September 2009
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World Premiere!
SoundTradition's Live! MC-10 Moving Coil Step-Up Transformer
An astounding sonic bargain.
Review By Dick Olsher
Click here to e-mail reviewer
It seems to me that a step-up
transformer, at least conceptually, makes the strongest argument for being a
moving-coil cartridge's ideal partner. Let's look for a moment at the required
overall system gain. Assuming a low-gain MC with a nominal output of 0.2
millivolt and a power amplifier sensitivity of 2 Volt, the gain required to
drive the amplifier to full power is no less than a factor of 10,000 or 80 dB.
Most phono preamplifiers are designed to accommodate a MM cartridge and feature
about 50 dB of gain and a 47kOhm input impedance. So we would be searching for
an additional 30 dB or so of clean and low-noise gain. Well, I can't think of a
more logical candidate than a transformer for these tasks. That's not to say
that an active head amp or high-gain phono stage couldn't perform as well, but
the catch would be a much higher price tag. That's the penalty of active
amplification with its dependence on multiple gain stages, expensive passive
parts, and a good power supply which is at the mercy of the AC mains. A
moving-coil step-up by contrast is totally isolated from the electric grid –
it is as passive as they come.
The Live! MC-10 features the Hashimoto HM-3 MC step-up
transformer. Haven't heard of Hashimoto? Well, forget Tamura and Tango, the
Hashimoto brand in my estimation is “best of breed.” Hashimoto Electric Co.,
Ltd, embodies some 60 years of transformer design and manufacturing experience.
Mr. Takao Ishiguro, who is currently a technical advisor for Hashimoto due to
his semi-retirement, has been the heart and soul of the Hashimoto transformer
line for the past 30 years. Prior to that, he had worked at Sansui before they
had transferred the transformer business to Hashimoto. Their stated goal is to
produce the best sounding and highest quality audio transformers and their
products have earned a stellar reputation for sonic excellence. In fact, their
design philosophy focuses not just on excellence in technical measurements but
seeks to capture the inherent beauty and tonal balance of live music. I'm told
that Hashimoto engineers conduct serious listening tests in the context of a
highly-refined reference system to evaluate new transformer designs. These
designs are modified and re-tested in an iterative fashion, until they are able
to reproduce the tonal balance and clarity of the real thing. As you can see,
audio transformer design is more than just about science and engineering, as the
folks at Hashimoto have elevated it to an art form. My recent exposure to the
Air Tight ATM-1S stereo amplifier convinced me of that. The shift from Tamura to
Hashimoto iron in this particular design brought me closer to the essence of the
music.
Technical Details
Although Hashimoto is primarily known for its use
of HiB steel cores, a Permalloy (nickel-iron magnetic alloy) core is used for
the HM-3 as well as all other step-up transformers currently in production. This
is absolutely the right core material for an application that requires high
permeability (ability to carry a magnetic field) and low coercive force. The
core is laminated and cubic in shape, 1.7 cm on a side. Yes, it's tiny exactly
because of the low power levels involved. The core is triple shielded against
electro-magnetic interference (EMI). The core and shields are resin-impregnated
to minimize feedback from physical vibration. A complex proprietary interleaving
of primary and secondary sections is deployed, aimed at reducing leakage
inductance and stray capacitance which constrain a transformer's high-frequency
extension. The HM-3 achieves a wide bandwidth, with -1 dB points of 15 Hz and 50
kHz.
The
primary is split into two sections which can be connected in either parallel or
series via a switch. In parallel connection the gain is x40 and the effective
impedance presented to the cartridge is 3 Ohm, said to be suitable for
cartridges with an internal impedance of 2 to 7 Ohm. While in series connection
the gain is x20 and the effective impedance is 12 Ohms, suitable for cartridges
rated from 7 to 40 Ohm. Since the cartridge has to generate the magnetizing
current for the transformer, this business of matching impedances has less to do
with gain and more to do with maximizing power transfer. However, don't hesitate
to experiment with the load switch. One of the settings should sound best with
your cartridge. The MC-10 can accommodate a wide range of moving coils,
including the popular Denon DL-103 and certainly all of the cartridges I
happened to have in the house.
Isao Asakura, SoundTradition's president places great
importance on chassis selection and proper mounting techniques. He recognizes
that when signal voltage is only a fraction of a millivolt it is prone to
contamination by hum and EMI. Even slight vibrations of the hook up wires can
impact the sound quality. Therefore, he had spent over a year experimenting
with various chassis designs in order to optimize the performance of the HM-3
transformer. The MC-10 uses a 2-mm thick aluminum chassis which is damped to
reduce vibration.
