DEMO When you give yourself a tone job and it gets messy.

[Pauleo1214]

Build Rating

4.00 star(s)

I just finished a guitar for a customer in Florida. It was a fun build and it plays like a dream but boy were the electronics a pain!

It was simple enough until it fubar and I had to pinpoint the issue which was not obvious. Everything is controlled by 8 knobs. They are,
First row
1. Master volume
2. Neck/ Bridge pickup pan
3. Middle pickup blend
4. Magnetic/ piezo pan

Second row
1. Magnetic tone
2. Master treble
3. Master midrange
4. Master bass

I used a Fishman Powerchip as a preamp/ blend for the piezo and magnetic signal. A Box of all EQ was at the tail end of it.

I wired it all up and only got the magnetic signal. A thorough visual inspection revealed no obvious issues. I then found out the tip and ring pads were reversed on the pcb which came that way from Fishman. Upon further testing it, it only worked to blend in the piezo and not pan between magnetic and piezo signals. So out went the Fishman power chip.

The Box of All didn't work either. Fortunately this was a lot easier to diagnose. I knew I was getting 9V from the battery but a quick measure of the circuit protection diode revealed a sever in the trace. The next problem was a bad 250k pot on the treble control.

To fix the piezo panning problem, I wired a GPCB Stage 3 Boost for the L.R. Baggs Bridge. I wired up a Buff n Blend for the magnetic signal and inserted the boost at the return end of the loop, bam, instant panning.

Due to all the pots needing to be wired offboard and the circuits hidden out of view from the bottom f-hole, a spaghetti mess could not be avoided. With all that said here are some messy gut shots and photos of the guitar itself. Cheers!

 

[Feral Feline]

I would have given up after the 3rd or 4th problem; kudos to you!

Gotta like such a versatile guitar that has a built-in giant-bottle opener.

 

[Pauleo1214]

I probably spent over 10 hours on the electronics. With a 50% balance riding on its completion, giving up wasn't an option. The customer is a really cool guy too.

 

[dawson]

Tone job orgy.

Awesome guitar!

 

[Passinwind]

Really interesting, especially since I'm just about to start in on a piezo/mag pickup blend pedal build for a friend's old Gibson acoustic. Still haven't worked out how I'm going to format the EQ(s), especially for the mag pickup. And it needs blended and discrete stereo outputs...oh joy!

 

[Pauleo1214]

Really interesting, especially since I'm just about to start in on a piezo/mag pickup blend pedal build for a friend's old Gibson acoustic. Still haven't worked out how I'm going to format the EQ(s), especially for the mag pickup. And it needs blended and discrete stereo outputs...oh joy!

Sounds like that project's gonna be more fun than a barrel o' monkeys. At least it will be in in an enclosure and not a high gloss instrument you're trying to avoid scratching.

 

[Passinwind]

Sounds like that project's gonna be more fun than a barrel o' monkeys. At least it will be in in an enclosure and not a high gloss instrument you're trying to avoid scratching.

Or worse yet, inside a sweet old vintage instrument with no access save the sound hole. I used to do lots of onboard installs in brand new $$$ basses, quite a few for a fairly high profile NAMM booth, so I feel your pain!

 

[Pauleo1214]

Or worse yet, inside a sweet old vintage instrument with no access save the sound hole. I used to do lots of onboard installs in brand new $$$ basses, quite a few for a fairly high profile NAMM booth, so I feel your pain!

Which is why I put a carved access panel on this. No way in hell am I fishing anything beyond standard volume and tone control through an f hole and pickup cavity.

 

[Passinwind]

Which is why I put a carved access panel on this. No way in hell am I fishing anything beyond standard volume and tone control through an f hole and pickup cavity.

That's a killer instrument BTW.

 

[Pauleo1214]

That's a killer instrument BTW.

Thank you! It's a blast to play!

 

[Pauleo1214]

A quick demo I cut for the buyer. Pardon me saying it has a carved spruce back, I hate talking on camera.

 

[HamishR]

NMK. (Needs more knobs)

 

[Pauleo1214]

NMK. (Needs more knobs)

It was originally going to have 9.

 

[steviejr92]

A quick demo I cut for the buyer. Pardon me saying it has a carved spruce back, I hate talking on camera.

She sounds like a beauty!

 

[jhaneyzz]

You know what he needs next:

 

[jhaneyzz]

A quick demo I cut for the buyer. Pardon me saying it has a carved spruce back, I hate talking on camera.

Absolutely beautiful guitar dude. great work.

 

[HamishR]

D'oh! I missed the bit where you mentioned that you built the guitar! I mean I love making things but that would be so beyond me. Impressive! I wish I could build a guitar because I have one or two ideas... But it would definitely end in tears. Well done!

 

[Pauleo1214]

D'oh! I missed the bit where you mentioned that you built the guitar! I mean I love making things but that would be so beyond me. Impressive! I wish I could build a guitar because I have one or two ideas... But it would definitely end in tears. Well done!

Thank you. The only reason it's shared here is because of the box of all eq inside of it. That and the GPCB stage 3 boost and the GPCB buff n' blend.

Knob placement on this thing was agonizing. That said the gentleman who ordered this likes to compose and record music so this will definitely be intended for the studio.

 

[HamishR]

I once had an Ibanez bass (back in the '80s) which had an active EQ section. It was a great bass - quite a few bands used them at the time. If I remember right it had five knobs: the main volume and balance knobs (balance between the two pickups) were large like normal bass knobs, then underneath were the active EQ knobs which were smaller. It made what might have looked complex look simple and easy to use.

I think the way you have arranged the knobs is as good as you could have done given that there are eight! But if you ever get worried about having eight knobs there maybe you could try using different sizes to help explain their functions?

 

[Pauleo1214]

I once had an Ibanez bass (back in the '80s) which had an active EQ section. It was a great bass - quite a few bands used them at the time. If I remember right it had five knobs: the main volume and balance knobs (balance between the two pickups) were large like normal bass knobs, then underneath were the active EQ knobs which were smaller. It made what might have looked complex look simple and easy to use.

I think the way you have arranged the knobs is as good as you could have done given that there are eight! But if you ever get worried about having eight knobs there maybe you could try using different sizes to help explain their functions?

I totally did this before. What made this build a bit more difficult was adhering to customer requirements for layout and use of speed knobs throughout; my hands were tied there.