Jaton Operetta A2300AX Stereo Power Amplifier
A glorious combination of warmth yet with a good dose of neutrality too.
Review By A. Colin Flood
We know that
most loudspeakers require an enormous amount of energy. No, make that most music
requires an enormous amount of energy. No, make that most loudspeakers require
an enormous amount of energy to make music. An audiophile quality loudspeaker,
with a fairly typical 85dB/W/m efficiency, may require less than a watt to
reproduce conversational sound pressure levels (SPL) about 10 feet away, yet for
brief microseconds musical peaks 30dB higher at full volume can require as much
Tweaking audiophiles deal with this problem three
1. Play music at moderate levels. I recently
heard a complete Quad system. The sound of its music could make Julie Andrews
jealous. But the system couldnít replicate rock concert SPLs cleanly; it
canít party like a PA.
2. Use uber-efficient loudspeakers, like my Big
Ole Horns (see Reviewerís Bio*). These 104dB/W/m behemoths require only 60
watts to play 40dB peaks!
3. Use outrageous wattage monster amplifiers like
the Boulder 3050
Founded in 1983 in Taiwan, Jaton ('je,ton)
relocated to San Francisco in 1988. Their system has a Operetta RC2000P
pre-amplifier and REAL A3 loudspeaker (review coming). In a fashion, their new
system attempts to resolve the power problem of music reproduction all three
1. It doesnít try to be the
loudest system possible
2. The A3 loudspeaker is more efficient than average, with 89dB/W/m efficiency.
3. So with 300 Watts into 4 Ohms, their A2300AX amplifier can cleanly power their A3 loudspeakers to 100dB musical peaks
The Class A designation for amplifiers means that 100% of the
input signal is used all the time. The active elements remain conducting. There
is no quick microsecond switching off and on. Class A amplifiers are typically
more linear and less complex than other types, but are very energy inefficient.
They are clean sounding, but consume electricity.
George Cheng, Product Manager, answered my questions. He says
the model name means AP, for amplifier; the 2300 designation means two channel
with a total of 300 watts at 8 Ohms. The AX appellation means it is analog
design with XLR input. Cheng says the design concept of the Operetta amplifier
is to push the highest gain out of the parts and circuit design, in the same
time, eliminate the most noise and modulation distortion. "In generally,"
he says, "you don't need a very active signal in order to get the detail and
richness with Operetta amplifiers compare to other amplifiers."
There isnít an iPod and PC analog input, there is no space
for it, but a passive pre-amp will work well. The Operetta amplifier is stable
with 4 Ohm loads. Cheng does recommend 20 Ampere electrical service. The
amplifier needs air space around it (tube amplifiers require about two feet on
all sides for proper air circulation). It did get a mite warm, but never hot. In
fact, I eventually placed my bass amplifier on top of it and never worried about
the Operetta getting hot. The stereo channels cannot be strapped together to
provide even more power. Cheng said "the two-stage design can maintain the
warmest of Class A design and also prevents the generating of heat. First the
voltage IC stage and then the current Darlington stage." The Operetta amplifier
has a fan so quiet I never noticed it was on. It automatically turns on when
temperature heats up. There is an output relay which will shut-off the amplifier
to protect it and the loudspeaker. Unfortunately, their control unit won't
shut-off or put the power amplifier into stand-by mode.
He said "It took us a long time to find the balance of these
two stages design. Sometimes it generates too much of the heat and even burn the
Darlington out and sometimes it doesnít have enough power output. Especially
the feedback circle of Darlington stage really caused a lot of time and effort
to final its definition." Jaton loves Mundorf components as they are using six
of Mundorf capacitors just for the two feedback circle to make the Darlington
stage powerful yet operate cool after playing for days. Jaton took nearly two
years to achieve their goal and find the balance of two stage amplifications and
define its circle too.
The front panel has a shining blue power indicator, to remind
you of who is providing the musical pleasure. The speaker cable binding posts
are on opposite corners of the amplifier, which provides room to attach my thick
Coincident rattlesnakes, but the posts are covered with a clear plastic shield.
The shield makes attaching a loudspeaker cable tricky, but once connected, it
helps to hold the cable in place. Cheng did not know why these posts were used.
To turn on this 80-pound black block of power, you have to reach across its top
and down between the input cords. The power switch is located on the back. There
is a tiny yellow circuit breaker next to the flip switch. It is easy to hit that
button by mistake. Of course, this is no biggie if you use a line conditioner to
switch your components on. Jaton fills orders in three to five working days.
There are some retail stores in the States selling Jaton products. Shipping is
usually by FedEx Ground unless there is a bundle shipment by trucking.
Nothing I threw at it was out of the Operetta's
league. I listen to a variety of music, including choir, as part of my "Test
Discs: Reference Recordings for Subjective and Analytical Comparisons." But the
closest reference country and bluegrass music is Holly Cole and Allison Krause
(with Robert Plant)*. The Operetta easily handled everything thrown at it no
matter which loudspeaker used.
(10 Hz - 60 Hz)
When I did flip the power switch, without hitting
the little yellow breaker, the Operetta always had plenty of power. Whenever I
see 150 Watts into 8 Ohms doubling into 300 Watts into 4 Ohms, which the
Operetta does, I think bass control. This spec makes me think the amplifier can
push the woofer, not the other way around.
