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The Sushi Box FX Secret Society

have you ever looked into emulating sag in a tube amp for any of your pedals?
Not really, nope. Someone designed a circuit to be added into high-voltage power supplies to simulate this sag, but I've never tried it out.
 
have you ever looked into emulating sag in a tube amp for any of your pedals? Because then the Firebox can be used in any FX loop to now emulate a true tube power section.
There's more to a true tube power section than sag - it's an interaction of phase inverter topology and distortion, power tube saturation, output transformer frequency response and saturation, interaction with the varying impedance of the speaker, negative feedback.... And I'm not so sure sag is as relevant for bass as for guitar.

But as long as we're on this general topic... @Sushi Box FX, have you ever looked into making small tube power amps, modeled after some large tube amps but scaled to lower power? My wish list for such a product is: a choice of balanced (XLR) and unbalanced (1/4") inputs; an input buffer, some gain, and master volume control; a power section modeled after the Fender Showman* but with tiny output pentodes; a reactive speaker load built in; and balanced DI, unbalanced line, and speaker outputs.

This probably wouldn't be a pedal, it would live next to a big clean power amp and speakers. It would, of course, pair very nicely with the existing Sushi preamp and effects pedals.

* A Showman driven just over the edge of breakup is one of my favorite bass sounds, think early Phil Lesh, Jack Casady and Chris Squire. Substitute other power amp topologies for different models - Ampeg SVT would probably be a good choice.
 
But as long as we're on this general topic... @Sushi Box FX, have you ever looked into making small tube power amps, modeled after some large tube amps but scaled to lower power? My wish list for such a product is: a choice of balanced (XLR) and unbalanced (1/4") inputs; an input buffer, some gain, and master volume control; a power section modeled after the Fender Showman* but with tiny output pentodes; a reactive speaker load built in; and balanced DI, unbalanced line, and speaker outputs.
That would be a very large, very expensive box.
 
There's more to a true tube power section than sag - it's an interaction of phase inverter topology and distortion, power tube saturation, output transformer frequency response and saturation, interaction with the varying impedance of the speaker, negative feedback.... And I'm not so sure sag is as relevant for bass as for guitar.

But as long as we're on this general topic... @Sushi Box FX, have you ever looked into making small tube power amps, modeled after some large tube amps but scaled to lower power? My wish list for such a product is: a choice of balanced (XLR) and unbalanced (1/4") inputs; an input buffer, some gain, and master volume control; a power section modeled after the Fender Showman* but with tiny output pentodes; a reactive speaker load built in; and balanced DI, unbalanced line, and speaker outputs.

This probably wouldn't be a pedal, it would live next to a big clean power amp and speakers. It would, of course, pair very nicely with the existing Sushi preamp and effects pedals.

* A Showman driven just over the edge of breakup is one of my favorite bass sounds, think early Phil Lesh, Jack Casady and Chris Squire. Substitute other power amp topologies for different models - Ampeg SVT would probably be a good choice.
Rob Robinette changed many amps into smaller 1 watt amps but he used triodes for the power stage, often a single 12AU7 tube to drive the push pull output transformer.
There are many of his designs to choose from, I made one up from his Bassman Micro and used the C2CE power supply to power it, I had to place the output transformer on top so I could get bass frequencies ( Musical Power Supplies transformer ).
My power amp can push out 1 watt and I like it for home use and with Sushi and C2CE pedals.

You can experiment using his designs as much as you like.


 
Rob Robinette changed many amps into smaller 1 watt amps but he used triodes for the power stage, often a single 12AU7 tube to drive the push pull output transformer.
There are many of his designs to choose from, I made one up from his Bassman Micro and used the C2CE power supply to power it, I had to place the output transformer on top so I could get bass frequencies ( Musical Power Supplies transformer ).
My power amp can push out 1 watt and I like it for home use and with Sushi and C2CE pedals.

You can experiment using his designs as much as you like.


This reminds me of @Jim Hagerman 's tube amplifiers.
 
Just broke down and bought a Finally v3. I have a Neptunium on my board, but want to compare the two. I might want the character from the Finally more than the EQ from the Neptunium.

Shootout to happen in 5-14 business days!
I just checked the tracking and my Finally v3 enclosures are set to be here Wednesday, so I should be good to put together a bunch of units starting Thursday.
 
Greenhouse: Just before bedtime, low volume, initial test.
As a clean boost with nothing, or unity gain in the loop, its a pretty subtle, lovely sounding boost.
As a dirty tube overdrive, it sounds authentically Amp - like. I tried a Spaceman Polaris, McSpunkle Gnomeratron, and an Omnicomp, all running clean and hot, with potent results. The Source Audio C4 Synth, with the output slamming the loop, was glorious.
After putting away my bass and rig, I decided to swap the ECC81 (60), with a Tung Sol 5751 (70), to see what a little more gain sounds like in the morning light. Good night Gentlepeople.
Whelp, the 5751 I tried was toast, or somehow incompatible. So I returned to the stock tube, (paid closer attention to the Line/Hi-Z switch on the console I was plugged into) and realized the gain structure as designed was wholly acceptable for my setup. Synth/PLL in the loop is awesome. Just need to be on the lookout for an even bigger knob.
Also, at proper volume the Greenhouse influence is much more apparent.
 
Whelp, the 5751 I tried was toast, or somehow incompatible. So I returned to the stock tube, (paid closer attention to the Line/Hi-Z switch on the console I was plugged into) and realized the gain structure as designed was wholly acceptable for my setup. Synth/PLL in the loop is awesome. Just need to be on the lookout for an even bigger knob.
Also, at proper volume the Greenhouse influence is much more apparent.
synth was one the main situations I had in mind for it, very good to know. my C4 will go on classifieds but I have enzo-x in mind
 
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Nice 45mm knob, if that,s not big enough then go for the 61mm knob, if you need something even bigger then maybe the knob is the....... never mind.


 
the real question you're asking yourself is: which one will go first in the signal chain ?


You know, I hadn’t even considered this. I’ve been running MORE at the front and Finally at the end but I’ve been thinking about how to add a Clean DI at the beginning of the board for recording soooo I guess I’m gonna try Finally + NP and vice versa
 
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Board is complete. Between the Neptunium and the Octabvre showing up this week, it’s been a pretty good mail week.

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