MATRIXSYNTH: Practical Electronics

Showing posts with label Practical Electronics. Show all posts
Showing posts with label Practical Electronics. Show all posts

Tuesday, August 08, 2023

PE Clef String Ensemble 1978 Custom Kit-Built Analog Synth with mods

video upload by Vintage Keys Studio

PE = Practical Electronics. This is the first post to feature a demo of the Clef String Ensemble. You find a couple of pics of one in this post from 2012.

"Steve Christie (aka whatever silly-sounding name he makes up) demonstrates the PE Clef String Ensemble from 1978. With added functionality with a few simple modifications.

Here are the original plans for your perusal:

Filmed and Edited by Louisa Revolta
Recorded and Mixed by Steve Christie at Vintage Keys Studio"

Monday, May 22, 2023

Putting pins in the patch matrix of the RIGGYSYNTHI


"Time to get more sounds out of the RiggySynthi
and Support the museum here :-"

Tuesday, May 16, 2023

Frankenstein 70's DIY Synth Made From Various Electronic Magazine Articles - The RiggySynthi

video upload by LOOK MUM NO COMPUTER

"THE RIGGYSYNTHI made by peter! Let peter know what you think in the comments!"

Sunday, April 09, 2023

A Rare DIY 70's Magazine Synthesizer You Built Month By Month - P.E Synthesizer

video upload by LOOK MUM NO COMPUTER


Saturday, March 06, 2021

Making A Drum Machine From A 1970's Electronics Magazine



Thursday, February 25, 2021

Making A Drum Machine Twin T Drums - Practical Electronics January 1978


other issues here :-


Thursday, July 14, 2016

Practical Electronics Rhythm Generator For the Musician from Jan 1978

via @noyzelab

12 Switch Selected Rhythms

8 Percussion Voices

Curious what this sounded like. I've never seen one before. This is only the 20th Practical Electronics post on MATRIXSYNTH. That's out of over 140,000 posts.  Th others include the Minisonic and Minisonic 2, the PE Sound Synthesizer, and the the String Ensemble.  You'll find a few posts from Ken MacBeth and AM Synths AM8071 SnowFall Filter, which was "a traditional diode ladder low pass filter, similar to that in the EMS VCS3, Roland SH-3, System 100 and Practical Elctronics Minisonic 2."

Monday, May 23, 2016

Meet The Makers - Ken MacBeth

Published on May 23, 2016 sonicstate

"Scottish synthesizer maker Ken MacBeth talks to Sonicstate, about his roots and designing synthesizers."

Sunday, January 03, 2016

Blue PE Minisonic

via this auction

"Practical Electronics Minisonic analog synth.

These synths were constructed from schematics in the practical electronics magazine and are quite rare. This one uses the PCB that was available from the magazine.

This is being sold as spares or repair because VCO 1 is not functioning correctly, it can be heard but is not responding to the controls on the panel. VCO 2 is working as are the envelope generators. I am unable to test the filter and ring modulator because I have lost the patch cables. There is also a tear in one of the speakers.

I have copies of the magazine articles with schematics so this is probably and easy fix for someone with the right knowledge."

Friday, August 14, 2015

Rare Vintage Analog Synthesizer Keyboard of Unknown Origin

via this auction

If anyone knows more about this one feel free to comment (no need to login!). The look kind of reminds me of a Vermona '14 meets Baldwin Explorer.

Update: someone in the comments said it looks like a Minisonic 2. I think that might be it (see this post). The knob layout starting with the two large knobs on right match.

The following is the description from the auction. This is not a modular so obviously ignore that bit.

"Rare VINTAGE Analogue MODULAR SYNTHESIZER similar To ''PAIA 2720 1970s**mid to late 70s presented in teak coloured angular upright case with nicely hinged metal upper, Measures 83 cms LENGTH/ .31 cms DEPTH/WITH AN OVERALL HEIGHT OF 21cms (approx) 29main keys output socet to front /headphone socket to rear comes with mains supply lead which is 3 pin 220/240 volts.OFFERED IN V.GOOD CONDITION THROUGHOUT /Mains tested and ights up correctly when switched on!all components appear original and intact and solder seems sound.
Features 27 Rotational knobs,18 push set buttons 2 large adjustable Frequency buttons, 2 small trig buttons.


