Review: Tempo Electric / Arthur Loesch 1.1 Control Preamp Tube preamp
Although my involvement with audio goes back 40 years to my college days, I’ve only occasionally felt compelled to upgrade or make major changes in my home system. In those four decades, I’ve only owned about four different sets of preamps, amps, or speakers.
I actually grew up with tubed audio in the form of my parents’ Magnavox console radio, with a built-in 78 RPM record changer. When I went to college, I purchased a Dynaco SCA-35 integrated amp, an AR XA turntable with a Shure cartridge, and a pair of AR 4x speakers, all for about $300. Big money for the time (1966), but it kept me happy for over a decade. In the late 1970's, I was introduced to the Audio Underground in the form of The Absolute Sound and Stereophile, publications that at the time accepted no advertising and whose writers conducted a lively dialogue about all things audio. Over the next decade, I made cautious upgrades to NYAL and conrad-johnson electronics, as well as Magnapan and Thiel speakers. Some years later, when those journals became the mainstream, I discovered Joe Roberts’s Sounds Practices, the voice of the new underground. At a time when mega-watt amps drove power hungry speakers, it was a glimpse into another world that was engaged with micro-watt, triode amps and highly efficient horn-loaded speakers.
An article in Sound Practices, which featured a tour of several of these unusual systems, all within the central New York State area where I live, intrigued me. One system was completely designed and built by Prof. Arthur Loesch, a physicist who taught at the State University in Albany, NY. Although Dr. Loesch was too busy with academic research to manufacture his own designs for others, he was in the habit of consigning their fabrication to a circle of friends and, though a somewhat circuitous route, I was put in touch with Jon Baier, an engineer in Schenectady. For about $1K, Jon put together a “black box” phono preamp, based on an early Loesch design. It used a trio of 6DJ8's per side for the gain stages, as well as a separate solid state power supply that originally came as a kit, appropriately called “Mr. Power.”
This was about 1992 and Mr. Power was eventually replaced by a pair of vintage, tubed General Radio 1201-B units, purchased for $50 each at an electronics surplus warehouse in Utica (now gone). These were adapted for the Baier preamp by John Wiesner, to whom Dr. Loesch later delegated the building of his electronics.
It was around 2001, when I saw an ad in Art Dudley’s Listener magazine, another standard bearer in the Audio Underground, for a revised version of the Loesch preamp to be built by Tempo Electric in Saratoga Springs. This turned out to be a partnership between Dr. Loesch and his friend Joseph Levy. Joe succeeded John Wiesner when the latter could no longer find any General Radio power supplies and decided that making the preamps to a price point of about $2.5K was no longer practical. Levy’s idea was to work with Dr. Loesch to refine and max out the design, construct them in a more consistent fashion, and make them available to a wider audience.
Still happy with my Baier-built preamp, I put myself on the Tempo mailing list and waited for news. About once a year, an e-mail would arrive with occasional updates, but it wasn’t until the beginning of 2008 that the long-awaited, newly revised, Loesch preamp was available for purchase. I auditioned one at Joe’s Troy, NY, demo room and left a deposit. About six weeks later, the new Loesch preamp arrived, customized with a few upgrades, including low noise, tightly matched, Western Electric 417A’s in place of the stock Raytheons (which sounded pretty good, too).
Like my older model, the new one had a dedicated audio unit, designed around three gain stages, plus a pair of tubed power supplies, one for each channel. The Tempo / Loesch audio stage included dual-mono, ladder-type volume controls and a selector switch to choose between Phono, Active Line, and a pair of Passive Line inputs, as well as a Mute position. Because of the mechanical limitations of the rotary switches used, a remote control is not available. While there is no mono / stereo switch, a pair of extra outputs on the back can be bridged with a dedicated interconnect to blend both channels, eliminating the need for another switch. All in all, this is a minimalist design, housed in a set of anodized aluminum chassis, and geared toward the purest who values the best sound possible over the usual bells and whistles.
