November 2009

World Premiere!
JohnBlue TL66 Monoblock Tube Amplifiers
They reproduced music. It is just as plain and simple as that.
Review By Tom Lyle
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  One would think that I'd be more on top of things, but as I was wrapping up my review after I had the 6 Watt per channel JohnBlue TL66 monoblock amps in my system for about two months, I finally learned that JohnBlue designs and manufactures a single-driver stand-mounted speaker called the jb3. Needless to say, I have no doubt these speakers would be a perfect match for the JohnBlue TL66 amps. Even though I was well aware that it might upset both the low-powered-amplifier mated to the full-range/single-driver speaker crowd (and perhaps JohnBlue as well), instead of requesting a pair of jb3 speakers I continued with my review using the Coincident Speaker Technology's (CST) Triumph Extreme Signatures I reviewed in May 2009. They are an efficient (94dB/W/m), impedance stable (a flat 8 ohms), two-way that CST says are designed for use with a variety of amps, and in their literature claims that these speakers can be used with those rated as little as 3 Watts.  So it follows that if the TL66s were any good they would:

1) Bring out the best in this speaker, and thus,

2) Bring out the best in the music.

If you read my review of the extremely transparent sounding CST speakers, it should not be that much of a surprise that answer in both cases was a resounding yes.

My main system has always been built around solid-state muscle amps and large inefficient speakers. Yet all the while I've maintained a second system designed around stand-mounted speakers that made the power amp's power specifications less of an issue. Since I still had the CST Triumph ES's in this system I thought it would be a perfect opportunity to seriously audition the JohnBlue TL66 class-A single-ended beam tetrode monobloc amps manufactured in Taiwan that I read about in Enjoy the Music.com's report of the 2009 Munich High End Show.

Purity
The modest looking TL66 sports only two vacuum tubes on its cageless cabinet. Designer and founder Tommy Wu's philosophy of combining purity with first-rate components doesn't leave much room for him to skimp on the quality of the constituents of his products. For instance, instead of supplying standard Chinese or Russian tubes the TL66 uses New Old Stock (NOS) circa 1980s mil-spec OTK 6L6 for its power stage and NOS Sylvania 6AU6 driver tubes for the input stage, and to avoid interference between the tubes JohnBlue uses 6.3V of AC power for the 6L6 and the 6AU6 to improve isolation. And of course these amps are point-to-point wired without the use of any printed circuit boards, and even more noteworthy, the output transformer is hand wound by K.E. Lee, the inventor of the Litz winding technique.

The hand-made TL66's internal parts use a mixture of audiophile-grade German, American and Japanese parts. NOS Frako capacitors originally made in East Germany are utilized, and horizontal champagne and gold-colored audiophile Frako and Roe caps that are often seen in Studer components commonly found in pro recording studios. JohnBlue says that using a combination of these is wise because although Frako and ROE capacitors are sonically alike, Frako is less bright than ROE caps, and Frako is renowned for its "midbass punch and subtle airiness". The aqua-blue main coupling caps are proprietary, and have been dubbed "Mr. Cable" by JohnBlue. The volume pot is a Japanese blue shelled Alps , and the AC Power filter caps are manufactured by Hitachi , but as an option one can order BHC/Rifa filter caps. The TL66 uses carbon and Allan Bradley resistors, pure virgin and OCC copper wires for the internal wiring, and Wonder Solder for all contacts and lead points. JohnBlue encourages customers to tube roll, and the amp is capable of accepting KT88, 6550, EL34, or KT77 as substitutes for the supplied 6L6 output tube.

Along with the CST speakers mentioned above, the simple system in which the JohnBlue amps resided included the digital source of an Arcam CD player, which near the end of the review was connected to an Acousticbuoy digital-to-analog converter, and very late in the review period I used an Oppo universal player. The sole analog source was a vintage AR tuner. Both tube and solid-state preamplifiers were mated with the JohnBlue, including those made by Balanced Audio Technology of the later type, and Burson Audio and Acousticbuoy of the former. Interconnect and speaker cable was by Cardas, and all the equipment in the system was connected to a Panamax 5510 power conditioner. Even though each TL66 monoblock has its own volume control enabling a source to be connected directly, I had better results using a preamplifier with the volume on the power amps set to maximum, so that's the context in which this review was written.

