Doug uses Audion 300B amps. at the factory, but they are six times the cost of the Marantz.
He told me the ‘6004 is very good value with a neutral sound.
To ( sort of ) revive this thread, I was recently in touch with Doug Stirling re. amplifiers.
He recommended the Marantz PM6004 to use with the V3s.
Fortunately one became available via PFM, so I took a chance.
The Quad 34/303 was good.
The Arcam Delta 60 was excellent.
The PM6004 is superb !
More detail, a bigger soundstage and slightly better definition in the bass.
The extra detail doesn’t come with extra brightness, which can sometimes be the case.
I haven’t yet tried the Marantz with my Spendor BC1s.
I’ve got that to look forward to...