Enchanted Boost (JHS Prestige) but make it buffered bypass?

[coltonius]

I purchased an Enchanted Boost PCB during the recent sale, and while downloading build docs I noticed it's set up for true bypass. Since the ad copy for the "original" touts its usefulness as a buffer, I am thinking of wiring mine that way.

For those who've already built it as true bypass: Does rolling the pedal's Volume knob back to minimum maintain unity gain?

If so, I'm thinking of wiring it like a BJFE/Bearfoot Baby Pink Booster, where the In/Out jacks go straight into the board and the footswitch disconnects the wiper in bypass.

 

[Paul.Ruby]

Not unity gain. But might not matter if close enough? If you turn the volume all the way down, does everything work that way you want? If so, good enough. Alternatively, a tiny jfet or BJT (source or emitter follower) buffer would be very easy to add in the bypass path. I think I've seen little boards that mount on the footswitch that have the buffer on them already.

Simple JFET Buffer - PedalPCB.com

JFET Buffer

www.pedalpcb.com

C-Buffer - PedalPCB.com

Compare to Cornish Buffer

www.pedalpcb.com

 

[coltonius]

Not unity gain. But might not matter if close enough? If you turn the volume all the way down, does everything work that way you want? If so, good enough. Alternatively, a tiny jfet or BJT (source or emitter follower) buffer would be very easy to add in the bypass path. I think I've seen little boards that mount on the footswitch that have the buffer on them already.

Simple JFET Buffer - PedalPCB.com

JFET Buffer

www.pedalpcb.com

C-Buffer - PedalPCB.com

Compare to Cornish Buffer

www.pedalpcb.com

I haven’t finished building it yet- I keep meaning to breadboard and try, but other projects keep popping up.

My question was out of curiosity since the original is buffered bypass; I don’t mind if it’s a little above unity, as long as it’s not below. Needing a buffer itself isn’t the concern, I just wondered whether I could take advantage of it for that purpose without adding extra circuitry since that’s how JHS touts the original (ie., Is it a booster that can work as an effective buffer when bypassed or just a boost?).

 

[Paul.Ruby]

I don't have the components to prove it but I would be surprised if below unity. It's probably higher. The signal at the FET gate is 1/3rd of the incoming signal when all the way down and I would be surprised if the gain stage is less than 3X to recover that.

 

[Sturdag Lagernathy]

? At full CCW, the mosfet is set for unity gain. Am I missing something? It should be very close to unity as drawn..

 

[Robert]

My question was out of curiosity since the original is buffered bypass;

The original is not buffered bypass. It's a "buffer" with the boost set to minimum.



You could make it buffered bypass with a little hackery, if that's what you want. Bypass the 3PDT entirely except for the LED switching, wire it so it's always on, and use the 3PDT to short lugs 1 / 3 of the Volume pot.

 

[coltonius]

? At full CCW, the mosfet is set for unity gain. Am I missing something? It should be very close to unity as drawn..

No, you haven’t missed anything. I was just looking for confirmation that it is.

The original is not buffered bypass. It's a "buffer" with the boost set to minimum.

View attachment 70314

You could make it buffered bypass with a little hackery, if that's what you want. Bypass the 3PDT entirely except for the LED switching, wire it so it's always on, and use the 3PDT to short lugs 1 / 3 of the Volume pot.

Ah, I thought it was. My bad! Based on my false assumption, I was wondering whether it could be switched like the Baby Pink Booster:



BPB is:
• Input Jack — In
• Output Jack — Out
• Footswitch connects Boost lug 2 to ground and illuminates the LED.

I will probably stick with true bypass on this one.
___
Thanks for the help, everybody!

 

[Feral Feline]

Late to the party.

Looking at the Enchanted schematic, its lone pot is in the signal-path before the transistor (well, on its Gate); there is no gain adjustment off the MOSFET's Source (goes straight to ground) like there is on the BPB's JFET.

To kajigger something similar to the way the BPB bypass works in the schematic above (post #7), I'm GUESSING you'd want to use a boost that adjusts its gain from the Source leg... such as a SHO.






I suppose that's possible, a BPB-style bypass on the Zeevecks SHO... maybe Seemoor Dunkin Pickup Booster, Cat-bread Nagging Vyper, Keeleh Jabba Boost, EeQueueDee Ecchymosis-Shiner... maybe, maybe even something op-amp based, ie short the resistance in the feedback loop?


LOOK!

It's a VIA! no​

It's a Ground-Plane, no​

It's BREADBOARD BLOKE!​