Boss CH-1 Super Chorus Mod?

[WretchedSwarm]

Hey everyone; im a new member and I really hope this board can help me out with my effects questions and dreams.

I have a Boss CH-1 Super Chorus Pedal made in Taiwan that I bought used on Ebay. This pedal sounds good straight from the factory; but it sounds a bit too thin and empty when youre trying to get the deeper more watery chorus youd expect from a near 100 dollar pedal. I was wondering if anyone knew any kindof of mods or repairs that can be made to this baby to make it really come to life and play with a bit more color and fullness. Something that could possibly make it like an ElectroHarmonix Small Clone with a better EQ and Level selection? Help me out if you can! Thanks!!!

[Mark Hammer]

Mods to a chorus?  Hmmm.  can't think of any off the top of my head.  Never seen any either.

Sorry, couldn't resist!

[delbowski]

hi...

welcome to the forum!

if you're looking for mods on a CH-1 i'd recommend you check out

http://www.guitartone.net/

click on "how to modify your own effects pedals" from the menu on the right.  Brian has a book that comes either hard copy or paperback that gives you a ton of mods for lots of pedals.  you can also order mods for just one pedal if you'd like also.  he's a really good guy and is a ton of help!  if you wanna hear what his mod will do check it out here...

http://www.indyguitarist.com/mods.htm

get in touch with him and i'm sure he'd love to talk to you...

the other thing you could try is to use the search function and see if anyone has posted threads that deal with this topic... never know what you'll find and it's a safe bet that you'll learn something new as well!  hope this helps...

welcome!
del

[Mark Hammer]

Sorry to jerk you around like that.  After such a lengthy ongoing debate over the proposed mods database, I just had to do something like that.  Sometimes, in the bowling lane of life, when people set the pins up so neatly, you just have to knock them over.

Okay, seriously.  Small changes to the time-delay range of a chorus can make a big difference to the feel of the sound produced.  Move the overall range of sweep up or down by 2msec and one player says its crap while another exclaims "Finally!  That's the sound I was looking for".  In both instances, the delay range falls within what can be called the category "chorus".  No single delay range is correct or incorrect, and different companies aim for different ranges just to carve out a niche for themselves in the market.

Altering the delay range is, happily, pretty easy to do.  You will see on the board a chip labelled MN3101.  This is the chip that generates the clock signal that steps the delay chip through its paces.  Snuggled up beside it somewhere will be a small value capacitor, in this case a 47pf cap.  Making that cap larger in value will increase the amount of delay time produced, and decreasing shortens the delay time.  Shortening it moves it closer towards flanging (though never quite) and increasing delay moves you towards those spacey Pat Metheny sounds.  Given that the stock value is 47pf, I would not make it any less than 33pf, nor any higher than 68pf or perhaps 75pf. 

Note that increasing the delay time will increase the degree of "wobble" produced by the unit.  You will find yourself opting for lower depth settings than you are accustomed to.  That is an inherent aspect of making this minor change.

And welcome.

[vanhansen]

I've got a couple on my site, http://diy.erikhansen.net, thanks to the help of Mr. Hammer here.    I especially like the delay range mod.

[mrsmith]

Hi, I'm new to the forum and modifying guitar pedals. I want to modify my CH-1--not really much of an effect, as far as I'm concerned--and I had a question about the IC's for the mod. In the Wampler book on modifying this pedal, he doesn't mention changing the the IC's; however, the Monte Allums site has two IC's switched out in their kit. Does changing these IC's matter? If so, which ones would I change in the circuit and to which values? Thanks!

Mike

[GGBB]

Hi, I'm new to the forum and modifying guitar pedals. I want to modify my CH-1--not really much of an effect, as far as I'm concerned--and I had a question about the IC's for the mod. In the Wampler book on modifying this pedal, he doesn't mention changing the the IC's; however, the Monte Allums site has two IC's switched out in their kit. Does changing these IC's matter? If so, which ones would I change in the circuit and to which values? Thanks!

Mike

"Matter" is pretty subjective and totally dependent on what you are after sound-wise.  Monte obviously believes they make a difference.  You can change any of the ICs except for the MN3007 and MN3101.  Monte's IC mod looks to be replacing only one IC with two different ICs stacked together (operating in parallel).  Not sure which IC he changes but I doubt it's the M5223L since it isn't in the signal chain.  You will need to make sure that the replacements have the same pin-out and will handle the same power supply (which shouldn't be a problem).  Pin-out is the issue since the existing ones are 8-pin inline which is odd nowadays.  Monte provides two DIP chips on an adapter board.  I think he also sells the adapter boards separately and his prices are reasonable.  Changes to the ICs probably won't make much of a sonic difference except for perhaps noise and distortion levels - as Monte himself says "The Dual Chip Adapter will add clarity and presence and clean the circuit up" - so unless you find your CH-1 too noisy or lacking "clarity", you may not find value in the changes.

I bought his mod for a CS-3 and it made an improvement, so I can vouch for at least one of his offerings.  It had the same IC upgrade and yes - it was cleaner and clearer - a bit.

[Rob Strand]

Change the filters to be more like CS-9 or CE-2 (if you like those more).