Category Archives: Synth

PPG wave 2 – loading programs from CASSETTE

I just put a video up on YouTube, showing how to load programs using the CASSETTE port at the back of the PPG wave 2.

This PPG wave 2 probably has a weak battery and loses its programs after a few months if it’s not turned on. The battery will eventually be replaced with a modern, non-rechargeable lithium battery and a diode.
Instead of using a cassette tape, I’m playing the data from my MacBook. The MacBook is set at 100% volume, the PPG seems to be very sensitive about the levels. The program audio that you hear in this video from 0:50 should theoretically work to restore the programs in you PPG. That’s why I chose to keep it at the right level, -5 dB, in this clip.

Racking a PPG Wave 2.2 – part 2 – display change

Display change

Yesterday I got my new display and digital board back from Alexander at Virtual Music in Vienna. The old display had to be changed to a newer one for two reasons, even though the old one still worked.

First of all, the old one would never fit a 19″ rack since it’s too wide. The new one is 182 mm, so it will fit.

Secondly the old one was very hard to read, especially if you were not straight in front of it. Since the PPG Wave 2.2 is supposed to sit in a rack, sideways visibility is crucial.

As you can see on the pictures it’s not just a matter of swapping the old display for a new one – serious modifications must be made to the so called digital board. The digital board contains the driver for the display and the two keypads. All work was very professionally done by Alexander! I plugged it in and it worked instantly!

The encoder for the contrast was also replaced since the old one was kind of intermittent.

V8.3 firmware

Virtual Music also happens to be the reseller of the newer V8.3 firmware that adds a lot of sysex and fixes bugs. V8.3 was ordered as well as new battery kit. I tried to change the eproms, but the old ones were really stuck and impossible to remove without using brutal force, which I didn’t want to. I will have to install V8.3 when the board is removed from the chassis.

The next step is to order a new 6U 19″ rack chassis.

 

Racking a PPG Wave 2.2 – part 1 – intro

Intro

I recently got this “racked” PPG Wave 2.2. The history of it is quite unknown, but this brutal treatment was done in Germany by someone else than me. I’m innocent!

Someone has cut this Wave in half, removed the keyboard and put the right side  on top of the left side using standard screws and standoffs from a hardware store. It’s a shame since it looks as though the panel was in great condition – most Waves suffer from the graphics peeling of, especially in the area near the logo close to the push buttons.

Software wise it’s running OS V6 and has MIDI. MIDI is the way to control it since it has no keyboard. Since it’s a PPG Wave 2.2, it’s compatible with the Waveterm A – which I don’t have. There’s however an upgraded OS, V8.3, which makes the PPG Wave 2.2 compatible with Waveterm C, a software version of the Waveterm A and B.

Unfortunately, the serial is unknown as on most PPG Waves. It was hand written on a label on the back with a permanent pen that wasn’t as permanent as it was supposed to. It is probably an early/mid PPG Wave 2.2 as it has the same display as the Wave 2 but is equipped with factory midi.

I asked myself – what have I done – buying an expensive piece of junk like this that could electrocute me. And the racking procedure won’t be cheap and will take a lot of man hours. However, I’m running out of space in the studio and PPG Wave 2.2s don’t grow on trees, especially if they’re not upgraded with 2.3 voice cards. So I decided to take on this challenge and make myself a one of a kind rare PPG Wave 2.2 rack. I guess my metal skills from working with cars will be needed…

The width problem

The problem with the current “racking” is that it won’t fit in a standard 19″ rack – it’s simply too wide! A standard 19″ rack case has a panel width of 19″ (483 mm) , but the case width is often closer to about  17.5″. I’ve found a rack case supplier that has a model with an external width of 435 mm and inside width of 432 mm. This means that 432 mm is what I have to deal with.

The mainboard with all voice cards that is on the lower section is luckily enough around 430 mm. There’s also possibility to shave off a couple of mms at the far ends. The pots are placed on a board that is around 400 mm. The “Basis” and “Master Volume” pots to the far left are not on the board and can be placed anywhere.

The upper section has the power supply and MIDI and audio outputs at the back. They can easily fit within in the width. The biggest problem is the so called digital board that has the keypads and the LCD display. Together they have a total width of 460 mm so they can impossibly fit. One solution is to cut boards so one end is in a 90 degree angle (like this racked 2.3). I have  chosen a different path – changing the display to a more modern and narrower one that also has backlight.

The original display must have cost a fortune back then, and it’s not directly compatible with modern displays. Therefore the digital board and display will be sent to Virtual Music in Austria to be modified.

I won’t reuse the original panel metal since a few things will have to be modified and moved around. Instead I will create new original looking graphics for the faceplate so it looks factory.

