Thöress 300B monoblock power amplifier Page 2

A note about gain: According to Reinhard Thöress, the input sensitivity of his 300B amp is intentionally low, to prevent excessive preamp noise in systems that include the high-efficiency speakers with which most Thöress amps will surely be used. The amp's low input sensitivity has the additional benefit of allowing the user to operate his or her preamplifier volume control within a moderate to high portion of its range, where channel tracking is optimal—and that certainly proved true in my system.

The first thing that impressed me about the sound of the Thöress 300B was its exceptionally good sense of touch—a characteristic I noted with virtually every record I tried, not just those that have a lot of plucking and banging going on. For example, in Peter Maag and the London Symphony Orchestra's famous version of Mendelssohn's music for A Midsummer Night's Dream (LP, Decca/Speakers Corner SXL 2060), even the sounds of bowed violins exuded a very convincing intensity of touch. Of course, the Thöress also rose to the occasion with more overtly tactile material, as with the pizzicato strings in the second movement of Vaughan Williams's Symphony 4, performed by Sir Adrian Boult and the New Philharmonia Orchestra (LP, Angel S-36557)—and, even more so, with Art Taylor's explosive drumming in "Tanya," from Dexter Gordon's One Flight Up (LP, Blue Note/Cisco 84176).

Those recordings also showed off the Thöress's very good overall balance: It distinguished itself as a 300B-tubed amplifier with a little more treble extension than usual—which is to say, here was a 300B amp that did not sound entirely like a 300B amp—yet it was not in the least bright or harsh, and its bass registers were in very good proportion to the rest of the audioband, being neither too rich nor too lean. If you'll forgive a lapse into guitar-nerdism: In its evenness of response from the lowest notes to the highest, with no notes given short shrift or undue prominence, this amplifier brought to mind a very good Martin (or Merrill) OM- or 000-size mahogany-bodied flattop.

The Thöresses portrayed strings, woodwinds, brass, and voices with very good texture and color—the last not quite as rich or as saturated as the best I've heard, but more than merely satisfying—and did so in a context of exceptional clarity. In a reissue of the Borodin Quartet's classic recording of Shostakovich's String Quartet 8 (LP, Decca/Speakers Corner SXL 6036), the 300Bs made clear, in the opening bars, the distinctions between the instruments—especially the viola and cello—and allowed each a good measure of color and thrum. Dynamic peaks—especially in pizzicato passages, of which there is no shortage in this work—came across with considerable force, plucked violins in particular being tactile and punchy, and just slightly less crisp than through my Shindo Haut-Brion stereo amp. Also reproduced with great snap and touch were the sounds of harpist Marisa Robles in a 1966 recording, with George Guest leading the Choir of St. John's College, Cambridge, of Britten's A Ceremony of Carols (LP, Argo ZRG 5440). Except for a few traces of distortion that seem endemic to the recording itself—which is to say, I hear them through all gear—solo and massed voices were free of harshness and ripe with natural color. I also enjoyed the power and scale with which the harp's lowest registers were reproduced.

The Thöress's beautiful way with piano music was also a source of ceaseless fascination and joy. One of my favorite releases from the Electric Recording Company is Henriette Faure's recording, made in 1961 for EMI, of Debussy's Estampes and Book I of his Préludes (LP, EMI 350 C 004/ERC 006). The sound of the piano was ideal: colorful yet clear, with note decays as natural and unelectric as I've ever heard, the Thöresses seeming to work with my speakers to allow this recording of a piano to load the room as would the instrument itself. The piano's sense of scale was also wonderful, varying believably and becoming huge when needed—but not being oppressively huge throughout. I heard the same believable approach to scale with other, different-sounding piano discs, including Radu Lupu's 1973 recording of Beethoven's Sonata 21, Op.53 (LP, Decca Jubilee JB 105), and Wilhelm Backhaus's of the same piece (LP, London CS 6161).

Spatially, the Thöresses had the sort of room sound and "air" I would expect from amps with very good treble extension. They threw an impressively wide, well-detailed "stage" when playing such studio creations as "Pictures of a City," from King Crimson's In the Wake of Poseidon (LP, Discipline Global Mobile KCLP2), with excellent presence given Robert Fripp's electric-guitar solo near the beginning of the instrumental interlude. (I'm still giddy from having heard them perform this number during last year's Elements of King Crimson tour.) Orchestral music was also served well, and I enjoyed the sense of depth the Thöresses brought to Herbert von Karajan and the Berlin Philharmonic's recording of Brahms's Ein deutsches Requiem (LP, Deutsche Grammophon 2832 006). Additionally, the Thöress amps made clearer than usual the distinctions between different sections of the choir, the Vienna Singverein.

