The tube preamplifiers and power amps available from Tubes4hifi and VTA, and their various iterations by Tube Nirvana, are nonpareil at even the most basic entry level. The spectrum is North American-built and incorporates the best of components, some of them foreign. (Who knew the Polish made the finest attenuators?)
I have piddled around with this stuff for several years, starting with building Bob Latino's M-125 and Roy Mottram's SP-14 kits, and now have Holger Schaarschmidt's (Tube Nirvana) M-125 mods for the power amps, and his top-end phono preamplifier, the Janis, which is a sweetly souped-up PH-16.
But when Mottram alerted me to Don Sachs' re-do of the SP-14, the antennae went up. Skipping a couple of mortgage payments, I purchased a Don's Sachs Model 1. It arrived the other day.
There are incremental improvements to be found in our audio toy collections. But the Sachs Model 1 is a step-level improvement. Bells ring. Brushers whisper. Bass tautly deepens. You hear a ding instead of a tink. And you learn the viola player might be a bit drunk when he farts.
Sach's preamplifier is almost too good. If you've got a bum tube or a bad mix, it will tell you straightaway. But if you've got a good input and your tubes are squared away, it will take full advantage of it. At present I am using Sylvania chrome-domes out front, RCAs in the back.
I am not a hi-fi reviewer and can't use all those esoteric verbs and adjectives. All I can truly tell you is that the Sachs SP-14 will fill your room with sound the likes of which you've never heard before. All that's left is that you need to develop a food budget for the musicians who have just invaded your living room. Thanks, Don. Fine work.