Soulution amp and tubed preamp

You didn't mention the specific ARC preamp model, but my strong suspicion is that it would NOT be a favorable match. Typically the output impedance of the ARC preamps having 600 ohm specifications rises to significantly higher values than that at deep bass frequencies. See John Atkinson's measurements of the Ref5 SE for example. In combination with a 4.7K load that rise will result in at least a slight rolloff of the bottom octave.

Also, ARC recommends a minimum load of 20K for many and perhaps most or all of their preamps having 600 ohm output impedance specs.

You are considering an amp whose design is based on a no compromise approach. I would not introduce a known compromise, however small, into its application.

Regards,
-- Al

Makes a lot of sense to me. Thank you Al. BTW, its the Ref10.

Psag,
Al gave you very good information. Here's an exception to the rule. Australian member Pap said he used a Coincident Statement Linestage quite successfully with a Soulution amplifier. The Coincident has an output impedance of 500 ohms. So an unexpected outcome given the numbers. Al's point is certainly the general rule of thumb is these situations. I have no idea why the Coincident is an odd exception.
Charles,