# Celsius Preamp (Boss CE-1 Preamp) -Update Noise issue FIX!



## MichaelW (Aug 9, 2022)

*Update: 12-16-22*

@Robert has released a revised version of this board to address the "white noise" hiss reported by a number of folks.
The hiss was tolerable playing clean or with low gain but kick in a higher gain pedal and it got pretty distracting.

It was a shame because I really like the subtle coloring this pedal added as a boost. It wound up on the pedal shelf.

When revised pedal was released @Robert offered to send me a new board or try the mod to my existing build. Never one to back down from some squeamish surgery I decided to try the mod first.

I had forgotten that I had already semi-borked this board when I installed the wrong pot and pulled a pad removing it. So there was already a flying jumper to fix that. So what's a few more cowboy mods right?  .

Anyway, those of you that have built this pedal and want to try the mod, it's actually pretty simple and *COMPLETELY *addresses the "hiss" issue.

Here's the mod:





So as I was removing the 470n cap at C3, of course I pulled another pad along with part of the trace.....ugh....so I had to run a small jumper underneath the board and run the C3 leg to R2 output.





I decided to do the mod up top where I could have a little more room.





I was surprised as all get out when I fired it up and it all worked! Hahaha....
There is a "slight" attenuation to the gain. But this pedal had TONS of gain to begin with. I could barely crack the knob at the "High Impedance" setting.

With the mod there is still a ton of gain to push an amp.
At the High toggle setting, unity is now around 3 on the knob.
At the Low toggle setting (where there is a bit more coloration) Unity is around 5.

All with no noise.
So glad to put this sweet boost back into rotation!

Thanks @Robert !!



Original post from 8-9-22 below:
******************************************************************************************************************************************
Double dipping on the build reports today.

I was originally planning to post a 2fer build report with these two pedals assuming they would be very similar.

But as I mentioned in my EV Preamp build report, the forum seemed kinda quiet this morning so I went ahead posted that build report separately.

Regarding the notion that these two pedals would be very similar, I could not have been more wrong. This is a very different pedal.

First off, there is a ton of gain in my build. To the point that I'm wondering if I did something wrong. I mean unity is literally about 2 on the amp knob that I used in Low mode. In High mode I can barely crack the pot and I'll be at unity. I don't know if swapping to a linear pot would help or not but I'm thinking about it.

Secondly, I am hearing a little bit of the white noise that @coltonius mentioned in his build report. It's in the background and is there when the pedal is engaged.
I can hear it when I play with my headphones but it's not noticeable through my amp or monitors, but it's definitely there.

Not sure if it's a charge pump issue or as @coltonius surmised a circuit noise floor issue. I don't find it distracting or anything but there is some hiss.
I imagine a real Boss CE-1 would probably do the same thing.

Tonally, it's what I expected, a subtle warmth to the tone and added girth. More noticeable playing clean than with drive. Paired with an overdrive or pushing an amp it sounds like a really hard punching boost.

I really like the way this sounds but somehow I need to tame the output, it's barely usable it's got so much volume.

Tight fit in a 1590B but mainly because my drilling was a skootch off, hence the toggle washer and slightly crooked PCB in the enclosure. Oh and I put one of the 470nf caps in upside down. These little things drive me nuts.

@Bricksnbeatles did you build yours yet? I'd love to hear how yours turns out.


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## Bricksnbeatles (Aug 9, 2022)

Sharp build! 

I haven’t built mine yet— power to my workspace is shut off for the moment until some electrical work gets done. In the meantime I’m just getting graphics together to get printed from Tayda.


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## Bricksnbeatles (Aug 9, 2022)

When you say insane amounts of volume, is it just in the high mode? Based on this video (the Preamp Crunch+ *should* be exactly the same as the Celsius, just with a master volume on the output, and a selectable buffer on the input) it seems that in low mode unity should be around 3:00 and in high mode it should be around 9:00. 





