Curtis 3340 Has been remanufactured

johnny83 · Post by **johnny83** » Fri Jun 03, 2016 4:43 am

Dear all, I've been speaking with onchip for the last 3 months and they have already produced a new batch of CEM 3340. They are available for $15 each! We have tested them and they are revision G and pass our tests on the original Curtis test boards and also various synths we tried them in.

The person to contact is susanonchip@covad.net, she has been remarkably helpful and can process your order. Please be aware that revision G has meant the following:

"After reviewing the prior specifications I did decide to change the minimum VCC spec. The old VCC min. was +10V and the new VCC min. is +11V. This is based on my own bench experience with several versions of the device. Many devices will work with a VCC of +10V and others won’t. Devices that won’t work at +10V should easily work at +11V or higher. This is the only specification that we’ve changed" John Borg (Onchip Engineer)

Additionally they have no plans to release the 3310, 3320 and 3360 yet but I think if they see the success of the 3340 it may be apparent the market needs them. I am in communication with them and will continue to push for the other chips to be brought back but to be honest the release of the 3340 is great news as that was the most common curtis chip used.

Here are the price breaks for anyone wanting to get more than a handful:
1 - 499 = $ 15.00
500 - 999 = 12.82
1000 - 4999 = 9.64
5000+ = 7.46

Postage is in addition to this.

I hope you enjoy and spread the word!!

sneak-thief · Post by **sneak-thief** » Fri Jun 03, 2016 4:49 am

Unbelievably great! I've previously had to pay handsome sums for these when repairing synths.

johnny83 · Post by **johnny83** » Fri Jun 03, 2016 5:01 am

To remanufacture the other chips would be $75k per model and I'm not sure if that includes a batch run as well. I'll keep digging and see what's happening but this could change the world of modern synths and modular synths with new found availability of the CEM chips!

aladan · Post by **aladan** » Fri Jun 03, 2016 6:55 am

I'll ask the obvious question here: who's organising the group buy?

Altitude909 · Post by **Altitude909** » Fri Jun 03, 2016 7:11 am

good news indeed. 101/202 clone anyone?

moylando · Post by **moylando** » Fri Jun 03, 2016 7:22 am

didn't see this coming. this is the golden age.

johnny83 · Post by **johnny83** » Fri Jun 03, 2016 7:32 am

to be honest a group buy per region makes sense however you would still have to pay distribution for each person and given the import duty on high volumes it might be better to order low volumes individually and ask them to ship directly. Alternatively you could always see if they will let you buy in bulk say 100+ and you have 5 or 10 people they need shipping too that may be a better option

ratsnake · Post by **ratsnake** » Fri Jun 03, 2016 9:22 am

some stupid questions -

what is a typical batch size for on-chip?
is there demand for this chip apart from synths in 2016?
are we doing a batch order and then selling them for 80 bucks a pop?

dogfaceaudio · Post by **dogfaceaudio** » Fri Jun 03, 2016 9:58 am

I'd be interested in working with other wigglers to develop an open source VCO based on the CEM3340.

Altitude909 · Post by **Altitude909** » Fri Jun 03, 2016 9:59 am

seeing that you can just buy one for $15, I dont see a markup market for these.

I ordered 6 a month or two back when I first heard about this and onchip was happy to sell them in those quantities

elmegil · Post by **elmegil** » Fri Jun 03, 2016 10:06 am

dogfaceaudio wrote:I'd be interested in working with other wigglers to develop an open source VCO based on the CEM3340.

First place to start is the schematic in the datasheet.

You mainly have to determine options like range, sync and wave shaping.

Note that Paul Schreiber has stated on Facebook that the tempco on this chip is less than great because the original design was intended to be auto-tuned every 5 minutes in the P5 anyway. Craig Lee has responded that he has a couple DIY VCOs based on this without any major drift problems. So any open source design needs to thoroughly test the temperature stability and if necessary find a way to compensate (or else give a big disclaimer about the conditions where drift might be a problem).

emdot_ambient · Post by **emdot_ambient** » Fri Jun 03, 2016 10:26 am

elmegil wrote:
dogfaceaudio wrote:I'd be interested in working with other wigglers to develop an open source VCO based on the CEM3340.
First place to start is the schematic in the datasheet.

You mainly have to determine options like range, sync and wave shaping.

