An Analog Synthesizer for the 21st Century

flight · Joined: Sep 26, 2007 Posts: 2 Location: Seattle

(wow, I was expecting to get flamed for that post.)

The XR2206 is listed by Exar as NLIP; the ICL8038 - while still available through NTE- is discontinued or rather pricey for very low-budget people like myself; It does appear that I got the SSM2164 confused for a CEM chip... my bad. Isn't the LM13700 on the chopping block as well? I recall (hazily) something about the disappearance of the OTAs due to the old manufacturing process and some facilities being sold off...

Out of curiosity, by how much would the parts count increase if analog synth modules were designed using only discrete and common components? And is there any good literature on this? I know (from my EE professors) that engineers are "lazy", in the sense of "why reinvent the wheel" (which I totally understand from designing my own circuits, there is a substantial investment of time in designing from scratch), but is there a good place to look that explains the functioning of a synthesis system from the discrete level?

btw: Thanks for the welcome!

~flight

fluxmonkey · Joined: Jun 24, 2005 Posts: 708 Location: cleve

2206 is available from Jameco ($3.59), Futurlec ($4.95) or Electronic Surplus ($7.95)

13700 is available from Jameco ($1.20), Mouser ($.77) or Futurlec ($1.10)

3080 is available from futurlec ($1.90), Jameco ($3.54)

8038 is getting scarcer, but is available from Electronic surplus (now up to $6.95, after a recent run on them by SDIYers) or Futurlec ($15.95)

all those are one-off prices. that's what i found w/ just a couple minutes checking, i'm sure there are other sources for all. If you really get stuck, post to the "Wanted/For Sale - parts and components" electromusic subforum, someone here probably has an couple extra chips they'd sell you.

b

fonik · Posted: Thu Sep 27, 2007 7:23 am Post subject:

IMO your findings show that discontinuation of an IC does not necessary mean that it get's unavailable. new industrial/commercial solutions won't utilize obsolete ICs, i guess. so i bet there are zillions of leftovers of former common ICs like OTAs which will only be required by DIYers or repair services then. maybe i am wrong here, though.

Scott Stites · Posted: Thu Sep 27, 2007 8:23 am Post subject:

I got a flyer just the other day from BGMicro - 10% off the 8038 if you included a word in the order (and, no I can't remember the word! - Newsletter or something like that). Even without the discount, it's pretty decently priced at $3.95.

http://www.bgmicro.com/index.asp?PageAction=PRODSEARCH&txtSearch=8038&Page=1

I don't banana jack myself, but they do have some cool banana jack stuff there, too.

Cheers,
Scott

Scott Stites · Posted: Thu Sep 27, 2007 8:50 am Post subject:

slo · Posted: Thu Oct 18, 2007 7:26 am Post subject:

I'm trying to decide if I should put a level control at the output of the TH 21st Century ADSR, and if so what value pot. Looking at the patch over scheme the envelope has attenuation on the VCF input but not the VCA, in fact it goes into the Linear AM input on the VCA, which confuses me a bit. Should I build ADSR's with level amounts or just run it to a passive pot type module?

Tim Servo

loss1234 · Posted: Fri Nov 09, 2007 7:21 am Post subject: icl8038 versus xr8038??

can i use the xr8038 instead of the 8038? cant find the 8038 anywhere cheaper than 15!!!

etaoin · Joined: Jun 30, 2005 Posts: 761 Location: Utrecht, NL

I thought there only was one 8038 and that is the XR8038.

loss1234 · Posted: Fri Nov 09, 2007 8:30 am Post subject:

no there is the icl8038 from intersil

does th ask for the icl or the xr? i realized they have different pinouts. i dont know which one he asks for in his books but i dont want to buy the books till i KNOW i can get all the chips

thanks everyone

etaoin · Joined: Jun 30, 2005 Posts: 761 Location: Utrecht, NL

loss1234 · Posted: Fri Nov 09, 2007 8:41 am Post subject:

thats odd
my datasheet for the xr showed pins 8-16 being wrong.

let me find the sheet

i also had read a few other pages that said it wasnt a drop in replacement.

maybe i am totally wrong on this. i hope so because it would make it easier!!

thanks

loss1234 · Posted: Fri Nov 09, 2007 8:43 am Post subject:

im going to order some

thanks alot

philpeery · Joined: Nov 08, 2006 Posts: 137 Location: new jersey, usa

loss1234 · Posted: Fri Nov 09, 2007 9:56 am Post subject:

thanks
yes it does help
i must have read it wrong before i drank my coffee

thanks as usual

i posted in the wanted section so maybe someone on here can sell me a few chips

Wink

philpeery · Joined: Nov 08, 2006 Posts: 137 Location: new jersey, usa

How many do you need? I have a dozen, and could let a few go....

loss1234 · Posted: Fri Nov 09, 2007 10:20 am Post subject:

well i only need a few. but i was hoping to get a few of each of the three (2206, 566, 8038) so i wouldn't have to acquire massive shipping charges. but maybe if you only have the one type of chip, we could meet up sometime in the city.

just a thought.

why dont we PM and figure something out.

how close do you live to NYC? i have been dying to meet someone from the list in real life to discuss synth diy.

since i have started this stuff I have NEVER actually talked to anyone regarding this stuff (at least who cared Smile

my wife gets so sick of listening to my talk about my new circuits,etc)

anyway

23isgood · Posted: Fri Nov 09, 2007 1:56 pm Post subject:

According to Thomas, the XR version is slightly better than the ICL version. They are both the same chip and should work just fine. By the way these are getting scarcer every day. I bought four of the ICL version. I would like some of the XR's too. I have lots of 3080's if anyone wants to trade.

pete

JargMarbin · Joined: Oct 27, 2009 Posts: 2 Location: Austin

Has anyone built one of these and posted results on youtube.com or soundcloud.com so we can hear it? I'd love to know more about this.

Tim Servo · Posted: Thu Oct 29, 2009 12:25 pm Post subject: Re: can we hear one?

Tim Servo

By the way, if you live in northern California, make sure to attend the AH Nor Cal synth gathering on November 14th in Mountain View.

http://fdiskc.com/ahcali

I'll be there with modules based on all the Magic Smoke PCBs (including the 8038 based LFO and the XR VCO), and a couple of new goodies including a new prototype VCO with phase variable outputs and a new Thomas Henry DVD Smile

Tim (red carpet time) Servo

if837 · Joined: Apr 12, 2009 Posts: 56 Location: sweden

why can´t the just tell the visitors (lulu.com) what payment opions are available, without having to sign-up and go through an shoppingcart?
Do they accept paypal?

Tim Servo · Posted: Tue Dec 29, 2009 4:06 pm Post subject:

Hi If,

Yes, the navigation is a bit confusing at times. I've seen other sites like that where they keep most purchase-related info separate in the "shopping cart" area. There must be some reason for that, but I'm not a web / business guru so I don't really know why.

To answer your question - yes, they do accept PayPal. They also accept credit and debit cards, which is one more reason I like working with them. Smile

Tim (a bit confused at times) Servo