I think adding a 100k volume pot at the output should do the trick. You could probably fit it directly opposite the hi/lo switch if you use a small knob for the master level.


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## MichaelW (Aug 9, 2022)

Bricksnbeatles said:


> When you say insane amounts of volume, is it just in the high mode? Based on this video (the Preamp Crunch+ *should* be exactly the same as the Celsius, just with a master volume on the output, and a selectable buffer on the input) it seems that in low mode unity should be around 3:00 and in high mode it should be around 9:00.
> 
> 
> 
> ...


Yah both on High and Low settings. Low setting unity is (if I were using a normal knob with a pointer at 6:30 for full CCW) about 8 o'clock. High toggle setting unity would be about 7:30. I mean I can barely crack the pot on the High setting and hit unity, and turning it up any more clips my digital interface. I would say pretty insane amounts of volume hahaha.

Hmmm adding a master volume at the output you mean? I could probably try to do that in a non-destructive way with some alligator leads. 

@PedalPCB is there a schematic available for this yet?


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## Robert (Aug 9, 2022)

MichaelW said:


> @PedalPCB is there a schematic available for this yet?



There is, give me just a bit and I'll send it over to you.

Coincidentally the earlier version of the Crunch Ensemble didn't have a master volume control... This _might_ be why it was added.


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## MichaelW (Aug 9, 2022)

Robert said:


> There is, give me just a bit and I'll send it over to you.
> 
> Coincidentally the earlier version of the Crunch Ensemble didn't have a master volume control... This _might_ be why it was added.


No rush dude, take your time.


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## Bricksnbeatles (Aug 9, 2022)

Robert said:


> There is, give me just a bit and I'll send it over to you.
> 
> Coincidentally the earlier version of the Crunch Ensemble didn't have a master volume control... This _might_ be why it was added.


could you pm the schematic to me too when you get around to it? No rush– except what I'm listening to (sorry. terrible attempt at a joke. I'm not even actually listening to Rush rn, so that was a bust.)


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## MichaelW (Aug 9, 2022)

Ok I just watched this vid of the Triungulo version without the master vol. Very interesting the effect it has on the signal integrity in high impedance. I actually like it in High mode better except for the unmanageable volume. 
There's a pretty significant level bump between low and high, which this video shows.


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## MichaelW (Aug 10, 2022)

Bricksnbeatles said:


> When you say insane amounts of volume, is it just in the high mode? Based on this video (the Preamp Crunch+ *should* be exactly the same as the Celsius, just with a master volume on the output, and a selectable buffer on the input) it seems that in low mode unity should be around 3:00 and in high mode it should be around 9:00.
> 
> 
> 
> ...


Ok, I just watched the full video, that selectable input buffer is interesting.
Here's some of my own findings messing around with different placement in my pedal chain.

The pedal in High mode sounds very different with or without a buffered pedal in front of it.
If I make it the first pedal in my chain it definitely sounds "to me" like a pretty dramatic loss of high end
Or put another way you can look at it as the "maximum sweetening effect" if that's what you what you're looking for.

If I put in the usual "boost" slot in my chain, which is after my compressor with buffered bypass, it's got much more clarity and sparkle to it.

I don't think I have enough room in this pedal for any mods, since I stuck it in a 1590B.

But it if I built it again, I'd do it in a 125B and it would be worth putting in the buffered input mod. You could used one of PPCB's simple jet buffers on a toggle switch. And put a master volume at the output.

After chatting with @PedalPCB he's getting unity at around 25% of the volume sweep. This is what I would have expected.
I need to pull mine apart and see if I didn't use the wrong value pot.

I have a feeling the volume issue on mine is an anomaly and probably something dumb I did.....

Edit: I just looked at the PastFX website and they mention the following:

"*Buffer Circuit*Many owners of the _BOSS_® _CE-1 _noticed that when selecting the high on the input sensitivity switch that some of the high frequencies of their signal was lost. This was a desirable outcome for some. To remedy this, some users would place a buffer before the _BOSS_® _CE-1 _to restore the high frequencies. The _Preamp Crunch_ comes with an inbuilt buffer circuit which can be added or removed as desired."

