The Clef Products String Ensemble

Here we come with another collaboration from our friend Jeffrey Jones. In this case he talk about the Clef Products String Ensemble a.k.a. PE String Ensemble

"The construction details for the String Ensemble were published in Practical Electronics in 1978. It was designed as a version of the 'string machines' or orchestral synthesizers that were available at the time to produce a sound which would simulate the whole section of an orchestra. It was designed by Alan Boothman of Clef Products who also designed the Joanna and Band Box. The kit was supplied by Clef Products although Maplin also sold a kit.

The design was four octave based on a top octave generator chip, each note being further divided down by two several times to cover the range. Each note had a separate divide by two chip. The signal was then sent to a diode gate. Each note of the keyboard had a diode gate switch which simultaneously switched four octaves of the note through to the signal processing circuit when a key was pressed. This produced a harmonically very rich signal. A separate diode gate for each note also meant that the instrument was polyphonic. 

The sound then went through a dual delay line with two slow oscillators running a different speeds controlling the delay to give a constantly shifting phase to give the effect of several instruments playing together. Finally the signal was sent to a filter circuit which had switchable filtering to simulate different sections of the orchestra. 

There were filters for high and low strings and also brass and woodwind. These could be mixed together using sliders in any proportion. There were also sliders for adjusting the attack and decay. Finally the keyboard could be split to give a low, medium and high octave setting on the bottom third of the keyboard to accompany the other voices.

The sound was superb, especially considering it used purely electronic means to generate the notes. The top strings were especially rich and vibrant sounding. There was also a socket for the provision of a swell pedal to add extra feeling and realism to the sound.

The kit supplied by Clef was up to their usual high standard. The circuits were printed with the component positions on to make assembly easier and the wiring connections between the circuit boards were also marked. Everything needed to build the kit was available including the keyboard, cabinet and a printed front panel to give a professional appearance.

The building of the kit was generally fairly straightforward with just two exceptions:

The diode gate of each note consisted of twenty components which had to be fitted in the space allowed between each note. To achieve this some components were stacked on top of each other which made soldering quite difficult. Also the fact that each note needed twenty components meant that there were a total of nearly a thousand components just for the diode gates. This was a rather monotonous task.

The other problem was that each diode gate needed four buses to supply it requiring a total of nearly two hundred soldered connections. This was made more manageable by the special enamelled wire supplied with the kit in which the insulation melted upon soldering.

Although there was a lot of work involved in constructing the kit the result was well worth the effort. It worked first time with no problems. In the nearly 35 years which I have had it I have had only two problems with it, a smoothing capacitor failed and one of the top octave generator chips also failed.

I think that this was one of the best electronic instrument kits ever produced but despite this I have never seen any other mention of it on the internet and have never seen one for sale on ebay or anywhere else. I would be very interested to know if there are any other owners (past and present) out there."

Jeff not only made the pictures from his own instrument that you see here, he also he took sound samples so everyone can hear the instrument in its fullness (or you could split into individual files and load it into a sampler to play with it), the sound samples are recordings of all of the C, E and G notes of the top strings covering the full keyboard.

You can hear and download the sound samples here:

Clef Products (Electronics) Ltd.

In the next entries I will be publishing some information about Clef Products Ltd. (sometimes called Clef Electronics). This company had very interesting kits, some of them were ahead of their time, but badly marketed. I have a couple previous post about Clef, look for the Clef tag.

