IR3109 pcb avalaibility

Hi There,

I know it’s not listed in the shop but i was wondering if Olivier (or anyone for that matter) had a IR3109 filter pcb for sale. As I know a guy who has a IR3109 chip to swap, that would have been just great if i could buy one and get a “rolandified” shruti-1.


I’ll receive a prototype board in 10 days. Once I have built it and confirm it works, I’ll do a (very) small run, which may take another 15 days before being available on the shop.

Many thanks for the quick reply Olivier. Looking forward the boards being available in the shop.

okay, even when you only do a limited run, i’d like to get one IR3109 board.

I have one of these chips…put me down for a board too!

Put me down for a board as well!

Note: from the photo of the chip, this looks like a fake. I bought some IR3109 from 2 sources and received similar looking chips, which were not only fakes, but fakes of the dangerous kind (they short GND and the power rails).

All the “good” IR3109 I have seen are in this funky, rounded package:

see, id love to grab a 3109 but really worried about getting ripped off. Wouldnt even know how to test it.


Some bastards out there…

My advice is simple: don’t build this board unless you have the chip from a trusted source (broken Roland synth, NOS from repair shop…). The ratio of genuine / crap is low, and it is already a hard time for people looking replacements for their Roland synths that I don’t want to aggravate the situation. I’ll be doing a run just because I want one for myself and I need to amortize a bit the setup fee for the board, but this will be a small run and there won’t be more.

And don’t fantasize on this ; I’m pretty sure that I can revise the SMR-4 board to make it sound similar.

The eBay pic shows clearly a Laser engraved Chip, at the time these chips were produced there were no Laser Engravers available… anyone in need of a CEM 3399 ??? Or maybe some other rare vintage Laserengraved Chips? SSMs?

The engraving is quite easy to recognize - at an angle, the marking on the ship looks dull, brown, and shallow

So it’s pretty much a “tell us the number, date-code price and quantity ; and if it’s worth it, we’ll laser-engrave a few 74hcxxx for you” business

Did you get your money back on the fakes out of interest?

I am intrigued. The AMS filter clone using this chip sounds awesome.

But sadly too much of a noob to trust myself to not get skanked.

Cheers for the info tho!


I got the money back from utsource, yes.

I wrote this to (the guy from the eBay auction of the IR3109):

Hi! How could I know that this IR3109 is fully working? And, how is possible that is new?

And that’s what he told me:

Thank you very your for your message.
These parts came from an US supplier that tested all of them before shipping.
I ordered a few parts to repair two ROLAND vintage syths, 100% OK.
Once they have a minimum order required I bought more than I really need.
So, I’m selling the exceeded stock, 3 buyers had received the parts in perfect working order and left positive feedback, please check.
If not happy, you have 30 days from the purchase date to return the parts. No questions, no fees! Sounds good?
Any questions, please feel free to ask.

If someone is willing to buy a chip there and send it to me for verification… But given the high price I certainly wouldn’t take the risk.

Apparently… Boss PH2 phaser pedals use 2 of these, and can be found cheap…
If only my desoldering skills were rather better!

lots of PH2s on ebay - lots around £60 Buy it now…


\\my desoldering skills are likely to be signicantly worse than yours Paul… :)~

I might buy a Mutable IR3109 board and sit on it until a chip becomes available. Although my pile of unfinished projects gets larger …

So any updates on the prototype?

Board assembled, working, unit sold, 25 boards reordered, delivered in 12 days.

excellent! Wheres the list :slight_smile: