Tape Delay

[Aleph Null]

This is an original design that draw's a lot of inspiration from Jon Patton's Hamlet Delay. I've implemented a version of Jon's "Noise" control. I've also included DeadAstronaut's envelope modulation. I experimented with resistor and capacitor values in the modulation section and found I like the range I can get. It sounds pretty lush and is capable of pitch bending at higher "Warble" and "Delay" settings. It's not actually intended to sound like tape, but I couldn't resist the pun. Buffered bypass allows for tails.



I used a block of wood as a standoff for the circuit board. The block is hot glued to the enclosure and the board is glued to the other side. It's unconventional, but it's stable and effective. The 4.7k resistor in the feedback loop has been replaced in my build with a 25k trim pot. Most people would probably want a resistance of 10–22k there.



The schematic and layout for anyone that's interested. Where I to build this circuit again, I'd probably update the layout to include more power filtering for the 5V supply and also maybe add capacitors in the buffer feedback loops. As it is, it works well, but because the output of the PT2399 is always connected, it might be a good idea to test multiple chips. I had a noisy one that made motorboat noises when the "Delay" was above noon. A different chip fixed that. Additional filtering might help too.

[jimilee]

Very cool, no audio?


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[jessenator]

That's slick! tagboard buildign with clean wiring is a wonderful sight. And I do love the pun.
Is that a clear water slide print used for the graphics and labeling?

[jjjimi84]

This is so slick! I would love to hear it.

[Aleph Null]

Very cool, no audio?

I'll post audio if I can get it recorded. Not sure where I'd host it at this point.

That's slick! tagboard buildign with clean wiring is a wonderful sight. And I do love the pun.
Is that a clear water slide print used for the graphics and labeling?

Yep! Bought the enclosure powder coated, then used a water slide decal for the graphics. Three layers of acrylic clear coat on top of that.

[midwayfair]

spiffy

how's the warble control work?

[Aleph Null]

spiffy

how's the warble control work?

There's a voltage on the CCO pin that roughly corresponds with the input signal (I think the CCO pin is connected to OP1). Basically, the resistor and cap feed some of that signal to the VCO pin which changes the voltage at that pin, and thus the delay speed. At least that's my understanding. Smaller capacitors tended to increase the speed of the warble, producing ring modulation type sounds. Larger caps tended to slow the warble down and make it less sensitive to playing dynamics. 220nF–2uF worked best for me.

You can get it to do pitch bends (though not as extreme as something like the Clari(not)) at higher "warble" and "delay" settings, but most of the range is more chorus like. It sounds more natural to me than LFO based implementations because you can't make out a regular pulse. It's more like the subtle modulation you get with a good "hall" reverb versus putting a CE-2 in the feedback loop.

[midwayfair]

spiffy

how's the warble control work?

There's a voltage on the CCO pin that roughly corresponds with the input signal (I think the CCO pin is connected to OP1). Basically, the resistor and cap feed some of that signal to the VCO pin which changes the voltage at that pin, and thus the delay speed. At least that's my understanding. Smaller capacitors tended to increase the speed of the warble, producing ring modulation type sounds. Larger caps tended to slow the warble down and make it less sensitive to playing dynamics. 220nF–2uF worked best for me.

You can get it to do pitch bends (though not as extreme as something like the Clari(not)) at higher "warble" and "delay" settings, but most of the range is more chorus like. It sounds more natural to me than LFO based implementations because you can't make out a regular pulse. It's more like the subtle modulation you get with a good "hall" reverb versus putting a CE-2 in the feedback loop.

clever!

[gordo]

I have SO much respect for tagboard and perfboard projects.  WAY out of my league.  Superb build and the tip of the hat to JHS graphics looks so cool.  I'm really a fan of this style.  Class build all around.

[jimilee]

I have SO much respect for tagboard and perfboard projects.  WAY out of my league.  Superb build and the tip of the hat to JHS graphics looks so cool.  I'm really a fan of this style.  Class build all around.

Once you build some vero, you really appreciate a PCB. You should give it a try.


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[jessenator]

Once you build some vero, you really appreciate a PCB. You should give it a try.

*glares angrily at unfinished BeeBaa vero*
*builds another PCB project*

[jimilee]

Once you build some vero, you really appreciate a PCB. You should give it a try.

*glares angrily at unfinished BeeBaa vero*
*builds another PCB project*

Bwahahahaha


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[Aleph Null]

I have SO much respect for tagboard and perfboard projects.  WAY out of my league.  Superb build and the tip of the hat to JHS graphics looks so cool.  I'm really a fan of this style.  Class build all around.

Thanks, Gordo! I wasn't consciously channeling JHS, but it definitely is a similar vibe. I think it works because it reads well from a distance...like when it's on the floor.

Once you build some vero, you really appreciate a PCB. You should give it a try.

I've tried a few times to plan a PCB layout, but I always get intimidated and revert to vero. "The parts can go any which way! The traces could go anywhere!" With vero, it's always straight lines and vertical components. Then I go to box my vero creation and I think, "Maybe I should do a PCB next time." What software do you use to make your PCB layouts? Where do you get them fabricated, or do you etch them yourself?

[storyboardist]

Very cool project, man! Not seen that warble topology before. I was bored last night and whipped up a PCB in Eagle if you or anyone else wants it. I uploaded it to OshPark, but could do a run from Elecrow or JLC if there's interested to make it cheaper. Oh and I kept most of the components vertical for your vero instincts 

[Aleph Null]

Very cool project, man! Not seen that warble topology before. I was bored last night and whipped up a PCB in Eagle if you or anyone else wants it. I uploaded it to OshPark, but could do a run from Elecrow or JLC if there's interested to make it cheaper. Oh and I kept most of the components vertical for your vero instincts 

That's amazing! I see you even included the extra filtering I mentioned! Guess I'm going to build some more of these. 

I just noticed that my schematic shows C10 as 52nF, but my layout actually used 82nF. Anything between 47nF and 100nF will work. Also, R8 should be 22k. It might be worth noting in the build doc.

I can't tell you how tickled I am, David, I feel like I've won a major award.