So I guess my findings are consistent at least with regards to the buffered input.


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## MichaelW (Aug 10, 2022)

Ok update:

*Volume mystery solved! *

And the answer is.................I'm a dumbass.......

@PedalPCB: "You DID use an A50k pot right?
Me: "Of COURSE I did, you think I'm an idiot?????"

Me: (quietly opens the enclosure, takes the board out and sees that in fact it's a B50k in there.....duh......)

With the proper log pot in there it now gets to unity at about 1/4 turn.


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## Robert (Aug 10, 2022)

Niiice, at least it was something simple.


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## MichaelW (Aug 10, 2022)

We're not even going to mention how I destroyed a pad swapping out the pot. And my resulting hack.

Anything I build that needs re-work has only about 50-50 chance of surviving my re-working.......


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## Bricksnbeatles (Aug 10, 2022)

Glad you got it all worked out!


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## MichaelW (Aug 10, 2022)

thewintersoldier said:


> if you are taking a pot out of a board, sacrifice that 50 cent pot and snip all three legs and then go about removing the solder and what's left of each leg. Save the time, effort and pcb and no jumpers necessary.


HAH, I actually did do that, yet still somehow borked the pad removing the pin. I was trying to figure out why the freaking pad wouldn't take solder when I put the new pot in. Then I looked down on my silicon work mat and saw this neat little round silver circle sitting there mocking me.......


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## MichaelW (Aug 10, 2022)

thewintersoldier said:


> what shape tip are you using for desodering? What temp are you running for desoldering? Pump or braid? and are you using additional flux?


Conical tip, same temps that I solder at 715 degrees.  Uber Super Solder Sucker first, then wiggle-wiggle-wiggle applying a little heat with a hemostat on the remaining pot tip from the other side.

Edit: Not that I've done this very often. I think this is maybe only 2nd or 3rd time I've had to yank a pot out.


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## Route14 (Aug 10, 2022)

What are your thoughts on using 1590B enclosures on these smaller projects?


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## MichaelW (Aug 10, 2022)

Route14 said:


> What are your thoughts on using 1590B enclosures on these smaller projects?


I may be the wrong person to ask hahahaha, I really prefer the 1590B and will tend to use them whenever I can shoe horn a build into one. But I may be in the minority here.

There's nothing wrong with a 125B, but I hate seeing the wasted space of a small board in a larger enclosure. It's also gotten me into trouble a few times when I don't measure correctly. Drilling needs to be spot on, lot less margin for error.


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## Robert (Aug 10, 2022)

If one is available for your soldering iron I _highly_ recommend one of these tips for removing pots.

It literally takes about 5 seconds to remove a pot cleanly.  No wick, no solder sucker, no damage to the PCB.


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## MichaelW (Aug 10, 2022)

Robert said:


> If one is available for your soldering iron I _highly_ recommend one of these tips for removing pots.
> 
> It literally takes about 5 seconds to remove a pot cleanly.  No wick, no solder sucker, no damage to the PCB.
> 
> View attachment 30530


I've never even seen one of those. Do you have a link?


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## Robert (Aug 10, 2022)

What soldering station do you have?   

This is the one for my Pace station:


			https://www.tequipment.net/Pace/1130-0501-P1/Tips/
		


Hakko also makes one for the 951 station.


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## Route14 (Aug 10, 2022)

MichaelW said:


> I may be the wrong person to ask hahahaha, I really prefer the 1590B and will tend to use them whenever I can shoe horn a build into one. But I may be in the minority here.
> 
> There's nothing wrong with a 125B, but I hate seeing the wasted space of a small board in a larger enclosure. It's also gotten me into trouble a few times when I don't measure correctly. Drilling needs to be spot on, lot less margin for error.


