Author Topic: Ernie Ball VP Jr. mod/buffered splitter  (Read 3381 times)

Tuxedo3

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Ernie Ball VP Jr. mod/buffered splitter
« on: April 07, 2016, 08:28:57 PM »
Hey guys, I have an idea for a VP Jr mod to do, which is basically just implementing a buffer splitter inside the pedal to eliminate the tone suck (very similar to what JHS does, I honestly thought of this before I knew they did it). The issue is that I'm not sure how to take my buffer schematic which is super simple and make it a buffered splitter. Anyone know how to do that/ have any experience modding the VP Jr? Thanks a ton, I can post my schematic if need be.

jubal81

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #1 on: April 08, 2016, 12:40:41 AM »
This is one of those I've been meaning to do. Looks like it'd be pretty easy fit just replacing the PCB and drilling a couple holes.
"If you put all the knobs on your amplifier on 10 you can get a much higher reaction-to-effort ratio with an electric guitar than you can with an acoustic."
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dbp512

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #2 on: April 08, 2016, 02:14:36 AM »
Check out the AMZ buffer-splitter, its the perfect circuit for this purposes.
"you truly are a transistor tickler, what with the application of germanium ointment to sensitive fuzzy areas. :)" - playpunk

Tuxedo3

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #3 on: April 08, 2016, 07:36:14 AM »
Check out the AMZ buffer-splitter, its the perfect circuit for this purposes.

I looked it up, this is just about perfect. Considering I'll only need two outputs it will be a super small board.

This is one of those I've been meaning to do. Looks like it'd be pretty easy fit just replacing the PCB and drilling a couple holes.

Where would you implement the volume pot into the new PCB? I'd assume after the input, before the output.

jubal81

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #4 on: April 08, 2016, 08:46:00 AM »
Check out the AMZ buffer-splitter, its the perfect circuit for this purposes.

I looked it up, this is just about perfect. Considering I'll only need two outputs it will be a super small board.

This is one of those I've been meaning to do. Looks like it'd be pretty easy fit just replacing the PCB and drilling a couple holes.

Where would you implement the volume pot into the new PCB? I'd assume after the input, before the output.


Nope, you'd want the pot after the signal is buffered. The connection to the guitar signal should be very high impedance.
"If you put all the knobs on your amplifier on 10 you can get a much higher reaction-to-effort ratio with an electric guitar than you can with an acoustic."
- David Fair

Tuxedo3

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #5 on: April 08, 2016, 08:52:07 AM »
Nope, you'd want the pot after the signal is buffered. The connection to the guitar signal should be very high impedance.

Oh, that makes so much more sense. So send the buffered signal to the pot.

Tuxedo3

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #6 on: April 08, 2016, 08:29:46 PM »
Nope, you'd want the pot after the signal is buffered. The connection to the guitar signal should be very high impedance.

Also, how do you think you'd fit in the new board? I've designed one but it doesn't have a place to be mounted like the current one is. Any thoughts on that?

jubal81

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #7 on: April 09, 2016, 01:12:19 AM »
Nope, you'd want the pot after the signal is buffered. The connection to the guitar signal should be very high impedance.

Also, how do you think you'd fit in the new board? I've designed one but it doesn't have a place to be mounted like the current one is. Any thoughts on that?


That's where I've left off. I was going to measure the enclosed jacks and make an eagle part for them to mount the new one exactly like the one that's in there. Like a drop-in replacement. I've breadboarded up a nice JFET boost for it and thought I'd use a second JFET for the tuner buffer.
"If you put all the knobs on your amplifier on 10 you can get a much higher reaction-to-effort ratio with an electric guitar than you can with an acoustic."
- David Fair

Tuxedo3

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Re: Ernie Ball VP Jr. mod/buffered splitter
« Reply #8 on: April 09, 2016, 12:28:59 PM »
That's where I've left off. I was going to measure the enclosed jacks and make an eagle part for them to mount the new one exactly like the one that's in there. Like a drop-in replacement. I've breadboarded up a nice JFET boost for it and thought I'd use a second JFET for the tuner buffer.

That's a sweet idea. I wasn't initially thinking about an exact drop in board but that'd be cool and way cleaner. I've been using Diptrace for PCBs and I'm not sure if i'm familiar with adding the holes for that type of on board 1/4 connector. Either way I think it'd be cool to do a board that just goes in place of the current one and utilizes the pot wires just like the EB one does.