07-11-12: River251
Thanks Almarg. What sort of frequency response irregularities?
If I may be allowed to chime in - like Almarg wrote "Many tube preamps use a coupling capacitor at their outputs, which can cause their output impedance to be much higher at deep bass frequencies than at higher frequencies". So, the preamp output impedance is usually not a constant. It's often lower in the mid/hi freq & higher at bass freq. When higher in the bass freq, you *might* see a loss of signal power from pre to power + the loss of control by the power amp of the bass region. The listener usually perceives this as flabby/bloated bass.
I know that a friend of mine experienced this with a highly regarded preamp that had 600 Ohms output impedance while his power amp had 10K input impedance. It was a bad match & the preamp was sold off immediately.
I have a CJ PV-5 (only thing I found was a post saying 200 ohms output impedence) and Marantz 8B (and Mac MC240 and MC30s but listening to the 8B). I am considering trying a SS amp and considering B&K ST-140 (24Kohm input impedence), Aragon 2004 MkII (22Kohm), and McCormack DNA .5 or 1 (100Kohm).
from my personal experience this should not be an issue. My preamp has 200 Ohms output impedance & my power amp has 10K input impedance. The 2 units mate up very nicely across the entire audio freq range.
FWIW.