I prefer the 1590Bs as well and I agree I hate seeing all that wasted space! I recently put a Distortion 250 into a 1590B and side mounted the jacks. I'm going to try top loaded jacks on single pot boards. I've seen you do a few recently and I think they look great!


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## Robert (Aug 10, 2022)

That wide blade makes removing switches just as easy, up to DPDT.

Of course I would never recommend reusing a switch after removing it, although I have a few times for prototypes that are just going into the salvage pile afterwards anyway.

I'm considering getting a pair of blade tips for my tweezers as well, that would make through-hole ICs a breeze to remove.


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## MichaelW (Aug 10, 2022)

Robert said:


> What soldering station do you have?
> 
> This is the one for my Pace station:
> 
> ...


I have a Yihua 939D. It uses Hakko tips. I'll take a look around and see what they have in "big ass blade tips".


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## MichaelW (Aug 10, 2022)

Route14 said:


> I prefer the 1590Bs as well and I agree I hate seeing all that wasted space! I recently put a Distortion 250 into a 1590B and side mounted the jacks. I'm going to try top loaded jacks on single pot boards. I've seen you do a few recently and I think they look great!


This might help.


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## MichaelW (Aug 10, 2022)

Robert said:


> That wide blade makes removing switches just as easy, up to DPDT.
> 
> Of course I would never recommend reusing a switch after removing it, although I have a few times for prototypes that are just going into the salvage pile afterwards anyway.
> 
> I'm considering getting a pair of blade tips for my tweezers as well, that would make through-hole ICs a breeze to remove.


Whoa.....I may need to take out a loan for this one....






						Hakko T31-021402 - Spatula Blade Tip, 750F / 400C - - Amazon.com
					

Hakko T31-021402 - Spatula Blade Tip, 750F / 400C - - Amazon.com



					smile.amazon.com


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## Robert (Aug 10, 2022)

Yeaaah I don't know what's going on there.    It should be less than $100, still expensive for a tip, but $700 is absurd.

You could get the entire solder station with some extra tips for that price.


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## Bricksnbeatles (Aug 10, 2022)

A lot of Amazon sellers will jack the price up on stuff when it’s sold out/unavailable instead of taking the listing down or listing it as “currently unavailable”


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## paulmercer (Sep 6, 2022)

@PedalPCB when will the Build Docs be posted?


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## chongmagic (Sep 6, 2022)

This is much better.



			https://hakkousa.com/products/soldering/soldering-tips/t31-021402-spatula-blade-tip-750-f-400-c.html


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## Robert (Sep 6, 2022)

I went with the narrower 10mm blade so it'd be easier to avoid any adjacent plastic components. 

It'd be easy to destroy something _quick_ with one of these tips.


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## chongmagic (Sep 6, 2022)

Robert said:


> I went with the narrower 10mm blade so it'd be easier to avoid any adjacent plastic components.
> 
> It'd be easy to destroy something _quick_ with one of these tips.





			https://hakkousa.com/products/soldering/soldering-tips/t31-011401-spatula-blade-tip-840-f-450-c.html


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## Robert (Sep 6, 2022)

Yep, that looks similar to the one I have from Pace.

If you remove a lot of pots (or switches, or pin headers) it's definitely worth the money.


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## Bricksnbeatles (Sep 18, 2022)

Hey Michael! Could you measure how far from the top of the enclosure the center of the knob is? I'm trying to finalize my UV print design for this one, and I want to make sure I don't have the pot set too high for the jacks to fit. Gonna be trying out your top-mount 1590B jack instructionsal


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## MichaelW (Sep 18, 2022)

Bricksnbeatles said:


> Hey Michael! Could you measure how far from the top of the enclosure the center of the knob is? I'm trying to finalize my UV print design for this one, and I want to make sure I don't have the pot set too high for the jacks to fit. Gonna be trying out your top-mount 1590B jack instructionsal


I'll do that in the morning.


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## Feral Feline (Sep 19, 2022)

Any snow-shovel type tips for the 888?


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## MichaelW (Sep 19, 2022)

MichaelW said:


> I'll do that in the morning.


