The Sushi Box FX Secret Society

[MascisMan]

Frosted mini wheats today, but I get the off brand in the big bag because they have more frosting than the original.

A scholar and a gentleman

 

[Sushi Box FX]

Something just isn't right. The circuit on the board can't be the circuit in the schematic. A 5.6 M R16 would be 4.8% of the original output. A 26.4 dB reduction.

Yup, that's what has us pulling our hair out. Even with 250k to ground a 5M6 in line should completely strangle the signal.

 

[psychovox]

This is fantastic. It's like watching a riveting mystery thriller. But I have a Dr. Wattson on order for this month, so I actually have a stake in the outcome. It's way better than a TV show!

 

[labeledbass]

@Sushi Box FX could you increase R23 value? Lowering plate voltage with R12 or a resistor after C12? And as of right now, running the volume/master so low, it's really only using the V1 tube correct? To bad you can't add a little step down transformer in there, that would be cool. Patiently awaiting instruction, with your permission could I pass this along to my local "tube" guy? He's designed many pre/power amps, only valve

 

[40Hz]

But he never shows us what he had for breakfast. Disturbing.

Frosted mini wheats today, but I get the off brand in the big bag because they have more frosting than the original.

Wah!!! Hope we don't have too many of these.

I'd rather not see this thread degenerate into a ton of 'much ado about nothing' posts like you see in some effects threads. Fun is fun. But it's been done...and done...and done...and done...elsewhere. It was funny and cute at first. But it's gotten kinda old IMO.

 

[kranahan]

Wah!!! Hope we don't have too many of these.

I'd rather not see this thread degenerate into a ton of 'much ado about nothing' posts like you see in some effects threads. Fun is fun. But it's been done...and done...and done...and done...elsewhere. It was funny and cute at first. But it's gotten kinda old IMO.

View attachment 4166625

Here’s the fun police rearing its ugly head.

 

[Pedalnetics]

@Sushi Box FX could you increase R23 value? Lowering plate voltage with R12 or a resistor after C12? And as of right now, running the volume/master so low, it's really only using the V1 tube correct? To bad you can't add a little step down transformer in there, that would be cool. Patiently awaiting instruction, with your permission could I pass this along to my local "tube" guy? He's designed many pre/power amps, only valve
View attachment 4166528

Funny you mention R23. I got bored and replaced mine with a 20k, and it's still louder than crazy. Truthfully I don't feel it did anything different.
I'm totally at a loss myself, I'm starting to remove random stuff for fun to see what happens

 

[kranahan]

Here’s some fun!

 

[40Hz]

Here’s the fun police rearing its ugly head.

If you say so. At least my SO thinks I’m moderately good looking.

 

[labeledbass]

Funny you mention R23. I got bored and replaced mine with a 20k, and it's still louder than crazy. Truthfully I don't feel it did anything different.
I'm totally at a loss myself, I'm starting to remove random stuff for fun to see what happens

I'm wondering if both R12 and R23 have to change, but R12 should directly effect the plate voltage, whole idea behind these are a correct/high plate voltage so that would be working in the wrong direction unfortunately. Seriously, may be a lot more to it than this, but what about a resistor after the last cap, is that not the same thing as a fixed volume pedal downstream of the pedal? And I'm work beyond the scope of how much room there is, 4 inches, 4 feet, I don't care, I want this thing to work, sounds amazing, I want to take advantage of that second gain. My studio boost steps it down nicely, but only enough to use the first stage

 

[Ryan L.]

Here’s some fun!

View attachment 4166645

Damn!!

 

[Sushi Box FX]

This is fantastic. It's like watching a riveting mystery thriller. But I have a Dr. Wattson on order for this month, so I actually have a stake in the outcome. It's way better than a TV show!

I'm going to wait to put the Dr. Wattsons for this month together until I have a better path forward for them.