(80 Hz - 200 Hz)
I did not have The
Matrix and X-Men movies or the Nelson Pass X250* to compare, but nothing
budged the Operetta. There wasnít a feeling of oodles of reserve power, as
there was with the X250 on my Big Ole Horns. Instead it was more of a calm and
quiet "I can handle this" aplomb.
In fact, the Operetta bass was authoritative, detailed,
solid and effortless. The woofer control made for taut, accurate bass not
exaggeratedly fast or numbingly slow. It was not or flabby, boomy or bouncy. The
X250 had hard bass, but not with the clinical edge of typical solid-state
amplifiers. I donít think the Operetta is as hard, but I never thought it had
that solid-state harshness either.
(200 Hz - 3,000 Hz)
The Operettaís unassuming looks reflect its
sound. My audio club acknowledged the generally neutral sound of the Jaton
pre-amplifier*. The amplifier is the same even-handed balance. However, the
combination of the two was not magical. Call me a tubie. As it has so many times
before, Diana Krall's Stepping Out*,
still part of my reference stack, continued to send me into clouds of alpha
state. The flute test on DMP does DSD
passed with flying colors. The Operetta sound is not dry. Even saxophones
sounded wonderfully natural. They did not have the blare of the bell, but they
did have rasp of the reed. The Operetta did not bang drums as hard as I remember
the X250 did, but they knocked and thumped.
(3,000 Hz on up)
It doesnít seem fair to describe the sound of
one super-amplifier as different than another. Its like sitting on a South Beach
bench splitting hairs between the Lamborghinis and Ferraris idling by; to the
casual observer, there is nary a paycheck of difference between them. Yet, I
would generalize the X250 treble as more of a cowbell clang than the triangle
ring of the Operetta. Both are pleasing. Attack seemed a bit slower than tube
amplifiers, but in other respects, The Operetta was above average. Solid-state
amplifiers can hold a note. Again, memory gives the edge to the X250. But if you
are considering Jatonís A3 speakers, I donít think this edge is enough to
consider the X250 over the Operetta. As you will see in my upcoming review, the
Operetta and A3 combination works great together.
All the music had range and extension. Multiple
instruments played as if each had their own speaker and amplifiers. The Operetta
did not mash the chorus together. There was no lack of resources for musicians
to draw upon.
When I paired the Operetta with my tube
pre-amplifier, a world of wonderful music opened up for me. On either the single
driver Supravox Carla towers* or their A3 loudspeakers, the tube and solid-state
partnership created engaging, enticing enjoyment of the music. I didnít think
there was anything wrong with anything about the Operetta - there is that
neutral word again - but when I swapped my Dynaco pre-amplifier into the chain,
there was everything right. The figures came out of the mist, I could see the
whites of their eyes; the 3D holograph was intact.
There isnít major item to anything to note
about the Operetta. Itís a big, heavy black box with a bright sapphire eye and
shielded speaker cable binding posts in its corners. One little thing though,
the power switch is tricky to reach. It is on the rear, between the input cords.
I did not notice a need for a warm-up time,
but then my equipment usually stays on all weekend. I never heard the internal
fan running from across the room. Only when I was over the Operetta, trying to
reach that infernal power switch did I notice the soft burr of the fan.
For The Money
The only real objection I have to the Operetta
was price. It has a lot of competition and its price is a far-flung orbit from
my down-to-earth budget. With my tube preamplifier, the combination had the warm
and lush midrange that tubophiles revere. Vocals with the Operetta were clear
and neutral. In this respect, as well as everything else it did on these
subjective tests, it is a reference grade amplifier in almost every regard. It
has the power to stand aside and not be heard. Imaging extended to the 3D
dimension that tubes do so well.
Summing It All Up
sum it all up, a super-amplifier is overkill for Big Ole Horns yet it seems to
be a near perfect and practical match for the Jaton A3 loudspeakers. Together
they managed to do almost everything well. If you play music at moderate levels
and/or above-average efficiency loudspeakers, if an outrageous wattage monster
amplifier is not an option then Jatonís A2300AX stereo power amplifier with
300 Class A watts at 4 Ohms should make just about any tweaking audiophile
Type: Solid-state stereo power amplifier
Power: 300 Watts @ 4 Ohm, 150 Watts @ 8 Ohm, 2 Channel
THD + N %: < 0.01% @ 8 Ohm, 1 kHz, 150 Watts
Frequency Response: 16 Hz to 40 kHz (+/- 3dB)
Max Output Level: 49 V
Max Gain: 30 dB
Max Power Consumption: 1650 VA
Input Impedance: 20 kOhms RCA, 300 Ohm XLR
Input Connection: 2 of Unbalanced RCA, 2 of Balanced XLR
Output Impedance: 4, 6, 8 and 16 Ohm
Output Connection: 2 Pairs of 5 Way Binding Posts
Dimensions: 17 x 7.5 x 15 (WxHxD in inches)
Weight: 80 Lbs.
Jaton Corporation USA (Headquarters)
47677 Lakeview Blvd.
Fremont, CA 94538
Voice: (510) 933-8888
Fax: (510) 933-8889