Trying to add pre out/main in to integrated amplifier. Am I thinking right?

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Hi!

I was thinking about adding main in/pre out jumpers to an old Denon integrated amp. I haven't done this before but I think I might be on the right track. I have looked at its schematic and have made notes where I think I should cut the signal. I've enclosed the schematic here and have made green lines below R57 and R58. Am I thinking right?

Schematic (gif image)

If this will indeed work, will I need to do something else as well? I've read other threads on the subject and it seems further modification might be involved as well. Any insight would be very appreciated.

Thanks for your time. :)
 
The volume pot is part of the loudness circuit, you cant use
its input/output as separating point.

This should be inserted before R54 .
Just cut the circuit at this place, with R54 being the main input.

Thank you for your help, guys. :)

I tried this, and unfortunately, all it did was bypassing the tone control. The amp worked as normal, except that the tone control did nothing. Putting in the jumper re-enabled it.

This amp only has two knobs. One called "tone enhancer", which was what I now disabled. It basically works by removing detail, and adding some bass. I don't really understand its purpose, I never use it. And finally the volume control.

EDIT: By the way, the "tone enhancer" is VR1 on the schematic.
 
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Here:

PRE-OUT MAIN IN.JPG

It's probably safest to go ahead and add the caps.
If you notice a loss of lower frequencies, you can parallel additional 1uF caps to compensate.

Mike
 
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Fantastic. Thanks a lot for all your help and effort. Made my day. :)

Just one thought though, it looks like I will lose the volume control by doing this. I mean, if I connect the pre section to a different power amp.

Because the idea of this modification is that I would like to use it as a pre-amp.
 
Wow. You're my hero. :) I'm sitting here, using it as a power-amp... and it works marvelously. This is so much fun!

And an encouraging bit is that I actually looked at that section earlier and thought, couldn't that be where to add the jumpers?

Thanks a million. I've been wanting to do this for ages.
 
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