@Sushi Box FX could you increase R23 value? Lowering plate voltage with R12 or a resistor after C12? And as of right now, running the volume/master so low, it's really only using the V1 tube correct? To bad you can't add a little step down transformer in there, that would be cool. Patiently awaiting instruction, with your permission could I pass this along to my local "tube" guy? He's designed many pre/power amps, only valve
View attachment 4166528

I'm wondering if both R12 and R23 have to change, but R12 should directly effect the plate voltage, whole idea behind these are a correct/high plate voltage so that would be working in the wrong direction unfortunately. Seriously, may be a lot more to it than this, but what about a resistor after the last cap, is that not the same thing as a fixed volume pedal downstream of the pedal? And I'm work beyond the scope of how much room there is, 4 inches, 4 feet, I don't care, I want this thing to work, sounds amazing, I want to take advantage of that second gain. My studio boost steps it down nicely, but only enough to use the first stage

I have really great answers to this, but I'm about to eat dinner and I'm on my phone, so I don't think my thumbs are up to the task. I'll get back on the computer tonight and write more coherently.

 

[Rich48]

Not seeing the light at the end of the tube. So I just swapped out the tube in my Slampegg with a reissue Mullard 12AX7. Everything seems to be working fine. All of the controls on the pedal work. It sounds a little more warm and smother then the stock JJ tube. However I do not see any tube glow at all looking into the box. The box does warm up a bit after being turned on. If the tube were installed wrong or not working would I still be getting sound out? Is not seeing any tube glow normal for this tube?

 

[Sushi Box FX]

Not seeing the light at the end of the tube. So I just swapped out the tube in my Slampegg with a reissue Mullard 12AX7. Everything seems to be working fine. All of the controls on the pedal work. It sounds a little more warm and smother then the stock JJ tube. However I do not see any tube glow at all looking into the box. The box does warm up a bit after being turned on. If the tube were installed wrong or not working would I still be getting sound out? Is not seeing any tube glow normal for this tube?

So 12AX7 will never glow as brightly as 6N21B, as the brightness of the filament is a reflection of how much current they pull, and 12AX7 pulls much less than other tubes. Some brands do glow brighter than others. I know for JJ/Tesla you have to look at the tube from just the right angle to see the glowing filament, other brands I would imagine being similar. I have a couple NOS tubes where the filaments are pretty well concealed by other parts of the tube and you can't really see the glow at all. If the tube wasn't heating up then it wouldn't pass signal.

I'm wondering if both R12 and R23 have to change, but R12 should directly effect the plate voltage, whole idea behind these are a correct/high plate voltage so that would be working in the wrong direction unfortunately. Seriously, may be a lot more to it than this, but what about a resistor after the last cap, is that not the same thing as a fixed volume pedal downstream of the pedal? And I'm work beyond the scope of how much room there is, 4 inches, 4 feet, I don't care, I want this thing to work, sounds amazing, I want to take advantage of that second gain. My studio boost steps it down nicely, but only enough to use the first stage

Alright, so this ties in nicely to a discussion @Sonicblaze and I were having earlier today. We were discussing different modifications that would drop the output level of the pedal to a more usable range. Lowering the value of R12 and/or raising the value of R23 would certainly do it as this would re-bias the las gain stage and make it drive less hard. It would most certainly work, and since we're not touching the tonestack or the other two gain stages I'm sure it would keep that beautiful Hiwatt tone. But changing the bias on the gain stage has a big part in the tone, which brings me to the same question I asked between LA-1A and Deep Dish: is this being EXACTLY the Dr103 preamp important, or is it being "inspired by Dr103" and having the general Hiwatt flavor while being more usable as a stompbox important? My personal opinion is that the latter is more important, which is obviously why my "based on LA-1A" compressor has 2 tubes and no boost, but obviously I'm not the one that buys most of my pedals (though I still do "gift" myself one or two a month).

If I were given free rein to do what I want (which I technically am, I just really want to keep as many people happy as possible, which is why I'm on here daily finding out what you guys like and don't like) I would remove the third gain stage altogether. This would check all the boxes for me:

• Lower output level
• Master volume would go at the very end of the circuit
• Drops to a single tube pedal which means less space, less power required, and lower price
• Currently nobody has been using 100% of the gain available anyway because it's too damn loud
• Two gain stages allow plenty of gain anyway, and it will still drive heavier than PA or LU

I'm still going to try the mods to make it work better as-is, but it also wouldn't be very difficult to mod it to bypass the last gain stage, so I plan to try that out as well. If I like how it sounds I'll get a clip or two so you can hear it and see what you think. Again just my opinion on how I think it would work well, what does everyone else think?

