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magman
Joined: Feb 04, 2009 Posts: 363 Location: Liverpool, UK
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Posted: Wed Feb 11, 2009 11:57 am Post subject:
Magazine based Synths - Wireless World Synth Subject description: 1st Project is a biggy, starting from scratch on a new synth. |
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It was a synthesizer article in a magazine that got me interested in electronics anyway, (PE Sound Synthesizer from 1974) so its about time I started building one.
I've got a very extensive collection of magazines which have loads of synth related articles, so I thought I'd start off chronologically with the first one I've found - the Wireless World Synthesizer, designed by Tim Orr.
The link on CAG for this synth doesn't work at present, but I have managed to find it here:
http://www.timewind.se/schema/Wwess/
My first shout out is to see if anyone has used any of these circuits yet and try and pick their brains to see if there are any pitfalls I need to avoid.
Next, I'm not planning to build this synth in isolation. There are a number of area's for this project that I'm sure this community will be of great help with.
I'm planning to build the synth in a modular way, that way any PCB's I design can be adapted for other uses. I'm not planning to build it into a common rack format though, as I'm leaning towards building it into a case a la EMS Synthi A.
There is a long way to go in the design though (including re-learning how to use PCB design software, as the last time I tried this was under DOS 5.0). Any PCB's I get working, I'm planning to make available on the forums. I'm also thinking of adopting some standards from other modules - for example picking a common power supply connection method (suggestions gratefully received).
I've already started collecting parts, including the critical SG1495 chips (I picked up some MC1495's from eBay which should hopefully work) and a shed load of 741's and BC182's. The 1495's were key to if I even started on this build. I'm also going to stick as close as I can to the original design, once its built and working, then I can start playing (in an elctronic sense) with it.
Breadboarding is likely to start this weekend.
Welcome to the start of my long journey to building a new old synth.
Magman |
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v-un-v
Janitor
Joined: May 16, 2005 Posts: 8933 Location: Birmingham, England, UK
Audio files: 11
G2 patch files: 1
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Posted: Wed Feb 11, 2009 1:57 pm Post subject:
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Hey cheers for sharing this! |
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forbin
Joined: Jan 29, 2009 Posts: 120 Location: Fremantle, Australia
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Posted: Wed Feb 11, 2009 4:20 pm Post subject:
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Funny I was reading my faded photocopy of that article just recently. I don't intend to build it all but I have just purchased the 1489 as I plan to build the VCF. I have done a fair bit of the modeling of the design for it using SPICE and it should all work. The Log converter is a bit strange in being a piecewise approximation but it will probably be fine for a Filter. I just need some time to finish off the PCB now!
I have been on a bit of a Filter splurge recently and have made a few oldies including the ETI 4600 VCF. It is all a bit of a work in progress at the moment... |
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magman
Joined: Feb 04, 2009 Posts: 363 Location: Liverpool, UK
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Posted: Wed Feb 11, 2009 4:39 pm Post subject:
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forbin,
I will definitely be interested in how your work progresses with the VCF (why re-invent the wheel).
I'm going to concentrate on VCO3 first, as this looks something like a voltage controlled sequencer in my limited experience, this can then act as a source for the other modules until I can get other CV sources working.
I'm also keeping my eyes open for a reasonable MIDI/CV adaptor, as I've already got a decent MIDI keyboard. A proper CV keyboard will follow later.
The envelope generators (Or waveform generators as they are called) also look quite interesting needing only 7 transistors.
I've just hunted down my breadboards, so its time to start marshaling the necessary components and blow some dust off the scope and power supplies.
Magman |
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forbin
Joined: Jan 29, 2009 Posts: 120 Location: Fremantle, Australia
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Posted: Thu Feb 12, 2009 4:46 pm Post subject:
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Hi Magman
I am not sure how extensive your magazine collection but in one of the E&MM (really can't remember which, but i do have it home somewhere), there are some pictures of the WW Synth that somebody had built. It was in one of those columns which was people discussed their home system. I will see if i can dig it out during the weekend.
The actual design of the thing does have some clever features and one of the designers, Tim Orr, did have quite an association with EMS, the maker of the famous VCS3. Having said that a lot of things have moved on since 1973 and i am not sure how stable some of the design actually is. I have some concerns about the tracking and temperature stability.
Do you have, in your magazines, any errata for the designs? I only have a photocopy that i made in the early 80's from when i was at university. I can see a mistake in VCO3 straight away as the wiper from the rotary switch should go to the reset pin of IC2 not drive back into the first stage of the counter!
The design of the VCO3 is pretty clever and a more modern implementation is Ian Fritz's DoubleDeka see: http://www.bridechamber.com/bridechamber.com/F%20DoubleDeka.html |
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magman
Joined: Feb 04, 2009 Posts: 363 Location: Liverpool, UK
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Posted: Fri Feb 13, 2009 4:02 pm Post subject:
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Hi forbin, tanks for your comments.
I must admit to a very extensive magazine collection (I'm going to comment in the forums about this soon) and I have got at least the first 4 years of E&MM, but they're stored away in the loft for now, so I'll hunt down that article sometime in the near future.
I'm aware of the potential stability issues, but to be honest I would prefer to work with an unstable design to start with so that I can learn how big an issue it is in a real world situation. I doubt this will be the last synth project I work on (unless this one is so bad it drives me away ), so I'm going to play with various other designs along the way which will hopefully teach me the better ways to do things. I'm not just undertaking this project to build a synth, I want to have fun along the way and I really enjoy puzzles and learning new things.