In the updated power supplies, the diodes found in the 50-year-old GenRads were replaced by a slow turn-on 5V4 tube rectifier and there was a much higher grade of modern parts throughout. Looking inside the main audio stage, the trio of 6DJ8's had been changed to a 417A, 6GK5, and 5687. All of the tubes, including those in the power supplies, were NOS American or British, rather than new production. The passive parts, too, were a mix of exotic caps and resistors, mainly brands or types that audiophiles often use to replace stock. These included VCap Teflon and REL Polystyrene capacitors, Caddock MS power resistors, “Naked” Vishay and Audio Note resistors, as well as pure silver wire in the signal path, and so on. The Loesch philosophy is to integrate a wide variety of high-quality parts as required, in order to cancel out whatever sonic signature they may otherwise individually impart. This is in contrast to the Baier / Loesch preamp which, in additional to being all 6DJ8, used many similar branded caps and resistors throughout.
Apparently, one of the reasons it took so long to get this unit to the marketplace, was Loesch and Levy’s obsession with recreating the sense of liveness from any given recording. I was told that in voicing the preamp, the main references were live performances, both on LP and CD, with an emphasis on acoustic instruments and vocals. Overdubbed recordings were generally omitted from the listening and evaluation sessions, though non-multi-tracked studio sessions were allowed for evaluation purposes.
My wife and I are regular concert goers, enjoying both classical and popular music. We probably attend 30 or 40 performances a year, sometimes at festivals, from chamber music to blues and jazz, where we can hear two or more in a day. I feel safe in claiming to know what live music sounds like. So, for me, getting the feel of a live performance right is a critical factor in my assessment of any piece of audio gear and one reason that I so rarely upgrade.
As an aside, I should mention that in addition to the Tempo / Loesch preamp, the rest of my system is also a mix of DIY and custom gear. Bitten early on by the Sound Practices bug, this includes a pair of 10" Tannoy Gold drivers mounted in Jean Higera’s Onken cabinets, a pair of DIY 300B SET amps (also based on a Loesch design), and a Well Tempered Reference turntable and arm with an early, pre-Lyra, DaCapo cartridge sold under the Mørch brand. A few months ago, I replaced the the latter with a MoFi Carbon 3.5.
Back to the Loesch preamp. Comparing the Baier with the Tempo Electric versions wasn’t quite apples and oranges, but more like home cooking vs. gourmet. After years of dining on Mom’s best fare, it was like being served by Tom Colicchio or Wolfgang Puck. The Baier was still a good performer with the ability to convey that elusive sense of musicality, but the Tempo version put the musicians in the room. As people in the theater would say, the fourth wall disappeared. Listening to live performances in halls that I was familiar with, I was more aware of the ambient cues that define those spaces. For example, recordings made in Carnegie Hall clearly sounded different from those made at Chicago’s Civic Opera or New York’s Avery Fisher. Even studio recordings took on a different life. Listening to a 1960 collection of Perez Prado’s big band mambos on RCA, it was easy to tell when the band was recorded in one studio or another (or perhaps with different microphones).
In fact, the whole sound stage took on a new perspective. Listening to an LP of Count Basie performing live at the Village Gate, I could now clearly hear all of the chatter going on simultaneously at dozens of little tables, all in virtual 3-D (and this with only two speakers). If it weren’t for their sheer number, it would have been easy to follow the individual conversations. Basie and the individual instruments were clearly defined on stage, as well. On Miles Davis’s "Kind of Blue," I could not only hear Miles’s tongue articulating into the mouthpiece of his trumpet, but for the first time, I could also make out the resonance of this articulation inside the trumpet, itself. Want to finally make out the lyrics that Rickie Lee Jones is whispering on "Girl At Her Volcano"? This is the preamp that will do it. One could go on and on with similar examples. But once one gets past the startling aspect of hearing long familiar records as if they were being played for the first time, one simply gets swept up into the music.
