"Modular effect" noise problem

[j.frad]

Hi!
I've just finished building and effect based on these modules:
-a bass paralooper to blend with clean signals
-a vanishing point type of 8 step sequencer (velleman led kit that does the same thing)
-tremulous lune LFO
-Dr who "ring modulator"
-neutron filter

I use the LFO and sequencer to drive led which change the value of LDRs in the Dr Who and filter. And it gives me some grat crazy sounds!

I haven't done any filtering yet, running it off a 9v battery, all modules have a common +9v and a common ground (including audio), the LFO and sequencer don't tick but I get massive hum and the Dr Who bleeds through the output of the bass paralooper.

My question is this: could power filtering help reduce this noise? Is there a way of separating the grounds of the modules to reduce crosstalk?
Any help appreciated!

[Pushtone]

-a vanishing point type of 8 step sequencer (velleman led kit that does the same thing)

Sorry can't help you out but could you elaborate on how you used a flashing LED kit from Velleman to make a Vanishing point?
Is this a build shortcut?
Can you recomend doing it?
I see those LED kits all the time.

More on your topic...
I really like the way mikey did the power filtering in his awesome multi project with a little PCB. Nice work.
http://www.diystompboxes.com/smfforum/index.php?topic=46469.0

[j.frad]

That supply filtering could help, because actually everything bleed through! the ouptu of the modulator bleed to the filter, the 555 timer in the velleman sequencer ticks and the lfo bleeds white noise, I can plug my guitar into the ringer's input and get it back from the filter's output with no additionnal wires! I actually dont need any sound input to create noisy rythmic patterns, it's really cool! But it's not what I made it for, I was aiming at something similar to the seek wah at first, and I get way too much noise for that...

The velleman project is totally similar to the vanishing point but uses a different chip (cd4015). I haven't been able to put a switch to select 8/6/4 steps, because it needs additionnal parts (just an inverter), check this out:
http://www.geofex.com/Article_Folders/LFOs/psuedorandom.htm

It works exactly the same way, but the 555 timer does tick on my build (probably because of the commoon supply without filtering...), maybe using an lmc555 (is that the one that does less noise?) could help.

I chose that kit because I didn't want to bother etching a pcb and ordering parts as I had it in a local shop where I live...
I think the vanishing point project is more adequate for music use because the 4/6/8 steps selection is already included and it doesn't use a 555. It was very well though and if you have a chance, I would recommend taking advantage of the great work done by Tone God rather that buying the kit. That said, if you think a kit is easier, this one could be a good replacement...

[RaceDriver205]

It is unlikely supply filtering will help that much, as a 9V battery gives a flat DC output. Using shielded wires between effects will help (ground the sleeve).

[Paul Perry (Frostwave)]

The 'quiet' 555 is any CMOS based 555, like the 7555 or the LMC555.
But you might still want to isolate sections wiht 220 ohm resistors in the power rails & 100uF caps from them to ground.

[j.frad]

Thanks! That's the values I had no clue of.... As soon as it works better I'l post a build report.

It is unlikely supply filtering will help that much, as a 9V battery gives a flat DC output. Using shielded wires between effects will help (ground the sleeve).

yeah you're probably right, I'm still going to try it, the notes on the Thing modulator schematic sais that using 100k and 100uF filtering on the 567 helped reducing oscillator bleedthrough, I might also have to try to get a CMOS 567 too...

I'll see that in a while