Boss CS-3 mods

[chris1001]

Hi,

I've been checking out a few of the Boss CS-3 mods that are floating around the internet, one of the more popular ones, the Monte mod, says to change D1 from a 1N4004 to a 1N34A germanium, but from what I can see this diode can have no effect on the sound processing aspect of the circuit at its conencted to the power 'in' and is probably there to protect the circuit from a reverse polarity connection? Or am I totally wrong?!

ANy help or info greatly appreciated,

Thanks,
Chris

[Sava]

Try replace D6 with Ge diode 1N60, 1N34 etc.

[beatstrat]

Nice job, Chris - another lesson in the hype of bogus pedal 'mods'.

Forum member wampcat (or wampcat1 or something, hell I don't rem) has some actually usable modifications for this circuit - others may as well, but I haven't seen those.

Contact him for more info.

[96ecss]

Hi,

What does Monte "claim" replacing D1 with a Germ will do? You could always replace it and see if you hear the difference. It doesn't seem like it would make any difference to me either.

Dave

[Sava]

Hi all,
Boss CS-3 my modes:

Sava Mod ONE
----------------------------------------------------------------------
Location   Stock val   Sava mod   Type

C2            0.022            0.047             Metal film PE
C15           0.047           0.047            Metal film PE
C13           0.047           0.047            Metal film PE
C4            1 microF      1 microF        Tantal
C14           1 microF      1 microF        Tantal
C18           1 microF      1 microF        Tantal
C6            1 microF      1 microF        Tantal
C5            560 pF           560 pF           Silver Mica
C7            0.01             0.01              Metal film PE
C8            0.01            0.01              Metal film PE
D6            Si uni            1N60,1N34...  Germanium
C1 (under pot)    0.027            0.027         Metal film PE

Option 1:
LED            red             blue               3 mm
R33            3k3             2k2              Metal film

Option 2:
C7            0.01            0.047        Metal film PE
C8            0.01            0.047        Metal film PE

I prefer mode with 0.01 microfarad C7, C8. Clear and transparent mode.
Capacitors must be high-quality.

Sava Mod TWO
----------------------------------------------------------------------
Location     Stock value   Sava mod       Type

C2          0.022                 0.1                Metal film PE
C15          0.047                0.1             Metal film PE
C13          0.047                0.1             Metal film PE
C4          1 microF        1 microF        Tantal
C14          1 microF       1 microF       Tantal
C18          1 microF       1 microF       Tantal
C6          1 microF        1 microF        Tantal
C5          560 pF                560 pF          Silver Mica
C7          0.01                 0.01              Metal film PE
C8          0.01                 0.01              Metal film PE
D6          Si uni                1N60,1N34...       Germanium
D2          Si uni                1N60,1N34...       Germanium
D3          Si uni                 1N60,1N34...    Germanium
C1 (under pot) 0.027           0.027               Metal film PE
R36          10 Kohma           4,7 Kohma    Metal film

Option 1:
LED          red                blue             3 mm
R33          3k3               2k2                     Metal film

Option 2:
C7          0.01               0.047            Metal film PE
C8          0.01               0.047            Metal film PE

More bass mode.

[SilverSurfer]

To All CS-3 Users,

I bought one used and I noticed there is some background noises and it seems to go up when the sustain knob is turned up, is this normal?  I would expect it to be totally quiet.  Also, at first the light would shine 1/2 as bright when plugged to a power plug, but with a battery it shines fully bright, any suggestions.

Mike

[searoad]

To All CS-3 Users,
I bought one used and I noticed there is some background noises and it seems to go up when the sustain knob is turned up, is this normal?  I would expect it to be totally quiet.  Also, at first the light would shine 1/2 as bright when plugged to a power plug, but with a battery it shines fully bright, any suggestions.
Mike

1.the sustain also increase gain so i think it is normal.
2.check the label beside the dc jack. if it requires an ASA adapter, there is some rectifier devices(one diode and one resistor iirc) u need to short out to get the same voltage to the circuit as the battery powers.

[SilverSurfer]

thanks

[SilverSurfer]

Has anyone tried converting the dip 8 to a 8-pin opamp?  I saw a conversion board on monte allums website.  I want to try this out on my ds-1 and cs-3.  I hope to eliminate the sustain hiss on the cs-3.  The ds-1 kit from his website sounds great.  I like the led mod in the distortion circuit.  Nice big fat sound.

