Carver Research Lightstar Reference power amplifier Page 2

I was ready for some serious listening. I went through the usual test pieces (Chesky, Reference Recordings, etc.), and also listened to some "ordinary" records that I just happened to feel like playing. The sound was impressively neutral, the amp doing little to call attention to itself—which is just what you want it to do. With the Lightstar in the system, I was content to listen to the music, and felt little urge to switch over to one of the other amps I had on hand (all of them more expensive). This, too, is a sign that an amplifier is doing something right.

Dynamics and a sense of power held in reserve were among the Lightstar's major strengths. The ebb and flow of large-scale music—such as the dramatic first movement of Nelhybel's Trittico, track 1 on the Reference Recordings HDCD sampler—played at a realistic level (ie, loud) had the sort of effortlessness that only muscle amps seem to be able to deliver. At the same time, the Lightstar didn't have that rough-around-the-edges quality that typically accompanies muscle amps. The critical upper midrange and treble were smooth and refreshingly free of hardness or edginess.

Timbral accuracy was excellent, voices and instrumental textures sounding quite lifelike. The opening of Turandot (London 414 274-2) was crisp without being overly etched. If everything isn't just so, this recording can easily start sounding harsh; the fact that it didn't is a tribute to the quality of the reproduction chain, including the Lightstar. If anything, the Lightstar's presentation was on the soft, forgiving side, with perhaps a bit of added warmth. (Did someone say "tube-like"?)

In my opinion, most non-audiophile recordings are balanced to be too bright and forward, so the Lightstar's slight tendency to counteract this wasn't such a bad thing. To put it in comparative terms, the Lightstar's tonal presentation reminded me of that of the Krell KSA-100S I reviewed in September 1994 (Vol.17 No.9), but with better dynamics. The Bryston 7B monoblocks were more dynamic still, but they had a touch of brashness when dealing with the orchestral/vocal complexities of Turandot.

The contrast between the Brystons and the Lightstar was also brought out by Beachcomber, a new CD of wind-band encore pieces by Frederick Fennell and the Dallas Wind Symphony (Reference RR-62CD). "Russian Sailor's Dance" had natural timbres, excellent dynamics, and very good depth and ambience through the Lightstar; switching to the Brystons resulted in a sharper, crisper sound that better communicated fine details and depth/ambience, but it sounded a bit more "electronic."

With this recording, the Threshold T-200 (see my review in April 1985) provided the best overall balance between dynamics, clarity, sweetness, and bass extension/tightness; but the Lightstar wasn't far behind. This was the case at loud-but-sensible levels. At very high levels (peaks measuring about 103dB, C-weighting, "fast" response on the Radio Shack sound-pressure–level meter), the Lightstar surpassed the Threshold T-200 in the ability to drive the Dunlavy SC-IVs in a way that sounded dynamically more open and effortless.

One of the claims for the Lightstar is for excellent bass performance (footnote 3), so I spent some time checking this out. The Dunlavy SC-IVs have twin 10" drivers in a large sealed box: the bass they produce has the potential of being both extended and tight. The extension was fully there through the Lightstar, but, compared to the Threshold T-200 or the Bryston 7Bs, the bass wasn't quite as tightly controlled. The bass drum in the opening of Trittico certainly didn't lack weight or power through the Lightstar, but neither was it as crisp and focused as it was through the other two amplifiers (footnote 4). With speakers that have a more rolled-off bottom end than the Dunlavy SC-IVs, the Lightstar's added warmth would likely be more of an asset.

Finally, there's the matter of overall transparency/clarity. J. Gordon Holt, in whose definitions we trust, defined transparency as "freedom from veiling, texturing, or any other quality which tends to obscure the signal. A quality of crystalline clarity." I had some difficulty getting a handle on this aspect of the Lightstar's performance. There was no doubt that the Lightstar was good, but exactly how good was it? Comparable to the Threshold T-200, which I had thought worthy of Class A rating?

I did some controlled listening, comparing the Lightstar with the T-200 at matched levels (footnote 5), using track 1 of All-Star Percussion Ensemble (Golden String GS CD 005) and track 10 of Sylvia McNair's Sure Thing: The Jerome Kern Songbook (Philips 442 129-2). Conclusion: a close call, but I'd say the Lightstar falls short of the overall transparency offered by the T-200. In terms of the familiar visual analogy, it was as if the view through the Lightstar was slightly obscured—veiled, if you like—in comparison to the "crystalline clarity" of the Threshold. The difference was fairly small—smaller than, for example, the difference between the Mk.I and Mk.II versions of the Sonic Frontiers SFD-2 digital processor. (I had an early sample of the Mk.II on loan for one tantalizing weekend.) I should also note that the comparisons were done at moderate levels (peak sound-pressure levels just below 90dB); the outcome might be different at very high levels and/or with speakers that have a lower sensitivity.

Summing up
Whenever I hear of a new technology, I get excited by its potential, but wonder whether the technology, while perhaps solving one set of problems, will create another set. The Carver Lightstar Reference does represent new technology, but as far as I can tell, one with no significant sonic downside. The Lightstar performed with perfect reliability, without any operational quirks or untoward side effects deriving from its novel design.

The extremely powerful Lightstar has exciting dynamics and impressive bass response, and also possesses a considerable degree of finesse and subtlety. Having said that, I must admit that I ultimately preferred the superior transparency of the Threshold T-200 (which costs about 40% more and has only 30% of the power); but the solid, highly competent Lightstar may prove a particularly good match with speakers that are difficult to drive and which can use a bit of extra warmth.—Robert Deutsch

Footnote 3: The Carver Research white paper on the Lightstar's technology has a graph showing FTC-rated power output for the Lightstar staying constant down to 10Hz, whereas the power for a 300W "conventional amplifier" is shown as rolling off below 100Hz, falling to 1.5W by 10Hz. This supposed rolloff seemed much too extreme to me, so I called Carver for confirmation. A faxed letter from Jim Croft informed me that this was in fact a misprint: "the correct information would show that amplifiers that maintain full power down to just 20Hz will then start to roll off at a rate of about 3dB per octave" (ie, the output at 10Hz would be 150W, not 1.5W).

Footnote 4: In these comparisons of bass performance, the Lightstar and the Bryston 7Bs were in the balanced mode, the Threshold T-200 in the unbalanced. When driven by the Sonic Frontiers SFL-2 in the balanced mode, the T-200 has a significant bass rolloff.

Footnote 5: Actually, the discrete-step volume control of the Sonic Frontiers SFL-2 doesn't permit precise level-matching, so I "bracketed" comparisons, listening at slightly higher as well as slightly lower levels.

Bogolu Haranath's picture

"Blinded by the light" :-) ..............

georgehifi's picture

They've gota be the ugliest square waves I've ever seen from a solid state amp. With 1st overshoot ring on the trailing edge!!! What's that all about????

Cheers George

Anton's picture

I would be an avid reader of a column that “reviewed” vintage gear compared to current equipment. Yes, I know it would be tough making sure the gear was up to snuff based on age, but reading a comparison between a Sony CDP 101 and the current Rega would be fascinating.

Sign me up as a reader of the Anachrophile column!

Allen Fant's picture

Beautiful looking amp. While I never had an opportunity to demo a Bob Carver amp per se, I did have a wonderful audition, with his 1st Sunfire amp in 1996.