Grateful Dead Music Forum

So I'm expectantly waiting for my TPC-1 I've been still going round in my head on which guitar to put it in and how I want to set it up, when the thought occurred to me to put it in a box rather than a guitar.

And since there's not much new under the sun, I wonder if anyone has done this. And whether ya have or ya haven't, what you think about the idea.

It could be set up with an enclosure something like this, and have a clip to go on belt or guitar strap:



Then a short cable connects guitar jack to box, stereo jack in box for loop in/out, and mono jack out of box to amp. So the major differences from the Jerry-type OBEL are that the signal would not ever re-enter the guitar, and therefore the mechanics (specifically the volume control) would operate a little differently.

There would have to be a volume pot on the box, since the guitar's volume control is now pre-loop. And depending on where the box is, it could be a little awkward to do quick volume changes... but I think it could be manageable after getting used to it.

Other than that, I think all the functionality would be retained.

The advantages are that I could use it with any of my axes, wouldn't have to drill new jack in guitar, and battery changes would be a snap.

Thoughts?

What your suggesting is actually the same thing as a regular effects loop such as the ones built into some combo amps or (as some have made) an external effects loop box/pedal. When it's off, your going direct from guitar to amp. When it's on your going through your effects and the to amp! It's a viable idea but it disreguards the whole idea of an OBEL (on board effecfts loop). The only reason the have an on board effects loop is so the pickup signal goes directly to the effects in order to utilize the potential of the effects reguardless of where the guitar volume is set. You can put a pre amp/buffer (such as Walso's) in any guitar, with out the OBEL. The pre amp/buffer does not have to go hand and hand with the OBEL, but work well together. For instance, I have the pre amp/buffers in all my guitars, but only have the OBEL with the pre amp/buffer in one guitar so far. The guitars with just the per amp/buffer sound exactly the same as the one with the OBEL except you have to have the guitar volume all the way up in order for the effects to respond well.

Yes a few have used buffers and blasters in enclosures so they can use multiple guitars with them. I am sure you will have success, but still have the volume/signal issue, thus not being a true Jerry OBEL as stated above. The Jerry OBEL traditionally was to eliminate signal variables coming from the guitar into the effects. The Mutron especially. That way it is all set it and forget it. It is so nice to have that in a rig if you gig often. Also, the buffer is most optimal coming right off the pickups rather than traveling down more wires and junctions/circuits. The OBEL inside the guitar is the cleanest package IMO, a Jerry rig is confusing enough without adding more boxes . If you can get the guitar OBEL out to be full blast to effects or (pre-volume knob) it should work fine like a Jerry version. Have all the tonal/volume adjustments on the box (as per picture) to be post OBEL. Have your guitar tone be pre OBEL though, it helps with tone with the OD pedals, i think.

hippieguy1954 wrote:What your suggesting is actually the same thing as a regular effects loop such as the ones built into some combo amps or (as some have made) an external effects loop box/pedal. When it's off, your going direct from guitar to amp. When it's on your going through your effects and the to amp! It's a viable idea but it disreguards the whole idea of an OBEL (on board effecfts loop). The only reason the have an on board effects loop is so the pickup signal goes directly to the effects in order to utilize the potential of the effects reguardless of where the guitar volume is set. You can put a pre amp/buffer (such as Walso's) in any guitar, with out the OBEL. The pre amp/buffer does not have to go hand and hand with the OBEL, but work well together. For instance, I have the pre amp/buffers in all my guitars, but only have the OBEL with the pre amp/buffer in one guitar so far. The guitars with just the per amp/buffer sound exactly the same as the one with the OBEL except you have to have the guitar volume all the way up in order for the effects to respond well.

you should probably rethink that. he described nothing similar to a combo amps effects loop, which places your effects between the preamp and poweramp.

This could be a viable option. the only thing that would really be different is that there would be a cable between the pickup signal and the preamp. I dont know if a short cable of top notch materials and connectors would really make a difference. If you designed your guitar to output the signal from your pickups directly to the box and put the volume control inside the box with the pedal board return coming back into the box into the volume pot and out to the amp.

I would much rather have all of this contained inside the guitar. but if you're wanting to use the idea with multiple guitars and/or want to use the OBEL without defacing a a vintage guitar or an axe without extra room. this would be a great idea. I was originally thinking you would want to bypass the guitars onboard volume pot, but i suppose you could actually use it as a pre-FX volume control and the onboard box could be a post fx volume control. I believe I've read that running through multiple volume pots can do something to your signal, but it wouldnt be as bad as a guitar with indiviudal pickup volume pots running into an overall master volume pot- in a completely passive design.

I doubt the cable capacictance of the cable between the guitars output and the preamp would make a difference.

I was using the effects loop in combo amps as an example. I don't think he wants to do that. Sorry if it confused you. The bottom line is that using a post and pre volume is almost undermining the whole idea of the OBEL. The simple way to do what he wants is just a small loop box (in order to take your effects out when wanting clean sound and having a direct signal to pre amp). Then just make sure your guitar volume is all the way up when using effects!

Sorry I hadn't managed to get on and reply sooner... but I think claytushawood hit it on the head.

Hippieguy, maybe you're not quite following what I'm saying, because it definitly doesn't "undermine the whole idea of an OBEL" -- in fact, I believe it would work exactly the same. There still could be something I'm missing (which is why I brought it up here in the first place), but I think (and I say this wishing to offer no offense) its possible you're in the mindset of "Jerry did it this way so it has to be this way."

The only reason the have an on board effects loop is so the pickup signal goes directly to the effects in order to utilize the potential of the effects reguardless of where the guitar volume is set.

To see what I am saying, change the last phrase to "regardless of where THE FINAL VOLUME is set."

So if you're in Mutron mode and you want full signal going to the effects, that's where you set the guitar's volume pot. And you still can roll back your final volume, as in a normal OBEL set up, but you now you do this using the volume on the box.

For non-Mutron effects, setting it up as I suggested also does give you the option to turn down the pre-effects signal and still maintain your overall volume -- which could be useful at times (say, to bring an octaver divider in gradually rather than BAM!).

As I see it, sound-wise the only difference betwen my proposal and the standard way is that the preamp comes after the guitar volume pot (as CTW pointed out). Personally, I am skeptical that running through a passive potentiometer is going to make much difference in the final tone, although I admit don't have an experts level of understanding, and grant it could be possible.

The biggest overall difference is in the mechanics -- reaching to a different place (eg, wherever the box is located) to adjust volume.

And I agree with those that said the simplest thing is to have it in the guitar. But because I don't have unlimited resources to throw at my musical toys, and for flexibility, I'm considering this route.

(OK, OK... I also have a tendency to want to do things a little differently. I admit it, and it causes problems at times! )

And I really don't need a new project, but I'll be soldering one way or the other. Jury still out for me.