Transfixed
OK, so I mentioned JohnBlue designer Tommy Wu's philosophy of wishing to combine purity and first-rate components when building these amps, well, that's how his TL66s sound, as they combine purity with first-rate performance. I'm not just saying that to be clever – I was transfixed the moment I turned on their power and put some signal through them, listening to the FM tuner – on a classic rock station no less. I could here the compressor/limiters at the station breathing in and out whilst the music played, and sat engrossed while they broadcast the live version of Wings' "Maybe I'm Amazed" from Wings Over America, followed by Deep Purple's "Smoke On The Water" from their Machine Head CD. Then, as my sanity gradually returned, I turned the dial to the jazz station WBGO. It has a signal that's among the best I've ever heard from FM (not to mention that the 4500 Watt transmitter is only about ten miles from my home), and took notice of colorless solo instruments and voices float between the speakers. The sound was not bound to the speaker cabinets, and if you've read my review of the CST speakers this trait should sound familiar. Yet it was more than that – as if I could imagine I was listening to a direct feed from the radio transmitter, bypassing the tuner completely. OK, that last statement might be a bit of an exaggeration – but even so, I shouldn't waste too much time talking about this incident; of course FM listening is an off-axis activity in our home. So I turned to a selection of silver discs for some serious sit-down time with these amps.

I had a bit of trouble when organizing my listening notes for this review since in many cases the usual lexicon commonly used by audiophiles didn't apply to the sound of the combination of the JohnBlue amplifiers and the CST speakers. Things such as "imaging" and "soundstage" were replaced by a sound that was just "there" – that is, sound just filled the room with a zone of sound that was, in basic terms, a truthful version of the original event that was recorded by the microphones at the recording session. Rarely does one exclaim at a live performance or recording session, "what a wonderful soundstage!" Yes, there was a very large soundstage that was occupied by images of instruments and groups of instruments, and these images were separated by what seemed like a country mile, especially given that it was being generated by two-way speakers.  Combined with these amps' superior transparency, it not only set them apart from the average piece of gear, but also the average hi-fi listening experience. Added to these traits was the realism that occurred when playing well recorded discs. There was practically a direct-to-source transparency that transpired on organist Larry Young's 1965 Unity album on Blue Note's RVG re-issue series.

When Elvin Jones' rode the bell of his cymbal on "Zoltan", a tune written by trumpeter Woody Shaw, the resulting ring didn't seem like it was emanating from a speaker's driver, but just filled the space around the right speaker. But I'm sure you've heard that sort of description before, yet the sound wasn't just one that almost defied analysis, it combined both the sound of the instrument, the room in which it was recorded, and the tiny amount of added reverb that created that portion of the view from the sonic window into the session at Rudy Van Gelder's studio. I can't believe I just wrote two long sentences about the sound of a cymbal. Of course, more importantly, the same was true for solo instruments such as Joe Henderson's distinctive tenor sax as it infused the air of the not only the side of my 11' x 18' x 8 ½' listening room in which the speakers were located, but enveloped the listening position as well. As Shaw's trumpet and Henderson's sax played in unison during the theme of the up-tempo "Beyond All Limits", another of Woody Shaw's tunes, even though the outlines of their two instruments wasn't drawn as sharply as some higher-priced spreads that I've auditioned, it was still quite remarkable. And underneath it all Larry Young vamped tastefully, even as he performed bass duties with his foot pedals. The TL66 admirable mid-bass response let me hear exactly what was going on.

On a 2004 CD of works by Steve Reich performed by the Orchestra National de Lyon conducted by David Robertson, the massed strings on "Triple Quartet for String Orchestra" in an arrangement using three quartets, and then tripling each instrument in each of those quartets, produced a lush wall-of-sound that was very Reich-ian and sounded as if it saturated the hall of the Auditorium at Lyon. It definitely showed off the TL66s midrange prowess and was at least as good as I would have hoped for in a vacuum tube powered amplifier. Even though parts of the score required the musicians to play in unison, there were still dynamic shadings and interactions between the players in the piece that kept things interesting. Like on a good Bach piece, this selection held up to repeated listening sessions because each time the interplay between the instruments created new patterns. Though not a piece of music I'd want to listen to every day, the combination of the JohnBlue/CST made this music as involving as I've ever heard it.

