Boss GE-7 Mods

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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alteredsounds
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Post by alteredsounds »

There's a few people offering mods for this eq, I dont own one but wondered what kind of thigs they were 'fixing'? higher spec parts? value changes?

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bajaman
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Post by bajaman »

probably adding snake oil and thermal flux capacitors and thyristragons - all of these make it a better sounding hiss machine :wink:
bajaman

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alteredsounds
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Post by alteredsounds »

bajaman wrote:probably adding snake oil and thermal flux capacitors and thyristragons - all of these make it a better sounding hiss machine :wink:
bajaman
yep, quite sure that's what 99% of these mods add, i'll never buy one but always interested as to what exactly they are offering

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MartyM
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Post by MartyM »

I posted a set of mods on arons forum, no snake oil either !!
The stock unit creates "hiss" when you turn DOWN the two lowest freq controls !! - try it - unbelievable
The problem was mostly the crap tantalum caps attached to each tone band.
Swopping them out for decent poly caps helps a LOT as does changing three IC's from Tl022's to tl072's.
The set of mods I posted was available within a week on ebay !!
Oh well .... whatever ....

MM.

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bajaman
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Post by bajaman »

Hi Martin
Nice to see you made it here to the AOF :lol: shhhhh :wink:
Some very good points and observations made by you as usual :)
thanks for your input and welcome to freestompboxes.org
cheers
bajaman

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bajaman
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Post by bajaman »

Hi again Martin
What part of London do you live in - I was originally a womble from Wimbledon, many, many years ago :lol: Left the UK with my parents 48 years ago, but still have fond childhood memories ( before the dreaded motorway) walking on Wimbledon Common and Richmond park etc.
Cheers
Steve

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MartyM
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Post by MartyM »

bajaman wrote:Hi again Martin
What part of London do you live in - I was originally a womble from Wimbledon, many, many years ago :lol: Left the UK with my parents 48 years ago, but still have fond childhood memories ( before the dreaded motorway) walking on Wimbledon Common and Richmond park etc.
Cheers
Steve
I live a stones throw from Twickenham Rubgy ground !
Moved here from Widnes, Cheshire when i was 17 ... with a band !
Have been gigging/recording and causing a general nuisence ever since.
Thanks for the kind welcome, I'll try to contribute whenever possible, I hope
it wont all be "fluff and nonsense" ! :roll:

Marty.

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roseblood11
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Post by roseblood11 »

Hi,

-replace the three JRC022D with RC4559P
(NE5532AP, OPA 2134, OPA2132 or OPA2604 should work as well and maybe even sound better, but the 4559 is a good and cheap choice here - it´s most important to replace the NJM2068 with a high quality, low noise chip, see below...)

-replace capacitors:
C18,C25, C29, C30 : 0.047 µF
C21, C22, C32 : 1 µF
C13 : 0.1 µF
(use stacked metal film caps (MKT) for all positions!!! Panasonic ECQ-V series sounds very good here)

-Replace NJM2068 at position IC3 with a OPA2134 (use a DIP-SIL-Adapter or built an adapter using perfboard). (Look at the photo below)
DIP-SIL-adapter: http://www.musikding.de/product_info.ph ... --SIL.html (you can buy them from Monte Allums, I guess)


These mods only work with the new version of the GE-7, which looks like this:
http://www.monteallums.com/images/GE7_New.jpg


Image


Immo

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nooneknows
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Post by nooneknows »

I've changed caps and ic (to tl072 and I can confirm almost all of the hiss has gone. Plus it seems a bit more 'musical', but this one could be only a psychoacoustic effect...

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roseblood11
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Post by roseblood11 »

It´s more than just a psychoacoustic effect if you chose other IC´s. The TL072 isn´t much better than the original ones... If you don´t wanna spend the money for a OPA2134, try NE5532AP (the "A" is important!).

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Post by nooneknows »

I didn't use ne5532 for their high current consumption, I used to rely on batteries in the past. Maybe it's about time to think again about that chip, now that I always use power supplies.
thank you

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Post by devastator »

HI,

Soemone knows what's the "sniper mod" ? everytime I google "boss ge7 mods" I find that mod without knowing what is it.

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Post by cctsim »

devastator wrote:HI,

Soemone knows what's the "sniper mod" ? everytime I google "boss ge7 mods" I find that mod without knowing what is it.
IC1, IC2, IC3 -> RC4559p
C23 -> 270 pF (Silver Mica)
C21, C22, C32 -> 1 uF Panasonic stacked metal film
BLUE LED + resistor to adjust brightness

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Post by devastator »

thanks

So I did this mod too :lol:

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Post by sinner »

I'm sorry to bump the oldy up, but I've just trade dead GE7 for a beer. It was quiet as an mouse, no signal at all. After I've open it up, I've noticed that someone tried to performance some mods with this unit. All opamps ware desoldered, sockets ware installed, and the old IC back on place. The problem was soldering bridge under IC sockeds, and one of the IC was fried. Now its working, I'm glad that there is some noobs on this planet bigger than I am myself. But I'm still noob after all, so I'm asking, have you got something for me to improve it? Make it quieter?

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Post by RnFR »

i've got one of these older versions sitting on a shelf as well. i'd be interested to know anything i could do with it as well. maybe i'll try switching out those tants.
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roseblood11
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Post by roseblood11 »

The circuit is very similar to the newer versions. Try to do the mods that I described above - it´s really a great improvement!

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Post by sinner »

Thanks, I'll do what you suggest. Plus I'll change all electrolytic to panasonic ones I have somewhere, as they can become noisy with time. I think R.G. Keen is the one who says they need to be changed every 10 years in amp, so this rule should apply to FX's as well...

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dfer
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Post by dfer »

Is there any point in upgrading IC4 on the new GE-7? Is it in the signal path? Does anyone have the newer GE-7 schematic i only got the old one :(


And besides these caps - C18,C25, C29, C30 : 0.047 µF
C21, C22, C32 : 1 µF
C13 : 0.1 µF

Is there any other caps to replace in the signal path?

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