If I can find any fault with the Tempo / Loesch preamp, it’s that its ability to deconstruct a recording is not always for the better. Among the ones that suffered were a vintage Sarah Vaughan LP, billed as recorded live in Chicago. With the Tempo / Loesch, it was easy to tell that regardless of where Sarah might have been, the band was clearly playing in a different space, at a different time. A stereo reissue of The Byrds’s "Sweetheart Of The Rodeo" on Sundazed sounded like badly remixed, over-dubbed garbage. I had to go back to an original mono example to enjoy it, again. But these were rare exceptions. The vast majority of LP’s were elevated to a much higher level than I ever imagined possible. Every performance took on its own personality. Every recording was distinct in its own way. There was always a nice balance from top to bottom, with no part of the sound spectrum drawing undo attention to itself.
By contrast, a colleague had a Wavestream phono stage on loan and brought it over to compare. Because the Wavestream does not have volume controls, we fed it into both the active and passive line inputs of the Tempo / Loesch. The active line circuit ads about 14 dB of gain in a single stage, while the passive inputs bypass the electronics altogether, sending the signal directly to the volume controls. Either way, the main difference was immediately apparent. While the Wavestream was a smooth performer, all of the ambient spacial cues simply disappeared. Regardless of where the performance took place, every recording sounded like it was made in an anechoic chamber. Pleasant, but homogenized.
A few months ago, I returned to the Tempo Electric demo room and was present at a shoot-out in which eight or so vintage and modern phono cartridges were compared. The oldest was a Fidelity Research FR-1 Mk3f (1977) and the newest, a current production Mobile Fidelity Carbon 3.5 (built by Miyabi Labs). In between were a Signet TK10 ML (a top Audio Technica MM from the late 1980's), my Mørch DaCapo (mid-1990's), a Monster Cable Alpha Genesis 1000 (1987, designed by the current maker of ZYX carts), and a 1980's vintage Grado 8MZ. Those of us familiar with the sound of each brand or designer, had no trouble distinguishing one from another.
To summarize, this is one preamp that clearly has no coloration or self-imposed personality, other than faithfulness to the signal that’s fed into it. It reveals all. It is distinguished by lack of glare in the higher frequencies, a cleanly balanced bass and midrange, a knack for unraveling an extraordinary amount of detail, and the ability to completely envelop you in the musical performance. If the rest of your system and ears are up to it and your recordings are true to the music, then this is the preamp against which all others have to be measured. The more I listen to other preamplifiers and phono stages, the less desire I have to change. Given the price (beginning at $7.5K, but closer to $10K, as I bought it), it’s competitive with CAT, Herron, Manley, Aethetix, ARC, conrad-johnson, and a host of others. Even though I only upgrade about once in a decade, this is still the last phono preamp I ever expect to buy.
Well Tempered Reference Turntable and Tonearm
Mørch DaCapo Cartridge
Mobile Fidelity Carbon 3.5 Cartridge (I was so impressed at the shoot-out, that I had to buy one)
300B SET Amps (DIY derived from an Arthur Loesch design)
10" Tannoy Gold Speakers in custom-built Onken Cabinets
DIY Silver Interconnects and Speaker Cables
AR XA Turntable and Tonearm
Rotel RP-900 Turntable and Tonearm
SOTA Comet Turntable with Profile II Tonearm
Shure V15 Type II Cartridge
Grado 8MZ Cartridge
Madrigal Carnegie II Cartridge
Dynaco SCA-35 Integrated Amp
New York Audio Labs NB1 Preamp
conrad-johnson PV-2 Preamp
Arthur Loesch 6DJ8 Preamp (Built by Jon Baier)
NYAL Moscode 300 Amp
conrad-johnson MV-75 Amp
AR 4x Speakers
Maganapan MG-II Speakers
Thiel CS-3.5 Speakers
Fulton Brown Speaker Cables
MIT, Spectral, and Kimber Interconnects and Speaker Cables