Introduction The
Jolida JD-202A Level 1 Modification amplifier will most certainly
capture the attention of those enthusiasts looking for performance tube
gear that doesn’t require a armored truck delivery of funds to make it
affordable. The modified JD-202A integrated amplifier is the latest
product incarnation from high-end audio veteran Walter Liederman
(co-founder of Hi-Fi Buys). Under his new company moniker “Underwood
HiFi,” (formerly the Grahm Company) Liederman buys the stock JD-202A
and has it modified at the Parts Connexion. This product takes its
place beside other Liederman modified gems from Jolida and Shanling in
the Underwood HiFi line.
The amplifier in question starts life as a standard $750 Jolida
JD-202A, then is shipped to The Parts Connexion, where it is
extensively modified with tubes and components designed to
substantially increase the performance of the product, all without
dramatically increasing the price. The Jolida JD-202A with Level 1 mods
is a 40-watt-per-channel stereo integrated amplifier that measures 12.5
inches wide, 12 inches deep and eight-and-one-quarter inches in height.
The finished unit weighs a modest 28 pounds. The Jolida JD-202A can be
purchased with the Level 1 mods in place for $1,040. Those who already
own the original version can have it modified at the Parts Connexion
for $500. The modified JD-202A has a one-year parts and labor
warrantee, provided by Jolida.
The
modified Jolida JD-202A integrated tube amplifier utilizes two matched
pairs of 6CA7/EL34 power output tubes, 12AX7 tubes in the pre-amplifier
circuit and 12AT7 power driver tubes. The design is retro, with exposed
tubes in front of transformers. There are two knobs and a power switch
on the front panel, one for controlling the volume and the other to
select between the four line level inputs. The back panel features four
pairs of single-ended inputs, four and eight-ohm speaker taps, a fuse
and an IEC power cord outlet. For my most listening tests, I used my
B&K CM4 loudspeakers with the Jolida JD-202A.
Modification After
the base Jolida JD-202A is disassembled, the following changes are
made: Two sheets of Soundcoat chassis damping material are applied. The
stock input driver tubes are replaced with Russian Electro-Harmonix
12AX7 and 12AT7 tubes. Four polypropylene power supply bypass
capacitors are installed. Six Multicap PPFXS signal path polypropylene
film and tin foil capacitors are installed. 24 Riken signal path
resistors are installed. Four Holco H2 non-magnetic, metal film
resistors are installed on the plate of the phase splitter. Four
HEXFRED ultra-fast soft recovery “high voltage” rectifying diodes are
installed in the power supply. One SF4007 Vishay-Telefunken diode is
added to the bias supply. The above modifications all utilize TRT
WonderSolder and take between three and four hours to perform. The Music I
ran the Jolida amplifier for better than a week to allow the
electronics and tubes to break in. I also let the unit warm up for at
least one hour before each listening session. For best performance, I
strongly recommend that you let this and any other tube gear warm up
before any serious listening session.
For starters, I
reached for a disc that I hadn’t heard for quite a while, For Duke by
Bill Berry and His Ellington All-Stars (Real Time). This well recorded
album features a small jazz band in an intimate setting. While
listening to “Take The A Train,” I noted that the horns had huge body
and presence and the highs were open and not shrill, all signs of
quality tube electronics. The sound was relaxed and tonally balanced.
The soundstage appeared small and intimate, making me feel as if the
band was about 10 or 15 feet away and the instruments were well placed
in the soundfield. The “Perdido” track featured bass notes reproduced
with authority at moderate levels, without any bloated, blubbery notes
associated with lesser-performing tube equipment. The saxophone in this
track was very realistic and engaging. On the “Birdland” track, the
tuba playback demonstrated a lot of weight and detail for such a
modestly powered amplifier. This song is paced fairly quickly and the
Jolida had no problems averting congestion. The sound was very liquid
through the midrange, demonstrating the tube’s reputation for truly
palpable midrange frequencies. As with most tube gear, I felt at times
that the highs tend to be slightly rolled off, giving the music a
relaxed feel. This, however, is not atypical for most of the tube
equipment that I have auditioned. Let’s face it, you don’t buy tubes
for lightning-fast transients and rock solid accuracy, you do so for
their uniquely seductive presentation.
