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Impedance matching with tube amp

I have a Mccormack DNA 0.5 which has an input impedance of 100kohm. I'd like to get the Schiit Saga preamp, which has an output impedance of 180 ohms. Now, I've read about the 10:1-100:1 ratio of input:output impedance for power amps and preamps, so this wouldn't quite fit that range of ratios. Would this still be a good option, and if not, what other (<$500) tube preamp options do I have?

Thanks!
muffinhead123
kalali's avatar
kalali
1,645 posts
 
ARC Ref3 output impedance is 300 ohms SE and 600 balanced. Anyone designing a preamp with a 100K ohms output impedance is in the wrong business...
hansk46's avatar
hansk46
109 posts
 
hello Kalali ,
You are right  about the 600 Ohm , sorry fellow audiogonners  for the wrong figure I give . When I got the Sphinx poweramps I thought 600 Ohm to 600 Ohm  no problem , but ARC poweramps all have 100 k input imp to be sure about the lower registers .
bdp24's avatar
bdp24
4,908 posts
 
hansk46's figures may be incorrect---100k output for the ARC Ref3 certainly is, and 600 ohms for the input of the Sphinx is, if correct, by far the lowest I have ever seen in a power amp.
atmasphere's avatar
atmasphere
7,068 posts
 
Anyone designing a preamp with a 100K ohms output impedance is in the wrong business...
And none exist, except for passives.

and 600 ohms for the input of the Sphinx is, if correct, by far the lowest I have ever seen in a power amp.
We make a tube preamp that can drive 32 ohm headphones... 600 ohms is the old school defacto standard for balanced inputs. Our MA-2 amplifier input impedance is switchable (600ohms and 200Kohms, balanced), since the low impedance impedance (if the preamp can drive it) is helpful for eliminating any 'sound' from the interconnect cables.
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