OSC MODE{+E-1/-E-1/+E-2}

Wednesday, May 28, 2014

Vintage Minisonic Synthesizer

via this auction

See the Minisonic channel for more.

Thursday, April 03, 2014

Practical Electronics P.E. Sound Synthesiser

via this auction

Here's something you don't see every day. A completed Practical Electronics P.E. Sound Synthesiser. There is only one previous post with an image of the Practical Electronics magazine cover here. See the Practical Electronics channel for more.

"1973 Practical Electronics P.E. Sound Synthesiser

This is a modular analogue synthesiser and controller keyboard (actually a second modular synth in its own right) that was built from a design published in 1973 in the UK magazine Practical Electronics. This is the only one I have ever seen and is possibly the only surviving example.

The design was by G.D Shaw who later designed the Minisonic synthesiser. I think it is fair to say that the design was greatly influenced by the EMS Synthi in both functionality and controls (and sound I have heard). It was also the first magazine DIY synth published in the UK at least.

The Synthesiser is in two parts - a rack unit with the main sound modules (oscillators, amplifiers, tone filters, sample & hold, ring modulator, spring reverb, meter etc) and a separate controller keyboard with extra functionality (oscillator, VCF etc)

This example (the main rack unit) was built exactly to the published specification as far as I can tell and was completed to a very high standard (I would describe it as 'laboratory grade' construction). It features hand wired circuit boards (as per the published design and layouts) that plug in to a 'backplane' so it is a truly modular synth. All patching is done by 2mm plugs on the front panel, original patch cables are included.

The rack unit has a good range of modules included. Here is a complete list -

Stabilised Power Supply
2 x Input Amplifiers
2 x V.C. Modulators (Ramp & Pulse Generators)
2 x V.C. Oscillators (Triangle & Square Waves)
2 x Output Amplifiers
Reverberation Amplifier & Spring Line
Ring Modulator
2-Band Tone Filter
Envelope Shaper (Incl. Trapezoid)
Noise Generator
Sample & Hold
Differential Amplifier
Analogue Meter

Quite a good specification!

The keyboard controller design was modified somewhat by the original builder to incorporate extra features (VCF, Joystick controller and extra oscillator I think) but crucially this part of the project was never completed, though all the parts are there, including completed PCB's, control panel, keybed, wooden casing and design notes etc.

The Synthesiser comes with full original documentation, including a full set of original magazines, all instructions supplied with the original kit parts, also many handwritten notes by the original builder detailing his modifications. Also included is a box full of many original spare components, patch cables, interface cable (for the keyboard I think) and other parts.

I bought this several years ago from the original constructor, I was told then that the main rack was fully functioning but had not been used for a long time, and that the keyboard was unfinished. Preliminary tests at the time showed that it powered up and some of the modules worked, but it would need some attention (I suspect the backplane plugs and sockets all need a good clean). I put it on my list of projects to do, but unfortunately I have never been able to get around to it. I have therefore reluctantly decided to pass it on to someone who can, as it is unlikely that I will ever have the time now. So, be prepared, this instrument will require a bit of time and effort to restore it to full operation. At the very least, I would recommend a complete inspection and overhaul of the main unit by a professional synth tech.

I imagine that this unit will appeal mainly to collectors, or those interested in the DIY synths of the 70's and 80's (as I am) I believe it has the potential to compete with an instrument like the EMS VCS3, which it was clearly inspired by.

Note that there is now very little information out there about this design. I have never seen another complete unit anywhere online or on youtube for example, apart from the original designers website (which is now sadly gone) and a couple of brief mentions on Matrixsynth from others who had built them (but no mention if the units still exist)

I think there is a fair chance that this may be the only surviving example, in which case you are looking at a truly unique piece of synthesiser history. I would be very interested to hear from anyone who has one though.

