Question About Audio Research Preamp Specs
Maybe I should call CJ and ask them if they can adjust the caps on the 17LS2. Great idea, tell them you want the "uF" of coupling cap increased so you can have "little or no" rolloff above 20hz into your amps 10kohm input impedance. This is around $20 for the caps, and a 1hr labour. My calculation for 17ls2’s new coupling caps into the 10kohm of the amp. Any/All are fine. 4.7uf will be -3db at 3hz 6.8uf will be -3db at 2.3hz 10uf will be -3db at 1.6hz Cheers George |
Take that with a grain of salt. I do prefer direct coupling (no cap), best cap is no cap mentality.This is why we direct couple... this limitation is eliminated. In the photo of the Aesthetix its not clear what the actual value of the coupling capacitors is. But obviously the Aesthetix faces the same issue of what is the lowest impedance it can actually drive actually; this information does not show up in their specs or operating manual. |
georgehifi, "Great idea, tell them you want the "uF" of coupling cap increased so you can have "little or no" rolloff above 20hz into your amps 10kohm input impedance." georgehifi, You certainly have given me some discussion points with CJ and what is possible to accomplish. Thank you! Why would CJ not have done this in the first place? Maybe a cost/benefits decision considering how relatively few amps have 10K ohm impedance? Or could this possibly change/degrade the overall sound of the preamp? I assume my last question may illustrate how little I know about this technical stuff so any additional comments would be greatly appreciated! Thanks for listening, Dsper |
Atmosphere, " But obviously the Aesthetix faces the same issue of what is the lowest impedance it can actually drive actually; this information does not show up in their specs or operating manual." I do not understand technically why a particular preamp may have a greater capability to drive a low impedance amplifier. While, I try to follow these types of discussions, something basic is lacking in my current understanding as well as how it impacts how it sounds.. Could you perhaps elaborate further or direct me to another thread where I am sure that this has been covered before? Thanks for listening! Dsper |
Why would CJ not have done this in the first place? Maybe a cost/benefits decision considering how relatively few amps have 10K ohm impedance? It wasn't common to have such low 10k input impedance poweramps in the past, as the loosely based standard was 47k or 50k and many especially tube were 100k. Ever since Class-D has reared it's ugly head has 10kohm become more apparent, which means it's not suited to many tube preamps and also many passives. I believe there should be one standard and that's 100kohm then anything can drive it, hell Rogue Audio use 1megohm on their poweramps and they don't have any problems at all. Cheers George |
