Tube Power Amp Reviews

Most of my listening was done with the Rogers EHF-100 on the top shelf of a borrowed Box Furniture Company D3S rack. Since it lacks a phono section, and because I listen much more to LPs than to CDs or digital music files, I supplemented the Rogers with a borrowed Leben RS-30EQ phono preamplifier (which I reviewed in the November 2011 Stereophile), preceded by step-up transformers from Silvercore and Auditorium 23. As I'm presently surveying the field of contemporary loudspeakers that share the better characteristics of vintage speakers, I was able to try the Rogers EHF-100 with a greater number and variety of loads than is usually the case around here: In addition to my reference Audio Note AN-Es, I also spent some pleasant hours using the Rogers to drive the DeVore O/96s and Line Magnetic LM755 Is (see "Listening" elsewhere in this issue). And, of course, my Quad ESLs.

During its time in my home, the Rogers amp performed without a hitch, although it exhibited a slight amount of mechanical transformer noise (inaudible from the listening area). It also ran rather hot, and for some reason its volume control became uncomfortably warm to the touch during listening sessions longer than an hour. That's a first for me.

Listening
The Rogers EHF-100 distinguished itself as a tight, punchy amplifier with loads of natural-sounding detail, the latter presented with at least some measure of the color and texture I associate with the best tube amplification. The Rogers also boasted a very wide bandwidth—I'll say more about that in a moment—and sounded distinctly open and clear with the right recordings.

I was especially impressed by the EHF-100's overall musicality—a word I mean literally, not as a coded term for a particular sort of tonal balance: Not only did the EHF-100 sound good, it did a better-than-average job of playing music. Lines of notes had very good momentum and flow, suffering none of the temporal distortions of lesser gear (of any price), while precision of pitch and the clarity of pitch relationships were both excellent. Simple melodies, as displayed throughout the 1973 recording of Schubert duets by Janet Baker and Dietrich Fischer-Dieskau, with pianist Gerald Moore (LP, Deutsche Grammophon 2530 328), sounded clear and beautifully involving through this amp; lines of less obvious sense—drop that needle pretty much anywhere on Xenakis's Metastasis, by Maurice Le Roux and the French National Radio Orchestra (LP, Vanguard VCS 10030)—seemed as clear and purposeful as one might reasonably hope for.

Pop recordings were also musically well served by the EHF-100. With "Going Home," from Leonard Cohen's Old Ideas (AIFF file from CD, Columbia 88697986712), the EHF-100 seemed to highlight to good effect the contrast between the humanness of the lead vocal and the artifice of its electronic surroundings. On that recording, the Rogers amp also sounded a bit more crisp—not unpleasantly so—than my combination of Shindo Masetto preamp and Corton-Charlemagne amps, with deeper bass as well. The latter quality made itself especially known in the album's next selection, "Amen," where a low D-flat (34.65Hz) played on a synthesizer sounded exceptionally full and strong. (Good output transformers, I would imagine!) But with louder and more densely recorded pop tracks, such as the dB's great new album, Falling Off the Sky (CD, Bar None BRN-CD-210), voices and instruments emerged from the mix somewhat less well, the midrange seeming a bit recessed in comparison to the bottom octaves.

The Rogers amp was exceptionally good at spatial effects. The interesting recording by Eugene Goosens and the London Symphony Orchestra of Rimsky-Korsakov's Scheherazade (LP, Everest 3026), with its very distant-sounding solo violin—so distant that it sounds like a recordist's mistake in some passages, particularly the beginning of the fourth movement—gave the EHF-100 a chance to show off its excellent sense of depth. And the Rogers provided a wonderful sense of sonic perspective when playing the famous recording, by Georg Solti and the Vienna Philharmonic, of Wagner's Siegfried (LP, London OSA-1508). This was especially true in Act II, with various sounds—birds, hunting horns, a dragon, and Siegfried himself (tenor Wolfgang Windgassen)—all seeming to originate from different portions of the stage in terms of both lateral placement and depth.

Notwithstanding its generous output power, the Rogers amp sounded at times a little dynamically constrained—an observation having more to do with naturally recorded acoustic music than anything else. In the recent reissue of Ernest Ansermet and the Orchestra de la Suisse Romande's recording of Tchaikovsky's complete Sleeping Beauty (LP, Decca/Speakers Corner SXL 2160-1-2), the Rogers had sufficient treble extension, yet the highest notes carried by the flutes and the violins lacked texture and touch compared with my reference electronics. And while pizzicato strings played at the loud end of the dynamic spectrum came across with some force, they nonetheless lacked dramatic contrast with the sounds of the other players.

A word about bass extension: As I hinted above, the EHF-100 wasn't the least bit bass-shy. The electric bass in "The Golden Age," from Beck's Sea Changes (LP, Geffen B0004372-01), was considerably deeper than through my Shindo amp, as well as being pleasantly substantive: Notes and percussive sounds in the lowest register weren't merely puffy, airy suggestions of bass, but had real flesh and blood. That said, by the album's next selection, "Guess I'm Doing Fine," I began to wonder if perhaps the EHF-100 was giving undue prominence to the two lowest octaves. (Then again, for some of us, this is like wondering if perhaps the local ATM is providing too much cash.) I was never troubled, and in fact I very much enjoyed the Rogers' consistently clear, musical bass—but bass-phobic listeners and sticklers for perfectly flat response should consider themselves forewarned.

Conclusions
In my 28 years of writing professionally about domestic audio, I've reported on the products of literally scores of startup companies. None of them has approached, let alone matched, the level of professionalism evident in the Rogers High Fidelity EHF-100. From its design and construction through its packaging and documentation, this amp is among the most mature products I've had the pleasure of testing, from a company of any age.

And I was pleased with the sound of the EHF-100. The Rogers amp wasn't as nuanced, colorful, or dramatic as my Shindo separates; then again, at approximately one-third the price, I wouldn't have expected it to be. By the end of the review period, I was impressed that the Rogers offers very good value for money in terms of musical and sonic performance—and very good value considering the quality of its parts and construction. With this amp, Roger Gibboni has single-handedly disproved the notion that a new American electronics manufacturer can succeed only by serving the luxury end of the market. The Rogers EHF-100 is more than just good sound and good value: It's good news. Very highly recommended.