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Need Help From The Resident Experts

My problem:

My preamp puts out 30db of gain and the output impedance is 1.2K ohms.  My power amp input impedance is 22K ohms.  I can only use 1/4th of the volume controls (9 o'clock) and it is too loud after that point.  What would be the ideal output impedance for the preamp to mate well with the power amp?  Components in question are an Audible Illusions Modulus 3B and an Odyssey Stratos Extreme+++.  I would like to use more of the volume range and am open to a different pre.

stereo5
stereo5's avatar
stereo5 OP
6,571 posts
 
I appreciate all the responses, but the bottom line is I want a different preamp.  I am much older now and I would like remote control, phono input and either a tape monitor or processor loop.  I have been looking at the Rogue RP-5 and wonder if it will work well in my system.  What do you guys think?  Keep in mind I have had 3 Modulus preamps in my system since 1992 and I want to try something different.
almarg's avatar
almarg
9,670 posts
 
The RP-5's nominal output impedance of 500 ohms doesn't quite meet the guideline I suggested, and I couldn't find any measurements indicating how high that number may become over the audible frequency range.  So you might want to contact Rogue and ask them what its output impedance is at 20 Hz, and if they would recommend it for use with a power amp having an input impedance of 22K.

Otherwise I don't see any technical issues that would arise with the RP-5.  I have no particular knowledge of its sonics, though.

Hal, thanks very much for the nice words.

Regards,
-- Al
 
stereo5's avatar
stereo5 OP
6,571 posts
 

Thank you Almarg........

I plan on calling them tomorrow but I wanted to know what you guys think.

swampwalker's avatar
swampwalker
5,138 posts
 
What's your budget?
georgehifi's avatar
georgehifi
10,312 posts
 
My problem:
My preamp puts out 30db of gain and the output impedance is 1.2K ohms. My power amp input impedance is 22K ohms. I can only use 1/4th of the volume controls (9 o'clock) and it is too loud after that point. What would be the ideal output impedance for the preamp to mate well with the power amp? Components in question are an Audible Illusions Modulus 3B and an Odyssey Stratos Extreme+++. I would like to use more of the volume range and am open to a different pre.
stereo5
All to common, no need for a preamp with gain, try one of these for $49 and don't look back.
And you can sent it back, if you wish, I doubt you will.
http://schiit.com/products/sys

A Quote from the master Nelson Pass

Nelson Pass,
We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.
Think of it this way: 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.
Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.
What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.
And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp.
Cheers George
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