Grateful Dead Music Forum

pickups>tied to tone pots>5 way switch>preamp input>preamp output>OBEL mini toggle>stereo jack #1 ring>effects>stereo jack tip>vol pot>stereo jack #2 tip>amp

Waldo should be able to clear this up for sure, but I thought that the OBEL jack used the TIP-send-to-fx, RING-return-from-fx routing, the opposite of what you just listed. I could be wrong. It would be cool if we all adhered to an OBEL send/return standard so our guitars would be interchangeable in OBEL rigs.



Brad

yeah...i debated on the ring/tip for the first jack. the second jack us definitely tip for the send, so it would make sense that tip should be send for the obel.

does it actually matter as long as you're consistent?

There is more than one way to wire the OBEL so that it will work correctly. You've outlined one of them. Mine goes pickups --> 5-way selector switch --> tone pots --> preamp --> OBEL switch (push/pull) --> stereo jack tip --> router --> effects --> router --> stereo jack ring --> volume pot --> mono jack --> router --> amp. I wanted my effects to see my signal at full volume and tone, so I put the pots after the loop. I had the ring on the stereo jack be the return because it's alliterative and that way I could remember how it was supposed to go while I was wiring it. I used a preamp design that required a bipolar power supply, so I have a separate battery switch instead of using a stereo jack to send the -9V to ground.

I think the main idea is that we all try to agree on a standard so that our routing devices and guitars and all the OBEL-equipped guitar makers can keep this system universal. Sure we can make our own version if we want, but it's for these other reasons I mentioned that is why we may want to keep consistent with eachother.

I disagree with the previous post with the placement of the tone pot circuit. Tone pots and cap values are designed to have a direct and passive connection to the pickup itself, NOT after the signal has been buffered and isolated. You won't get the same resonant shift response with your tone controls if you don't have them tied directly to the pickups and BEFORE the buffer/preamp. Having the tone control before the buffer and before the distortion pedal is central to achieving that special "tone-off", horn-like quality that we enjoy with Jerry sound. A post buffered tone control just won't do that sound. Also, since tone control circuit cap values are "impedance dependent", you would have to re-calculate the tone pot and tone cap values to achieve a useful treble rolloff frequency in the tone control.



Brad

The few times I've wired 'em up I send on the Tip and return on Ring . The "R" thing keeps me from forgetting (R)eturn on (R)ing.

Got that from boating: Keep the (R)ed buoy on the (R)ight when (R)eturning.

Well, Brad, you certainly know a lot more than I do about electronics, so I had a look at my schematic to see what I did. I have the tone pots coming off the 5-way switch, so I guess that means they're before the effects loop, right? I'll edit my post to reflect reality.

I have to agree with Brad with the tone thing, I wired a Les Paul (before I knew what the hell I was doing) with all the pots after the signal processing and the tone pot didn't work right at all. The range was wacky and the tone was not Jerry like. I thought the tone pot is connected directly to the 5 way by way of the cap's legs separate (parallel?) to the line going to the buffer. Just giving it my best shot here...

These diagrams seem to clarify things for some of us. Brad explains it very well, also.


Pickup only wiring:

http://img203.imageshack.us/img203/7080 ... gsmall.jpg



All other wiring:

http://img294.imageshack.us/i/wiringnop ... llwid.jpg/

hippieguy1954 wrote:These diagrams seem to clarify things for some of us. Brad explains it very well, also.


Pickup only wiring:

http://img203.imageshack.us/img203/7080 ... gsmall.jpg



All other wiring:

http://img294.imageshack.us/i/wiringnop ... llwid.jpg/

Cool..thanks, I haven't seen these before

I think there is/was one small error in those photos- I think the connections for one of the pickups on the double (250/500) tone pot are reversed. See the original thread on page 2 of the guitar construction & mod section.

TI4-1009 wrote:I think there is/was one small error in those photos- I think the connections for one of the pickups on the double (250/500) tone pot are reversed. See the original thread on page 2 of the guitar construction & mod section.

Yea, I see what your talking about. I'm not sure if it matters which outer lug (on the tone pot) the gound is connected to, but I wired them both as shown for the 500k just to be sure and it works fine.

Twice now, an "other thread" has been mentioned with no link to it posted.

so you guys are actually getting into altering the electronics inside the guitar to achieve a Jerry tone? versus just grabbing a premade guitar and matching it with pedals and certain amps? That's pretty hardcore

tiffcheese wrote:so you guys are actually getting into altering the electronics inside the guitar to achieve a Jerry tone? versus just grabbing a premade guitar and matching it with pedals and certain amps? That's pretty hardcore

You can get very close to Jerry tone with just a good tube amp and a few pedals. After all, that is what Jerry did in the early years, but if you want to get the tone Jerry developed (as the years went on) you have to get into the modifications he developed.

Check it out here:

http://www.wald-electronics.com/