|
The Scrambler Building the long discontinued sought after Ampeg© Scrambler last update: May 14, 2010 Copyright
2010-25
by H.
Gragger. All Rights Reserved. All information
provided herein is
destined for educational and D.I.Y. purposes only.
Commercial re-sale,
distribution or usage of artwork without explicit
written permission of
the author is strictly prohibited.The original
units with
their
associated trade-names are subject to the
copyright
of the individual copyright owner. The Author is
by no means affiliated
with any of those companies. References to trade
names are made for
educational purposes only.By reading the
information provided here you
agree to the Terms
of
Use. The working language
is kept in English as an aid. Read here
why.
|
| MAIN PAGE>MUSIC
STUFF>SCRAMBLER Index  Building ExperienceSound SamplesBuilding Experience This unit is
not subject
to modding - at least not in the author´s
experience. It is beautifully
weird as is.
I used the tonepad layout, what they call the Revolcador. This is a bit crammed for my taste, but at least there is provision made for evaluating diverse transistors on the PCB. Also, most caps are electrolytics, which very often use the same footprint for various working voltages, unlike film caps. So most of the caps that rumble around your drawer will fit. Before I realized that I had already ordered a set of MPSA14, I made homebrew piggy-back darlingtons out of garden variety silicon transistors which worked fine. In fact, they sounded a little sweeter than the MPSA14, but I did not use them after all in because they were a bit bulky in the crammed layout. If I were to rebuild the board, I would use the board mictester had done for this very purpose. One thing I noticed, when I was sweeping the balance knob (which is a mixer between dry and effect), the volume dropped somewhat towards clean - meaning I have too much gain. This is contrary to what somebody else has experienced, who had too little gain. This must be subject to the transistors used. Fortunately, this is very easy to remedy. One could modify the collector resistor of Q4 in analogy to the method shown by the previously mentioned builder. But dropping the value of this resistor may change things in an unwanted way besides increasing the current draw slightly. I decided to leave the overall value intact but splitting the collector load and tapping the output signal from the split point instead. It turned out, that a half/half split works fine (470 Ohms). The balance control now sweeps smoothly from clean to distorted. I think it is clear what I have done, so there is no need for a schematic. Back To Index Sound Samples
I did not make
any sound
samples because there are plenty of them around
and mine does not sound any different . Also,
there there is no
tweaking.
Back To Index Update History
MAIN PAGE>MUSIC STUFF>SCRAMBLER |
MAIN PAGE
| MUSIC STUFF | IMPRESSUM  (c) 2010-25 AQUATAUR Musik & Elektronik |
