| Budget-Amp Mini Trilogy |
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Tubes vs. Solid-State With a Side Dish of
Digital! |
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Frank Alles
April 2004
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Prepare yourselves for an epic battle,
performed by adept challengers from different
disciplines. In one corner we have the Sophia Electric
Baby, a 10 Wpc, push-pull, tube design, and in the
opposing corner, the Monarchy Audio SM-70 Pro, a
solid-state, class-A MOSFET combatant that uses no
negative feedback. Both amplifiers are close to the
same price point, with the Baby weighing in at $799
and the Monarchy at $980. And attempting to dethrone
both of our prospects is the Panasonic SA-XR45
receiver, an unlikely entrant from the all-digital
dojo.
The Monarchy SM-70 Pro is more powerful than the Baby,
putting out about 35 watts per channel into 8-ohm
loads, or 80 watts in mono. I used the very efficient
(101 dB/W) Klipsch Chorus speakers to even the playing
field for the 10 Wpc Baby. We shall see how well our
warriors joust in the following head-to-head
encounter. Don your helmets and Oakley’s ladies—this
could get messy!
That’s My Baby!
First off, I have to say that the Sophia Baby is a
very stylish and appealing little amp. It can be
bought with cosmetic enhancements as well as speaker
post and capacitor upgrades. My unit is their basic
model with the cherry-wood front fascia. It also has
the advantage of a handsome gold front panel volume
control, allowing a single source component to be
plugged directly into its inputs without the need for
a preamplifier.
Playing through many of my test CDs, the Sophia Baby
displayed some regal traits exceptionally well. It’s
linearity and freedom from the usual cliché tube
colorations was a welcome surprise. The Baby sounds
very natural on all types of acoustic instruments and
its transient speed is truly first rate. I recall
listening to a recording with a solo violin being
played fast and furiously. With lesser amps hearing
the violin can be a painful experience, with the
instrument sounding blurred and screechy. But the Baby
was able to reproduce the nimble bowing with all its
micro-changes in pitch and volume while at the same
time managing to sound like a real violin. I was
impressed. Plus, it’s a very smooth and liquid
sounding amplifier, which was not a big surprise,
considering its tube topology.
The Baby’s bass articulation is very good. Runs on
acoustic bass, the bowing of the cello, and the lower
registers of the piano sound quite natural and
seamless. That said, the Baby is not as solid and
extended in the deep bass as the Monarchy SM-70 Pro.
But, for me, the shortfall of the Baby was its
tendency to sound strained and compressed when asked
to play moderately loud. In my large 14’x30’ listening
room I sometimes felt the need for just a dB or two
more than the Baby could comfortably provide. I have
heard comments from other audiophiles that the Baby
can comfortably power speakers of about 90 dB/W or
greater efficiency, but I suppose they like to listen
at lower levels than I do or have smaller rooms.
However, when used within its power limits, the Baby
is a very excellent amplifier. In fact, when playing
Diane Schuur’s vocal on “The Christmas Song” from A
GRP Christmas Collection [GRP GRD-9574], I was taken
aback by the Baby’s vivid, lifelike rendering. It was
literally the best I have ever heard this recording
sound.
Enter the Dragon
When I first installed the SM-70 Pro in my Klipsch
system, there was an unusual occurrence. I began my
listening with Shaggy’s Hotshot CD [MCA 888 112 096-2]
and noticed that the lyrics seemed much harder to
understand than they were when using the Baby. Indeed,
my wife commented from the next room that the singer
sounded like he had marbles in his mouth. Hotshot is a
good test for lyric intelligibility because Shaggy
sings/speaks the words so fast that they are difficult
to catch unless everything in your system is working
very well.
At any rate, I had just received another pair of
Analog Two interconnects from SignalCable and I
decided to replace Gary Markowitz’s Remarkable cables
with those. After inserting the Analog Twos between my
preamp and the SM-70, an interesting thing happened.
Replaying the Shaggy cuts that had previously sounded
muddled, Shaggy’s voice was now more “human” sounding,
and much easier to understand. It appeared that the
Baby still held a slight advantage in terms of
ultimate speed and lyric comprehension, but now the
two amps were comparable, and the difference was
slight. Curiously, reinstalling the Baby amp and
trying it with the SignalCable interconnects did not
appear to make it sound any better than it had with
the Remarkable cables.
In using the Monarchy SM-70 Pro I discovered that the
hum and noise from the amp was somewhat of an issue
with the 101 dB efficient Klipsch. By contrast, the
Baby was VERY quiet. But with the Monarchy, I could
hear the hum from my listening seat when all was quiet
and found it a little distracting. At that point I
contacted Monarchy’s C.C. Poon to find out if the
input circuit of the SM-70 Pro could be adjusted for
less gain, and hopefully, less noise. Mr. Poon assured
me that this could be easily accomplished by changing
the value of two resistors in the input stage and
agreed to perform the modification on a second sample.