I've had a scan in the following years worth of WW magazines and didn't spot any errata for the synth. I'm going to breadboard the design first anyway, so I can play with the connections as I build it to hunt down any deliberate mistakes. When I get it working, my next step will be to develop a PCB for it, which I'm planning to put the design up on the forums when I've got it working (notice the when, not if ).
Anyway, its time for me to get back re-discovering all of the components I've picked up over the years, as I've already dug out a couple of breadboards (I've also just found my developers box of E24 range carbon film resistors, all in separate labeled tubes).
Regards
Magman |
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Sine
Joined: Sep 10, 2007 Posts: 111 Location: Netherlands
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Posted: Fri Feb 13, 2009 4:50 pm Post subject:
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Interesting filter desing, the first I see built around a balanced modulator, looking at the circuit gives me nog clue how this thing works |
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forbin
Joined: Jan 29, 2009 Posts: 120 Location: Fremantle, Australia
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Posted: Sun Feb 15, 2009 5:35 am Post subject:
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hi Magman
The E&MM issue is the July 83 edition -- see page 66/67 -- It is an article about a synth built by Ron Berry and has some references to the Wireless World synth that he had built, including pictures. His main synth is Formant based -- much like my first one...
check out the pix at: http://www.ronberry.freeuk.com/page2.html
I am pretty sure that the first synth is the WW one... |
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magman
Joined: Feb 04, 2009 Posts: 363 Location: Liverpool, UK
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Posted: Sun Feb 15, 2009 6:37 am Post subject:
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hi forbin,
Thanks for the Ron Berry link, an interesting read.
I noticed Ron's comments about not being happy with his first synth - I suspect I'm going to find out about this 'unhappiness'.
I'm busy catalouging some of my other magazines at the moment to archive them in the loft, so I'll probably go hunting for that E&MM Article later this week. |
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magman
Joined: Feb 04, 2009 Posts: 363 Location: Liverpool, UK
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Posted: Sun Jun 02, 2013 1:51 pm Post subject:
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Anyone would think that you had been Googling for any comments about Wireless World, as this thread is definately getting on a bit.
Your posts are bordering on being spam, which would probably get you chucked off this forum quite quickly.
As it happens, my collection of Wireless World is complete from 1969 to 2011 and I have over 100 earlier issues going back to 1950 (I have over 630 Wireless World magazines and counting in my collection at present).
If your prices aren't silly, then I may still contact you to see if I can fill some of the earlier holes in my collection. We may even be able to do some exchanges.
Regards
Magman |
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go4thaudio
Joined: Jul 11, 2013 Posts: 1 Location: Apopka, FL
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forbin
Joined: Jan 29, 2009 Posts: 120 Location: Fremantle, Australia
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Posted: Wed Jul 17, 2013 9:33 pm Post subject:
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Very interesting... will have to finish that filter... love his CRO -- had ones like those in Science at high school! |
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Jetstuff
Joined: Nov 15, 2021 Posts: 4 Location: North Norfolk UK
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Posted: Mon Nov 15, 2021 3:12 am Post subject:
Back from the dead....? Subject description: Wireless World Synthesizer 1973 |
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Well.....magman, did you finish it?!
I'm just in the process of resurrecting mine....
A new link to the WW article:
http://www.keith-snook.info/wireless-world-magazine/Wireless-World-1973/Electronic%20sound%20Synthesizer.pdf
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AlanP
Joined: Mar 11, 2014 Posts: 746 Location: New Zealand
Audio files: 41
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Posted: Tue Nov 16, 2021 7:59 am Post subject:
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The VCF (page 11 of the link) looks very odd, don't think I have ever seen a 1495 chip in one! |
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Jetstuff
Joined: Nov 15, 2021 Posts: 4 Location: North Norfolk UK
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Posted: Tue Nov 16, 2021 9:03 am Post subject:
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Hi Alan,
That's one board that I have yet to build (VCF) !
Do you have any better (simple) schematic?
thanks |
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Ashleyjohn
Joined: Feb 18, 2023 Posts: 2 Location: Surrey
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Posted: Sat Feb 18, 2023 9:42 am Post subject:
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Hi,
New to this site, trying to fulfill a childhood ambition.
I am attempting to build this machine and I am going the KiCAD p.c.b. way, milling the boards with a CNC router.
I have put together a quick psu based on the LM7xxx regulators for now and I have built and got working the 6 step sequencer.
I have hit a wall, I can't get the VCO to work. The voltage control bit seems OK as I get a voltage change at oscillator input when I vary the bias, but thats it, the only thing that happens is that R18 gets very hot, which is not surprising as it has 28 volts across it.
I have been over the design countless times to no avail I am wondering if there is an error in the original schematic that was cleared up in a following magazine.
Any help would be greatly appreciated.
T.I.A
Ashley |
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Jetstuff
Joined: Nov 15, 2021 Posts: 4 Location: North Norfolk UK
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Jetstuff
Joined: Nov 15, 2021 Posts: 4 Location: North Norfolk UK
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Posted: Mon Feb 20, 2023 2:36 am Post subject:
It works.... Subject description: WW Synth 1973 |
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Got mine finished, working and sold at last.....! (never again)
https://youtu.be/PVHXPfvmhc4 |
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Ashleyjohn
Joined: Feb 18, 2023 Posts: 2 Location: Surrey
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Posted: Tue Feb 21, 2023 9:04 am Post subject:
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OK, that will teach me, the reason it would not fire up was that the bias potentiometer had a dry joint, and as I reused it, along with the attached wires, the fault followed me around |
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