Gain Matching - need advice


I recently added an Audio Research Ref 6 to my system (it was a dealer demo unit so price was right).  The preamp is paired with Pass Labs XA 60.8 amps (26db gain and 100K ohm input impedance) and Avantgarde speakers (sensitivity of 108 db at nominal 8 ohms).  The problem I am having, that I did not have with my previous Joule Electra LA150, is volume control.  The AR preamp has a 103 position volume control.  At position #7 the volume is almost ear splitting.  Sure I can turn it down but it’s very difficult to dial in a suitable volume.  I am inclined to blame it on the new AR preamp (output impedance of 600 ohms and 12db of gain).  I am stuck into using balanced interconnects which I won’t go into.  My first conclusion was that I have a gain matching problem since the old preamp did not behave this way.  Looking at the difference between the output impedance of the preamp and input impedance of the preamp ... why would there be a gain matching problem (at least as I understand the subject ... which I may not.  Anything that can be done about this, or a new preamp the only solution?
chilli42

Showing 1 response by audioman58

By using xlr interconnects your db output is 2 x as much ,the volume pot on the Joule also seems to be much less , 
with speakers this efficient  did the dealer give you a 30day audition  for comparability ?  You should  try a pr of rca interconnects , just to see how much gain and if thisis then suitable , if not the preamp  is not a good match and needs to go 
back ,or sell it ,  Don Sachs would build your custom preamp 
to have ample gain , for I doubt the AR volume control is a shunt, resistive ladder type, Aron Sachs uses a A Khozmo which I have used several times , if you want a true top of the Line RaduTarta
builds DHT custom preamps using all top transformers and 
can build to your amplifiers output for $5k you can have a preamp 
with far superior parts quality.I know for not only do I know about 
modding or upgrades for years ,but he is a 40 year expert in vacuum tube equipment SET amplifiers , and DHT preamps are by far the purest but. Incredible build quality and musicality ,even the exterior can be custom wood or metal and he uses several excellent brand  volume attenuators , which can make or break 
your preamp , for your speakers you have Waay too much gain 
in all honesty you-should have agreat 8 watt set amp , your speakers use only 3-4 watts ,the gain is high ,any speaker with over 100 db efficiency  , made for a high quality low power amp .
SSamps typically have too much gain send Nelson Pass a Email
See what he would do , his great 20 watt amps for around $4k
woould be ideal ,not 60wpc . Send Nelson an email he will help you  things out . If you want a great vacuum tube preamp,or SET
tube amp Radu Tarta without  any hesitation ,and per $dollar spent 
by far the best parts quality ,for he builds each one by hand 
and no dealer markup . You discuss what your budget max is 
and then take it from there , do a search ,build quality for a life time at very fair prices.