2. amps-preamps
  3. 143859-2497

Why do some fine solid state amplifiers like Soulution have such low input impedance?

I was looking at an excellent deal on a 5 series Soulution stereo amplifier to mate with my VAC Renaissance 5 preamplifier.  I then found out that the Soulution has an input impedance of 2000 Ohms balanced. Although my VAC is transformer coupled at the output, I am going to pass on the Soulution. Each component is too good alone to worry about a compromised “marriage”.  Do SS amplifier manufacturers find sonic benefit in such low input impedances, or is it really to discourage use with tube preamplifiers and encourage sales of their own preamplifiers?   
audiobrian
erik_squires
16,443 posts
 
Well, most SS preamps can drive 600 ohms without issue. The lower the impedance, the lower the EMF/RFI noise that can be picked up.

There may be other benefits, for instance, removing a gain stage, or minimizing it in terms of noise produced by the amp. It's been a very long time since I did this math.
Best,
E
erik_squires
16,443 posts
 
I should add, you probably should listen to the combination.

The worst that happens is a loss of highs at the extremes of the volume knob.


You may not care, or even like it. :)

Best,


E
roxy54's avatar
roxy54
8,108 posts
 
Almarg, your assistance is needed...
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