370/12 BYRD schematic

242_foxtrot · Post by **242_foxtrot** » Sun Sep 21, 2003 3:07 pm

Looked through Byrds forum trying to find if anyone had a schematic for the 370/12 BYRD. Can anyone help?

mortivan · Post by **mortivan** » Sun Sep 21, 2003 3:17 pm

Here's one on the RIC site for the 370/12RM with onboard compressor:

Guitar, 370/12RM (with E1 option) Roger McGuinn Limited Edition Scematic

242_foxtrot · Post by **242_foxtrot** » Sun Sep 21, 2003 3:46 pm

Thanks John, but I'm looking for a schematic for the original BYRD model from the 60's. I'm thinking of modifying one of my 12 strings.

rick12dr · Post by **rick12dr** » Sun Sep 21, 2003 4:49 pm

Why do you want the original Byrd circuit?? Unless you "just gotta have it"[some of us are like this; go figure]consider you can NOT get Any combinations of PUs with this setup.Now, if you want the pickguard setup to Look like a Byrd, but function better internally, I have a clone of my old factory modded '68 360/370-12 pickguard I could make for you.

kranz · Post by **kranz** » Mon Sep 22, 2003 1:49 am

The following is a description of the Byrd wiring generously provided to me at one time by "Tomcat". I hope he won't mind sharing it with y'all.

Upper toggle switch (closest to the pickups) - Pickup selector

-Up position: Neck pickup only
-Middle position: Middle pickup only
-Down position: Bridge pickup only

This is a special multi-bladed Switchcraft toggle.
(I think it has someting like nine blades.)

Lower toggle switch (farthest away from the pickups) - Pre-set tone selector

-Up position: Heavy low-pass filter (no jangle)
-Middle position: Medium low-pass filter (still very muted)
-Down position: No low-pass filter (clean; all the jangle)

This was a simple four-bladed Switchcraft toggle, as I recall, and the tone
caps were .047uF and .025uF molded foil capacitors., if memory serves me
correctly. The middle position utilized the .047uF cap only, and the up position
utilized both caps together for a combined .072uF tone capacitance -- assuming my
values are correct. There was no resistance involved in this pre-set tone circuit,
just the tone caps applied directly to the guitar's hot lead at the master
volume according to how the tone toggle was selected.

Lower three knobs - Individual pickup volume controls

Viewing the 370/12Byrd as it sits in its guitar stand, they are:

From top to bottom
-Upper knob: Neck pickup volume
-Middle knob: Middle pickup volume
-Lower knob: Bridge pickup volume

Or, viewing the 370/12Byrd as strapped into a musician, they are:

From left to right
-Left knob: Bridge pickup volume
-Middle knob: Middle pickup volume
-Right knob: Neck pickup volume

These were all 500K potentiometers on my guitar. One outer tab was grounded,
the middle tab was wired to the pickup's hot lead, and the remaining
outer tab was wired to the outer (ungrounded) tab of the master volume pot.
This applied to each to the three slave volume pots.

Upper knob - Master volume control

-Master volume fed two parallel mono output jacks.

This was a 100K potentiometer on my guitar, date-coded 1967, so it was not
the original master volume pot installed at the factory in February 1966.
Then again, McGuinn had an active Vox treble boost circuit in the guitar
during the '60s which may have required a lower output impedence. In any
case, one outer tab was grounded, the middle tab was wired to the two
parallel mono output jacks, and the remaining outer tab was wired to each
of the three slave volume hot leads plus the tone selector lead.

admin · Post by **admin** » Mon Sep 22, 2003 2:03 am

Kranz: Thanks so much for this. It is great to have this information on the Rickenbacker Forum.

terry · Post by **terry** » Mon Sep 22, 2003 4:42 am

That must have been an ancient e-mail or posting, and it was clearly written "off-the-cuff" without the benefit of having the actual components handy at the time (e.g., "as I recall," "if memory serves me correctly," etc.). The three individual volume pots were 250K (not 500K), the 2nd tone cap was .02µF (not .025µF), and the original master volume pot was installed after February 1966. Other than that, the rest of the description seems okay. Hope this helps.

admin · Post by **admin** » Mon Sep 22, 2003 4:48 am

Terry: Would you have any photos of the circuit? I would love to see what it looks like "under the hood!" Also, I would like to add that I have had great mileage (to carry on with the car metaphor)using a 02µF capacitor on the neck toaster pickup of my Model 350. A very pleasant change in the once very bassy tonality of this pickup.

shamustwin · Post by **shamustwin** » Mon Sep 22, 2003 7:40 am

Question: why did McGuinn do this in the first place?

mark_telfer · Post by **mark_telfer** » Mon Sep 22, 2003 10:28 am

Ever-keen on fusing one style with another, Jim presumably liked the wiring on The Byrds' Gretsch Tennessean and wanted to experiment with it on a range of Rickenbackers.

rick12dr · Post by **rick12dr** » Mon Sep 22, 2003 12:45 pm

I believe some earlier Ricks from the 50s had a "tone switch" that may actually be what ended up in the Byrd wiring; anyone got one of these
oldies that could confirm what's "hiding under the hood" in the wiring/switch/cap dept.?

admin · Post by **admin** » Mon Sep 22, 2003 1:04 pm

As an example, the early model 425s had a tone switch.

rick12dr · Post by **rick12dr** » Mon Sep 22, 2003 1:47 pm

That could be what I was thinking of.Or perhaps one of the "Combo" series.Other than pics of them, I have little or no experience with them.
Rick, Gretsch, and Fender[Esquires] all used tone switches.

leftybass · Post by **leftybass** » Mon Sep 22, 2003 2:30 pm

Don and Peter: I have a '62 425; what is it you want to see in terms of the switch? I may be able to send a pic to post...

admin · Post by **admin** » Mon Sep 22, 2003 2:41 pm

Lefty: A photo of the circuit under the guard would be interesting.