2. amps-preamps
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Amp-preamp mismatch?? result higher volume. What is rthe cause??

Several months ago, I changed amps from a BAT VK200  to a P.S. Audio S-300 amp. I also invested in a new interconnect, the Audience "Ono"  which replaced  a basic Harmonic Technology " Truth Link" which is used  now between the preamp and the CD player  The P.S. Audio amp is very dynamic  but also more forward, but not aggressive 


Pre-amp is a Conrad Johnson PV-14SE and which I like very much 9uses two tubes in the output stage.  The current combo of interconnects has sounded louder (and more forward in the midrange) at the same volume setting used before with the BAT amp  To its credit, the P.S, Audio provides better detail and depth in the midrange than former BAT amp  


So, is there an impedance mismatch between the power amp and pre-amp??   Or  is the increase in volume a consequence of a mismatch between the interconnects, either to the amp or the connection between the amp and pre-amp??


Please advise.

Thank you

S.J.

sunnyjim
rodman99999
5,981 posts
 
The PS amp’s sensitivity is lower (1.01 vs 1.6V) for it’s (higher) rated output/gain, compared to the BAT.             +1 (each for testpilot, millercarbon and twoleftears)
three_easy_payments's avatar
three_easy_payments
2,097 posts
 
For amp designers volume knobs totally matter.   If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.
tubegroover
2,320 posts
 
LOL MC, That is too funny!
auxinput
2,920 posts
 
If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.
This is correct.  And there are actually some preamp that just don't give a good quality audio signal if the volume/gain is set so low.  They really work better and higher signal levels, so if your volume is not up in the 11 o'clock to 2 o'clock level, you may not be getting the most out of your preamp.


erik_squires
15,647 posts
 
While a lot of power amplifiers do use a conventional amount of gain (23 dB? 28? something like that) it’s not a

requirement. Preamps tend to vary a lot more in the internal total gain, and for sure, you can’t compare volume knob direction between them, as nothing is standardized.

I do wish preamps had a lot less gain though. I’d like to have more control between off and 12 o’clock.
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