New remix of Adam Buxton’s Ramble Chat jingle. The only rules were that you had to use at least two of the original audio files and it had to be 1 minute or less long. Was quite surprised at how much multi-tracking was going on with the vocals so I thought it was only fair to use most of them.
Well, it was a bit of a battle, but I finally have a working display for the Kurzweil!
The removal and replacement of the LCD itself wasn’t too difficult, but the backlight didn’t appear to be working on the new LCD. So I checked the two connection pins on the circuitboard, but couldn’t detect any power coming out of them.
I then checked the specs for the LCD and which revealed it accepts a maximum of 13V, so I hooked up a 9v battery to it and the backlight burst into life.
I guess there’s a component somewhere in the circuit which has failed or a dry solder point perhaps, but a quick visual inspection didn’t reveal anything obvious, so I decided to look for an alternative 9v source.
Fortunately, the 900 MX has an external 9v wall wart PSU, so I ran wires from the input socket and power switch to the backlight. The reason for running it after the power switch of course is because otherwise the backlight would be permanently on!
After reassembly, I did some testing and found that there was good and bad news.
The good news
I could navigate through the menus fine, select patches and change MIDI settings. All buttons work too.
The MIDI indicator responds to incoming data from my controller. In fact, the MX has a handy built in MIDI monitor function so I could see the note on / off information as well as pitch bend.
The bad news
It doesn’t make any sound. Pretty bad news I think you’ll agree.
So I whipped the top off again to have a good stare at the circuit board. I noticed two IC’s with Left and Right screen-printed below them on the circuit board, so guessed that might be a good place to start. The IC’s were marked PCM56P, which I think are Digital to Analog converters (DAC’s).
However, the likelihood of both DAC’s failing at the same time seemed unlikely, so I carried on looking for any shared components in the same general area. That’s when I chanced upon a relay by American Relays Inc, marked AD2A05D. I must profess, I didn’t really know what it did, but it was positioned on the circuit board between the DAC’s and the output phono jacks so I guessed the sound must be somehow routed through it.
I then chanced upon a webpage dedicated to problem solving for the Kurzweil K1000 http://k1000.net/problems.htm which revealed I could be onto something. Under the heading ‘No Sound or Distorted Sound’ it read..
“This is most often caused by a faulty audio output relay – a relay that connects the audio to the two output jacks on the back of the expander or keyboard. If the relay gets stuck or fails, no sound will be heard at the output jacks.”
So I’m hoping that’s also what’s wrong with my MX. Being in the UK, the chances of finding the original relay are nil, but I managed to find what I think is a compatible one on ebay. It’s the Hamlin HE722A0510 which is a 5v DPST reed relay with diode.
To be continued…
Happy New Year! Reflecting on the strange year that was 2020, the additional time spent at home was actually very productive for me. Certainly, I’m intending to keep the momentum going so thought I’d have a trawl through my archives to see if there were any hidden gems to share for my first post of 2021.
Here’s a previously unreleased remix of the seminal Acid House classic, ‘Acid Man’ by Jolly Roger, which I created back in 2003.
It starts with a slight Detroit influenced intro before going full-on tribal acid. All I know is that it had me bouncing in my chair this morning, which can’t be bad for something tucked away on a hard drive for 17 years!
No socks for me this year. My in-laws bought me a red Behringer TD-3!
Have repurposed my old guitar FX pedalboard as a stand with built in Delay and Reverb. The Micromix allows me to blend the dry and wet signals as well as creating feedback loops via the second output of the reverb.
Picked up what I hope will be a bit of a bargain on eBay, the Kurzweil 900 MX MicroExpander.
There’s not a lot of information out there, but I believe it was launched in 1989 as part of their Home Product range and features 63 sounds taken from their flagship K250 including pianos, bass and strings. Being a home product, there are some compromises such as using phono plugs rather than 6.5mm jacks and having a wall wart power supply rather than a built in PSU, but it does retain the 12 note polyphony of its older sibling.
This particular unit looked a little worse for wear on eBay, with some scratches on the top and no power supply. It didn’t look too bad when it arrived today though, but I had no idea if it would actually work.
Connecting a spare 9V AC PSU, the MIDI light flashed on for a second, but it appeared the backlight on the LCD was dead. I could just about read the text though and navigate through the sounds – so far so good.