It's exactly 1 3/8" from the "top" of the top of a Tayda 1590B enclosure. Don't forget the toggle is in an unconventional place. Check the drill template.


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## Bricksnbeatles (Sep 19, 2022)

MichaelW said:


> It's exactly 1 3/8" from the "top" of the top of a Tayda 1590B enclosure. Don't forget the toggle is in an unconventional place. Check the drill template.


Fantastic, Thanks! 
I’ve got the two holes grouped together so they’ll move together. Now I’ll just move them down so they land in the right spot.


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## Elijah-Baley (Oct 25, 2022)

MichaelW said:


> We're not even going to mention how I destroyed a pad swapping out the pot. And my resulting hack.
> 
> Anything I build that needs re-work has only about 50-50 chance of surviving my re-working.......
> 
> View attachment 30528



We don't have the schematic of this PCB, and I'm trying to understand, looking the PCB draw and this picture, if the resistors value are the same of the original schematic in the CE-1 or there are some adjustment and modify. But it's hard to say. 
Could someone reveal it, please?


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## MichaelW (Oct 25, 2022)

@Robert, you got the Schematic for this in your pile of stuff on your workbench?


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## Elijah-Baley (Oct 26, 2022)

Too see the schematic would be very appreciated!
Meanwhile, I have some concern about the hiss problem with this circuit. At least two users here had this problem, if I don't wrong. Someone built even this stripboard version, too, with the same noise. https://dirtboxlayouts.blogspot.com/2021/01/triungulo-lab-ensemble-crunch.html

The Triangulu Labs and PastFX version seem not suffer any noise problem. And are not the only two CE-1 preamp in a box pedal I found. 

*The One Preamp* https://groberteffects.com/product/the-one-preamp/
*VRM CE-1 Preamp* 



*Lemo & Ginger CEP-1* 



*JFX JF-1 Preamp* 



Here's in raw look, but it's commercialized in better look, too, but I can't identify a brand name 



From the demos I can't hear any noise issue in anyone pedal, nor I can't find any bad review (at least, what we can find about these).

There are some differences in these pedal: peak level LED, High/Low swich mode, buffer in front or not, clipping, volume master... but even in the tone and volume, as I read. Though, I think every circuit is based on the exact preamp circuit. (JFX JF-1 Preamp has just the low mode).


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## music6000 (Oct 26, 2022)

Elijah-Baley said:


> Too see the schematic would be very appreciated!
> Meanwhile, I have some concern about the hiss problem with this circuit. At least two users here had this problem, if I don't wrong. Someone built even this stripboard version, too, with the same noise. https://dirtboxlayouts.blogspot.com/2021/01/triungulo-lab-ensemble-crunch.html
> 
> The Triangulu Labs and PastFX version seem not suffer any noise problem. And are not the only two CE-1 preamp in a box pedal I found.
> ...


 Take note that you can get caught out with the Transistor,  3 different part numbers!:


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## MichaelW (Oct 26, 2022)

@music6000 I used a can 2N222A, are you suggesting this might be the source of the noise? I wonder if it is........hmmmmmm


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## music6000 (Oct 26, 2022)

MichaelW said:


> @music6000 I used a can 2N222A, are you suggesting this might be the source of the noise? I wonder if it is........hmmmmmm



Yes, it should be 2N2222A, your a 2 too short Ha Ha!
Just the Pinout needs to be correct!


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## MichaelW (Oct 26, 2022)

Well crap, I can't remember what I used, you're gonna make me open it up.......heh


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## MichaelW (Oct 26, 2022)

MichaelW said:


> Well crap, I can't remember what I used, you're gonna make me open it up.......heh


Ok I used a 2N222A and the pinout is correct. So its not the source of the noise.


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## MichaelW (Oct 26, 2022)

MichaelW said:


> Ok I used a 2N222A and the pinout is correct. So its not the source of the noise.
> 
> View attachment 34525
> 
> ...


