Bright spark in finals for low volume distortion amp

Soft rock . . . Karl Brinsdon (17) is a finalist in the Bright Sparks competition for his invention: an amplifier which allows guitarists to produce distorted sound at lower volumes. PHOTO: SHAWN MCAVINUE

Dunedin pupil Karl Brinsdon is amped about being named a finalist in a national competition for young inventors.

A judging panel selected the Mosgiel teenager as a finalist for the 20th Bright Sparks competition – New Zealand’s longest running national competition for inventors, which is open to intermediate and secondary school pupils.

He was “surprised and happy” when he told he was a finalist last week.

The Logan Park High School pupil was selected for his project Varying Valve Voltage, an amplifier which allows guitarists to produce valve sound at lower volumes.

A standard amplifier sounds “great” when the volume was cranked up.

But the distorted sound often sparked noise complaints.

A distorted sound could only be achieved from an amp at a loud volume but his amp could produce it at a lower volume.

Amps turned up to produce a distorted sound was part of a rock music, exemplified by guitarists such as Brian May, of Queen.

He used May’s amplifier, the Vox AC30, as inspiration for his invention.

He had invented an amplifier which would allow more guitarists to get a sound they wanted.

“There are a lot of guys playing at home and they want that sound but they have neighbours or families not too keen on the noise.”

He had used the amplifier when recording music but had not used it during a live performance, despite it being capable.

“It’s loud enough and the distortion is at a level that will keep the sound guy happy.”

An interest in electronics was a byproduct of his passion for music.

The most challenging part of the project was building the amp’s circuit board, which included drilling 50 holes.

The 23 finalists have been invited to an award ceremony, where the supreme winner would be announced, in Auckland on November 1.

The competition organisers had paid for his flights and accommodation so he could attend the ceremony.

The project had won him accolades before.

The invention won the Dodd-Walls Centre for Research excellence award for physics related projects and an Aurora Award for excellence in energy research at the Science and Technology Fair in Dunedin in August.