Graphtech Hexpander/Acousti-phonic for luddites

[swarfrat]

Ok, so everything is either here or enroute. And I realized last night my controls need some more thinking.

Magnetic setup is two GFS Mean 90's, 3 way blade, vol, tone.  I don't want mini toggles on my guitar. I'm shooting for dirt simple practical functionality.

I thought I really wanted to permanently wire the stereo jack in split mode, and just keep the three systems separate. (Mag, Piezo mono (acoustic), and Piezo hex (MIDI)) but that depends on how useful blending mag & piezo into a guitar amp really is.

If I keep them separate, I can stay with 2 knobs, and use a stacked volume pot.  If use any blended setup, the piezo and magnetics probably need separate volumes, and a switch. I could wire it onto a 4P5T switch, and use the bottom two positions for piezo & blended.

I've decided I don't need MIDI volume or  patch changes on the guitar, and I don't forsee doing MIDI live.

Anyone do something similar? I can figure out the electronics, I'm more interested in the ergos/practical side. Did you leave something off and miss it or put it in and find it really wasn't worth the effort?

 

[line6man]

Are you buffering the piezos to prevent impedance mismatches with the magnetics?

 

[swarfrat]

Yes. In fact, that's pretty much all either of the two units do. Hexpander is a hex buffer, Acoustiphonic is a summing amp + EQ + switching. 

Piezo volume w/o the Acousti-phonic is supposed to be 5M. W/ the unit its 250K.

 

[Steve_Karl]

What I missed was realizing that the acousta-phonic NEEDS to use the included switchcraft 13B output socket.
They've wired it backwards to the rest of the world, i.e. battery *shutoff* is by completing the circuit on the switch in the jack, as opposed to breaking the circuit.

So, my mistake was getting my body routed for a 1/2" thick panel jack.

I'm waiting for the electrosocket to arrive and will have to take it in to be drilled out to 7/8",
so this is just a heads up on that to make sure you have the right size jack to accept the 13B,
which is actually the same size as any old NORMAL switchcraft 1/4", but just has 4 connectors on it.
Tip, Ring, SWITCH, and ground.

G' Luck. I'll be watching for pics and audio clips!


Oh ... and a quick P.S.
The volume pot with the push pull mid/dark option is pretty crappy.
It doesn't do much at all and it actually doesn't get dark. It looses some bottom and gets a bit edgy.

 

[swarfrat]

Thanks for bringing that up - I hadn't discovered that yet.  I'd also considered not wiring up the acoustiphonic to the 1/4 jack at all - and only running the piezos when I used the 13 pin plug which supplies power.  But since I'm going to be Piezo-Operational long before I'm MIDI-Operational, I guess I need the battery and switch. That's now TWO top routed guitars which contain @#$ batteries. And I can't use the upside down jackplate trick on this one. (Even besides looking ugly, I'm using that space - the 13 pin stuff will pass through the jack cavity (planning on drilling for the panel mount jack through the side straight into the strat jack route)

 

[Steve_Karl]

If it were my build, I'd keep them all separate just to have the flexibility when tracking.
It'd be cool to record magnetic, acoustic and midi to 3 separate tracks at the same time, and then do the blend / mix after.

If my nylon strat idea works out for me and I really start to like it, I might tag on the hex board later on.

 

[swarfrat]

There is that aspect of it as well. Simpler controls. More flexibility in the studio. I'd kinda sorta like to try recording hex piezo as well, but it appears none of the boxes actually do that (though its simple enough to make - more so since the Hexpander is already a buffer/amp).

I especially like that this lets me keep my two knob setup. Not a lot of clues that there's anything funky going on under the hood.

 

[swarfrat]

I pondered some more putting in the Stew-Mac sooperdooper switch, whatever they call it. (4P5T) and using the extra two positions to mix in Piezo, but I came up with a couple of problems with that. Mostly that I couldn't come up with a scheme that I thought made sense. Neck/Neck+Bridge/Bridge/Piezo+what??/Piezo  was the best I could come up with.

So the dilemma at hand is: Stacked Vols or ditch the tone knob and go with two vols? I  know most people never ever ever use their tone knobs. I actually fiddle with it once in a while but I think I could probably live without it.  Looking at the pickguard & controls tonight I don't think I can bear to go back to three knobs - it's just so clean.

 

[Steve_Karl]

Well if looks are more important than functionality then loose the functionality for the look.