Dragon Slayer?
Then, one day, whilst perusing the for-sale ads on
Audiogon.com, I chanced to spy an unusual ad from John
Meyer of Newform Research. It proclaimeth that the
Newform R645 speakers will sound oh-so-delightful,
when bi-amped using the Panasonic SA-XR45 all-digital
receiver. John explaineth how the Wizards of Panasonic
went to the Thaumaturgists of Texas Instruments to
consult and conspire on the arcane art of 1’s and 0’s.
Subsequently, they developed an advanced digital
receiver that could be sold for the price of topsoil.
Could it be?
I figured that no self-respecting audioknave could
pass up an opportunity, nay, a challenge, like that,
so for all of $300 (best price I found on the
Internet) I was determined to find out for myself.
First, let me make it clear that the Panasonic SA-XR45
is a Dolby-Digital, 6-channel receiver, not a basic
stereo amplifier. But audiophiles have found that it
performs very well when used as a stereo amplifier via
its direct digital input, or with an analog source via
its direct, 6-channel analog inputs. Another simple
modification that I adopted was the use of an
inexpensive IEC adapter, which allowed me to use a
higher quality power cord.
After installing the Panasonic in my system and
letting it burn in for a couple of days, I sent the
following brief assessment to a friend of mine:
I have bloom, I have presence, I certainly have
dynamics and extremely clear, full-range sound. The
bass is rock-solid and very articulate and natural.
The clarity and detail may be better than any of my
other amps. Guitar strings, cello, piano, and
woodwinds sound very convincing and brasses sound very
good, although I have heard better. Vocal reproduction
is very competent and surely above average, while
lyric comprehension is strictly first rate. There may
be a slight coloration in the highs, but it is not too
distracting.
While my initial impression of the XR45 was very
positive, I had overlooked certain quirks in its
performance that started to bother me over time. For
some reason, it just didn’t sound totally convincing
when reproducing brass instruments, and although the
high frequencies were rendered very well, something
about the treble was not quite spot on—but it was
close.
Return of the Dragon
I’ll admit it, I was actually very pleased with the
Panasonic XR45 in my system and I was definitely
enjoying its remote control, which gave me volume,
channel selection, and muting capability from my
listening seat. I could even play its AM/FM tuner and
switch the stations. Ha! What more could I possibly
want?
Then, as fate would have it, one day upon my return
from work I noticed a familiar white box with blue
lettering lying on my foyer floor.
The very next day, I unboxed the updated Monarchy
SM-70 Pro and reluctantly put it back in my system. I
didn’t expect it to sound much (if at all) better than
the XR45, and I had gotten rather used to that
beguiling remote control. Arrrrgghh!
Then, upon firing it up and hearing the splendor and
magnificence of its sound, my feelings of reluctance
faded. I began enjoying a musical feast fit for a
king—or at least, an audioknave. Best of all, with the
input gain modification, this SM-70 Pro was quiet.
Yes, one could hear a bit of hiss with one’s ear right
up to the speaker, but it was not audible a few feet
away, and the hum was totally banished.
NOTE: This is the latest,
much-improved version of the SM-70 Pro amplifier and
the details of the changes are outlined following this
review. As a courtesy to present SM-70 owners,
Monarchy’s C.C. Poon has agreed to perform the input
modification to any version free if the owner agrees
to pay the full shipping charges to and from Monarchy
audio. This offer is only for installation of the
input gain resistors and does not include any other
upgrades or modifications to the amplifier.
What clobbered me over the head was listening to
Alicia Keys’ Songs In A Minor [J-Records JB 20002].
Her vocal pierced my tympanic membrane right through
to my heart, which gave rise to the fabled gooseflesh.
And her nimble fingers on the ivories struck chords so
natural and pure that I sat transfixed and was
transported to a place we seldom reach in our myriad
audio journeys. That’s when I knew the Dragon had
returned.
I had previously listened to the aforementioned Alicia
Keys CD on the XR45 and it did not provide the same
transparent, soul-reaching experience. The bass and
dynamics were there in full force, as was the clarity,
but the harmonic rightness of the midrange and treble
was not up to the high standard of the Monarchy’s
performance. Instead of being drawn in to the
experience, I was somewhat put off by it.
Playing several selections from the Squirrel Nut
Zippers’ Hot [Mammoth 354 980 0137-2] confirmed my
impression that the Panasonic could not get the
brasses quite right. Here the Monarchy amp ruled, and
managed to sound musical and captivating while doing
so. The timber of the various brass horns was much
more natural through the SM 70 Pro.