The 900 MX uses a 16 character, single-line LCD so I set about sourcing a replacement, finally settling on a Winstar WH1601 which you can find on eBay. Unlike my Akai S2000, the LCD isn’t wired directly to the circuit board, so this should make it much easier to swap out. I’ll follow up with more details once I get the LCD replaced, but for now, check out this video from Espen Kraft where he demos the similar 1000 PX
Still waiting for the replacement LCD, but it has at least shipped now so should arrive next week. Meanwhile, I’ve started reviewing the pinouts on the old LCD as it’s in 2 rows of 7 pins (plus separate pins for the backlight) rather than a single row of 16 as is on the replacement.
This website has been quite illuminating (pardon the pun) and revealed that the pins are numbered in pairs.
Have started work on upgrading my Akai S2000, so thought I’d capture some notes for posterity on how to get the Gotek floppy emulator working.
Swapping the Floppy Drive for the Gotek emulator
Removing the old floppy drive is just a case of removing 4 screws from the underside of the S2000 as well as the power and IDE cables. This gives you access to a further 4 screws which secure the floppy drive to the metal chassis.
Once separated, you can then mount the Gotek onto the metal chassis, connect the power and IDE cables to it and finally reattach the chassis to the S2000 itself via the 4 screws on the underside. All being well, it should then look something like this…
Gotek / Flash Floppy Configuration
The Gotek I ordered already had FlashFloppy pre-installed, so I went to their Github page to see what configuration settings were needed.
Using a USB drive formatted as FAT32, I created a file in the root directory called ‘FF.CFG’
I then updated it with the relevant parameters for Akai samplers which in my case were…
host = akai
interface = ibmpc-hdout
nav-mode = native
The instructions also mention setting jumper S0 which a quick Google revealed means ‘Disk 0’. Mine arrived set as S1, so I just moved the jumper to S0.
S2000 OS Image
The other thing you will need is a copy of the S2000 Operating system (preferably v2.0) in HFE format. I got my copy from http://akai.mnx2010.nl/ then copied it into the root directory of the USB drive.
And that should be all you need to get the S2000 to boot from USB via Gotek!
Here are some links that helped me along the way…
Couldn’t sleep last night. Kept having ideas on how to improve the sequencer, so in the hope of having a better nights sleep tonight, I announce version 1.1!
First addition is variable pattern length for each of the 4 sequencers, so you can create polyrhythmic patterns.
Next, I’ve added a toggle to switch between the original note-in trigger mode and a new host mode, synced to Ableton’s tempo. This allows for sustained notes to be played with the parameters being changed over time, rather than per note.
Then there’s a clock divider so you can choose what speed the host mode runs at.
And finally, I’ve changed the purple colour of the fourth sequencer to pink, because, why not 🙂
Hope you like the changes, I’m really quite pleased with them! Here’s a quick (and noisy) demo…
Only had one more idea, namely a slew level to sweep between the parameter changes rather than jump to them, but not even sure if that’s even possible yet. I’ll leave that for another time though.
Very pleased to announce another new maxforlive device, this time a 4 channel, 8 step MIDI CC Sequencer! Whilst it was primarily designed for my Korg NTS-1, I’ve made it configurable so you can choose any 4 MIDI CC’s you want to sequence by typing their numbers in the boxes at the top. By default, it’s mapped to the Korg Oscillator Type, Shape and Alt controls.
You might be wondering why it only has 4 knobs if there are 8 steps. Well, the design was inspired by one of my favourite Eurorack modules, the DinSync ModSeq where each knob controls two steps. So, taking the first green knob for example, on step 1 it would output a value of 25, but on step 5 it would output the inverse (102). The second green knob would output a value of 80 on step 2, then on step 6, it would output the inverse (47) and so on. After it reaches step 8, it loops back to 1 again.
It’s available to download on maxforlive now, and I’ll hopefully upload a demo video in the next couple of days!
Getting some great feedback on my NTS-1 editor, but someone asked if it could be a little less random. That got me thinking…
Watch this space!
Well, the Korg NTS-1 editor is finished! Had to deal with a weird quirk where the randomiser was being triggered by both the note on and note off messages, but I managed to get around that by using the stripnote function which I’ve learnt is perfect for that sort of thing.
It’s available to download from maxforlive.com now.
** UPDATE 4th December **
I even got a retweet from Korg USA 🙂