E-MU Audity 2000 ROM Demos

YouTube Uploaded by HarryMatic on Aug 27, 2011
Channel moved to Harry Axten

"The four built in demo tracks of the E-MU Audity 2000 Sound Module from 1999. The Audity 2000 came before the well known Proteus 2000 line and it's many spin-offs, so it shares the same synthesis architecture. My unit has the Version 2 ROM which offers 64 voice polyphony rather than the 32 voice polyphony found on Version 1 ROM units.

This was recorded using an Alesis LineLink audio interface. Sorry about the slight clipping in places."

Roland TR-505 trigger output modification

Published on Aug 11, 2013 Harry Axten·5 videos

"I installed two trigger outputs on my TR-505 which follow the high/low cowbell voice and the rimshot/clap voice. Internally they are wired to two pins on the surface-mount gate array on the underside of the mainboard. You can get the pinout for the IC in the TR-505 service manual (page 6)."

E-mu Planet Phatt G-Funk track

Published on Aug 7, 2013 Harry Axten·4 videos

"I've been looking for a Planet Phatt for quite a long time and I finally got one for a good price. Here is a quick demo track I put together, using Cakewalk Pro Audio 9 to sequence the different parts. All sounds are coming from the Planet Phatt, with some outboard compression and reverb."

VS1103b MIDI Synthesizer v2

YouTube Uploaded by HarryMatic on Feb 1, 2012
Channel moved to Harry Axten

"A video of the new and improved VS1103b MIDI Synthesizer I have made. Schematics, stripboard layout, more photos and a full writeup can be found at : http://www.instructables.com/id/E82VEK1GXUZ7YJA/"

Doobie Rhythmini FR-112 preset rhythm drum machine

video upload by Harry Axten

Note this is the first post to feature Doobie and the Rhythmini. If you know more about either, feel free to leave a comment at the bottom of this post.

"Thought I'd record a brief demo of what this somewhat rare machine sounds like prior to selling it - not that it's anything particularly special. It's based around the Sanyo LM8972, so will have the same patterns as every other rhythm machine that uses this IC.

Not much known about the company other than it was made in Japan, presumably in the late 1970s. Possibly related to the Newport Rhythm Sound, which looks visually similar."

Korg 03R/W ROM Demos

Published on Jul 18, 2013 Harry Axten

"Possibly the cheesiest ROM demo tracks ever written, but I guess if you've come looking for ROM demos this is what you're after :-)" The Wild West of ROM demos!

TR-707 with ROM Expansion and Cymbals Board

video upload by Harry Axten

"Realised I haven't done a video showing the current version of the TR-707 ROM Expansion modification - it now allows switching kits at any time while the machine is running, done by holding down the enter button and pressing one of the first 8 step buttons. This TR-707 also has the optional cymbals board installed, which allows the last two sounds (crash & ride cymbal) to change as well. More information here - https://hkadesign.org.uk/tr707expansi..."

Roland TR-505 modified with custom LinnDrum ROM

Published on Jul 19, 2015 Harry Axten

"A quick demo of what I've spent the last week or so tinkering with. I've gotten the fairly bland Roland TR-505 from 1986 playing back custom sounds from an EEPROM. I chose to use sounds from the LinnDrum, my favourite drum machine. Full writeup can be found at http://harryaxten.altervista.org/tr50..."

HKA Design Digitizer Bitcrusher Pedal

Published on Jul 21, 2019 Harry Axten

"This is a digital sampling bitcrusher pedal I've been working on recently. It samples at 8/6/4 bit resolution and is based around an ATmega328P microcontroller.

The project is open hardware - all of the design files, code and construction details can be found on my website: https://hkadesign.org.uk/digitizer.html"

Demo with the Sequential Prophet-6.

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Korg KPR-77 MIDI Retrofit Kit

demo video upload by Harry Axten

"Updated version of my MIDI kit for the KPR-77. More info at https://hkadesign.org.uk/kpr77midi.html"

PAiA Fatman Analogue Synthesizer Demo [Keyboard Version]

Published on Oct 11, 2015 Harry Axten

"A quick demonstration of some of the sounds the PAiA Fatman synth can produce. Although I housed mine in a custom built keyboard, it's a vanilla unmodified kit. Recorded with no effects."

Korg 03R/W ROM Demos

Published on Jul 18, 2013 Harry Axten·2 videos

"Possibly the cheesiest ROM demo tracks ever written, but I guess if you've come looking for ROM demos this is what you're after :-)"

HKA Design Roland TR-626 ROM expansion

Published on Jan 1, 2019 dothkoi

"refer to the following pages
http://harryaxten.altervista.org/tr62..."

Be sure to check out HKA Design's other DIY projects. HKA Design is run by Harry Axten whose work has been featured here on MATRIXSYNTH.

"My TR-505 ROM Expansion has proven itself to be a popular kit, but I was regularly asked if it would work with the TR-505’s big brother, the Roland TR-626. The answer was no, as even though the two machines look and sound quite similar, the electronics inside are incompatible. Eventually, somebody very generously offered to send me a TR-626 to keep if I could produce an expansion kit for it. Naturally I accepted.

Sample ROM address map / encoding

The TR-626, although it has more sounds than the TR-505, fundamentally works in exactly the same way. Samples are played back at 25.0 kHz, and once again some are stored in sequential order, while others are interleaved in pairs. Cymbals are stored in 8K blocks, with a byte being read from each block in cyclical order.

The TR-626 even uses a standard JEDEC-type ROM pinout for its sound ROM; unlike the 505’s which had a horrible custom pinout, requiring a complicated adapter board. The kit I designed for the TR-626 does still use a board, but this time it’s to allow for two ROM chips to be switched. The only real catch with the TR-626 sound ROM is that address lines 6 & 8 are swapped (in the data). It’s easy enough to swap them back using an EPROM pin swapper utility.

For the new sounds, I reused all of the classic sounds from my TR-505 version, although there’s also some TR-707 sounds in there as well, thanks to the TR-626’s larger ROM size. The new sounds are spread across two banks, with LM-1 and LinnDrum sounds in one, and DMX and TR-707 sounds in the other. There's also a socket to install the TR-626's original sound ROM, so you can keep using those sounds as well.

The TR-626 has several strange quirks. One is the way polyphony is assigned across the 8 drum voices. Despite the fact that some sounds share the same key, they don’t necessarily share the same voice. For this reason, some of the key assignments for my new sounds may seem a bit odd, but the reasoning is so that you can play certain sounds together - i.e. the LM-1 hi-hats and snare drum. A full list of the sounds can be found in the manual (see below). As the TR-626 lacks an individual output for claps, I duplicated these sounds into the china cymbal and cup memory locations, so they can come out of the crash / ride cymbal outputs."

See HKA Design for additional details.