Music

Brooke Clarke 2003 - 2019

DX7
TX802
Yahama MS101 II Monitor Speaker
Roland Cube 15x
Theremin
Linnstrument
Yamaha CSF-TA Guitar
Related
    Korg M-20 Mini
    Korg SQ-1
    Pocket Operators by Teenage Engineering
    Gecho Loopsynth
    DIY Synthesizer
     Home Theater - 7.1 Surround Sound
Links

Yamaha DX7 II Analog Music Synthesizer

The DX7 (Wiki) uses a very sophisticated analog mixing scheme to make very complex and pleasant to humans sounds.  It's probably the last of the analog electronic music instruments.

In addition to equal temperament tuning there were other tunings built in:
Pythagorean  
Werckmeister 
Kirnberger 
Vallotti & Young                 
1/4 Shifted equal  
1/4 Tone              
1/8 Tone

Patents

3577084 (Google)Computer Sound Generator May 4 1971 Singer-General Precision 327/107; 84/659; 327/134; 341/147; 377/51; 377/112; 984/389; 984/DIG1
3696201 (Google) Digital Organ System 84/648; 84/659; 84/660; 984/382; 984/DIG1 (Wurlitzer) -
4018121 (Google) Method of synthesizing a musical sound Filed: May 2, 1975, Pub: April 19, 1977 John M. Chowning 84/696; 84/101; 84/659; 984/309; 984/324; 984/389; 984/DIG1 - Basis of the Yamaha DX-7 Synthesizer.
Patents calling 4018121 -
4813326 Method and apparatus for synthesizing music tones with high harmonic content, Yamaha, Filed: Jul 16, 1984, Pub:  - Fig 22 block diagram of an operator
4922795 Tone signal forming device, Yamaha, Filed: Nov 17, 1987 -
5025702 Electronic musical instrument employing time-sharing frequency modulation and variable control of harmonics,Yamaha, Filed: Jul 3, 1975, Jun 25, 1991 - FM synth (filed a month after Chowning)
5191161 Electronic musical instrument including waveshape memory and modifiable address control, Yamaha, Filed: Jul 3, 1975, Pub: Mar 2, 1993 - variable color with same pitch from table entries.

DX-7 II + add on

I had one of these synthesizers.  After adding on a small PCB (Grey Matter E! ?) the capabilities were greatly increased and not only could it be controlled by my Radio Shack Color Computer it also could remember an arrangement.  I think it had a complex rendition of "The Entertainer" built-in.  If you know the maker and/or model number of this add on board let me know.
Wave of the Future - History of Chowning's development.

With the introduction of micro controllers and home computers the age of digital sampling (Wiki) allowed the production of sound that matched that of an actual instrument.  The samples could be played back at different speeds and modified using the same signal processing methods used for analog music synthesizers.  So analog synths fell out of favor and the digital synths took over.

But in the late 1990s an interest in analog synths came back.  Part of this is related to the availability of Eurorack (Wiki: Doepfer_A-100)modules, most of which are reasonably priced.  PAiA (home, Wiki) has been making low cost music synth modules since 1967 and still offers them.

Yamaha TX802

Is a keyless rack mount box version of the DX7.  Requires external MIDI controller.
YouTube: Yamaha TX802 Demo - Yamaha TX802 - A few performance patches -

Dave Benson's DX7 Page - many documents

YouTube, cellarseer: Yamaha TX802 Service Mode - walks through the 8+9+On mode.

Fig 1
Hold number pad 8 and 9 while turning on power.
Firmware V1.0 22-APR-87
Yamaha TX802
Fig 2 Op Sys chip in upper right
just below TX802, marked: XB223 [8]
New chip marked: TX802, XB224 OS V 1.5
-------My ERROR------
I installed the V1.5 chip at the top left, but it should have been
installed in the upper left.

Yamaha TX802
Fig 3 with Ver 1.5 op sys:
The top LCD row is all black dots.
-------My ERROR------
Yamaha TX802

Yahama MS101 II Monitor Speaker

Got this to go with the Korg M-20, but also used it with the Yamaha DX-7 (borrowed) and TX802.

Fig 1
Yahama MS101
                    II Monitor Speaker
Fig 2
Yahama MS101
                    II Monitor Speaker

Roland Cube 15x

Found this on eBay for a good price.  Poor packaging, but these seem to be made to take a beating and keep on ticking.

Fig 1 Styrofoam peanuts (crushed) and popped
air pillows inside box, should have used bubble wrap.
See Packing for shipment.
Roland Cube
                    15x Speaker
Fig 2 Front
Roland Cube
                    15x Speaker
Fig 3 Back  Controls are for Guitar effects (Wiki)
Roland Cube
                    15x Speaker

Theremin (Wiki) (my Geek Stuff page)

There is an interesting Video about Leon Theremin: Theremin: An Electronic Odyssey 1993 (IMDB, Netflix)
He's the father of electronic music.  That's to say he made the first electronic music instrument.  Moog (Wiki) designed a number of Theremins starting in high school.  The Beach Boys (Wiki) used a Tannerin (Wiki) (easier to use than the Theremin), for Good Vibrations. PAiA and Korg make Theremins.

TED Talks:  Pamelia Kurstin plays the theremin - her's is a left handed unit, i.e. she uses her left hand for pitch control.  She makes the point that when playing you must keep your body very still, even to the point of not breathing during a low note.

The problem is most people can not move their hand to a fixed position in 3D space and hold it there, so it's a difficult instrument to master.

Linnstrument

This introduced me to expressive music controllers.  Each key is sensitive for pressure (Z axis), pitch bend (x axis) and a third parameter like filter setting (y axis) allowing for very nuanced performance.

There are a number of other expressive controllers such as:
The Eigenharp family of instruments (Wiki) from EigenLabs - patent 8934088 Sound-creation interface - uses a custom switch that has variable outputs for x, y and z based on modulating a light beam or using a breath controller.
These allow performing electronic instruments with the same expression as actual instruments, fantastic!

Yamaha CSF-TA Guitar

At first glance this appears to be an acoustic guitar.  But it has an internal DSP based (Wiki) processor that adds special effects then used a force actuator to shake the sound board so it acts as a loudspeaker.

7812243 Stringed instrument with embedded DSP modeling for modeling acoustic stringed instruments, Peter J. Celi,Michel A. Doidic, Marcus Ryle, Yamaha Guitar Group Inc, 2010-10-12 - The actuator might make use of
Magnetostrictive material, i.e. be something like the Sound Bug.

Related

Korg MS-20 Mini Synthesizer

While looking for an analog music synthesizer that might be used with the Linnstrument came across the 1978 MS-20 (Wiki) and the modern MS-20 Mini version that includes MIDI (Wiki).
Note that the M-20 is a monophonic (one note at a time) synth and so is not suitable for use with the Linnstrument.

Korg SQ-1 Analog Sequencer
Pocket Operators by Teenage Engineering PO-16 Factory "lead synthesizer for keys melodies. sequencer with parameter locks, play styles and punch-in effects. pocket operators are small, ultra portable music devices." - User Guide - pdf
Fig 1
Pocket Operators
                    by Teenage Engineering PO-16 Factory

Very capable device, but has a steep learning curve.
Note there are LEDs above each button 2 and 12 are on in this photo.

Gecho Loopsynth
DIY Synthesizer
Home Theater - 7.1 Surround Sound
Sound Powered Telephones & Early Loudspeakers
Audio

Links

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Page created 22 June 2003.