Miyajima Lab Wo-1 preamplifier Tube Amplification Moves West

Sidebar 1: Tube Amplification Moves West

In the mid-1960s, as solid state amplifiers and acoustic-suspension speakers gained popularity in the US, low-power tube amplifiers and horn-loaded loudspeakers were abandoned. The recovery started almost immediately. Tube amps reappeared in the early 1970s, from Conrad-Johnson and Audio Research, followed by Cary Audio and others in the '80s. One of Julius Futterman's OTL (output transformerless) tube-amp designs from the mid-'50s (footnote 1) was reproduced by Harvey "Gizmo" Rosenberg (footnote 2) of New York Audio Laboratories in the form of the Futterman OTL-1 power amplifier. Rosenberg's hybrid tube/FET amplifiers and preamplifiers (footnote 3), and his gift for showmanship, made him a prominent audio influencer. Sumiko cofounder David Fletcher and Auditorium 23's Keith Aschenbrenner imported tube amplifiers from Japanese brands, and in the early 1990s, Peter Qvortrup of Audio Note UK marketed his tube amplifiers in the US as luxury goods, paving the way for contemporary luxury audio.

Audio magazines played a role as well, influencing the nascent tube amplifier sector in the US. In the early 1990s, Walt Bender's newsprint circular, Audiomart, and Japan's MJ and The Tube Kingdom magazines inspired a burgeoning cottage industry of DIY tube amplifiers in the US. The Japanese influence was strong. Joe Roberts started up his influential Sound Practices magazine in 1992.

Among the writers for Sound Practices were JC Morrison, Don Garber, Nori Komuro, Gordon Rankin, and Stereophile's own Herb Reichert—members of a maker community dubbed the "Triode Mafia," which grew out of Garber's Soho shop, Fi. The Triode Mafia experimented, invented, and designed many tube amplifiers.

"When Garber opened his store, I had just closed my Eddy Electric business, which imported Tango transformers and Black Gate capacitors," Reichert recalled in an email. "Garber and I met on a construction site at 500 Park Avenue. We shared a deep love for George Jones, so I invited him to my place and played 'He Stopped Loving Her Today' with some old Altec A5s and Flesh & Blood monos. After 30 seconds of George, Garber was in tears and completely 'got' what the triode-horn thing was trying to accomplish. He knew JC was into this too, and almost instantly Don was all in. That was the start.

"We were all seeking the simplest and the purest way of making audio that was direct and coercive and revealing of the human aspect of recordings," Herb continued. "Arthur [Loach] and [Nori] Komuro's smarts were a radioactive force that drew people like Gordon Rankin, Dick Sequerra, and Tim de Paravicini into the scene.

"... It all began at Fi. Fi was a crucible."—Ken Micallef

Footnote 1: See Julius Futterman's story at jacmusic.com/techcorner/ARTICLES/English/Harvey-Rosenberg/futterman.htm.

Footnote 2: Harvey "Gizmo" Rosenberg passed away in July 2001.

Footnote 3: Read more on Dr. Gizmo's hybrid amplifiers at meta-gizmo.org/Tri/nyal/moscode.html.

Miyajima Laboratory
4-3-25, Chayama, Jounan-ku
Fukuoka City, Fukuoka, 814-0111

Ortofan's picture

... falling on his sword.

How does an ill-performing, if not outright defective, product such as this one ever get released to market?
Is this a typical example of "unique hand-made artisanal" electronics?

With $21,500 to spend on a tube-type preamp, I'd be heading to a McIntosh dealer to buy a C2700 - and with the money leftover, an MC1502 tube-type power amp.

Glotz's picture

Very disrespectful.

When's your preamp coming out?

Ortofan's picture

... the output acceptable to you?

This product should have stayed in the "laboratory".

It reminds me of an incident related by a member in a speaker manufacturer's forum in which a tube-type preamp had failed by generating a significant DC voltage at the output. The preamp was connected to a DC-coupled solid-state power amplifier, which amplified the faulty DC signal from the preamp and sent it to the speakers, thereby burning out the woofers. The cost of the replacement drivers was several thousand dollars. The speaker manufacturer would not cover the cost under warranty since it was due to the faulty preamp. The preamp manufacturer's warranty only covered the cost to fix the preamp. After it was repaired, the owner traded-in the preamp for a solid-state model and traded-in the power amp for one that was not DC-coupled.

Glotz's picture

Wow, you really have a complete, selfless dedication to consumer affairs, especially across the entire internet.

To the designer, not so much. This issue you speak of to his design is not the same mfg. you elucidate above, correct?

