Posts Tagged ‘pt2399’

PT2399 build…

this is an older build now, but i wanted to post it while i’ve been on the subject to record the process. believe it or not, i still have some work to do on this one. i used a TL082 as a buffer for the mixing circuit. getting the gain set to my taste has been the toughest part. this one (unlike the last) is a bit low. it will all come in due time though. i’ve produced two solid builds this week (though really just debugging this one and one from scratch), and i’ll consider that a productive week.


the Stirgiform PT2399 delay…

two days worth of soldering and layout. it’s a combination of the Magnus Modulus and Rebote delay schematics. i couldn’t get the mixing circuit to really work from the Rebote schematic (an older version) without some serious distortion, so i just kind of reworked it on my own. here’s the schematic. i wouldn’t commit to it 100%, but it’s a start. tomorrow i’ll see if it level from bypass to effect works.

Arduino: second verse, same as first… sort of

well, not really. feeble attempt and making some sort of microprocessor controlled tempo clock, but a good exercise in the ATMEGA328s finicky behavior. don’t ask me what that squeal is. i think it comes from the way the input was wired up (mistaking the second sleeve as a synonym for ground) coupled with the PWM stream not having a negative offset, but who knows. eventually, i’ll move off the tone() crutch and start working with more interesting DSP. it’ll be nice to start using some of the memory on the chip.

i will also post the schematic for the delay pedal once i’ve got the values i want in it. i won’t have any time nor tools to tear into it until next week though.

Arduino: Analog Aerials

Essentially the oBITerator program with aerials instead of actual input signal. Of course, we’ve got to mix in the newly constructed PT2399 pedal. A little work needs to happen in the common-collector preamp which I’m mainly using to lower the input impedance into the delay chip. I’ll be recalculating those values soon as well as switching out a couple of the ceramic caps. They sounded good on the bread board initially, but I’d like to have a little less cutoff. Of course, no experiment would be complete without an LM386-based cigar box amplifier powering a Weber 12″ signature alnico.

PT2399 with BJT preamp



here’s a short clip of the delay circuit that i intend to convert to a stomp box. i’m still working out the kinks in the pre-amp stage to solidify the input signal from the guitar though. just a sample though to hear how it might sound with some guitar tones. more soon.

fuzzy PT2399 on baritone guitar…

Here’s a loose guide that I’m using to migrate the PT2399 into stomp box world. Here’s a dry run sample with a Gretsch Baritone guitar.

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Square-wave Oscillator Meets PT2399…

Square-wave Oscillator with PT2399… from abram on Vimeo.

Very short video of the waveform captured using Xoscpe of the PT2399 applied to the LM386 square-wave oscillator. Sorry for the bad focusing. I was in a rush. I just needed a visual capture for later analysis.

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…and here’s a clip of the aforementioned wave from from around the same time.

Bending notes with PT2399…

i’ve been experimenting with this PT2399 chip and using various schematics to create a digital delay circuit. the delay time seems to be directly attached to the sample rate since lengthening the delay time gives a nice decrease in pitch. i’m toying with the idea of dropping a time constant in around the controlling delay time circuit to see about achieving a “tape warble” sort of effect. we’ll see what works.

here’s the schematic i’ve been working with though the values i’m using are hardly similar.

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