Big Muff Opamp

[LordSven]

here is a small vid of the pedal, played through a vox valvetronix AD15VT (Black 2x12 modelisation) and a Fender Stratocaster MIM 1998. Actually on video it sounds quite good  Ican post another video with my Ram's Head and OP amp Big Muff (build with a PCB bought on Aliexpress)

[LordSven]

here with a Ram's Head (coda Effects PCB) and then a OPamp version with a PCB bought on aliexpress which sounds not too bad to my tastes 

[stringsthings]

C2, the capacitor below the 4558, should be 10nF.  You've got a 100nF.
I believe this results in a fair amount of high end loss and perhaps some distortion since you're
bleeding more low frequencies to ground, which lowers the overall signal level feeding the sustain pot
and the 741.

I would also double-check C9, which should be 120nF.
It's the green cap near the volume pot connections.

[LordSven]

C2, the capacitor below the 4558, should be 10nF.  You've got a 100nF.
I believe this results in a fair amount of high end loss and perhaps some distortion since you're
bleeding more low frequencies to ground, which lowers the overall signal level feeding the sustain pot
and the 741.

I would also double-check C9, which should be 120nF.
It's the green cap near the volume pot connections.

yessss !!! thanks i did a mistake doing the conversion when choosing the C2 cap, i took a 100n instead of the 10n, I've just changed it and now that's way much better  Next time i will be more careful. The c9 cap was ok (120n) That's great, that's how we move on  i suppose
Tomorrow I will prepare the box and transplant the guts inside  Thanks to everyone for your help, I love that forum

[bloxstompboxes]

That's great man! That board's looking pretty good too. Don't forget, gut shots and and enclosure pics are mandatory here, lol.

[LordSven]

That's great man! That board's looking pretty good too. Don't forget, gut shots and and enclosure pics are mandatory here, lol.

thanks to you Eric, your PCB's great, I love that pedal now  I'll put some pictures as soon as the finished box will be ready, I'll try some decal on a  silver 1590BB. Next builds are small stone, Big Muff green Russian and Triangle and then Superfuzz 

[stringsthings]

Glad you got it working!  The op amp BMP is one of my all-time favorite stompboxes.
Way back in the late 70's, I bought a brand new BMP deluxe which has the op amp version.
So my ears prefer that version.

It wasn't until many, many years later, that I found out the original BMP used 4 transistors.

[LordSven]

Glad you got it working!  The op amp BMP is one of my all-time favorite stompboxes.
Way back in the late 70's, I bought a brand new BMP deluxe which has the op amp version.
So my ears prefer that version.

It wasn't until many, many years later, that I found out the original BMP used 4 transistors.

Yes it's a great sound to my ears too. The only original Big Muff I've tried or owned is the V9 reissue which sounds not bad too but with less clarity. My favourites until now are the Op-Amp and the Ram's Head. I can't afford vintage ones so I have to build them and this has become a great hobby. Has anyone here build a Deluxe Big Muff (the vintage one with the onboard compressor ) ?

[stringsthings]

Has anyone here build a Deluxe Big Muff (the vintage one with the onboard compressor ) ?

The Deluxe BMP had a compressor that was similar to the old soul preacher, I think.  It was a really noisy compressor
with a super heavy squish.  The opposite of transparent.  Again, since that was my first experience with a compressor,
I actually like that sound.  I haven't been able to successfully clone that version of the soul preacher.  I think aion electronics was thinking about doing
a Deluxe BMP clone.

[LordSven]

Has anyone here build a Deluxe Big Muff (the vintage one with the onboard compressor ) ?

The Deluxe BMP had a compressor that was similar to the old soul preacher, I think.  It was a really noisy compressor
with a super heavy squish.  The opposite of transparent.  Again, since that was my first experience with a compressor,
I actually like that sound.  I haven't been able to successfully clone that version of the soul preacher.  I think aion electronics was thinking about doing
a Deluxe BMP clone.

very interesting news , i'll check their website and will buy the PCB if they do it. By the way i've discovered this yesterday on facebook :
https://fxtransposednet.bigcartel.com/product/big-muff-project-development-pcb-for-diy-and-learning-pre-order

sounds interesting too 

[LordSven]

Hi everyone, here are a few pictures of the finished pedal. I had to wait for my decals order to finish the building of this great Big Muff OP-amp. I messed up when drilling for the AC... but all works fine, the sound's great, I play it with a stratocaster with single coils in a Vox AD15VT valvetronix amp (at home) or through a Fender Deluxe Reverb 65 RI to practise with my band. I gotta change the knobs for black ones similar to those on big muffs. I chose to stay close to Electro Harmonix design becaue i like it this way....
I gotta improve to have a tidier inside but once it's closed noone sees it and it's not for my personal use not for sale....Thanks to all of you who helped me for this project...Not the last one 

[stringsthings]

Nice build. It's hard to beat those classic EHX styles.

Your wiring will get neater with future builds.  You should see some of my older builds.
I would post pics but I don't want anyone to faint. ( or pass out from laughing too hard )

[bloxstompboxes]

Good job Bro!

[LordSven]

thank you I'm fully motivated because of you and this great forum 

[LordSven]

the big Muff family so far...