The Sushi Box FX Secret Society

[bassbrad]

I put an SV-PRE up against my Slampegg, and the Slampegg won! In my setup the Broughton was dark. But when I turned up the treble to compensate, it introduced hiss - whereas the Sushi Box was dead silent and still had more bite! SV had a thickness in the lower-mids that was nice on the D & G strings around the fifth fret, and it does have a very nice overall feel. Having a mid control with selectable frequency is nice, but it lacked the clarity of the Bee. I would still recommend trying one if you have the chance. But it didn’t knock the Bee off my board!
Now I am thinking about getting in on the October run for an Underground Accelerator… for those who have tried both - would you go SMD or hand-wired?

You should bear in mind that the SV-Pre is based on the SVT where the Slampegg Bee is based on the B15 very different creatures, a more fair comparison would be the Slampegg Bee vs the Broughton Fliptop. FWIW SB used to offer the SBVT that may be in revision as we read that would be comparable to the SV-Pre.

 

[Giff]

I might buy a bigger board and eventually a second Sushi when this is fixed. Looking forward to the fix. Will each Sushi need on a board need the fix? I assume the answer is yes, but I could also see it being the case where one pedal that causes the issue is fine as long as a second one is not on the board.

I am very much looking forward to knowing the cure for this as well! I can solder, although I’m not certain I could solder to SMT pads. That scares me a bit.

 

[CH Design]

What!?!?! This should be you’re top priority. Mission number one.

This

 

[Sushi Box FX]

I am very much looking forward to knowing the cure for this as well! I can solder, although I’m not certain I could solder to SMT pads. That scares me a bit.

You won't need to, it's all through-hole solder lug soldering. Depending on the pedal it may involve working in slightly tight spaces (space heater, echosaurus, fluffy kitten, etc), but it's not a complex solder job.

 

[jbybj]

Yeah I've been quietly walking a handful of people through it privately as well as implementing it on all builds from August onward, but the plan is to get a nice walk-through document put together and put up on the website.

Long story short, the problem is caused by the polarity protection I put on the power input to allow the pedals to accept either polarity, and that needs to be bypassed so the pedals become center negative only.

Long story long, I've used a couple different but similar components in that position based on availability, cost, etc., and even within the same component type there are going to be manufacturing tolerances that affect certain parameters. I haven't been able to find the exact number where the problem occurs, but basically what's happening is the circuit's ground is too far removed from the common power ground level. So you could have multiple sushi pedals with different ideas of what "ground" should be, which basically creates what we call a ground loop. If the diodes in the polarity protection were closely matched then they should still be at the same ground level and it wouldn't cause a problem, but when they're too different we see these problems. Also the ground level through this protection diode is going to differ based on the current pulled by the pedal, which means a pedal pulling more current, like a HW pedal compared to an SMD pedal, is going to be more different and more likely to have this ground loop issue.

It took me an embarrassingly long time to realize that this is what's been going on, and there's really no one to blame but me. The good news is that, like I said, it's an easy fix. You literally just disconnect the negative (most likely black) wire on your DC jack from the circuit board and connect it to the input jack sleeve instead. That's it. You move one wire and problem solved. The pedal will no longer work with a center positive power supply, but it still has inline polarity protection on the positive side so it will not be damaged and will still protect the circuit.

Hot damn and Hallelujah! This is tremendous news. Does this fix apply to the old mini tube pedals as well?? Finally, I can engage in one of my favorite pastimes, putting together an ALL Sushi board.

 

[Sushi Box FX]

Hot damn and Hallelujah! This is tremendous news. Does this fix apply to the old mini tube pedals as well?? Finally, I can engage in one of my favorite pastimes, putting together an ALL Sushi board.

So it will depend on exactly how old. Like the REALLY early ones I made used a different form of polarity protection so they don't need it, but that being said it wouldn't actually hurt them, so I guess I could just say yes?

 

[Sushi Box FX]

FWIW SB used to offer the SBVT that may be in revision

Yup, may very well be in revision.

 

[jbybj]

Frankly, the limit of one Sushi Box pedal at a time is the reason I’ve been reluctant to order any more pedals. I’m extremely fond of my Smoke Signal, Slampegg, Lab Rat, and Dr. Wattson, and not being able to stack them made me sad. The Lab Rat stacks well with everything, and now I can fully explore the options.

 

[dedpool1052]

Just peeked "under the hood" of the old Sunnday Drive.
Board stamped v1 and dated 10/2020.

I see there's a trimpot on there.
IIRC, this controls the voltage bias, and unless you have a multimeter and know what you're doing, then leave it the hell alone.

 

[Sushi Box FX]

Just peeked "under the hood" of the old Sunnday Drive.
Board stamped v1 and dated 10/2020.

I see there's a trimpot on there.
IIRC, this controls the voltage bias, and unless you have a multimeter and know what you're doing, then leave it the hell alone.

Yup, correct. I had a mini tube Slampegg come back in for repair because someone had bought it used, didn't know what the trimpot was for, and turned it all the way up.

Please don't do things like that.

 

[dedpool1052]

Please don't do things like that.

Trust me, I left it the hell alone

 

[bassbrad]

Long story short, the problem is caused by the polarity protection I put on the power input to allow the pedals to accept either polarity, and that needs to be bypassed so the pedals become center negative only.

You literally just disconnect the negative (most likely black) wire on your DC jack from the circuit board and connect it to the input jack sleeve instead. That's it. You move one wire and problem solved. The pedal will no longer work with a center positive power supply, but it still has inline polarity protection on the positive side so it will not be damaged and will still protect the circuit.

Read the book, waiting for the movie!
Coming soon! We hope!

 

[Killing Floor]

Yup, may very well be in revision.

View attachment 4829560

Need

 

[dedpool1052]

Yup, may very well be in revision.

View attachment 4829560

Would love to try this against my SV-PRE.

Same size as the DW?
Or SS?

 

[Sushi Box FX]

Would love to try this against my SV-PRE.

Same size as the DW?
Or SS?

Same size as SS. Original SBVT was based on the modern SVT which is a two-tube preamp, SBVT II is based on the vintage SVT which is a three-tube preamp so we need a bigger box.

 

[Ryan L.]

Same size as SS. Original SBVT was based on the modern SVT which is a two-tube preamp, SBVT II is based on the vintage SVT which is a three-tube preamp so we need a bigger box.

Good grief.

Shut up and take more of my money, I guess.

 

[Giff]

I.AM.IN.LINE.
UA - HW!
WOO!

 

[Sushi Box FX]

Customer: Echosaurus is a really great pedal, I really can't find anything wrong with it, there's nothing that needs to be changed. I especially love the small size and the low price.

Me, a businessman: Noted.

 

[Sugarbear08]

Fortunately, we've found a cure.

View attachment 4829529

I'm familiar with the cure: I've been using since the August build.

 

[DrHooper]

Yup, may very well be in revision.

View attachment 4829560

I need to figure out a way to just sign my paychecks over to you...


Probably good that I don't know how to do that