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Guitar Rez Product of the Month For September!
The PRS HG-70 Harmonic Generator Guitar Amplifier
Head and Matching 4x12" Cab
This great-sounding half-stack is a fine example
of one of the coolest guitar amps you've probably never heard of
--the PRS HG-70 Harmonic Generator! And yes, you read that
right---PRS, as in Paul Reed Smith, builder of some of America's
most highly acclaimed and best-loved electric guitars over the last
20 years. In the late 1980's, vacuum tubes used in guitar amps
became scarce as more and more tube manufacturers ceased
production. Smith set out to design a top-flight guitar amp using
transistor technology, and the PRS HG-70 Harmonic Generator
was the result, without doubt one of the sweetest, warmest solid-
state guitar amps ever made.
The Harmonic Generator's circuitry was designed primarily by Eric
Pritchard, currently of Pritchard Amps, and was innovative in two
key ways. First was the use of a harmonic generator (surprise!)
that was used to add additional harmonics to the amp's basic tone
to create a lively, more tube-like sound and response to playing
touch. Secondly, the PRS HG-70 was one of the very few
transformer output-coupled transistor amps ever designed. In essence,
it actually utilizes an output transformer, much like a tube amp.
The PRS HG-70 sports two channels. "Rhythm" produces fat, rich
sounding clean tones, while "Solo" yields overdriven crunch and
lead tones. While the Solo channel is ideal for punchy blues leads
and fat classic rock riffing, it stops short of delivering over-the-
top, max-gain metal or thrash tones. The HG-70 is definitely
geared more toward lush, vintage-flavoured clean and overdrive
sounds. Not to be left out is the Harmonic Generator's handsome
matching cabinet, unusually small for a 4x12" speaker cab.
Warren Haynes of Gov't Mule used one of these cabs with his Soldano
amps for many years, and it is a fine-sounding box that
complements the HG-70's tones nicely.
So what went wrong? Why haven't you heard of the PRS HG-70
Harmonic Generator amp until now? When the amp made its debut
at the 1991 Winter NAMM Show, it sported an unusually high list
price for a solid-state amp, due mostly to the extensive R&D that
went into the design, as well as the expense of its high quality
components. In addition, the U.S. commenced the bombing of Iraq
that signaled the start of Desert Storm just as the 1991 Winter
NAMM show got underway. This led to a conservative, slow
sales year for the music industry that created a climate unfriendly
to a new and untested high-end product like the HG-70.
The real killing blow, however, was the fall of the Iron Curtain in
Eastern Europe, which led to an explosion of vacuum tube
manufacturing in Russia and the former Communist Bloc. The tube-free
future that PRS envisioned never materialized, and as innovative
young companies like Rivera, Bogner, Soldano, and many others
created a Renaissance of innovative tube amp design, the HG-70
was left without anaudience. Only about 350 heads and combos
were shipped beforeproduction ceased.
This is truly a terrific sounding amp, and an ultra-rare, hard-
to-find gem. This specimen is in outstanding condition. Although
listed as a "used" item, our HG-70 head has never been sold, and
is therefore technically a new amp! However, it has been out of
production for so long that the factory warranty can no longer be
honored. Condition is excellent with the exception of a little dust
and some minor shop wear. The cabinet is a one-owner used
model that we originally sold. That owner had us install a stereo/
mono switch similar to that used on many modern Marshall
Don't miss your chance to own a unique piece of PRS history!