integrated no no


Is this wrong:

I hooked up my exposure 2010s with its pre outs into my Luxman l58a "main in" and ran it as a power amp. So essentially I bypass the exposure amp and use its passive line-stage into the Luxmans main amp by switching off its preamp.

What I tried after that and worked was running the Luxmans phono stage through the tape outs into the exposure and then back into itself. I didn't think it would work because I wasn't sure exactly what functionality I would have after bypassing the preamp. The result was better than I expected maybe due to the lack of any additional gain running through the phono stage. The noise floor dropped significantly and the imaging became better focused and detailed.

I had done this before but not with the phono stage running back into the integrated. Makes me want to run passive into a pure class A design.

My question is will this put the integrated in jeopardy? Could it cause a short or something of that nature.

Thanks and sorry for being long winded.
enobenetto

Showing 1 response by almarg

I looked at the descriptions and specs of the two units, and I don't see any problem doing that.

As always, you would want to turn the amplifier that is driving the speakers (the Luxman) on last and off first, so that it can't amplify turn-on or turn-off transients that may be generated earlier in the signal path.

Impedance compatibility looks ok, in terms of sonics. (An impedance incompatibility would not cause damage, in any event).

If the Exposure's amplifier section had a tube output stage and output transformers, you would not want to operate it without a speaker or equivalent resistive load connected, but it is solid state so that is no problem.

A point to be aware of, though: Although the signal path through the preamp section of the Exposure to its own amplifier section is passive, its pre-outs are driven by an integrated circuit chip, probably an "op amp" (operational amplifier), which provides a low output impedance and approximately 18 db of gain. So you are not truly using a passive preamp in the configuration you describe.

Regards,
-- Al