BOSS GE-7 Capacitors

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.
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oetzi1977
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Joined: 14 Mar 2012, 15:15

Post by oetzi1977 »

Hi everyone,
I've purchased an old GE-7 Boss eq and I'd like to mod it a little bit.
My version is the "new pcb" one, with 3 opamps.

I've read that the most important thing due to hiss reduction is to swap the 3 opamps with NE5532, I've found NE5532AP which should do the job: I'm not worried about the current usage 'cos I don't use battery.

The Other Mod that I like to do is to swap 3 1uF electrolytics caps with non polarized ones (C21-C2-C32)

Another mod that I've find is about replacing the caps for the "filter" (or eq) section:
C6 0,1uF
C7 0,15uF
C8 0,33uF
C9 0,68uF
C10 1,5uF

these should all be tantalum caps (in the original layout)
Does it makes sense - for ALL - the caps we talk about to replace with MKT Arcotronics? The small boxed white ones which has 5% tolerance (should be good) made of polyester?
http://www.tekkna.it/product/26614/-1-u ... estere.asp

I've heard many people do these mods usin panasonic stacked metal film ECQ-V, but I can't fin them anywhere.

I know there are tons and tons of topics about that but: once I've read that the differences between materials in caps for stompboxes aren't audible, due to the low voltages in the circuits.

Many Thanks!

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rockhorst
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Post by rockhorst »

Panasonic ECQ-V has been out of production for a few years. You can still find them but it requires a bit of digging for certain values. In any case, other type of film caps should be fine.

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microbailey
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Post by microbailey »

Just to add that for a graphic EQ pedal like the GE-7 the most important thing (IMHO) is to get the replacement caps to match the original designed values since the filters are tuned to specific freqs and if the caps are off those bands will move and the pedal will sound different to intended. So you'll want low tolerance caps which have good stability over temp etc.
Of course that goes for the resistors too.
"There's something about a Gucci loafer kicking on a fuzz pedal" Alex Turner, Arctic Monkeys

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oetzi1977
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Post by oetzi1977 »

Thank you so much for the answer!

I was just wandering why so many people talks about "recap" some pedals (ge-7 seems to be one of the most "recapped" ones), swapping some polyester caps (the transparent ones that you can see into many boss pedals) with other polyester caps! (for example: arcotronics MKT).

I mean: can a real difference in sound be heared? I've read some articles telling that due to the low voltages in guitar stompboxes the "sound" of a polyester cap compared to a Stacked-metal-film Panasonic can't be heard.

Many people replace the tantalum filter caps with WIMA, Panasonic, etc... but I'd really like to hear a side-by-side comparison between a GE-7 with high grade super mojo hi-fi caps and another one with MKT white box polyester one that costs half the price! :D

It's right to pay attention - for example - to tolerances, and I always prefer to use "j" caps instead of "k", if I can Choose. :thumbsup

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