This is a big, heavy item and will require careful packing and shipping arrangements. I will ship worldwide, exact cost to be determined at the time and depending on location, but I expect it could cost up to £250 to ship to some locations (but probably a lot less, I will only charge at cost) I have put an extended dispatch time on this listing just so I have plenty of time to pack and arrange things properly, but I will try to send it at the earliest opportunity. Local pickup is also possible by arrangement.

Please Check out my other items! and Thanks for looking."

Monday, December 16, 2013

Ken MacBeth Elements....?

Published on Dec 16, 2013 macbethsynthesizers·97 videos

"I've been experimenting with Diode Ladder Filters.......I've attemted to design something that is not harsh or RaWkus when it hits a resonant peak! I made one awful one, but learnt from it- here are two- one based on the English Magazine from the seventies- the Minisonic Diode Ladder, and secondly, loosly based around the rather fantastic Roland System 100 Diode Ladder filter! the end of a long few days- I present!..........apologies for the low volume audio here.......but you'll get the idea, none the less!"

Monday, October 21, 2013

AMSynths Snowfall v Mirage Filters

Published on Oct 21, 2013

AM8071 SnowFall Filter
"This module is a traditional diode ladder low pass filter, similar to that in the EMS VCS3, Roland SH-3, System 100 and Practical Elctronics Minisonic 2. The filter has a 4-pole ladder with an 18dB like response, thanks to the unique characteristics of diodes..."

AM8328 The Mirage Filter
"This module is based around the CEM3328 4-pole Low Pass Filter chip that was released in 1984, as one of the last filter chips and with some great features. It has differential signal inputs, an accurate exponential scale over 14 octaves and voltage controlled resonance. It has a unqiue feature, the signal level is automatically increased as the resonance goes up, thereby avoiding the usual signal level dropping off as resonance comes in. The CEM3328 was late onto the analog stage, just before digital filters appeared, so it only made it into the BIT01 and Ensoniq Mirage (and a few drum machines). So this chip has never really seen action, and was never under analog pot control, just lonely digital paranmeter access! In the Mirage it was not even allowed to oscillate…..We just love giving it a new lease of life in a new analog module!"

Friday, August 10, 2012

Practical Electronics String Ensemble

via this auction

"These were sold in kit for in 1978 in the Practical electronics magazine. Boards were made by CLEF electronics who made various kit synths

Being sold as a restoration project as there are some parts missing and it does not function correctly. From what i can see the only parts missing are the 2 wooden end pieces that fill the gaps at the ends of the keys, a couple of slider caps, slider shaft missing, 1 x i.c on the chorus board is corroded and pins broke when i tried to remove from the socket. Other than that it looks complete

The mains cable wants replacing as it has got very worn, for safety this must be changed. I have powered on and the power light comes on, connected to an amp and the keys trigger some sounds but all a bit hit and miss on triggering. This will be down to key contacts being dirty i think.

nice little project as i am sure all of the components are standard and easily available now"

Sunday, March 18, 2012

Practical Electronics Minisonic

via this auction

"Practical Electronics mini sonic semi modular analog synth. This is being sold as spares or repair. It is making sounds, the vco's are changing pitch using the stylus type keyboard (no stylus - just using the wire) but as I can only find one patch cable I am unable to fully test it.

The synth has 2 VCO'S, 2 EG'S, 2 VCA'S, Voltage controlled filter with resonance, noise generator and ring mod (yes you can sound like a dalek)
I should have photocopies of the magazine articles used to construct the synth somewhere and will include them if I can find them, it's readily available one the net if not."

Friday, September 23, 2011

AM8071 Snow Fall VCF

via AMSynths

"This module is a traditional diode ladder low pass filter similar to that in the EMS VCS3, Roland SH-3, System 100 and the PE Minisonic 2. The filter has a 4-pole ladder with an 18dB like response, thanks to the characteristics of diodes. A fifth pole can be switched in to give a steeper 24dB response using the Slope switch. The control voltages can be smoothed out using the Lag switch, to give a more fluid modulation.