Happily Ever After…
The moral of this story is that we have three glorious
competitors, each with their own special set of
strengths and failings.
To sum up, the Sophia Baby in my estimation is the
most natural and musical of the trio, but is lacking
in headroom and bass extension/solidity. Also, it
tends to sound harsh when pushed. Yet the Baby is hard
to beat when paired with high efficiency speakers
played at low to moderate levels. It would likely
sound great driving the midrange and tweeters in a
high-efficiency, bi-amped system, as well.
The Monarchy SM-70 Pro is very nearly the Baby’s equal
in terms of timbre and musical truth, but it can play
much louder without strain and is more authoritative
in the low bass. Of the three amps, it is my personal
hero. A pair of SM-70s can be used as bridged
monoblocks in installations where higher power is
needed.
I was VERY impressed with our lowest-cost, digital
competitor from Panasonic. The SA-XR45 lacks the
immediacy and harmonic rightness of the Baby and the
SM-70 Pro, but it acquits itself admirably in terms of
bass extension and articulation, dynamic capability,
and clarity (freedom from congestion with complex
material). It runs cool, is energy efficient, and has
remote control. Putting out 100 watts per channel into
6 ohms, the SA-XR45 is the most powerful amp in this
group. Wayne Waananen of the Bolder Cable Company
(famous for his ART D/IO D/A converter mods) offers a
modification package for $700 that reportedly improves
the performance dramatically.
Following are the specifications and company
information, and finally, my Associated Equipment list
for this review. Happy listening!
Sophia Electric, Inc.
Washington, DC
Voice: (703) 204-1429
Fax: (703) 560-3502
E-mail:
sales@sopohiaelectric.com
Website:
www.sophiaelectric.com
Baby Specs:
Power: 10 watts x 2 Push and Pull class A circuit
Input: One set of RCA input
Output: Russian Military 6P1T x 4 (with special
treatment for low noise)
Input/Driver tube: NOS 5670 (USA)
Frequency: 6Hz-80KHz +/-3 dB
or 10Hz - 50KHz +/-2 dB
12Hz - 45KHz at 0 dB
Signal/Noise Ratio: -95dB
Distortion: less than 1% at full power
Hum: not measurable (less than 0.3mV)
Weight: 20 pounds
Size: 7 inch x 9 inch x 5 inch
Price: $799.00 to $899.00 depending on options.
Monarchy Audio
380 Swift Ave., #21
S. San Francisco, CA 94080
Voice: 650-873-3055
Fax: 650-588-0335
Email:
monarchy@earthlink.net
Website:
www.monarchyaudio.com
SM-70 Pro
Weight: 25 lbs.
Price: $980
Recent Upgrades:
1: Epoxy-filled toroidal transformer (for lower noise)
2: Higher Power Output MOSFETS (old version: each
MOSFET 7 amps/160Volts)
(New version: each MOSFET 8 amps/200Volts)
3: Easier Service: The MOSFETS are mounted on aluminum
strips; on old
version they were mounted on the chassis.
4: Lower Input impedance: 70K instead of 100K to match
preamps better.
5: All WIMA audiophile grade caps in signal paths for
better sound quality.
6: Laser Engraved rear panel for better cosmetics and
identification.
7: Some refinements on Component values
8: 50 Volt Electrolytics (older version 35 Volt) at
filtering
9: Heavier top and rear panels (for more sturdy look
and feel)
10: Improved construction techniques.
Panasonic Consumer Affairs
Panazip 2F-3
One Panasonic Way
Secaucus, NJ 07094
Phone: 800-211-PANA (7262)
Website:
http://www.panasonic.com/consumer_electronics/home/flash.asp
Panasonic SA-XR45
Power Output
Home Theater Mode --
Front: 100W/Ch x 2 (1 kHz, 6 ohms, 0.9% THD)
Center: 100W (1 kHz, 6 ohms, 0.9% THD)
Surround (Left Surround, Right Surround): 100W/Ch x 2
(1 kHz, 6 ohms, 0.9% THD)
Surround Back: 100W (1 kHz, 6 ohms, 0.9% THD)
Stereo Mode -- 100W/Ch x 2 (10Hz-20kHz, 6 ohms, 0.9%
THD)
Frequency Response 10Hz-44kHz, &plusm;3dB
S/N (IHF A)
Digital Input -- 98dB (IHF '66)
Load Impedance 6-8 ohms
Frequency Range
FM Tuner -- 87.9-107.9 MHz
AM Tuner -- 530-1710 kHz
Universal Remote Control
Weight 9.2 lbs.
Dimensions (H x W x D)
2-29/32" x 16-15/16" x 14-3/4"
MSRP: $499.00
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