Your circuit point is valid, yet your methods of communication not so much. The way you go about your points are consistently disrespectful & repulsive (esp. for someone who hasn't tread upon you personally).

Caveat emptor. The stuff lawsuits are made of, esp. for well-heeled audiophiles.

Ortofan's picture

... all of the time.

First, JVS objected to the use of hyperbole.
Then, someone else objected to the use of metaphor.
Who's next to be offended by the use of a literary device?

Glotz's picture

This goes well beyond a literally device for someone Japanese.

I get it: your disgust and indignance needs to have a snappy literary device for extra effect. Internal snickers and all that.

rwwear's picture

Wouldn't that be a conflict of interest?

Glotz's picture

It was said facetiously. His criticisms were not unfounded, but the method of delivering them was...

Nirodha352's picture

Or Zanden which should have been included in this review for several reasons

Kursun's picture

It is a good practice to switch on the preamplifier first, then the power amplifier. But this is too much!
One false move and your loudspeakers are fried!
I wonder why they at least didn't put a delay circuit at its output.

I would also have preferred to see hermetically sealed micro relays as input selectors. The classical mechanical input switch would oxidise and wear out in a few years and start emitting annoying noises.

kai's picture

There‘s no general rule that relays have superior longevity to mechanical switches.

A well capsuled an greased switch can last forever.
On the other hand I’ve seen loads of failing relays during my career.

When the switch that controls the relay fails, the whole thing doesn’t work any more.

Kursun's picture

Well before the switch completely fails, it starts its noisy operation and keeps like that for years.Since it is on the signal path you'll hear its every stage of degeneration.

Absolute longevity is not the most important factor.
Signal passing without any degeneration is.
An old mechanical switch contacts may even act as diodes.

Mikke's picture

... the primary objective is "Primum non nocere".This is the physician's duty to first and foremost to avoid harming the patient during the treatment.
I did not know that such an objective should be relevant in the audio business. Apparently it is.
I think I´ll stay true to my trusty solid state preamp.

Lars Bo's picture

Thanks, Ken.

The Miyajima Wo-1 is, to me, one of the most interesting preamps out there, and it has been high on my "SP-review wanted list" for years (personally, I only have a full experience with two Miyajima cartridges and a SUT).

Your quote of Miyajima's goal - i.e. to convey musical sound so faithfully that the personality and emotions of the artists are perfectly expressed - seems to be in tune with a distinction between an instrumental and a terminal goal of the "inventor" of High Fidelity, engineer H.A. Hartley. In 1958, he wrote:

"I invented the phrase "high fidelity" in 1927 to denote a type of sound reproduction that might be taken rather seriously by a music lover. In those days the average radio or phonograph equipment sounded pretty horrible but, as I was really interested in music, it occurred to me that something might be done about it."*

In contrast, many a modern definition of high fidelity doesn't include the concept of music and/or musical(ity) whatsoever. Hartley's vision, however, almost a century ago, was to bring the essence of a musical experience home, by, though not exclusively, applying science and technique in sound reproduction. The terminal goal of high fidelity was to convey the "it" that drives humankind to music in the first place. Hartley elaborates, on a fact and a consequential primacy (as he saw it... but, hey):

"Perfect reproduction of an original performance in an auditorium cannot be achieved in the home. The esthetically equipped expert can only strive to provide a standard which is musically satisfying. This phrase is introduced deliberately, because, when science has done its best, the ear itself is the final arbiter and, when the engineer has done as well as his technique will allow, he must then apply the principles of musical criticism to what he has accomplished."**

Noriyuki Miyajima certainly appears to expertly apply such principles well in the mix.

Thanks again.

*H.A. Hartley's Audio Design Handbook (1958 Gernsback Library), p. 200
**ibid., p. 21

ken mac's picture

for your comment.

Nirodha352's picture

“ and an occasional sheen that revealed the amplifier's class-D heart.‘ please stop trying to give class D amps some high-end validity

rwwear's picture

Sounds like the handles may be the best thing about it?

Ortofan's picture

... tend to resonate, with an adverse effect on sound quality, so they should be removed once the unit is installed.

rwwear's picture

.....Remove the faceplate and knobs, etc....

Anton's picture

"....With a modern direct-coupled solid state amplifier, that initial DC offset will destroy the loudspeakers' woofers."


I'm not kvetching about the sonics or the price, just the risk!

directdriver's picture

According to their website, the preamp's output does not use a cathode follower. Instead it uses a "plate follower" or anode follower which renders it higher output impedance, as shown in the measurements, than typical cathode follower circuits.