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Preamp output voltage...affect on volume???

I am in the middle of auditioning a new preamp which outputs 50 vrms max. My current preamp outputs 20vrms max. Assuming they are both pretty close in terms of gain and have the same number of volume steps (100 @ 0.5db each), does that mean the preamp with the 50vrms output will cause my sysem to sound louder than the 20vrms preamp (all else constant)? If so, how much louder?

thank you...
tboooe
tboooe's avatar
tboooe OP
1,009 posts
 
Ok, I found out the gain of the classe is 14db, the bat is 17db. any ideas?
tboooe's avatar
tboooe OP
1,009 posts
 
I got a response from BAT that explains the difference in volume control between my Classe preamp and the VK-52se even though they both have similar gain. I guess it comes down to digital volume control (Classe) vs discrete volume control (BAT). By the way, what is a "Discrete" volume control? Can someone explain why discrete volume control does not have as much attenuation as digital control?

Below is an exerpt from the email I got BAT sent me:

"...integrated digital volume controls give
you more room - they have 180 or more steps, allowing you to achieve greater
attenuation. I don't have solid information on Classe, but what you are
telling me is consistent with a use of such a volume control.

High quality discrete volume controls usually stop sooner. Reasons are
practical - cost and complexity...It is many times more expensive
than the integrated circuit attenuator. The reason we use that expensive
solution is the sound, of course.

Our volume attenuator has linear range of 70dB. We do not go further as
doing so would degrade the signal way too much. -60dB attenuation means you
are throwing away 99.9% of signal, letting just 1/1000 of it go through -
hardly good situation."
herman
2,280 posts
 
The maximun gain is within 3dB, not enough to explain the difference.

The output impedance is essentially the same compared to the input impedance of the amp.

The input impedance of each compared to the output impedance of the CDP should make no difference.

That leaves us with the taper of the volume controls. The only logical explanation I can see is that the louder one's steps are bigger at lower volumes than the other one. Have you contacted the manufacturers to see what they have to say?

If you want to ship them both to me I can measure the gain at the different control settings. You could do this yourself with a test CD and a cheap multimeter if you really want to know.
tboooe's avatar
tboooe OP
1,009 posts
 
ok, i think i figured out what BAT meant when they replied to me. My Classe has a gain range of -84db to 14db. The BAT has a range of 70db, from -53db to 17db. So on the lower end, the Classe is attenuating by more than -30db which explains why on the lowest volume settings, music sounds so much louder. This doenst help but at least I understand what is going on.
herman
2,280 posts
 
Thanks for the follow up. It helps in the sense that when it comes to gain you now know what you are looking for in a preamp. If you want to stick with the rest of your components you either need one with a lot of attenuation like the Classe or you will need extra attenuators.
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