Next,
I moved on to a larger-scale performance, Tchaikovsky’s 1812 Overture,
featuring Eric Kunzel conducting the Cincinnati Symphony Orchestra
(Telarc). The little Jolida portrayed a much larger soundstage than I
expected. I did feel that the modified Jolida became slightly
compressed when it was driven to higher volumes and its ability to
resolve details could become slightly degraded, yet this is very
typical of any electronics driven to levels beyond their normal working
range. What this tells me is that the amplifier should definitely be
paired with a pair of efficient loudspeakers for optimum performance.
Interestingly, though, the sound remained consistently sweet through
the midrange, even when the amp became strained. I then listened to
Eric Clapton’s Slowhand release (Mobile Fidelity). The track “Wonderful
Tonight” had Clapton’s voice floating about 10 feet in front of me. His
voice was solidly anchored and very accurately reproduced. The guitar
was reproduced with very palpable warmth and detail. I enjoyed this
recording very much through the Jolida amplifier.
I
then gave the Jolida Level 1 mod amplifier a real workout with Janet
Jackson’s The Velvet Rope (Virgin Records). The relaxed sound
encouraged me to crank it up to get that “in your face” sensation. The
Jolida never became forward or harsh at any volume. When evaluating
low-frequency performance in the track “Go Deep,” the cut had less
impact and weight in the bass than the Parasound Halo combo that I
reviewed a few months back, but maintained admirable detail and
displayed infectious sweetness.
Yearning
for some real hair-band music, I reached for Van Halen’s debut release
(Warner Brothers), which perfectly filled the bill. This was the only
recording that didn’t tickle my fancy when played through the Jolida
amplifier. I found it to be a little too relaxed for stadium rock the
way I like to hear it. When I listen to hard-driving music like Van
Halen, I want it to have that edge that gets you rocking. The Jolida
amplifier simply didn’t have the spunk to get this done. While
listening to “Runnin’ With the Devil,” the electric guitar had no edge
at any volume. This was the only album where I felt the laid-back
presentation detracted from the music.
I then listened to
some more jazz and blues to see how they held up after my rock ‘n’ roll
experience. I put in the audiophile cliché Arne Domnerus’ Jazz at the
Pawnshop (Prophone, Gold Edition) and immediately noticed that the size
of the soundfield was well suited to the music. On “Jeep’s Blues,” the
applause at the track’s opening sounded like it was in the room with me
or, better yet, like I was in the room with the crowd. Single handclaps
had that bone and flesh resolution that let me focus on individuals in
the crowd. In many cases, I find that gear can provide exceptional
crowd detail, but it is rare when the physical sound of an individual
clap sounds so natural that it fools you into believing that it’s in
your room. On “Take Five,” the upbeat pace of the horns and drums was
recreated with a good sense of timing and rhythm, while the music was
cohesive and presented well. Instruments sounded realistic both in size
and texture, and had a very naturally-voiced timbre.
The
last piece of music was from Mighty Sam McClain’s Give It Up To Love
(XRCD). Again, the Jolida amplifier presented an accurate sense of
space. The Hammond organ on “What Do You Want Me To Do” was smooth yet
strong, with a very full sound. At moderate listening levels, the fiery
vocals, guitar and strong drums were reproduced with no congestion and
good overall balance. The strong, clear midrange served the vocals and
music quite well. Overall, the modified Jolida amplifier performed like
a tube amplifier, which would have a much higher price tag than the
moderate-cost Jolida does. Tube amplifiers are a delicacy appreciated
by the purist with a flair for midrange reality. The Jolida amplifier
supplied a delectably palpable midband that is sure to put goosebumps
up the spine of any vocals enthusiast.