I made some direct comparisons between the Thöress 300Bs and my Shindo amps: the stereo Haut-Brion ($10,995, 20Wpc) and the Corton-Charlemagne monoblocks ($13,450/pair, 25Wpc). Some consistent differences emerged. Notwithstanding the greater crispness of the Haut-Brion (footnote 3), neither Shindo model is as extended in its treble ranges as was the Thöress, which gave the Thöress a better sense of sparkle, particularly when reproducing piano. Whether for this or some other reason, the Thöress also had a more transparent, "hear-through" sound, especially evident with densely scored classical music. Yet both Shindo models had a greater sense of drive that seemed related to their better reproduction of upper-bass/lower-midrange substance and body, as I heard when focusing on the cello and double bass in the Vienna Octet's recording of Schubert's Octet in F major (LP, Decca/Speakers Corner SXL 2028).

Other distinctions seemed related more to output power than to anything else, as I heard when listening to a recording of Bruckner's Symphony 9 by Carl Schuricht and the Vienna Philharmonic (LP, EMI ASD 493). This recording was spellbinding through the Thöresses, thanks in equal parts to their smooth clarity and the very good sense of touch they allowed plucked strings in particular—as with the pizzicato notes following the work's first big crescendo. On the downside, that crescendo was one of the few instances when the Thöresses' relative lightness, compared to the Shindos, made itself known in a less-than-positive way: In the tutti at that point, the instruments, especially the brass, had a bit more glare than they should. But harshness did not intrude on that or on any dramatic peak that I listened to with the Thöresses through either of my pairs of speakers. Differences between the Thöress and Shindo amps were more pronounced through the DeVore O/96s—which, while easy to drive per se, are not as easy to drive as the Altec Valencias. With "Chelsea Bridge," from Gerry Mulligan Meets Ben Webster (mono LP, Verve MG V-8343), the Shindo Haut-Brion did have more timbral substance, especially of the baritone sax and double bass. When I remade the comparison through the far more efficient Altecs, the difference was much smaller.

I have been wrong about lots of things. I was wrong about shawl collars and avocados and the Feelies and Ian Fleming and Mahler's Symphony 8, none of which I used to like. Now I love them all—especially the Feelies. I still dislike Mexican food and Wilco and the film Juno, but I suppose I'll retry them all every now and then. (Well, maybe not Juno: Life is too short for overpraised films with sitcom-caliber dialogue.) People change, and while it's good to be resolute on certain matters, I believe the need for flexibility increases as one ages.

Happily, after beginning my relationship with single-ended-triode amps with unconditional love, I can now find it in my heart to approach SETs with conditional love: Love the good, disregard the mediocre, curse the bad. (Unconditional love should always be applied to people, never to things.) And the Thöress 300B mono power amplifier deserves that love. It's a lively, colorful, tactile, well-textured, unambiguously musical amp that lacks any apparent flaws. It's well designed, well built, and resolute and forthright in its styling—altogether an heirloom-quality piece of gear. Highly recommended for anyone who has both the means and a sympathetic playback system.

Footnote 3: But see my "Listening" column in the February 2015 Stereophile.
Reinhard Thöress
US distributor: Audioarts, Inc.
210 Fifth Avenue, Suite 301
New York, NY 10010
(212) 260-2939

manisandher's picture

I've just received my Thöress 300B monos, set up by Reinhard to work with Elrog 300B output tubes. Feeding my Tune Audio Anima horn speakers (109dB/W@1m), I have to say I have the most satisfying sound I've ever managed to achieve in this hobby. I concur with Art's description of the sound, though the Elrog tubes are substantially better than the regular Full Music tubes.

Reinhard took a frequency response measurement of the amps before shipping them out to me. The measurement was taken on the PRIMARY side of the OPT, with a 5 Ohm wire wound resistor as dummy load across the secondary. (He believes this is the best way to take the measurement as the OPT secondaries do not carry a ground potential.)

The amps measure -3dB at 7.5Hz and 150kHz. Also, there is virtually no OPT resonance above 150kHz. Pretty good for a SE amp with zero feedback! And as I said, they sound utterly fantastic.