Specs & Pricing

Equipment
Report
Joule Electra
VZN-80 MK V
Emerald OTL
Stereo Amplifier
Is it a cult or the real deal
A look at one outputtransformerless
tube amp
Sue Kraft
Lacking the literary prowess of HP, I’m
at a bit of a loss to explain the cult-like
following the output-transformerless
(OTL) amp has garnered over the years. I
suppose it could be compared to a Harley
rider and his bike. If you have to ask what’s so
great about a Harley, you probably shouldn’t
own one. In the case of an OTL, if you have
to ask what’s so special about the simplicity
of an output tube directly coupled to your
speaker, then you just might not appreciate the
utter beauty of it all. Short of actually crawling
inside a tube and becoming the music, you’d
be hard pressed to feel a closer connection
to your system than with a properly designed
OTL amp.
Unfortunately, you have to pay the piper for
such sonic erotica, which probably explains
why you don’t need many fingers to count the
number of OTL manufacturers in existence.
That output transformer, which ultimately
acts as a filter and can’t help but leave its sonic
footprints up and down the signal path, also
serves an important function in the audio
chain. Without it, you’re basically driving a car
with no transmission. Obviously, this is no
problem on a flat open road. But no matter
how much horsepower you put under the
hood, those steep hills and inclines are going
to give you headaches.
78 December 2006 The Absolute Sound
So the rub here is that if you want to do away
with the output transformer and its inherent
negative side effects you have to carefully
match the OTL amp with relatively sensitive
speakers. Otherwise, you’ll be getting bogged
down on the steep musical passages, and the
performance of your system will suffer. Is the
extra effort worth it I’d say emphatically yes,
and point to the Joule Electra VZN-80 MK V
Emerald as one example why.
Retailing at $16k with the optional
Musicwood case and automotive paint finish,
the 80W stereo VZN-80 is the “entry-level”
offering in Joule’s OTL model line. I have
to admit I got off to a bumpy start with this
amp when I had to chase the UPS truck
down the street because I thought the driver
had left a microwave oven on my doorstep
by mistake. Turns out it was no mistake. The
VZN-80 apparently ships from the factory
in a U-Haul microwave box. Knowing how
small most high-end audio manufacturers are,
I rarely complain about less than professional
packaging. But in this case, I feel compelled
to speak out. If we are truly serious about
extolling the virtues of our hobby to the
unwashed masses, how about starting with
a dedicated shipping container that reflects
the quality of what’s inside Besides that, I’m
getting too dang old to be chasing delivery
trucks up and down the block.
U-Haul microwave boxes aside, the VZN-
80 itself looked sharp, with a black acrylic
top and Wineberry automotive finish. I was
surprised by the substantial size of this unit,
as it barely fit on the 19" x 24" Symposium
Svelte shelf I used to keep it off the carpeting.
While the complement of ten driver tubes
came already installed, an octet of 6C33-CB
output tubes and a Variac were packed in a
smaller, separate box. The Variac is housed in
a matching leatherette-covered wooden box
with a large rotary knob mounted on top and
dual captive power cords for attaching to each
channel of the amp. I initially thought both
the amp and Variac had missing bottom plates
but was told they are left open for ventilation
purposes. Basically what you see when you
look underneath are the bare (as in unfinished)
wood frames of the enclosures. A suggestion
might be to paint the underside so it looks a bit
more finished.
Before getting to my listening impressions,
I’d like to note that according to Joule designer
and proprietor Jud Barber, the review sample
VZN-80 is a MK V version, with upgraded,
professionally made circuit boards. Prior
versions all have handmade circuit boards.
Other than looking inside, the only way to
differentiate a MK V iteration is to check