Sonic Impressions
For its grand entrance into the reference system,
the MC-10 replaced the Shelter 411 Type 2 step-up. The Air Tight ATE-2 phono
preamplifier was used for the entire audition period. The MC cartridge in play
at the time was the Dynavector XV-1s, which was in-house for a brief audition.
This is a tremendous cartridge, exceedingly fast, pure, and immediate. And when
the recording permits, it revs up from soft to loud more effortlessly and
linearly than almost any other cartridge out there. The point being that this
was a challenging platform for any step-up, let alone one that in high-end terms
is bargain-basement priced. Well, I'm happy to report that the MC-10 did not
disappoint. It was far from being the weakest link in the chain. In fact,
harmonic color vibrancy increased noticeably. Soprano voice sang sweetly, and in
particular, the upper mids were fleshed out with crystal-like clarity. Retrieval
of low-level detail was a tad better with the Shelter 411, but that finding was
made largely immaterial in view of the MC-10's rare ability to immerse the
listener in the music's emotions. By the way, the XV-1s's internal impedance is
6 Ohm and Dynavector's recommended loading is at least 30 Ohm, but it sounded
best in the 3-Ohm setting.
The MC-10 continued its extended stay in the reference system
while I upgraded my Kuzma Stabi Reference turntable with the Kuzma 313 VTA arm,
which replaced the Graham Engineering 2.5 arm. The Kuzma table/arm combo turned
out fabulous and the MC-10 had no trouble facilitating a rock-solid soundstage
and amazingly palpable image outlines. Fasten your seat belts! Dynamic contrasts
were easily navigated as it shifted “gears” from soft to loud without even a
hint of compression.
Enter the Shelter Harmony MC. I've already sung this cartridge's
praises in an earlier review. Its exceptional coherence and image stability were
undiluted by the MC-10. Yet again I preferred it over Shelter's own 411 Type 2
step-up for its transparency, immediacy, and greater harmonic color saturation.
Tonal balance was full-bodied and wide-bandwidth. An orchestra's bass foundation
was given full scope of expression. Transient attack and decay were very well
controlled resulting in a lucid reproduction of hall decay. In the low-impedance
setting, the sound was almost single-ended-triode like with plenty of kinetic
drive, and lively mids. In particular, there was something very special about
the upper mids, a pure tone that I've come to know and love. And based on my
previous experience with their transformers, it would be fair to describe it as
Hashimoto's calling card. Here too I preferred the low-impedance setting. In the
high-impedance setting, the sound became slightly de-focused and less
dimensional. Textures weren't as smooth and dynamic contrasts were not nearly as
convincing either. Yet the manufacturer's recommended load impedance is 10 to 30
Ohm.
I don't want to leave the impression that the low-impedance
setting was always best. It wasn't. In the case of my long-time workhorse, the
Symphonic Line RG-8 Gold, a modified van den Hul Grasshopper MC, I preferred the
high-impedance setting because of its enhanced dynamics although the treble was
not as smooth. These findings should prove instructive on the importance of
experimenting with the optimum load setting for a given cartridge. The MC-10
gives you a cartridge loading option and it is real easy to flick those switches
from low to high and back again to determine which loading works best the old
fashion way – by letting your ears be the final arbiter when it comes to sound
quality.
Conclusion
An astounding sonic bargain! The Live! MC-10 is a perfect
illustration of the maxim that money can't buy you sonic happiness. You could
spend thousands more and not come close to the MC-10's inherent musicality. It
can hold its own even in the company of ultra high-end analog gear. Warning: you'll
most likely be unable to resist its siren call. For the record, I have
certifiably fallen in love with its superlative sound quality. Highly
recommended!
Specifications
Type: Transformer-based step-up device
MC Cartridge Loading and Gain:
3-Ohm setting (2 -7 Ohm, 32 dB)
12-Ohm setting (7 - 40 Ohm, 26 dB)
Recommended Phono Stage Load Impedance: 47 kOhm
Dimensions: 162 x 158 x 112 (WxLxH in mm)
Weight: 4 lbs.
Price: $990
Company Information
SoundTradition
OBS, Inc.
P.O. Box 616
Lawton, MI 49065
Voice: (269) 978-8690
Fax: (269) 624-6009
E-mail: support@obsinc.us
Website: www.obsinc-products.com