Deep Blue Delay with modulated trails

[Geiri]

Hey there guys! I wanted to post this layout of the Mad Professor Deep Blue Delay with modulated trails. I will post the modulation circuit separately as well if you've got any other PT2399 circuit to try it on.

DBD Layout is copied from Mark, so credit goes to him. I don't like the voume control so this layout is the 3-knob version (like the original). There are two 9V and Ground places. I just use a wire from the top connection to the bottom one. You can use whichever method suits your building style. Just make sure to connect BOTH 9V and Ground strips.

I've built this myself and it works. It sounds great as well! I recommend using a 1K pot for the depth but if you want insane pitch shifting on the trails, use a higher value pot. I think 2K will still work fine. Max depth should be very very audible. 1K does the trick for me.

Here's the layout:


Feel free to ask questions if there are any!

[Milkit]

Top man Geiri.  Do you have a demo please bud, I'd love to hear it.  

Boss lad!

[alltrax74]

Yes i'd like a demo too as i have no idea what modulation trails mean :-)

[Geiri]

Sure guys! It basically shifts the pitch of the delay trails up and down (depending on the depth pot you're using. Going above 2K will cause some intense shifting when you turn it up.) When the trails shift up and down, it sounds a bit like a chorus.

This video has way too large value pot for the depth and you can hear it:
YouTube link

Here's another one with a 1K pot for depth:
YouTube link

[alltrax74]

Nice !
Thanks man

[Milkit]

Smashing, thanks dude!

[IvIark]

Nice one matey

[Milkit]

Hi Geiri,

The trace cut on the 2nd or lower 9v rail, does that need to be there?  Nothing seems to terminate after the cut, unless something should be there?

Thanks,

Matt

[Geiri]

Oh yeah you're right. I have no idea why that cut is there. Nothing connects there so just forget about it. I'll update the layout as soon as I can!

Cheers!

[Milkit]

Cools, no worries dude.  Thanks for clearing it up for me bud.

[Geiri]

No problem!

[Kinski]

This is awesome!

[Milkit]

Hi Geiri,

I built this tonight.  It sounded cool, but the repeats sounded like they weren't there.  Cross examining your layout with Mark's confirms that there are two caps, a 22n & a 47n missing from the repeats section on your layout dude.  I added these caps to my board & it worked bob on!

So you can consider the layout otherwise verified, just needing to add the aforementioned caps.

Great work Geiri, thank you so much man.

Matt  

[Geiri]

I have no idea how I managed to do that. Thanks for letting me know! I'll update the layout and post it here.

Cheers!

[Milkit]

No worries mate.  Just one other thing though if I may, my speed pot seems to have no effect on the signal, do you have any clue as to why that may be, Geiri?  I've made two of these & both have the same issue, just wondering if there could possibly be something missing from it perhaps?  The LED for the ldr doesn't "pulse" (I assume it should do?) it's constantly on.  Could I have duff TL072's?

[Milkit]

Think I may have cracked it.  The + of the 10uf Elec cap needs to connect one row down to the Speed 1 termination.  Then the LEDs pulse & speed alters with the pot rotation.

[Kinski]

Hey, which color should D1 and D2 be? RED?
Also, D2 and LDR should be facing each other, right?

[Milkit]

I used red LED's & I have the LED & LDR facing each other, coupled together with heatshrink tubing.

[Kinski]

Thanks!

[Kinski]

Built this. Sounds great. However, the repeats dont get anywhere near endless. I just get about 4 or 5 repeats when all the way up.

Any ideas? I used a 50k pot as the layout says.