Genz-Benz provalve 100 사용자 매뉴얼
- 2 -
BACKGROUND & DESIGN VIEWS
Commentary by B.K. Butler
I wanted to make an improvement over what the market has come to accept as the
standard “Fender-type” power amp design for my new Tube Works model 4250 Tube
Power amp. This old “Fender” design has been around for a long time, and though not
bad, I felt there was significant room for improvement.
My first improvement was the elimination of the troublesome tube phase splitter (or
inverter) which consists of a good number of parts and one (typically) 12AT7 tube per
channel. In addition to this is required and additional preamp tube (usually a 12AX7)
and associated additional high-voltage capacitors and resistors.
As most musicians know, a lot of tube power amp saturation and tonality comes from
the characteristics inherent in the output transformer. However, high power tube amps
suffer from the problem of the fact that they are simply too loud to practically utilize
output transformer saturation characteristics in all but large performance venues. The
only solution (up to now) has been that either the designer provides a low power switch
(one setting which really is not the same as output saturation tonality), or the performer
must use a potentially amp-frying “power attenuator”.
In order to hit several birds with one stone as it were, I mulled over the various design
concepts I could make. I could imagine several designs would solve the typical
problems of over-complexity of the old designs. But my approach also had to fulfill the
need musicians have for variable power output and transfer saturation capability.
My solution is as follows: I employed a proprietary, original design idea in this
amplifier. Each channel has an intermediate high-quality driver transformer which
functions as an amplifier, phase splitter, plus a safe and variable saturation source.
The use of this new design results in the elimination of the tree preamp tubes (and
their related problems with microphonics, matching, aging, noise, loose sockets, etc.),
as well as a number of problem, noise-prone high-voltage coupling capacitors and
resistors. This was not a cost cutting measure. The custom designed and
manufactured driver transformers are anything but cheap! It is however the best over-
all solution to what I felt were the overwhelming shortcomings of most of the tube
power amps available from other sources.
I’m confident that your ears will hear the superior performance mine do from this
amplifier. I can assure you personally that I have put all of my experience and tenacity
into this new design.
standard “Fender-type” power amp design for my new Tube Works model 4250 Tube
Power amp. This old “Fender” design has been around for a long time, and though not
bad, I felt there was significant room for improvement.
My first improvement was the elimination of the troublesome tube phase splitter (or
inverter) which consists of a good number of parts and one (typically) 12AT7 tube per
channel. In addition to this is required and additional preamp tube (usually a 12AX7)
and associated additional high-voltage capacitors and resistors.
As most musicians know, a lot of tube power amp saturation and tonality comes from
the characteristics inherent in the output transformer. However, high power tube amps
suffer from the problem of the fact that they are simply too loud to practically utilize
output transformer saturation characteristics in all but large performance venues. The
only solution (up to now) has been that either the designer provides a low power switch
(one setting which really is not the same as output saturation tonality), or the performer
must use a potentially amp-frying “power attenuator”.
In order to hit several birds with one stone as it were, I mulled over the various design
concepts I could make. I could imagine several designs would solve the typical
problems of over-complexity of the old designs. But my approach also had to fulfill the
need musicians have for variable power output and transfer saturation capability.
My solution is as follows: I employed a proprietary, original design idea in this
amplifier. Each channel has an intermediate high-quality driver transformer which
functions as an amplifier, phase splitter, plus a safe and variable saturation source.
The use of this new design results in the elimination of the tree preamp tubes (and
their related problems with microphonics, matching, aging, noise, loose sockets, etc.),
as well as a number of problem, noise-prone high-voltage coupling capacitors and
resistors. This was not a cost cutting measure. The custom designed and
manufactured driver transformers are anything but cheap! It is however the best over-
all solution to what I felt were the overwhelming shortcomings of most of the tube
power amps available from other sources.
I’m confident that your ears will hear the superior performance mine do from this
amplifier. I can assure you personally that I have put all of my experience and tenacity
into this new design.