First of all, I have an Effectron II ADM 1024 and it sounds Amazing, particularly the way it clips. I am on the hunt to figure out, if possible, how to retrofit these to slave to an external MIDI clock, or otherwise sync to a DAW.
I’m posting this because this has been quite a research project and if you’re trying to do the same thing, maybe you’ll have an easier time.
I got mine completely dead for ten bucks from a friend, popped the top off and got it to power up (I think it was a fuse… I’ll confirm that and update this)
Mine had dirty pots which I WD-40’ed and now sound pretty much perfect. I think my input gain still crackles from time to time but I don’t ever need to adjust that after getting the primary level. I also had to replace one Potentiometer since the knob shaft was broken off. I was able to do that easily.
Some stuff I learned:
- The only place to get a schematic for the ADM 1024, unless DeltaLab writes me back with a copy, is HERE. For the sake of attribution, I’m going to leave this as an external link, but I have the files from that site saved and if that site ever goes down, I’ll upload them to my own site. The schematics are pretty hard to read and I think there are some holes in the scans. Better than nothing.
- As far as I can tell, it’s totally possible and relatively easy to increase the maximum sample/delay length in these things just by adding a resistor or two and some inexpensive ram chips. See HERE. On that page the author increases an ADM 1020’s max memory from around one second to around two seconds by adding three additional chips. What I’m not sure of is if you can up it to four seconds by adding nine. The RAM, I’m pretty sure, is MK4564-20. There are some on eBay right now for about two dollars each. Found an Allegedly identical part for around eleven dollars each, so maybe they no longer get made.
[quote from same site:] DeltaLab used a special type of Adaptive Delta Modulation (ADM), which they continuously improoved over the years. You might take a look at US-Patents #31720, #4190801, 4254502, #4305050, #4313204 and #4462106. This is much more sophisticated than the cheap ADM projects that were published in various magazines as musical diy projects. (Elrad Delta-Delay, and others) The great thing is that the patent text even has component values shown !
- I’m currently in discussion with someone over at Molten Voltage about whether or not one of their PedalSync products can be used to make my ADM 1024 slave to MIDI Clock from my computer. Probably their MV-64. I will update this if I get anywhere.
- I’m also currently talking to some nice stranger via the diystompboxes.com forums about the same thing.
[On that forum “q_u_e_s_t said:]…the clock comes out on pin6 of IC38 (4528B) [see above schematic link]. it is a 0 to 12v digital signal varying from 250kHz to 1MHz. it has a fixed pulse width of 0.5?s for the high period, and the low period varies in length to make up the remaining time… [and]…the way this delay pedal works is very similar to BBD. basically, BBD is a long line of buckets that hold an analog voltage level. but, in this device, its a long line of buckets that hold a digital voltage level. as a result, it needs to be clocked faster, as 1 bit of data (1 logic level) doesnt carry as much information as 1 analog bucket. so you need a bunch of digital buckets to get read in the same amount of time. so, what this means for their kit, is wether or not it can clock fast enough. ask them what the highest clock rate on the kit is. it needs to go to 1MHz…