Queensland Audio Club © 2019

2017 May - Simon and Kylin L.

Despite preceding messages of doom and gloom from the Bureau of Meteorology, we were greeted with beautiful sunny skies.

Kylin put on a sumptuous spread.

As seating was limited in Simon’s music room, our members made great use of the covered gazebo out the back.

 

Simon’s system is purely a DIY system which he is quite proud of and was happy QAC to share with fellow members on the day.

:It consists of:

Zeus Audio Class AB power amplifier designed and built by Simon.

250w into 8ohms both channels driven.

400w into 4ohms both channels driven.

More information about the amplifier build is available in this link.

http://www.stereo.net.au/forums/topic/119373-250400w-zeus-audio-class-ab-diy-designbuild/

AD1862 r2r Dac designed and built by Simon.

This uses an r2r type chip instead of newer delta sigma types. AD1862 is a 20bit chip.

More information about the DAC build is available in this link.

http://www.stereo.net.au/forums/topic/118498-new-ad1862-r2r-dac-build-and-compariison-to-off-shelf-dacs/

DIY Lightspeed passive attenuator.

Uses optocouplers for volume control.

A light source (led) controls the passive resistance in the attenuation circuit.

A simple circuit which doesn’t colour the sound as much as an active preamp. Only thing simpler is Alan E’s passive transformer pre we heard at the last meeting.

Custom Floor standing speakers.

Dual 8” woofers with mid/tweet/mid on top (MTMWW).

These were run as active in the last gtg at Simon’s place.

He has now changed to passive external crossovers in the pursuit of a bit more amplifier space.

Simon calls these his “Tsunami” speakers as they have a similar shape to a wave and are a deep blue (not because they cause destruction, although they are heavy).

Alan E brought his Musical Fidelity transport to use as a source.

 

Music played ranged from Strauss’s Also Sprach Zarathusa (you might know it as the opening theme to “2001: A Space Odyssey”) to the Beatles “Sgt. Peppers Lonely Hearts Band”.