Follow-Up, July 1988
JGH wrote again about the Threshold SA-1 in July 1988 (Vol.11 No.7):
The original version of this has been my reference amplifier since I reviewed a pair of them two years ago (Vol.9 No.1), and although it has since seen a number of small but significant changes, I felt I couldn't part with mine for long enough to get them upgraded. Finally, when I saw that I was going to be out of town for a week, I sent them back.
What I got in return was, for all intents and purposes, a pair of different amplifiers. On first listen, right out of the box, they sounded quite badharsh, rough, and thin. But so do most other amplifiers right out of the box. I let them warm up for 48 hours and took another listen. The roughness was completely gone, replaced by a much smoother, sweeter high end than my original units. But there were other, less expected differences. The new SA-1s were somewhat tighter but sparser through the low endalmost too much so for my Sound Lab A-3 speakers at their Flat LF setting. They were also more bright and a little more forward than before (by brightness I do not refer to extreme high end, but to middle highs). That change, too, was something that did not sit well with the A-3s. Low-level detailing was much greater than before, butagain in the context of the A-3ssounded like an exaggeration of detail, in that I was hearing from most recordings more such detail than I cared to. Like the rustle of clothing, and assorted sniffs, snuffles, and grunts from the performers.
This is still definitely a Class A power amp, even more so than it was before. But as of now, I cannot recommend it for use with speakers having the A-3's spectral balance. It is better suited to speakers that are a little warm through the bass and a bit withdrawn through the mid treble. This may not be the last word on the SA-1, though, if my experience with the first pair is to be repeated with these. Over a period of months, that first pair gradually grew warmer and richer-sounding, like a fine violin that blooms with playing. The latest pair may do likewise.
Stay tuned.J. Gordon Holt