Tube Delay Pedal?

While it's not exactly a tube delay, a friend once lent me a Fulltone tape delay which had a tube preamp. I am very much not a Fulltone fan, but I had to admit that this delay sounded pretty good. I would never use a tape deal because I'm perfectly happy with a digital delay, but man did the tube preamp sound good. I would love to trace just the preamp because cranked it sounded really good. It would be an excellent tube preamp project. Forget the delay!
 
While it's not exactly a tube delay, a friend once lent me a Fulltone tape delay which had a tube preamp. I am very much not a Fulltone fan, but I had to admit that this delay sounded pretty good. I would never use a tape deal because I'm perfectly happy with a digital delay, but man did the tube preamp sound good. I would love to trace just the preamp because cranked it sounded really good. It would be an excellent tube preamp project. Forget the delay!

Isnt the Fulltone a clone of the Echoplex EP2?
 
While it's not exactly a tube delay, a friend once lent me a Fulltone tape delay which had a tube preamp. I am very much not a Fulltone fan, but I had to admit that this delay sounded pretty good. I would never use a tape deal because I'm perfectly happy with a digital delay, but man did the tube preamp sound good. I would love to trace just the preamp because cranked it sounded really good. It would be an excellent tube preamp project. Forget the delay!
I like the sound of tape delay, I have a TRex Replicator Jr. as my main delay on my board. The only thing I'm not crazy about is the size, so if I like the way the tube delay works out I'll probably boot the Replicator to "studio only" duties.
 
I'm not sure how that works. 6111 heater takes 300mA, but the whole pedal only pulls 30mA?

SiB made "Echodrive", a 12AX7 driven delay using a PT2395, which seems to be an older version of PT2399 if I understand correctly. I haven't tried one in person, but I've been eying the used ones as I've heard good things and frankly adding tubes to things that don't really need tubes is kind of my thing.

EDIT: I did a little more digging and apparently the red version of the Echodrive uses PT2395, and the blue version uses MN3005. Pretty neat.

It seems that Deadend FX has a SiB Echodrive on the bench and might eventually sell a PCB ...
 
That would save me a lot of trouble:p

Right - ha-ha, but just in case you you get bored waiting for the schematic, check out this thread on the fuzzy side.

Apparently it's pretty simple :p
"The audio is first routed through one side of the 12AX7, then through the mix pot, followed by a JFET booster before hitting the front end of the delay IC. Delay time is variable via pot, or with expression pedal via a vactrol for isolation. Signal returns from the delay IC to the other half of the 12AX7, then back to the mix pot, and out."
 
My initial tube delay prototype got wired up over the weekend, and initial test sound pretty good. I used a PT2399, and it's basically a Mad Professor Deep Blue with the op-amp stages replaced with tube stages. I need to tweak the feedback values though, it self-oscillates with the control at 9 o'clock, I'd like to get a more useful sweep out of it.

At the request of a good friend I also threw together a PCB layout for a tube-driven FV-1 prototype, if that works well I'd love to try a tube FV-1 delay.

EDIT: I thought I had a picture of the board all put together, but all I could find was one of the assembled board from JLC. I'll get more pics tonight if I remember.

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A pseudo tape echo that I love is the old Ibanez EM5 that uses the M65831 chip.
I’ve been thinking about building one but with a PT2396 (that can replace the M65831, omitting a couple resistors, according to the datasheet) and a modulation section.

Im sure it’d be an excellent candidate for a tube preamp! The delay tone is outstanding, with a soft clipping/limiting section similar to the Ibanez DE7, and it’d be very easy to add a tone control to get slightly brighter or warmer repeats.
 
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I completely forgot to circle back to this thread when I wired up my prototype. So I mentioned the "PTube2399" which sounds pretty good, and I got some decent pictures of it last night. I was really happy with it, but I ended up feeling the same way I do about solid-state delays: PT2399 is a great delay solution... until you get into FV-1, and FV-1 blows PT2399 away. So this is as far as I'm going with the PTube2399 because the tube FV-1 pedal sounds amazing, and I have two on my board now :P

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You might want one of these then... although I'm not 100% sure about high voltage on a breadboard. :ROFLMAO:

(But @fig did it, so it has to be OK, right?)

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My entire body clenches up when I think about running any real voltage (or current) through these modern breadboards. I’ve had them come apart when trying to get the vinyl skin off the backing PSA, and while the construction is very clever, the conductors and the insulation clearances are both scary thin. Oh—with care, you can fit everything back in😉.
 
My entire body clenches up when I think about running any real voltage (or current) through these modern breadboards. I’ve had them come apart when trying to get the vinyl skin off the backing PSA, and while the construction is very clever, the conductors and the insulation clearances are both scary thin. Oh—with care, you can fit everything back in😉.
I don't breadboard much anymore, but I used to breadboard with 200V all the time. Never had any issues, but obviously don't touch anything when the circuit is powered up.
 
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