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Re: Model 391/12

Posted: Tue Sep 09, 2008 4:17 pm
by scotty
As usual youve been most helpful Peter thanks again!

Here is a section of the post form Mark T..




By the way, there are 17 controls, not 13 as
previously mentioned. (think I'm cross eyed ?
read on....)

The top three switches (ones nearest the bridge)
control a Vox Treble Booster, a CEI-ACT-1 compressor,
and a Jordan Signal Booster.
All of these devices were made in the 60's and
were scrounged up back then.

The three round knobs in the center area of
the pick guard are 4, 5, and 6 position rotary
switches which dial in various amounts and types
of filtering on the inputs or outputs of the
various devices. (for instance, the 6 position
switch has a position for a direct connection
between the pickups and the output in the
first position, and the second position has
the good old .0047 mfd. capacitor like the
older 60's RIC guitars had installed in them.
I can take the tone way beyond that, and it
makes some wild sounds - kinda like a thundering
harpsichord... The three bottom switches are
the pickup selectors - which are three position
toggles. The guitar is wired for full stereo,
so I wired the switches such that you can make
any pickup go to any channel in any combination.
(except both channels at the same time which
is not desireable in this case) The remaining
two toggle switches are for stereo/mono which
also takes the non-effects or "cold" channel
and runs it through the Jordan before mixing
back into the "hot" or effects channel prior
to leaving the guitar. The other toggle takes
the signal from the pickup selector switches
and runs it directly out of the guitar without
any coloration by the volume or tone pots at all.
I have used this before for studio stuff, and
incorporated it here again. The three knob
cluster which looks like it might be pickup
volume / tone controls are not that exactly...
First of all if you look close, you will notice
that there aren't just 3, but actually 6 controls
arranged as an inner and outer control. The upper
pair are: inner: hot channel or hot channel +
treble boost output level and outer: is
the "cold" or non-effects level. The rear-most
pair are: inner: Jordan output level, and outer:
cold channel tone control. Lastly is the pair
on the outer bout of the treble side - the
inner is the compressor "clamp" (which works
to limit the "pumping" and feedback problems with
this compressor, the the outer control is the
compressor output level. The guitar is powered
by a 10 volt power supply which comes up one
of the 4 wires in the guitar cord. I can also
use batteries (9-volt) in an emergency....
The power supply and signal splitter works just
like the "Rick-O-Sound"(tm) module and has jacks
where you pick off and go to one or more amps.
I modified the Treble booster with three
switchable output capacitors so I could get various levels of "brightness" out of it.
end of side one

Re: Model 391/12

Posted: Tue Sep 09, 2008 4:23 pm
by admin
I may be off base here, but I have a memory that Mark Thacker used to work for RIC. this would certainly explain his interest in the instrument and the wiring. Perhaps John Hall could shed some light on this customized instrument as well. It is so well done, I would not be surprised to learn that it was Factory work.