Sound-Lab A-3 loudspeaker J. Gordon Holt, November 1988
I am combining two followups into one here because both products were involved in one of the worst mistakes I have made in many years of testing: I had two of my reference components upgraded at once.
At a recent show, I had heard the latest version of the Threshold SA-1 driving MartinLogan Statements, and observed that the high end was noticeably improved in quality—sweeter and less dry. I arranged to return mine for updating.
While they were gone, and my reference system would be out of commission for a week or so, I figured that would be an ideal time to install the new power-supply modules Sound-Lab had sent me some weeks previously. After I completed the job, I had no amplifiers on hand whose sound I was familiar enough with to assess the sound of the speakers. All I could tell was that, as claimed, the speakers' sensitivity was now about twice what it used to be (see Vol.11 No.6). A major plus!
When the SA-1s returned from Threshold, I gave them a 24-hour warmup and then auditioned them with the A-3s. The result was not pleasant: a relentless steeliness that no amount of adjustment of anything seemed able to control. Where was this spurious brightness coming from? The upgraded amplifiers or the upgraded speakers? Or both, maybe?
A brief listen to the A-3s with a pair of VTL 300W monoblock power amps seemed to exonerate the speakers. But before I had a chance to check out the SA-1 amplifiers under more controlled conditions, our semi-annual "Recommended Components" had to go to press (see the October issue), so we had no choice but to pull the Thresholds out of Class A and put them into Class K (Products to Watch) until the matter could be resolved.
Subsequent listening with the Thresholds has now qualified them for reinstatement in Class A, but my previous followup caveat—that the SA-1s and A-3s can no longer be recommended for use with one another—was confirmed. The latest SA-1 amplifiers are slightly brighter and more forward than the previous version, which is not in itself a disqualification for a supremely good amplifier. (The Mark Levinson No.23 has much the same brightness.) But the same thing also seems to be the case with the upgraded, higher-sensitivity SA-3 speakers. Again, this does not disqualify them as long as they aren't used in an acoustically bright listening room. But just put these two components together, and watch your ears bleed!
As of now, the A-3s remain my reference speakers for several reasons, not the least of which is that I still love the way they sound—but not with the SA-1s. They do better now with the VTL 300s, although I am still fighting the good fight to try and regain some of the seductive richness that first made me fall in love with the Sound-Labs. (And that was using them with the early SA-1s.) The Thresholds will stay around too, as a second reference amplifier, but only for use with speakers that are a bit reticent through the brightness region.—J. Gordon Holt