"Noise Ensemble" - simple PT2399 abuse!

[frequencycentral]

I've spotted a small problem with the pcb layout. C5 is shown connected to pin 15 of the PT2399. It should go to pin 14. Everything else seems okay.

Rick

Ooops! Thanks! Fixed and re-uploaded!

[anchovie]

Too bad solder suckers are usually plastic, or you could DIY a metal detector to help you find it.   

Panic over! Discovered this morning that she'd shoved it in a kitchen drawer, next to the freezer bags.

[DougH]

Recorded in a snatched moment (I was using one eye to make sure that a little girl didn't harass a guinea pig!):

http://www.youtube.com/watch?v=6tAS8-J2SX4

Minor "Shambles", leading into major.

Now that's pretty cool...

Wild stuff, mon... Really wild...

[wavley]

I think this is next on my build list after I finish my Phase 45 as a project for school, I was working up what I needed to order so now I need to add some PT2399 to my list.

[p_wats]

Excellent. I just received a crapload of PT2399s from Tayda for experimenting and this will go straight to the top of the list! Thanks.

[culturejam]

Awesome. 

[Skruffyhound]

LOL - when she walks past with the solder pump! Those things are just children magnets.
Nice design. I want to see where this goes, so I'll write this comment and wait for updates

[p_wats]

I breadboarded this last night. Lots of dirty, dirty fun!

Messing with the values of the 47K resistor and "shambles" pot can yield interesting results (leaving the  47K out completely "cleans up" the repeats--as much as possible in this circuit--and could be fun to have on a toggle).

I added an LDR in series with the shambles pot for extra nonsensical fun. Not sure if I'll actually box one of these up, as my Clari(not) build fits a similar need, but this is definitely a fun circtuit with very low parts count! Excellent job.

[Earthscum]

So, I finally had my board cleared of all circuits and tried this out tonight... it's awesome, except for the massive squealing and basically just nasty feedback I'm getting... anyone else? I love the sounds I can get when I play, but I don't like the sounds I get when I don't.

[anchovie]

I've had no squealing problems with it, in fact I've found that the comparator input stage gates quite heavily when the signal level is low enough. Make sure you've definitely got the demod cap on pin 7 and not pin 8 - pin 8 with this circuit introduces a lot of noise, likewise there should be no filter cap between 9 and 10. You could maybe try increasing the 10nF cap to take more of the digital hash off.

[metallo]

Very nice circuit, thanks for sharing!

[Earthscum]

Ok... so, noise was apparently caused by the 47k. I yanked it, circuit works beautifully... well, in a manner of speaking   

I tried a 10k, and it didn't have any effect different than the 47k. Guess I know what one to leave out! Anyways, I ran this into a Jfet buffer with some top-end rolloff, and it smoothed out the 'staticy' portion of the initial signal to something more along the lines of a CMOS distortion. Only other thing I may do is up one of the 10k's to decrease the tails just a hair, or a simple pot to adjust the decay of the tails.

I'm really digging on the sound! This one may get added to my noise box project... yeah, it will. I haven't heard anything quite like this... even the Clari doesn't get this far into the "nasty" territory! This thing is so deep in, I'm actually surprised I can still make out notes and chords, but that's the beauty of it. It's usable noise, lol!

[anchovie]

leaving the  47K out completely "cleans up" the repeats--as much as possible in this circuit--and could be fun to have on a toggle

Ok... so, noise was apparently caused by the 47k. I yanked it, circuit works beautifully... well, in a manner of speaking   

Interesting...I used the 47k after originally connecting the comparator output directly to the delay pin - that gave me a choppy tremolo rather than an echo which is why I added the resistor to limit the level of the modulation signal.

I guess the chip was never designed for a circuit like this, so if there's a variance with this particular (dis)function then at least it's something people are now aware of when building.

[p_wats]

Last night I replaced the 10K resistor between pins 11 and 12 with a 50k pot and it is very useful for dialing in just the right level of repeats. At 0k it's almost a "wet only" boosted signal and at 50K the repeats are just a ghostly whisper.

I used something like an 82K resistor in place of the 47K and it seems to put it into nice crazy territory, so I'll likely add a toggle to disconnect it completely depending on what sound I want ("clean" or crazy).

Add an LDR or two for wacky fun and I might just have to box this up after all!

[p_wats]

Alright, so I've officially got this to a point that I think it's most versatile and usable in many settings. There are now 5 knobs instead of two though(!): volume, delay time (shambles), dry level, wet level, modulation(repeat craziness).

One of the 10k resistors seems to affect level of repeats and another effects level of dry signal. With pots replacing those (in series with resistors to attain optimum sweep) you can now have a huge variety of wet/dry combinations.

Also, I my experience with the 47k resistor is as follows:

- with it in place the repeats are zany
- without it in place the repeats are "clean"-ish (no jumper, just breaking the connection)

That means that a 47k resistor in series with a large value pot (1M in my case) can allow you to control how zany the repeats are (with 1M being enough resistance to simulate a broken connection between the pins). This becomes the "modulation" pot.

I played with the cap values too, but didn't really find anything too exciting, so left them alone.

Thanks for the fun circuit--this is the perfect sort of thing for a breadboard noob like myself to cut my teeth on!

[John Lyons]

Paul
Can you draw up a schematic of what you have please?
I'm curious to see what you did.

John

[glops]

Paul
Can you draw up a schematic of what you have please?
I'm curious to see what you did.

John

+1   I would like to see your additions, as well.  This is a GREAT circuit! I'm gonna call mine, the Shambler.

[p_wats]

Blech...schematics are not my friend. I started drawing one but it was an unreadable schematic/layout hybrid.

I'll perf mine up then make sense of what I did on the breadboard and try to come up with pics/drawings.

Suffice to say that, when looking at the vero layout, I did the following:

- added a 1M pot from R3 to pin 10

- replaced R5 with a 1k resistor in series with a 50K pot to pin 14

- replaced R4 with a 250k pot

- replaced R1 with a 5.6K resistor and P1 with a 50K pot

I'll probably also ditch the volume pot (or replace it with a trimpot).

Anway, that's it for now, I'm off to try to perf this thing so I can post a layout!

[anchovie]

Great stuff Paul! Glad you've enjoyed playing around with this - I knew when I posted the circuit that it could be expanded upon and I'm pleased to see that it's been experimented with.

[e45tg4t3]

Hi there,
Paul based upon your last posts i drew a schematic, but i don´t know if they are like you had them in mind... So would you please be so kind an look over it?

ftp://epa-art.dyndns.org/Stuff/NE%20Schem.png

Ben