Crap, I just counted my "2's" one isn't accounted for.........DANG IT, did I use the wrong part?

Edit: My bad, the errant "2" was hiding behind the electrolytic cap. I DID use a 2N2222A.


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## Mentaltossflycoon (Oct 26, 2022)

"Why was that other transistor confusing?" "It came down to too many twos too."


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## Elijah-Baley (Oct 27, 2022)

As I said early to see the schematic would be great, but I think that should be just the same schematic we can see in the CE-1 Chorus Ensemble, with one exception.
Looking the PCB here https://www.pedalpcb.com/product/pcb481/ in the MichaelW's PCB C2 is missing, but it seems to me that the ceramic disc moved upper, and is the 470nF cap is taken off, it's the one in front the pin 3 of the IC. It could look weird, but I see other redrawn schematics like that.
Then the TC1044 is for a +9v/-9v.

Maybe I'll attempt to breadboard it if I have all the parts.


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## MichaelW (Oct 27, 2022)

Elijah-Baley said:


> As I said early to see the schematic would be great, but I think that should be just the same schematic we can see in the CE-1 Chorus Ensemble, with one exception.
> Looking the PCB here https://www.pedalpcb.com/product/pcb481/ in the MichaelW's PCB C2 is missing, but it seems to me that the ceramic disc moved upper, and is the 470nF cap is taken off, it's the one in front the pin 3 of the IC. It could look weird, but I see other redrawn schematics like that.
> Then the TC1044 is for a +9v/-9v.
> 
> Maybe I'll attempt to breadboard it if I have all the parts.


Let us know if you figure out what's causing the hiss, this discussion made me take mine out and play it yesterday.
The hiss actually not too bad in clean mode. but once you hit a drive with it, it gets pretty bad. As I said it's a shame since it does lovely things to another overdrive.


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## Elijah-Baley (Oct 27, 2022)

Did you place your pedal before or after the drive pedal? Being a chorus the CE-1 should be after eventually fuzz, drive, etc.
Anyway, I'm working on it.


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## MichaelW (Oct 27, 2022)

Elijah-Baley said:


> Did you place your pedal before or after the drive pedal? Being a chorus the CE-1 should be after eventually fuzz, drive, etc.
> Anyway, I'm working on it.


No, I'm using the Celsius as a "boost/tone conditioner", so before drive pedals.

So here's an interesting tidbit. If you're familiar with Universal Audio product, I use an Apollo Twin X as my recording interface.
UAD makes a LOT of very accurate recording and mixing plugins of classic consoles and studio gear (Neve, etc).

They have less when it comes to specific guitar and bass effect plugins but the ones they have are very very good.

Which brings me to the point....I've been demo'ing the Roland CE-1 Chorus plug in and it sounds fabulous. When they model an amp or pedal they will model it down to the very details of the original, including it's idiosyncrasies (for instance they model the noise of the inherently noisy Friedman DS40 amp)

I was playing around with the CE-1 plug in, and if I defeat the modulation and just use it for the boost part.......guess what?....it makes the same noise....heh.  I would bet if you got your hands on a vintage CE-1 it would probably have the same hiss.

Not to say it can't be improved, just sayin in my opinion, it's an inherent quality of the CE-1.


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## Elijah-Baley (Oct 29, 2022)

I redrawn the CE-1 preamp from the original CE-1 chorus (voltage part is simplified, just to work around on my software).
I try it on breadboard, starting from same basic, I don't know if there's something wrong, because it doesn't work, though the schematic is that.
First of all I excluded for now the transistor stage. Voltage at the pin 7 is 9v, pin 4 to the ground. The Celsius version, I guess, doesn't have C4, so tried with and without it.
Without C4 the circuit is mute. I got over 8v at pin 2, at 9v at pin 6... it seems weird to me.
I tried with a 47nF as C4 (I don't have other 470nF, that was the first I found). Voltage changes, and it sounds very weak, muddy and I got loud crack farting sound at the peak of the strumming. With a 100uF (I know it's big, but without is the same thing). I tried it twice. It doesn't work. 🤨