Switching musical gears to rock, Nick Cave and The Bad Seeds recorded the basic tracks for their album The Boatman's Call at Abbey Road studios, and I think that might at least somewhat contribute to the fact that this disc's sound quality is one of the best in The Bad Seeds large catalog. "Lime Tree Arbour" features only three members of the group, Mr. Cave on piano, vocals, and Hammond organ, Nick Harvey on bass guitar, and Thomas Wydler on drums. Through the system the multi-tracked recording is laid bare, my notes just again say "it sounds THERE". There was a patent truthfulness not only to the source, but to the music itself. As the drummer lightly raps his kit, the rest of the band frames Mr. Cave's dolorous voice as it he delivers his jeremiad: "there will always be suffering/it flows through life like water" making it sound like a love song rather than a lament. The JohnBlue TL66 communicated not only the excellent sonics on this studio recording, but the meaning behind the music.

The JohnBlue/CST transparency let me easily hear changes made upstream, not just the sound of the CD player that was being used. Now, please understand that I think Arcam makes very good products, and the player that I used upsamples to 192 kHz, and is a great piece of equipment. But just as easily as I could be fooled into thinking that I was peering into a miniaturized sonic window of the original recorded event I could also hear the sound of what that particular CD player was contributing to the overall sound when I tried other players. That was also true when switching cables, or lifting disc transports with vibration control devices, well, any small change in the system, really. But like I said, I could just as easily forget about all the hi-fi concerns and just sit back and bask in the music. So it was definitely time to hook up a player that was capable of playing SACDs.

The SACD of Eric Dolphy's Out There sounded spooky-real in that each instrument not only occupied its own place in the wide and deep soundstage (I should have put quotes around "soundstage" because of its rather ethereal nature, but you know what I mean), but as it did this the sound of the room in which it was recorded could clearly be heard. It wasn't just the spaciousness, despite any studio baffles that were placed between the instruments the system's resolution made possible to hear that each instrument's mic still picked up sounds from the others, and that sound could also clearly be heard. I don't want to imply that the very life-like sound emanating from the speakers was indistinguishable from the real thing, that would be a stretch, but all the sonic cues that make this a landmark album were obvious. The straightforward (although some might say primal) quality of Ron Carter's bowed and plucked cello combined with surprisingly adept classical technique sounded especially introspective, and of course Eric Dolphy singular style was evident. But this hi-rez disc clearly demonstrated the JohnBlue/CST combination was maybe not quite a combination made in audio heaven, but was so ultra-transparent to the source that one will surely be rewarded by using the best upstream equipment one can afford when using a pair of speakers that can take advantage of the TL66s strengths.

Transcended
Perhaps JohnBlue's North American importer Obad Imports purposely didn't tell me about JohnBlue's single-driver jb3, figuring that I'd know very well what type of speakers to pair with the TL66s. The Coincident Technology speakers that I used for this review were certainly a perfect match, and showed that the 6 wpc TL66 performs superbly when dancing with the right partner. The JohnBlue TL66 had its limits of course; if pushed too hard while playing power orchestral or heavy metal with the volume too high, the sound compressed a bit. It is after all, only a 6 Wpc amplifier. And even though I was initially shocked how close it came to the limits of the frequency range of the speakers, it didn't have the nth degree of bass and treble extension. But this amp transcended these relatively trivial observations, especially when one assumes that it will be paired with super-efficient speakers that will rise to the challenge, and thus these drawbacks will be made pretty much inconsequential. I have to admit that throughout the review I had a bit of trouble describing the sound of these amps, but to summarize, the JohnBlue TL66s made music – it is just as plain and simple as that.

Specifications
Type: Monophonic vacuum tube amplifier
Output Power: 6 Watts per channel
Tubes: Two OTK 6L6 and two Sylvania 6AU6
Frequency Response: 35 Hz to 20 kHz (±1.5dB) 
Distortion: 1% 
Signal To Noise Ratio: ?85dB 
Input Sensitivity: 450mV 
Input Impedance: 100K ohm 
Output Impedance: 8 Ohms
Dimensions: 10.25 x 5.75 x 5.25 (LxWxH in inches) 
Weight: 28.5 lbs.
Price: $2188 per pair

Company Information
JohnBlue
No. 30 , Chenghe Street
Huwei, Township,
Yunlin, County 632
Taiwan (R.O.C.

Voice: +886 05-631-2431 
E-mail: sale@johnblue-audio.com

United States Distributor
Obad imports
Unit A, 1300 Boblett Street
Blaine, WA 98230

Voice: (778) 968-3044 
Fax: (604) 677-5694
E-mail: sasha@obadimports.com
Website: www.obadimports.com