In the 1990s, he paired with brother Masamichi as Maywa Denki and made their name creating a fantasy electrical world which pokes sly humour at modern life. Among their creations: a foetus doll that moves by pulling on an attached pistol, an extension cord shaped like a fish skeleton, a cage fitted with needles that drops into a pan of fish whenever a phone rings, and a toy vehicle that is activated by the swimming motion of fish in an attached container.

While his brother has since quit, Tosa continues to win plaudits for his odd blend of performance art and technology, and local audiences will get a taste of his zany appeal at concerts next month.

At a Paris show in 2004, he appeared with a set of self-playing drums, bass and guitar. Also in the array of remote-controlled 'instruments' were marimba shaped like flowers, shoes set up to produce tap-dance rhythms, and a fishbone-shaped xylophone which lit up a series of bulbs as it was played.

He isn't much of a dancer, his singing is pedestrian at best, and his songs don't carry any profound message, but audiences love the fun and energy of his shows.

'Most of my instruments are computer controlled, so it's actually very expensive karaoke.'

Tosa recently designed Seamoons, a pair of singing robots he describes as 'natural-born bad singers'. 'They have an artificial vocal cord, and never sing in tune. They're just very organic machines, similar to humans,' he says. 'So I find them very sexy.'

Tosa's steady rejection of logic has a madcap appeal. At the opening of his exhibition last week, he had guests cheering and swinging along as he performed a few numbers on his pachi-moku - a percussion device operated by electronic finger snappers.

'It's nice that we live in a common-sense world. But [I think] nonsense is the basic purpose of human beings,' he says.

As he sees it, life on Earth might not have existed if everything was logical. 'The first creature was born in the sea, then they colonised the skies and so on. There are so many incomprehensible processes.'

Fish are a recurring theme of his work and dreams, and Tosa likes to explore what role they play in his sub-conscious self.

Maywa Denki is named after his father's vacuum-tube company, which went bankrupt in 1979. 'I was only 13 years old at that time. It was a very sad moment. But I'm happy to be an artist instead.'

He earned a degree in mixed media arts at Tsukuba University, where he was influenced by the work of Dadaist artist Marcel Duchamp, especially his kinetic pieces. 'That was the period when I learned as much as I could about technology art, computer graphics, making machines.'

In 1993, the brothers revived Maywa Denki as an art unit, bringing their visions to the masses under the guise of electrical products. Treading the boundaries of art and commerce, they held 'product demonstrations' that were actually concerts and exhibitions.

Products are developed over periods ranging from a few months to three years. Most of Tosa's quirky instruments are used only during concerts and aren't for sale, but some gadgets, such as the fishing extension cord, are mass-produced.

Some may sneer at Tosa's designs as being ridiculous, but his work fills a niche for people fed up with the monotony of mass-produced appliances.

Maywa Denki began touring in 2001, and two years later received an award at the Arts Electronica Media Festival in Austria.

Tosa tries to challenge social ideas and mainstream habits with his works. For instance, while he embraces technology and techno music, he hopes to revive more primitive and direct acoustic sounds. Hence the pachi-moku - a percussion device with two hand-held electronic buttons that control the beats on a wood panel strapped on the back of the body. Tosa says he decided to build the gadget around a knocking motion because the action is one of the most simple forms of human communication. 'It's as basic as Morse code, it's either 0 or 1,' he says.

The device is also Tosa's way of reminding people of the energy of live sounds that are disappearing in an era of digital music and iPods.

'I hate iPod music. It's very poor quality. But [young people] go like, 'Yeah! I have many, many songs',' he says. 'Nowadays, we all [tout] big memory and big resolution. But I think there is another technology existing and I want to find it.'

His Edelweiss collection of machines, on the other hand, explore Japanese society's notions of beauty and preoccupation with materialism. Among them is a gadget called the 'Planter'. Tosa views the device - a cylinder of oil fitted with computer-controlled stirrers which send streams of liquid spilling over - as a metaphor for women's pursuit of beauty through cosmetics.

'I'm a man, so I'm interested in this phenomenon.What does cosmetics mean for women? I don't hate it, but I want to understand it as a desire of human beings,' he says.

It's hard to tell how profitable Tosa's business is. His Knockman series (a set of figurine-like instruments, each featuring a different knocking mechanism) are sold worldwide on toy websites.

Tosa declines to disclose figures, but says his main mission is to produce innovative material.

'When I was a child, my mother used to make one big pot of food and I would cry whenever I got just a small portion. My mother told me that if I wanted more, I would have to fight for it,' he says.

'I think this is the same with innovation. We can't just sit and wait [for it to come].'

Nonsense Machines: Naki, Agnes b. Librarie Galerie, 1/F, 18 Wing Fung St, Wan Chai, free. Inquiries: 2869 5505. Ends Jan 13

Maywa Denki Hong Kong Tour 2006, Oct 20 and 21, 8pm, HK City Hall, Edinburgh Place, Central. Inquiries: 2268 7323