TREMMY TREMOLO

[bluebunny]

ok, got my 2 lfo's going...

Blimey!  Get thee to a synth forum!      Then let us know where you land and we'll all follow.   

[deadastronaut]

^ funny, i have been looking at a load of synth stuff lately.....inevitable i guess.


anyway, swapped the lfo's over...clip.

https://dl.dropboxusercontent.com/u/7464107/filtertremmy9.mp3

i quite like the filter, but i may as well just stick a phaser/ms20/flanger after it and be done with it  really...good fun though..

[John Lyons]

Nice work Rob, it sounds fantastic.

[bluebunny]

^ funny, i have been looking at a load of synth stuff lately.....inevitable i guess.

Ha ha - yeah, me too!      Knowing my unstoppable GAS, I feel a visit over to Rick's emporium to pick up some modules is inevitable...   

[haveyouseenhim]

^ funny, i have been looking at a load of synth stuff lately.....inevitable i guess.

Ha ha - yeah, me too!      Knowing my unstoppable GAS, I feel a visit over to Rick's emporium to pick up some modules is inevitable...   

Don't forget the two year shipping time...                     

[deadastronaut]

cheers john:

@mike...now now..you know these things take time...


i stuck a keyboard through this too last night...pretty cool, especially on pads, drones etc...

[bluebunny]

i stuck a keyboard through this too last night...pretty cool, especially on pads, drones etc...

Damn your eyes, Rob!  Now I'll have to build one of these into a Eurorack module!                                                            

[nocentelli]

Sounds great, beautiful playing too. So is it tremolo->filter? Any chance of posting the schem from that lsst clip?

[deadastronaut]

hi leo, its basically this:

http://www.diystompboxes.com/smfforum/index.php?topic=107197.msg975196#msg975196

with 2 of these lfo's.(bottom schemo) ..but only one lfo has the square/triangle switching...which is for the trem side of things....other lfo for filter..

http://www.diystompboxes.com/smfforum/index.php?topic=107197.msg975091#msg975091

[deadastronaut]

had to move the filter on off switch to the pin 1 side of the opamp, otherwise i get  bleed through when off...(note to self really )

i'm tweaking the filter to be at a better 'unity' tonal wise when using distortion...its all fine when clean, but adding distortion is a little lower really...tweak tweak..

i also had it working just as well with removing the top 'T' entirely... so it was just the 470k and 2x 2.2nf's>ldr..

[deadastronaut]

ok, had a few tweaks here n there....

mainly i found using super green led for the ldrs gave the best sweeps...and used yellow diffused for the indicators to avoid blindness..(which work together nicely)

i also removed the upper/lower half of the twin t filter, which gives me a fuller filter sound which goes much better with a distortion,

i added a pot there instead which gives me a depth/Q control too..very cool. and adjusted the lfo to suit..

like i said i shifted the filter swtch to the right (pin1) of the opamp, otherwise i had bleed through when off....behaves nicely now...

i still hate the trem depth control though, ive tried sticking a 1k across the 1k pot, and reversing the pot  but its still bunched up....needs attention imo..



this is where i am so far,

[bluebunny]

Another cool project.  Nice one, Rob.  

. . .used yellow diffused for the indicators to avoid blindness

Unlike this one of mine!  

[deadastronaut]

^ funny i just got an appointment letter from specsavers...must be an omen.

[duck_arse]

hey rob.

something to try led driving wise. remove R25 (Anode now to pin 7), shift the pin 6 wire to top of R24, maybe increase R24. this may blow everything up, I dunno, worth a try if you're still on the bb. the driving method is working for my envelope this end.

and the green led on the depth pot: is that ON - going OFF-er with the lfo, or is it OFF- turned on-er by lfo?

[deadastronaut]

cheers DA,  ive had a few tweaks , ok got the freq's sorted on the filter with distortion....this is twiddling with the filter/ldr Q pot.

still need to sort the depth out without altering the freq though....little steps...

i'm having a hawkwind flashback morning...(with the choppy trem added you can get a great spirit of the age thing going..really authentic sound)


https://dl.dropboxusercontent.com/u/7464107/tremshifterQ.mp3

[bluebunny]

i'm having a hawkwind flashback morning...

"The Hawkwind".  That's what I'll be calling mine, when I build it...   

[deadastronaut]

that's the spirit.....erm.....of the age..

coats on...

but before i step outside, i was thinking...yeah i know right

but as i'm switching this filter in/out, i may as wel be a greedy little bugger and  switch between 2 filters too...bright/warmer - thin/fat..

on/off/on switch may as well while i'm at it..only a couple more bits

[bluebunny]

Next, you'll be wanting a third LFO to morph between two filters.

Oh no!  What have I said?!   

[samhay]

Sounds cool Rob.

^still need to sort the depth out without altering the freq though.
At the moment, as you turn down the depth, you shift the filter towards the treble.
Try putting a C100k depth pot in series with the 2n2 caps in the filter. As you add resistance, you reduce the peak and add a shelf, which flattens it out.

Edit - and I would imagine the filter might sound fuller with 4n7 caps insteady of 2n2.

[deadastronaut]

cheers sam, yep i tried that last night with a 100k (trim) i haven't got a C POT though..

it works, but i get a whooooshhhhh over the top still too...(which may be unavoidable with a dirt pedal on it i guess )


edit: yeah i tried different caps, fatter/thinner, that's what i was saying about switching them too...