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## MichaelW (Oct 29, 2022)

Elijah-Baley said:


> I redrawn the CE-1 preamp from the original CE-1 chorus (voltage part is simplified, just to work around on my software).
> I try it on breadboard, starting from same basic, I don't know if there's something wrong, because it doesn't work, though the schematic is that.
> First of all I excluded for now the transistor stage. Voltage at the pin 7 is 9v, pin 4 to the ground. The Celsius version, I guess, doesn't have C4, so tried with and without it.
> Without C4 the circuit is mute. I got over 8v at pin 2, at 9v at pin 6... it seems weird to me.
> I tried with a 47nF as C4 (I don't have other 470nF, that was the first I found). Voltage changes, and it sounds very weak, muddy and I got loud crack farting sound at the peak of the strumming. With a 100uF (I know it's big, but without is the same thing). I tried it twice. It doesn't work. 🤨


OMG, you've invented the much anticipated FART PEDAL!!!


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## Robert (Oct 29, 2022)

Elijah-Baley said:


> I don't know if there's something wrong, because it doesn't work, though the schematic is that.



The circuit runs on a split polarity power supply.

If you're powering it from a single polarity supply you need a VREF bias voltage on the input of the opamp.


I'm working on a solution to the noise issue and also have a couple of the other clones incoming for comparison purposes.

The fix, I believe, will be simple... There's a minor part of the circuit that is commonly overlooked (I am guilty of it).


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## Elijah-Baley (Oct 30, 2022)

I know it was something like that. Well, I have no reason to include the +9v/-9v power supply. I'm sure it will work fine.



MichaelW said:


> OMG, you've invented the much anticipated FART PEDAL!!!


No, really.


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## Elijah-Baley (Nov 3, 2022)

On my breadboard I included the +9v/-9v supply and of course it worked (I was testing just the op-amp section).
I got a lot of volume, and close at highest volume setting I got op-amp clipping (TL071), honestly it's not so nice. My emulator software says it's over 25db, after all.
Even if it changed some circuit characteristic I added a 100k master volume to hear it well ad high gain setting.

Later I included the transistor stage: more volume, it's a a bit dull, it distorts sooner and more, of course. Again, bad distortion, to my hear it sounds fizzy and broken. This circuit seems even very sensible to the pickup position: bridge pickup (in both the guitar I tried) sounds quieter, so less aggressive. (Is it because the breadboard?)
The circuit adds some hiss. It seems to me like a boost at higher gain setting: not so good, but not so bad.

Hearing this circuit like that I don't like it. It's still worth just as clean volume boost, but when it get distortion it's nothing have to do with the mild break up of John Frusciante's sound.

And now I have a question: that bad distortion is it normal? I got something like that in other circuit experiment, and I know op-amp clipping is never so musical. But that nice break up I hear in some demo with this kind of preamp (the various pedals) is due to the tube amp? My amp is a solid state 120w.
I'm not sure because I had no experience with tube amp, unfortunately, but I have the idea that tube amp will go in overdrive at high volume boost of a pedal before the pedal's circuit start to clip. That causes that sweet break up. Instead, solid state amp "accept" all that volume boost keeping the sound cleaner, but then we can hear the pedal start to clip.


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## MichaelW (Dec 16, 2022)

White noise issue fixed! Appended to original post.


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## Bricksnbeatles (Dec 16, 2022)

I’ll probably just order a new board at some point to put in the enclosure I designed for this one, but I may as well give this mod a try too instead of scrapping the board I have rn! Thanks for the heads up


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## Robert (Dec 17, 2022)

Bricksnbeatles said:


> I’ll probably just order a new board at some point to put in the enclosure I designed for this one, but I may as well give this mod a try too instead of scrapping the board I have rn! Thanks for the heads up



Just shoot me a message next time you place an order and I'll send you the new revision.


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