Kaisatsuko - Electric original wheel rubbed stringed instrument

is a two-string electric rubbed instrument that Yuichi Onoue developed in 2003. It has a shape like a eastern spike fiddle, but there is a spinning wheel near the bridge instead of playing with a bow which rubs the strings to make a sustained sound. It can be said that it is a cousin of western Hurdy-Gurdy and eastern spike fiddle. The translation of the word is as follows:
Kai = Rotation , Satsu = Rub , Ko = Oriental fiddle

About the rotation mechanism, when the shaft which through the middle of the body side is turned by handle, the rotation is transmitted to another shaft that is in a 90 degree relationship by a miter gear, and that shaft is attached the wheel which rubs the strings to make a sound.
To see what the performances and sounds of the Kaisatsuko are like, see this video. 'Within You Without You' the Beatles cover by Sanpin(Onoue and Yuzo Hisada's handmade percussion)


This Kaisatsuko is the second one produced in 2004. Since then, as of 2019, this one has been used in various scenes such as live shows and recordings at a pace of about 2 to 3 per month. As an aside, the first one produced in 2003 has poor quality at the prototype level and has not been used since the following year. In addition, there is also a state of emphasis on performance activities, the third one has not been produced as of 2019.



Miter Gear and Wheel




Because I had not made a design drawing of Kaisatsuko, I wrote the dimensions of each part on the photo, including the meaning of my memorandum.

Shim under the end of neck

Insert a 30 mm x 20 mm x 0.4 mm thin shim under the end of neck to slightly angle the neck. As a result, the sound of the high position gets very well.


Body: Agathis 300mm x 100mm x 15mm → What is sold as a nameplate in Tokyu Hands(DIY shop in Japan).
Neck: Tamo(Japanese ash) 15mm x 30mm x 1 m → This is also purchased from Tokyu Hands.
Privately, I was not particular about the material and selected it appropriately.


Pick-up is functionally same as the electromagnetic pickup used for electric guitars. About 0.1 mm coated wire is wound around the bobbin of the sewing machine. I wound this by using a sewing machine. The iron rod is passed through to make a pole piece, and a ferrite magnet is placed below.

Nylon Wheel
This wheel is used for such as kitchen wagons. You can buy it for less than 200 yen at a DIY shop. Outer diameter 32φ, inner diameter 5φ. Since nylon thread is sometimes used for the bow part of rubbed string instruments used in folk music, so I applied a 'nylon' wheel for rubbing the strings. When playing, apply the rosin of the violin to this.

Miter Gear

5φ Stainless Shaft

Brass Handle

Shaft Stopper

Shaft Bush

Bridge part
6φ long screw → pillar tighten to the body with a hex nut.
6φ wing nut → Fasten the aluminum plate. And adjust its height.
Aluminum plate 80mm * 10mm * 2mm
Top → stainless 2φ steel rod

Using pegs of a Les Paul type electric guitar. As an aside, these pegs are the remnant of my broken 1st guitar (purchased in 1984).

Electric wiring

It is connected two pickups in parallel. The pickup on the two string side attaches a Volume of about 100 KΩ in series. This volume is put only on the 2nd string side in order to change the volume balance of 1st string and 2nd string. The overall volume control is done with the foot using the general purpose foot volume.

Strings, Tuning

Using steel strings for electric guitar. 1st string (009) and 2nd strings (011) Because electromagnetic pickups are used, nylon strings can not be used . As for tuning, since I have been a guitar player from the beginning, so I am using 4th interval tuning such as 2nd:1st = A: D, or sometimes 2nd:1st=G: C or B: E. And I rarely use 5th interval tuning.

Playing style

・2nd string for drone、1st string for melody→example
・playing chord→example
・tremolo(Move the handle with vibrate)→example

Effect Processor

Kaisatsuko is processed into various tones by using the KORG AX1G multi-effect processor. This model includes not only distortion, compressor, EQ, delay, reverb as well as conventional ones, but also has very unique effects like 'DRONE' that produces a resonance string effect, 'VOICE' that produces an uttering effect, 'FILTER' that produces an analog synthtic sound and so on. For me, this AX1G is very important thing that can be said to be part of an instrument rather than effect processor. By the way, I am also a developer (in charge of DSP programming and sound creation) of AX1G (released in 1998).


I would like to introduce you various applications of the Kaisatsuko in various musical forms so far. As I described on "Effect Processor" , Please pay attention to various tones, too.

First of all, here is Wananabani-en experimental rock/pop instrumental band who includes Onoue's handmade instrument + bass × 2 + drums. The song is my "Still Life" written by using Kaisatsuko. As this is an electric, it is possible to process the timbre by effect processor and it can cope with a large sound.

This is a power pop original song "Kara-Age" by Wananabani-en. The tone is also processed by the effect processor.

Here is with distinguished Koto(Japanese stringed musical instrument) player Hiroe Morikawa. It would be the collaboration of the most famous vs unknown Japanese musical instrument.

With Leo Duplex's Lap top PC playing. Kaisatsuko is processed very special infinete ascend pitch shift effect. Very spacey.

Here is Sanpin again, and the song is called "Kaisatsu Blues". Of course, I wrote this song by using Kaisatsuko. We play in full power in the middle.

This footage is with electric-acoustic hybrid drum duo called Asymtote - byTakeshi Minami and Hiroaki Machida. Gradually swell and develop a very heavy and psychedelic performance.

With Yukie Sato who is rock/folk singer active in both Korea and Japan, and our friend Koichiro Yamamoto (perc). Live at Busan, Korea.

more Kaisatsuko playlist on youtube

People who made the Kaisatsuko by imitation

Acoustic Kaisatsuko made by Jeff Pollack. Nice!

These footage are from Russia? Sound and playing is......umm... But I am so delight that they made this. 

External Links

Onoue Torigoya Sound(Yuichi Onoue's official web site)
Odd Music
Noise Junk
Make Magazine
Make Magazine(Japan)
学研大人の科学 エレキ特集号(回擦胡が紹介されている)
米本実著"楽しい電子楽器 自作のすすめ"(回擦胡が紹介されている)




コメントを投稿するには、 ログイン または 会員登録 をする必要があります。