and they fail new from the manufacturer due to bench calibrations being off.

I did not get spooled up too tightly based on my experiences with uber-expensive electronics. I'm just happy the crew at AC were a bunch of pro's and satified me!

Gordon