Note that Paul Schreiber has stated on Facebook that the tempco on this chip is less than great because the original design was intended to be auto-tuned every 5 minutes in the P5 anyway. Craig Lee has responded that he has a couple DIY VCOs based on this without any major drift problems. So any open source design needs to thoroughly test the temperature stability and if necessary find a way to compensate (or else give a big disclaimer about the conditions where drift might be a problem).

Note that Digisound 80's design for a 3340 oscillator has been around for decades and is a great place to look. It implements most (all?) of the features on the chip itself, along with adding some nice to haves (like an octave switch, sine waveshaper, bipolar -5V - +5V sine and triangle waves available separate from the four 0V -10V waves, soft sync and both positive going and negative going hard sync). But it also has a few potential flaws (not all outputs from the chip are buffered).

There are other posts here on MW about that oscillator, as well as plenty of info on it online.

elmegil · Post by **elmegil** » Fri Jun 03, 2016 10:28 am

seancostello · Post by **seancostello** » Fri Jun 03, 2016 10:41 am

Are these chips all DIP, or are there SMD versions available?

elmegil · Post by **elmegil** » Fri Jun 03, 2016 10:59 am

My understanding is DIP only.

clusterchord · Post by **clusterchord** » Fri Jun 03, 2016 11:05 am

these are fantastic news. i kept postponing buying a batch of originals to stock-up, while the price was going up and up, and at least this once - waiting has payed off weeeee haaaaaaaaaaaa

Altitude909 wrote:seeing that you can just buy one for $15, I dont see a markup market for these.

I ordered 6 a month or two back when I first heard about this and onchip was happy to sell them in those quantities

have you done some A/B in them machines btwn the old and new CEMs ?

thanks

Altitude909 · Post by **Altitude909** » Fri Jun 03, 2016 11:16 am

^
Dont have old CEMs

gbiz · Post by **gbiz** » Fri Jun 03, 2016 12:18 pm

Fantastic news.
fingers crossed for the 3360 next

Robscorch · Post by **Robscorch** » Fri Jun 03, 2016 12:23 pm

clusterchord wrote:
have you done some A/B in them machines btwn the old and new CEMs ?

thanks

Man jumping the gun a bit wait till they get in some hands first this is still kinda that new. Also will be identical aside from the VCC being 11 not 10V should make no changes whatsoever to the sound. That's unless the chips just suck, but I highly doubt it. Wouldn't be in the manufactures interest specially considering the up front cost of setting up this DIP.

phutureboy · Post by **phutureboy** » Fri Jun 03, 2016 4:23 pm

gbiz wrote:fingers crossed for the 3360 next

+1
& 3350 too...

analoglsd · Post by **analoglsd** » Fri Jun 03, 2016 4:27 pm

dubnspace · Post by **dubnspace** » Fri Jun 03, 2016 5:05 pm

looks like they filed trademarks on the 3350 VCF and 3374 VCO on the same day as well:
https://trademarks.justia.com/867/47/cem-86747547.html
https://trademarks.justia.com/867/47/cem-86747549.html

graphixsounds · Post by **graphixsounds** » Fri Jun 03, 2016 5:49 pm

dubnspace wrote:looks like they filed trademarks on the 3350 VCF and 3374 VCO on the same day as well:
https://trademarks.justia.com/867/47/cem-86747547.html
https://trademarks.justia.com/867/47/cem-86747549.html

cool so what does this all mean besides making repairs for vintage cem synths easier? is a manufacturer going to pick up the ball and make some new synths with this?

Robscorch · Post by **Robscorch** » Fri Jun 03, 2016 6:14 pm

graphixsounds wrote:
cool so what does this all mean besides making repairs for vintage cem synths easier? is a manufacturer going to pick up the ball and make some new synths with this?

Oh we are going to have a field day in the DIY now and we can resurrect a few PCBs out there that require these chips. The unobtainium kills dreams. Yes manufactures will be hip to it and I imagine we will see a new Prophet of some sort at least in Euro form.

oldcrow · Post by **oldcrow** » Fri Jun 03, 2016 6:47 pm

Are these from old wafer stock or a fresh wafer process?

MOD WIGGLER

MOD WIGGLER

Curtis 3340 Has been remanufactured

Curtis 3340 Has been remanufactured

CEM3340 rev G re-issue group buy