Question About Audio Research Preamp Specs

Not that it matters over 1:10 I and many say.
But if you want high ratio go Krell preamp at 1ohm and Rogue Audio poweramp 1meg ohm!!!!! that’s an output to input ratio of 1:1000000 !!!

Cheers George

My Mac MC40 monoblocks have an input impedance of 250K ohm. Pairing it with a Audio Research LS15 and it sounds fantastic.
BillWojo

Hi All,

For those that might care, I followed up with Conrad Johnson regarding adjusting the output capacitors in my 17LS2 preamp. 

The technical person I spoke to understood immediately what I was requesting. Unfortunately, they explained that there is no room under the hood to replace the existing capacitors with larger ones.

The person did comment that their latest redesigns addressed this and the output impedance has been reduced.

I took a look myself and it would seem to my unpracticed eye that there is no space. The inside is chock full of large white "CJ" capacitors already!

In the meantime, I will explore different 6922 tubes that might help to mask the LF roll-off. Not sure if that makes any sense...

Otherwise, it seems like I may want to replace the 17LS2.

Thanks for listening,

Dsper

dsper OP
Unfortunately, they explained that there is no room under the hood to replace the existing capacitors with larger ones.

This Dsper is BS sorry to say, they either don’t want to do it or have other things in mind, go to a tech that will do it.

At least they know that the caps are too small as i first said to you.

The person did comment that their latest redesigns addressed this and the output impedance has been reduced.

Sure they can’t be put "maybe where the existing ones are, but there are other places they can go.
(PS: you can even add (parallel) more of the same type to make what’s there larger no need to get rid of the existing ones)

Here in this shot circled in green is the output rca’s of your preamp. Circled in red right next to them is 2 massive amount of spaces that you can put more new caps than you need, take it to someone who knows. https://ibb.co/r4LBDcc

Price should be around $40 for two good quality caps, and about a hour labour from what I see. This is a great preamp just needs those larger caps so it can show it’s greatness to you with your amp.


Cheers George

@dsper 

In the meantime, I will explore different 6922 tubes that might help to mask the LF roll-off. Not sure if that makes any sense...

It doesn't. Changing the tube won't affect the frequency response.