BOSS CE-2: clock frequencies (and maybe more)

Started by Thomeeque, January 03, 2011, 07:23:12 PM

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Thomeeque

 Hi!

My first post this year so PF2o11! :)

Now, I have built my (bit simplified) version of EHX Small Clone - it works well but after few days of playing with it I did found that I actually don't like this particular kind of chorus very much (it's not my build's issue, I did watch reviews of original Small Clone, Nano Clone and MXR Micro Chorus lately and it's the same there..) - what I miss there mostly is this light sweet chorus sound of CE-2 with both pots around the noon (like here). So I have decided to try to tweak my build to get closer to CE-2 character.

First I should probably get to the same delay (clock frequencies) range - unfortunately when I have tried to find some details about clock frequencies/delay times used by CE-2 on-line I did not succeed (even service manual does not mention it). Does any of you guys know some details? Or would you be willing to do some measurements for me (if you have CE-2 /or clone/ and oscilloscope or frequency meter), it should not be complicated..? :icon_redface:

Thanks, T.

Btw. I have tried to emulate CE-2's LFO+clock circuitry (LFO by LTC, clock on breadboard using CD4049 instead of MN3101), this is what I have got:



(for middle depth swings Vctrl between 3 and 6 Volts, so it makes 8.4 ~ 11.6ms delay range)

It looks reasonable, but it may be wrong (I have used only roughly matching diodes, transistors and invertors, it's messy etc.) so I'd use some confirmation.

Note: fclk would be yet divided (by 2) at MN3101 outputs.
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oldschoolanalog

#1
As far as chorus sounds/tones go, this totally blows away all the chorus f/x you mentioned.
Close to home too! ;)
Use those MN3007's for something more interesting!
Mystery lounge. No tables, chairs or waiters here. In fact, we're all quite alone.

Thomeeque

Quote from: oldschoolanalog on January 03, 2011, 09:09:58 PM
As far as chorus sounds/tones go, this totally blows away all the chorus f/x you mentioned.

Oh Dave, you can't do this to such a modest guy as I am, such amount of pride will ruin my karma!! :icon_redface: But I must agree actually! :icon_mrgreen: I really love chorussy sounds I'm getting out of EM1022 a lot! Thing is that I'm building something bigger (modulation multi-fx) and I want to have both chorus and flanger as two individual fx's there to be able to (foot)switch them in the middle of the song.. Well, two EM1022's would be ultimate solution ;), but I don't want to give up original idea yet :)

Quote from: oldschoolanalog on January 03, 2011, 09:09:58 PM
Close to home too! ;)

:)

Quote from: oldschoolanalog on January 03, 2011, 09:09:58 PM
Use those MN3007's for something more interesting!

Sure sure, I'm using 3207 for this (CD3207GP to be precise)..

Cheers, T.
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Morocotopo

Tomas, that´s outstanding! Very nice pedal! Lots of variety!
Never heard of the TDA1022 chip. Is it available?
Morocotopo

Thomeeque

#4
Quote from: Morocotopo on January 04, 2011, 12:38:55 PM
Tomas, that´s outstanding! Very nice pedal! Lots of variety!

Hi Ariel, thanks, I'm glad you like it! There's a thread practically dedicated to the EM1022 pedal: http://www.diystompboxes.com/smfforum/index.php?topic=74867.0 - if you have any question about it, hit it there.

Quote from: Morocotopo on January 04, 2011, 12:38:55 PM
Never heard of the TDA1022 chip. Is it available?

TDA1022 is pretty hard to get unfortunately, but juancra was able to get them somewhere and he's from Argentina as well (!!), so maybe you'll be lucky..?

T.
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Thomeeque

#5
 C'mon, guys, nobody is willing to help? :-\

At least one and only measurement:

  • set DEPTH pot to it's minimum (there should be no modulation and clock should be frozen at middle point of sweep) and
  • measure frequency at pin 2 or 6 of MN3007 (or pin 2 or 4 of MN3101) - that's it..

And if I *may* ask for more:

  • set DEPTH pot to the middle (noon) position,
  • set SPEED pot at minimum and
  • measure lowest and highest frequency at pin 2 or 6 of MN3007 (or pin 2 or 4 of MN3101) - even very roughly, I don't need precise values

Pleeeaaase!

Thanks, T.
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Fender3D

One just arrived for repairing...
DEPTH=0 ~110KHz
DEPTH middle from 100KHz to 128KHz
@pin 2-6 MN3007
"NOT FLAMMABLE" is not a challenge

Thomeeque

Quote from: Fender3D on January 05, 2011, 11:28:33 AM
One just arrived for repairing...
DEPTH=0 ~110KHz
DEPTH middle from 100KHz to 128KHz
@pin 2-6 MN3007

Fantastic! Thanks a lot, Federico!  :-* ;D
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