Modwright LS100 VS Modwright LS36.5

I have owned the LS-100 as well as other 6SN7 based preamplifiers, and while I have not owned or heard the 36.5, I have owned another 6H30 based preamplifier and I have to say that I prefer 6SN7 preamps to 6H30 preamps in a general sense.

The 6SN7 preamp will have more tone, warmth and body then the 6H30 preamp, while the 6H30 preamp will be remarkable in its clarity.

But a lot of this really depends on synergy with the rest of your system and your personal preferences. Also, if you're looking for a balanced preamp, the LS 36.5 is truly balanced versus the LS-100 which has XLR outputs only for convenience.

What does the rest of your system look like?

I'd go with the LS-100. The highly resolved, ever so slightly warm (for a solid state amp that is) and inner detail and micro-dynamic finesse of the Pass amplifier would be complemented well by the richer texture of the LS-100. Personally, I think a 6H30 preamp here would be a bit boring.

I know a lot of people aim for absolute neutrality, but you know, one person's neutral is someone else's cold fish. Fortunately, I think a Harbeth owner would appreciate that sentiment.

When I had the LS-100, it was outfitted with Sophia Electric 6SN7 tubes and Mullard 5AR4 rectifier.

I presently own the Atma-sphere MP-3, which I think is slightly more neutral but just as beautiful.

Best 6SN7 preamplifier I've heard is the TRL Dude. I owned one briefly, but its chassis was too large to be suitable in my shared listening room. That might not be a problem for you.

As for DACs, I think one of the best values out there right now is the NAD M51. I'm really impressed with it, and having been through many DACs over the years, I can say this one is a real standout. At least it is in the $1500 - $3000 range.

That's right, it's very difficult to tube roll the 36.5. There are only three choices for the 6H30. Two new production manufacturers which are sonically nearly indistinguishable, and the very expensive DR version which is NOS. The DR version is more of a good thing, but in terms of character, pretty much the same.