I've found this web with profuse information about Clef and the kits they were selling at that time:
http://audiotools.com/en_mi_dead_b.html

In conversation with our friend Jeffrey Jones about Clef, he recalls:

"As regards Clef I have met Alan Boothman twice, once at an electronics exhibition where he had a stand displaying the piano and string ensemble, and once when I went to his premises to pick up the cabinet for the piano. He was always very friendly and helpful. I also had contact from someone who used to work at Clef. He was advertising to buy a String Ensemble about two years ago. I contacted him and he gave me a valuable insight into the company which I can share with you."
Sure we will enjoy what you have to told us Jeff! He also sent this old Clef two-page catalog pictured here:

I made this chronological list of Clef instruments/kits:

• 1972 - PE Electronic Piano (Practical Electronics, sep 1972 to jan 1973)
• 1975 - Joanna (PE Joanna - Practical Electronics, may to sept 1975, may 1977)
• 1976 - Sound Design (updated Joanna) (Practical Electronics, mar 1976 pg.215?)
• 1978 - String Ensemble (PE String Ensemble - Practical Electronics, mar to july 1978)
• 1978 - Electronic Piano (88 keys, 72 keys and 'Stage Piano', three versions of an updated Joanna)
• 1979 - Master Rhythm (PE Master Rhythm - Practical Electronics, dec 1980 to jan 1981)
• 1979 - Band-Box (PE Bandbox - Practical Electronics, nov 1981to feb 1982)
• 1982 - Microsynth (aka. uSynth and later B30 Microsynth - Practical Electronics, jun to aug 1982)
• 1984 - PDSG

I don't know if Clef had more than those instruments/kits mentioned here. From all of it, there are so little info on the web, so, with the help from some friends, in the following posts we will be talking about some of this rare instruments.

Minisonic music missed

Pages ahead, from my previous post, I've found this ad with PE Minisonic kits, parts, pcb's AND the "Symbiosis" cassette by Malcolm Pointon.

The Minisonic series of articles was published in Practical Electronic magazine between november 1974 and march 1975 issues, by a man named G. D. Shaw. I don't have any of these magazines, but I've saw the scans of this synth in the Anders Sponton's Cloned Analog Gear web, but the scan of Anders don't came from the magazines, is from a book published with all the constructive articles of the Minisonic and other things.

Judging by this ad, it seems that in the last article of the Minisonic was offered to the readers a companion tape with the music created with this synth.

I must admit that I never heard about Mr. Malcolm Pointon never in my life, then Wikipedia came to help me and I've learned about the very tragic life of this man. Obviously, I didn't know their music. I think it will be very interesting to hear this cassette, in first place because is related with the main role of this blog (electronic arts-electronic instruments) and then because it could be the only "electronic work" of this man demoing a very particular instrument.

I call all the people out there, mainly to the UK people, to search in the old pile of cassettes looking for this gem... and please share with us!
 
For more information about the Minisonic (and the PE Synthesiser) you could visit the Julian Bunn webpages about it, here and here. Very nteresting is the Minisonic serial number 001 (at the bottom of this page) maybe this was the used by Malcolm Pointon?
 
At the end, I want to show an alternative casing for the Minisonic with keyboard in this ad by Phonosonic, in this same magazine (also pay attention to the alternative casing for the PE Synthesiser and the kits for the PE Joanna piano that I've wrote before) .

Joanna, the "shE-Piano"

Has been a while since the last post, to reward the curious visitor here this time I bring a piano. There are many builders of synthesizers, a bunch of organ builders ... but how many people have built a piano? And I'm talking about e-pianos, of course.

Reviewing my old magazines I found in Practical Electronics a series of articles to build the "Joanna" a very complete electronic piano for its time. The designer was a man named A. J. Boothman, I believe this man had a sort of relationship with the CLEF company, and certainly had a kit available through this company (although there were other companies offering it).

I did not have the opportunity to see the full series of articles, this was published between May and September 1975 and I only possess August and September. Judging by these two parts, it seems to me that was well designed and really well tested because at the end the author makes some recommendations on amps and speakers to obtain a good sound, making references to the equipment he used.

I really like to see the full serie of articles to have a further insight on this instrument, because how many people you know, that had made an e-piano? And if we could get some sound samples that would be really great! The interesting thing here is an e-piano that sound... 'electronic', because if you want more real pianos (and cheap), the samplers are the easy ways. Enjoy the pictures.