The filter has adjustable Cutoff Frequency and Resonance, along with a resonance CV input, 2x Signal inputs and 2x Frequency Cutoff CV inputs. The panel design is a mix of rotary and slide potentiometers. The filter was developed during the heavy snowfalls across the UK in February 2010, hence the name."

via the AMSynths blog: "Back in the late Winter of 2009/2010 there were heavy snow falls in south east England for the first time in many years. During this "white out" I designed a diode ladder voltage controlled filter similar to the ones that appeared in a number of analog synths in the 1970's, and named this new module "Snow Fall". In 2009 I had already built a number of prototype 4-pole diode filters from the EMS VCS3, Roland SH-3 and the Practical Electronics Minisonic 2. I improved the designs with modern components and added a fifth pole and slew delay on the CV input. This AM8071 protptype was very sucessful and delivered a great sounding and flexible VCF.

During Summer of 2011 the prototype was worked up into a production design using the new AMSynths panel design which has a mix of rotary and slide pots, with momentary push buttons. The production units were launched on 20 September 2011 and this EuorRack module is available to purchase from AMSynths web site."

Sunday, March 27, 2011

Snow Fall - EMS VCS3 Filter Clone

via AMSynths

AM8071 Module - "Snowfall" Diode Low Pass Filter

"During the exceptionally snowy weeks of early 2010 I built a redesigned version of this classic filter which was used in the EMS VCS3 and AKS synthesizers in the 1970’s. With snow falling and the wonderful bubbly sound of the filter, I named this module - Snow Fall. It was a 4-pole diode ladder low pass filter using all discrete and rather old components. The Roland SH-3 filter (AM8003) and PE Minisonic 2 (AM8050) filters are close copies of this legendary design.

EMS originally (in 1970) described the filter as Low Pass and with a cutoff rate 12dB for the first octave and then 18dB per octave thereafter, with band pass filter response at medium Resonance levels and a maximum Q of 20. From early 1974 EMS updated the filter with an extra capacitor at the base of the diode ladder to provide a steeper 24dB per octave response, this appears to have changed the character of the filter. The filter frequency response is stated as 5Hz to 10kHz.

In terms of electronic design the standard filter is 4-pole but the characteristics of diode ladders makes this sound more like 18dB, and the 24dB version is really 5-pole. No matter, the filter sounds fantastic....

Visit the AMsynths web site for the full story here..." You will find samples there as well.
Be sure to see the rest of AMSynths for more DIY clones and projects.

Saturday, March 19, 2011

1970s Practical Electronics - P.E. Sound Synthesizer

via this auction & this auction

Top: "This listing is for three issues of Practical Electronics magazine from February 1973, July 1973 and Sept 1973. They contain parts one, six, & eight respectively of this fairly extensive project by designer G.D. Shaw. Ultimately it should be possible to source the missing / follow-on issues from other ebay listings.

Part 1 contains the introduction, specification, block diagram and pictures of the prototype / finished product.

Part 6 details the tone control, and gives details on setting up an experimental sound studio.

Part 8 covers the envelope shaper (a strip-board overlay is included)."

Bottom: "This listing is for two issues of Practical Electronics magazine from November / December 1974. They contain the first two articles of the series on the PE Minisonic Synth by designer G.D. Shaw. It should be possible to source the follow-on issues from other ebay listings.

Article 1 contains the introduction, specification, block diagram and housing design, while article 2 details the V.C.O, V.C.F, and envelope shaper / V.C.A"

Monday, November 23, 2009

PE Minisonic Serial Number 001

via Julian

"The inventor of the Minisonic (Doug Shaw) tells me: 'Serial No.001 Minisonic must have been the first to have been made under license by SMS (Synthesiser Music Services) Ltd., from their base in Holland Park, London, and probably dates to late 1974- early 1975.'"

You can find more pics here. Be sure to also scroll up when you get there for more info on the Minisonic. The label below will take you to prior posts here as well.


Patch n Tweak
Switched On Make Synthesizer Evolution Vintage Synthesizers Creating Sound Fundlementals of Synthesizer Programming Kraftwerk

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