HEY PEAKE... the 258

Peake · Posted: Wed Aug 06, 2008 12:27 pm Post subject:

Oh no, thread tangent/hijack. Looks like I'll have to start a new one (and a new one, and a new one..)

Peake · Posted: Wed Aug 06, 2008 1:06 pm Post subject:

And what a surprise it would be if anyone actually produced vintage power supplies- HA! Laughing

What does the Buchla 258 sound like, for those who have never used one, or can't, a rough mix teaser, all Buchla 200, but be careful: VINTAGE POWER SUPPLIES CAUSING PITCH MOVEMENT!!!:

BuchlaETeaser.mp3

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BuchlaETeaser.mp3

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numbernone · Joined: Aug 16, 2006 Posts: 477 Location: new york city

Oh you are such a LIAR!!!

That was like MUSIC music, and EVERYONE knows Buchla are only good for BUG MUSIC.

WHATEVER it was, it sounded good

verbos · Joined: May 09, 2007 Posts: 15 Location: new york

paults · Joined: May 08, 2006 Posts: 21 Location: Fort Worth, TX

Mike:

A informative thing to post (although a bit of work on your end) would be 2 short pieces (say 30sec each), with the only thing different are the power supplies. That way, we could all listen to the differences to understand better how the Buchla modules interact with the supply.

Peake · Posted: Wed Aug 06, 2008 11:43 pm Post subject:

verbos · Joined: May 09, 2007 Posts: 15 Location: new york

Peake · Posted: Thu Aug 07, 2008 12:50 am Post subject:

My second guess was Vlad, no joke...

I'll put the Buchla PS on the VOM someday and see what it says.

norman phay · Posted: Thu Aug 07, 2008 3:47 am Post subject:

What actually would be interesting would be to close tune one of your 258s to a digital oscillator to hear how it beats, in its sinuous fashion (I imagine) against a rock-solid tuned raw wave source. Could actually be interesting/curious (if a little obsessive, heh) to do this for a bunch of diff't VCOs. I'd be up for doing that with the VCOs I have.

I digress, anyway, just wanted to say a/as always, you under value your musical ablilties, that's a nice little clip, and I wanted it to go on longer. and b/I'm interested in seeing what you come up with. I don't have any ua726s, but dating back to when I made an abortive attempt at building up an elektor/formant setup (the oscs of which use 726's), I've got a couple of little boards that this guy made up years ago, that supposedly are a drop in for the 726, when they're made up.. I've had the things in the box for nearly 20 years! Pretty scary, eh, how quickly it passes. I have a couple of 258-inspired VCOs which I'm likely going to flog in the next month or so, so if you do a DIY version either as a layout or as a PCB, I'd be up for a few for sure.

As an aside, the only 726 VCO I have is the one in my SH09, a nice chunky-soundling little instrument. I don't know how much a contribution to the instrument's tone and feel the 726 makes though, overall.

numbernone · Joined: Aug 16, 2006 Posts: 477 Location: new york city

verbos · Joined: May 09, 2007 Posts: 15 Location: new york

Funky40 · Posted: Thu Aug 07, 2008 11:16 am Post subject:

fonik · Posted: Thu Aug 07, 2008 2:11 pm Post subject:

Peake · Posted: Thu Aug 07, 2008 6:19 pm Post subject:

"back to vintage PSUs..."

Obviously I'll start a new thread in which to post the artwork (and THEN people can again go for whatever tangent amuses them).

"I for one do not think the uA726 has anything to do with the sound. I bet Mike's on to something with the power supply. The big system I work on all the time has HUGE and new power ones and the tuning on the oscillators, both 258 and 259, is very stable."

I don't know. It sounds like each oscillator is moving a particular amount, independently (not holding their own pitch well enough to maintain a solid pitch relationship to each other, with the PS moving all around equally).

mono-poly · Posted: Fri Aug 08, 2008 2:34 am Post subject:

verbos · Joined: May 09, 2007 Posts: 15 Location: new york

Peake · Posted: Fri Aug 08, 2008 2:29 pm Post subject:

Later today I'll edit this post and attach a soundbite of just the bassline. We can listen and decide for ourselves.

BTW, how drifty are your "C" clones on simple-answer using the SSM? I know that there is much more involved in drift than just the expo converter plus tempco...

verbos · Joined: May 09, 2007 Posts: 15 Location: new york

Peake · Posted: Sat Aug 09, 2008 5:07 pm Post subject:

Hmm, there is the chance that the first soundbite is at 48KHz. This one is correct. Just a sketch of the intended ending. Note that the oscillators in the bass are indeed not too badly beating -randomly-, but are definitely gaining beef from mistracking.

http://share.ovi.com/media/Peake.public/Peake.10006

norman phay · Posted: Mon Aug 11, 2008 7:02 am Post subject:

Nice, as before. Timbrally, I liked the 1/4 note echoed "doinks" at the beginning with the little high resonance that changes slightly from note to note best.

Luka · Joined: Jun 29, 2007 Posts: 1003 Location: Melb.

i was just doing some searching around the the ua726. seems as tho HKSS is the one and only ebay option at the moment. i found some SDIY comments that confirmed that the HKSS ua726 chips were in good working order and then i found this damning page

http://home.freeuk.net/bandpass/hkss.htm

extreme bad rep points for HKSS :S

the next best option was 5 chips for US$150 from some random seller on a website when i googled ua726 NOS.

i think ill avoid designs using this part now, too much hassle, unless someone can point me in a cheaper more trustworthy direction

Peake · Posted: Sat Aug 16, 2008 9:41 pm Post subject:

I've sourced all of the rare parts for my 258bs, excepting the 726, and found great prices at none of the usual sources, far better than anything on ebay. I still hear of great deals on ebay, but the Buchla parts don't seem to be among them. Check the prices I've listed in the other thread, original post, for reference.

Modding this artwork for the SSM2210 etc. should be easy. I'm sure that any of us could do it. Remember, a clone of the "c" is also apparently on the way, and IIRC it will not use the 726, if you wish to go that route.

Luka · Joined: Jun 29, 2007 Posts: 1003 Location: Melb.

thanks peake

i really look forward to this

Peake · Posted: Sat Aug 16, 2008 10:20 pm Post subject:

I've updated the original post in the 258 clone project thread to offer options to the uA726, recommending the THAT 300 quad NPN IC ($4.60 each, available singly; one of them completes the expo converters for -both- oscillators, versus needing two SSM or LM at more than $5 each.).

I don't know where to put a tempco in the original design, however, so I'll leave that, as well as the possibility of 1V/Octave response, to other people to post, or not...if you use a polycarbonate/polystyrene timing capacitor as in the original, it's not a very unstable design like the Moog 901b, even less so if you use a modern power supply. I'd be interested in hearing people's thoughts on that subject later on...