 

[MascisMan]

Here’s some fun!

View attachment 4166645

Deep Dish review much appreciated.

 

[aekisz]

The unique tone of the original design is more important to me than the gain issue. If the fix makes it sound more like your other pedals then I would probably change my order to a Slampeg.

 

[Sushi Box FX]

The unique tone of the original design is more important to me than the gain issue. If the fix makes it sound more like your other pedals then I would probably change my order to a Slampeg.

I should clarify a little better, removing the last gain stage won't make the preamp sound less like a Hiwatt or more like something else, it would still be completely Hiwatt voiced with Dr103 gain stages and a Dr103 tone stack, frankly I'm not sure if there would even be a noticeable difference in sound, just a more usable volume control and less maximum dirt. But duly noted, thanks.

 

[labeledbass]

So 12AX7 will never glow as brightly as 6N21B, as the brightness of the filament is a reflection of how much current they pull, and 12AX7 pulls much less than other tubes. Some brands do glow brighter than others. I know for JJ/Tesla you have to look at the tube from just the right angle to see the glowing filament, other brands I would imagine being similar. I have a couple NOS tubes where the filaments are pretty well concealed by other parts of the tube and you can't really see the glow at all. If the tube wasn't heating up then it wouldn't pass signal.


Alright, so this ties in nicely to a discussion @Sonicblaze and I were having earlier today. We were discussing different modifications that would drop the output level of the pedal to a more usable range. Lowering the value of R12 and/or raising the value of R23 would certainly do it as this would re-bias the las gain stage and make it drive less hard. It would most certainly work, and since we're not touching the tonestack or the other two gain stages I'm sure it would keep that beautiful Hiwatt tone. But changing the bias on the gain stage has a big part in the tone, which brings me to the same question I asked between LA-1A and Deep Dish: is this being EXACTLY the Dr103 preamp important, or is it being "inspired by Dr103" and having the general Hiwatt flavor while being more usable as a stompbox important? My personal opinion is that the latter is more important, which is obviously why my "based on LA-1A" compressor has 2 tubes and no boost, but obviously I'm not the one that buys most of my pedals (though I still do "gift" myself one or two a month).

If I were given free rein to do what I want (which I technically am, I just really want to keep as many people happy as possible, which is why I'm on here daily finding out what you guys like and don't like) I would remove the third gain stage altogether. This would check all the boxes for me:

• Lower output level
• Master volume would go at the very end of the circuit
• Drops to a single tube pedal which means less space, less power required, and lower price
• Currently nobody has been using 100% of the gain available anyway because it's too damn loud
• Two gain stages allow plenty of gain anyway, and it will still drive heavier than PA or LU

I'm still going to try the mods to make it work better as-is, but it also wouldn't be very difficult to mod it to bypass the last gain stage, so I plan to try that out as well. If I like how it sounds I'll get a clip or two so you can hear it and see what you think. Again just my opinion on how I think it would work well, what does everyone else think?

I like what it does now, is it possible to add a resistor at the very end or is it more complex than that?

 

[aekisz]

I should clarify a little better, removing the last gain stage won't make the preamp sound less like a Hiwatt or more like something else, it would still be completely Hiwatt voiced with Dr103 gain stages and a Dr103 tone stack, frankly I'm not sure if there would even be a noticeable difference in sound, just a more usable volume control and less maximum dirt. But duly noted, thanks.

The character of the dirt in the demos is what attracted me. If that is not achievable with the loss of gain that would be problem for me. Sounds like maybe that won’t be an issue.

 

[Sushi Box FX]

Well I did some more mods to my Dr. Wattson and went to plug in....

...turns out I've soldered and de-soldered so many times in the same general area that pads are lifting and I broke a couple connections, so before I continue trying out mods I will need to repair my board That's going to wait until tomorrow.