I know this does not answer your question but, if additonal cost is not an issue, you should consider an M-60 monoblock pair (w/Speltz Zeroformers if loudspeaker impedance presents a difficult load). This, of course, assumes your loudspeakers are not power-hungry (most SET-compatible ones aren't).
I run balanced output from an Audio Note DAC into an MP-3 preamp into M-60s. My loudspeakers are connected only via Zeroformers. This system presents me, for the first time, an absolutely quiet background. The sound is thoroughly enjoyable (rock and acoustic/electric jazz). With proper listener/loudspeaker position the center images are holographic. I'm a permanent member of the "fully balanced" club.
I bought both the MP-3 and M-60s used on 'Gon, then had them fully tricked (recently added V-caps to both). This proved a very cost-effective (relative to high end gear prices) way to go. If you are concerned about Sino/Soviet 6AS7 output tube quality or availablity, I can attest to the very high quality and ruggedness of both the Chinese and old Soviet military versions. I've paid an average of under $10/tube for my stock of about 200 (roughly half Sino, half Soviet).
I can understand if you truly enjoy the sound of your SET amp, as I've owned a few myself. It's just that the, "Transformer maybe?", remark in your post caught my attention in the context of Atma-Sphere gear, albeit preamp only.
Best wishes in your search for the sound you want.
jb
I run balanced output from an Audio Note DAC into an MP-3 preamp into M-60s. My loudspeakers are connected only via Zeroformers. This system presents me, for the first time, an absolutely quiet background. The sound is thoroughly enjoyable (rock and acoustic/electric jazz). With proper listener/loudspeaker position the center images are holographic. I'm a permanent member of the "fully balanced" club.
I bought both the MP-3 and M-60s used on 'Gon, then had them fully tricked (recently added V-caps to both). This proved a very cost-effective (relative to high end gear prices) way to go. If you are concerned about Sino/Soviet 6AS7 output tube quality or availablity, I can attest to the very high quality and ruggedness of both the Chinese and old Soviet military versions. I've paid an average of under $10/tube for my stock of about 200 (roughly half Sino, half Soviet).
I can understand if you truly enjoy the sound of your SET amp, as I've owned a few myself. It's just that the, "Transformer maybe?", remark in your post caught my attention in the context of Atma-Sphere gear, albeit preamp only.
Best wishes in your search for the sound you want.
jb