I haven't tried to do any specific Byrds mods, but I have tried a bunch of mods with varying levels of success (they all worked, but some seemed to offer more than others). I'm not sure that I can even remember all the wiring details, but I'm certainly no electronics wizard, so they can't be very hard to figure out. I started with my 360/12 WB (twin high-gains) and my former 360/12 (toasters). First, I switched pickups around, playing with various combinations. I wound up eventually selling the 360 and keeping the WB with twin toasters. Then I decided to add a middle pickup, bought another toaster and installed it. I originally wired it in with the neck pickup, like a stock 370, and was surprised at how little it added to the sound. So, I added a 3-position mini-toggle between the four main knobs which would add the middle pickup to either the neck or bridge circuits, or simply turn it off. This did give me more sound variety, but it still wasn't a drastic addition to the available tonal pallette, compared to the standard 2-pickup 360-style wiring.
About this time, I also bought a Ric-O-Sound box. I was surprised at two things about it....(1) that I had paid that much money for a box with nothing more than a couple of solder joints inside of it, and (2) that Ric-O-Sound-style stereo didn't really do anything that I thought added all that much. I love the sound of a 360/12, and so far, I hadn't managed to do anything that really improved on it much at all. The box was returned and I had a couple long, double cables custom made with high-end components for less money, in case I wanted to continue to play with stereo. I have been using stereo (actually double-mono) basses with two cords for almost 40 years, so I know what I want stereo to do and figured that I could always use the cables for bass if I didn't find a use for them on the twelves.
The next experiment was to replace the stereo output jack with a standard one and leave the 2-pickup, 5-knob, 360-style wiring alone, but run it only to the "normal" (upper/mono) jack position. I then give the middle toaster its own circuit and a mono output jack in the former ROS jack position. I added a sixth knob, which is a volume pot for the middle pickup (no cap used and no tone pot) and the only connection to the neck/bridge circuit is that both circuits are grounded to that ring of ground wires running around the cluster of pots. I actually like this configuration a lot. A cord plugged into the normal output jack gives me a standard 360 system. If I want to, I can also plug into a different amp, stomp box, etc. by running a second cord from the former ROS jack and send the middle pickup wherever I want it to go. I can, for example, run the neck bridge circuit through the JangleBox and mix in some non-jangled, natural tone on another track, amp or channel using the middle pickup circuit.The raw middle pickup, by the way, has very nice tone and as you might expect is kind of like a typical neck/bridge blend - with more twang than the neck alone and less twang than the bridge alone. I've also found it handy to have a "spare" track of unadulterated Rickenbacker tone when I record the twelve. It can be mixed in with the track of neck/bridge/effects or JB as needed if I want to water-down the effects. Instead of ROS, where the neck goes one way and the bridge another way, I'm sending a complete, usable Rick 12, neck /bridge mixed signal one way and a second one that sounds similar the other way and putting each one through whatever effects I want. Any time I don't want to mess with dual systems, I just plug a plain old guitar cord into the normal circuit and have a 360/12, which as we all know, ain't half-bad all by itself.
My 330/340/12 is wired the same way - except it only has one output jack. I changed the jack to a stereo jack. The neck/bridge combo uses the mono part of the stereo output jack and plugging in a regular guitar cord gives me a stock 330/12. If I plug in a stereo Y-cord, the middle pickup and it's sixth knob volume pot lead to the stereo part of the output jack and the second leg of the Y-cord, giving me the additional second signal to play with.
Confused yet???? It gets worse.....The final mod experiment for the 370 was adding an onboard treble booster. I found a diagram of the old Vox booster and John built me one to try. I decided to add it only to the middle pickup circuit, so that I could blend it into the overall double-mono mix as desired, right on the guitar using the middle volume pot. I would also need to stick a battery inside the guitar and needed to be able to shut it off when not in use to preserve battery life. I traded out the middle volume pot for a push-pull pot. Pulling the pot out would turn on the booster and pushing it in turned the booster off. Turning the knob still controlled the middle pickup volume, boosted or not. I then replaced the second output's jack with a switched jack (like the normal jack on your 360). When you plug a cord into it, the switch makes an additional contact, in addition to just making guitar sounds (part of the stock ROS wiring system) - only I set mine up so that the contact it made was to connect the battery to power the booster. Unplug the guitar when done playing and it disconnects the battery. The booster circuit itself was a small circuit board stuck in between the middle pickup and the switched output jack.
This system actually worked very well. The push/pull pot turned the booster on and off, the volume knob worked fine and the switched jack only tapped the battery power when the guitar was plugged in and the middle circuit was being used. Plus, a simple normal cord in the other jack would still yield my good old, un-modded 360/12 any time I didn't want to mess with more complex stuff. the only problem was that the design of the original booster circuit sucks. It's incredibly harsh-sounding and very noisy. John built it as shown, but it's just not up to modern standards for clean, quiet operation.
I disconected it and returned to the previous, double-mono configuration. There is a little compressor for internal installations called an "Orange Squeezer" that could be rigged the same way and could be worth trying, but I havent heard one and at only $80 I wonder whether it's decent and reasonably quiet. Don't tell Steve, but I must admit that I have taken a look inside my JangleBox and wondered how hard it would be to set the knobs (which I rarely mess with) lose the case and stick the board inside the guitar using the same push/pull pot and switched jack? I have a basic dislike for having to drag stomp boxes around with me. Luckily, the JB is so nicely assembled that it's too nice to mess with.
Anyway, to make a long story less long, that's the Cliff Notes version of my wiring mods. The collectors and purists have probably all died from heart failure by now, but the guitar still looks great and the final configuration does add something I can use to an already great sounding guitar. You can hear it in action with a bunch of sound samples here:
http://webpages.charter.net/tbradshaw/M ... amples.mp3
(except for the last one, which is my '69 Hagstrom 8-string bass and someone who can actually sing - the rest are a little in-bred because I had to play all the parts myself, but the twelve sounds great).
For the next chapter in this epic, some day I'll tell you about the 1958 Mapleglow Capri that I had turned into a fretless bass in 1974..........