Mike

[PerroGrande]

The board from Monte Allums looks to be a bit more elegant than the method I resorted to recently...   



To explain... 

This is only a temporary condition for this CS-3.  A friend's pedal died recently and made it to my bench for repairs.  The CS-3 uses 1/2 of one of the 4558's to produce the 4.5v Vref for the rest of the pedal, and that is the half that died.  I was out of the SIP version of the op-amp, but wanted to test to see if any other part of the pedal needed work (and a part I was also out of...)  So I straightened 4 of the 8 leads on this unfortunate op-amp (an HA-17358) and wire-wrapped the others for testing.  Fortunately, the op-amp was the only thing fried...  While this technique worked for testing, I wouldn't advise it when you're actually trying to *improve* the sound of the pedal!   

[Mark Hammer]

What in heaven's name is up with those three caps?  They look like pustules or something.  Is that goop on top, or goop leaking out?

[nooneknows]

Mine has it too, something like hot glue (what is its name in english?) connecting the three caps together; in the picture the caps are divided.
Marcello

(BTW, I was just looking around in the web searching for CS-3 mods...)

[SilverSurfer]

To Perro Grande

Is IC1 the chip you replace in order to get rid of the noise?  I notice there are a few on the CS-3 board.

thanks

Mike

[ianmgull]

I just recently finished the Monte Allums Opto Plus mod myself. I ran into the same problem with the LED being really dim. If you do have the older ACA version you simply need to remove Resistor 32 and Diode 10 and put jumpers in their place.

All and all I was happy with the mod, although there is still a lot of noise with the tone and sustain knobs maxed.

[wampcat1]

schematic:
http://www.indyguitarist.com/schematics/boss/cs3-compressor.gif

Add a cap in parallel with c4. try 100pf -500pf for noise. Do the same for the resistor across pins 2 and 3 on IC4A (R16 maybe?)

bw

[SilverSurfer]

To Brian,
Thanks for the suggestions.  I actually have a couple of your books and pulled out the CS-3 mods.  I'm going to try a few.

To Ianmgull,  What IC chip did you relace in the opto mod plus.  I have the instructions for the opto mod, but not the one with the swap of the dip8 chip.

Thanks

Mike

[PerroGrande]

Hi Mike,

The chip I installed was temporary, and was only done to validate that the pedal worked otherwise.  The original fault caused the 4.5v VRef to not be present.  If anything, the temporary chip I put in was worse in terms of most specs than the original.

The "cap goop" is glue.  Why they felt the need to glue those caps together is somewhat of a mystery to me.  I removed some of it so I could move them a bit to create more work room around the chip.

[ianmgull]

To Brian,
Thanks for the suggestions.  I actually have a couple of your books and pulled out the CS-3 mods.  I'm going to try a few.

To Ianmgull,  What IC chip did you relace in the opto mod plus.  I have the instructions for the opto mod, but not the one with the swap of the dip8 chip.

Thanks

Mike

The mod kit came with a OPA2134PA chip. I'm not going to knock the mod kit. It definitely helped a lot, but there is still more noise than I would have liked.


Wampcat1:

I'm interested in the mods you suggested, but I'm a serious noob so I'm curious...Have you tried either of these?

[wampcat1]

To Brian,
Thanks for the suggestions.  I actually have a couple of your books and pulled out the CS-3 mods.  I'm going to try a few.

To Ianmgull,  What IC chip did you relace in the opto mod plus.  I have the instructions for the opto mod, but not the one with the swap of the dip8 chip.

Thanks

Mike

The mod kit came with a OPA2134PA chip. I'm not going to knock the mod kit. It definitely helped a lot, but there is still more noise than I would have liked.


Wampcat1:

I'm interested in the mods you suggested, but I'm a serious noob so I'm curious...Have you tried either of these?

Adding the caps as I posted above? No, as I don't run my compression high enough to warrant worrying about. However, there are only so many ways to skin a cat. That's one of them.
bw

[beatstrat]

(somewhat OT)

Have you seen the 'inline > DIP' chip adapter on Allums' site?  Maybe marketing/hype crazy/overkill, but unique (or, maybe not unique - but I hadn't seen one prior to this).

http://www.monteallums.com/pedal_mods.html  Scroll down a bit to see one here.