The plan summarized

  1. Make a plan
  2. Change the display to a narrower modern one with backlight
  3. Upgrade the OS to V8.3
  4. Put everything in a rack case
  5. Create new graphics

Replacing the backlight of a Roland MKS-80 rev 5

Today I changed the backlight on a Roland MKS-80 rev 5. If the backlight is very weak, the electro-luminescent foil it’s probably worn out. They simply have a limited lifetime. When this happens you have three choices;

  1. Ignore the problem and use a flashlight
  2. Replace the whole LCD
  3. Replace the foil

I think the missing backlight is really annoying and makes the synth harder to use, so not doing anything was not an option.

Replacing the LCD would probably not be too hard, it has standard dimensions of 80×36 mm and are cheap. If you’re lucky a new LCD would just work, but in the worst case there could be compatibility problems. I’m not saying there will be problems since I haven’t tried it, but there’s an obvious risk. For example, changing the LCD on an EII to modern LCD also required changing a chip, otherwise the LCD just displayed strange characters.

I went for the third option, namely just replacing the foil. There are some companies providing replacement foils cut to the right size in various colors. However, I thought I’d give Roland a try since they seem to have a lot of old stuff left in stock. So I emailed Roland Scandinavia asking for a foil for a Roland MKS-80 rev 5. Since they didn’t know exactly what part was, they emailed me the service manual for me to look up the part number.

After browsing the manual I finally found what I suspected was the correct part, namely “15029181 EL-101 (electro luminescence)”. Roland said it’d be around €20 and recommended me to visit my local Roland retailer to order it, so I did…

Replacing the foil is quite straight ahead. Most of the work is getting to the LCD. To do this you of course have to remove the lid, and then the front panel. Then you have to undo three screws and three standoffs so you can fold the two voice boards upwards to finally reach the CPU-board at the bottom which the LCD is connected to in three places. Two of the connectors are snapped in place, so use a small, flat screwdriver to fold the latches away. Then you finally remove the four screws holding the LCD in place, remove the LCD and heat up your soldering iron.

I used desoldering wick to remove the old solder. Then it’s just a matter of sliding the old foil out of the LCD. The “new” one I got from Roland is probably NOS, because it looked exactly the same as the original one. I slid it into the LCD and soldered it’s two legs to the circuit board. I actually cut away about two mm of each leg since they were a bit too long. I powered the MKS-80 up, and the backlight was really bright – success! However, it seems that I should have placed it a little more to the right.

Then it was just a matter of reassembling the MKS-80. However, this was not as easy as disassembling it. The tricky part is the front panel that has three rectangular holes for the OMNI, POLY, MONO leds. The leds have to go straight in their holes, otherwise the front panel won’t sit where it should. There’s also a similar led for MIDI MESSAGE to the right which makes it even more trickier… Do not try to force the front panel, just take it easy and align the leds, and do try not to get too annoyed.

I put the MKS-80 back in the rack and fired up my DAW to realise that the MKS-80 sounds great and the backlight is strong – but – the MIDI MESSAGE led doesn’t work… I will replace it some other time.

Roland JX-3P sold

The JX-3P was sold today to finance the Prophet 5. I really liked it, it had character. For a while it has been the only affordable vintage sounding Roland poly, but I’m certain the prices will rise! It’s so much better than the later JXs and Alpha Junos.

SCI Prophet 5 bought! (and reloaded with patches!)

Today I bought an SCI Prophet 5 rev 3.0! This is cheapest one of the three editions made. That doesn’t mean it came cheap, I’ll have to sell at least 3-4 synthesizers to make up for the loss.

Rev 3.x is the last and most common main revision. 3.3 is the last sub revision and came with support for SCI’s midi kit, but it also got 120 patch memory slots. The 3.2 can easily be upgraded to 3.3, but 3.0 and 3.1 can’t without lot’s of hardware modification. Not having the capability to be upgraded to 120 memory slots or getting the official midi make 3.0 and 3.1 the cheapest ones. Kenton does however offer a midi kit, but it’s a bit expensive, so I think I’ll pass. The P5 has CV/gate for one voice if you need to sequence.

The seller said the P5 had the original patches loaded, but clearly it didn’t. On non-midi P5s patches can be saved to and loaded from cassette. Of course any audio recorder better than a tape recorder will do.  The patch data can be downloaded from analog.no as 8-bit wavs.

I downloaded bank 1 as it contains the first 40 factory patches. To be able to import it in Logic I had to convert it to 24-bit audio. I followed the instructions below taken from Prophet 5 Resources

  1. Look at the Prophet’s rear panel and set the Data Record slide switch to ENABLED.
  2. Set the tape to the position that holds your program. Listen for the announcement.
  3. Set playback level play at 0db.
  4. Hold the Prophet’s orange RECORD switch down while pressing the grey LOAD FROM TAPE switch.
  5. The Prophet front panel will go dark, except for the LOAD FROM TAPE switch indicator will be lit.
  6. The L.E.D. will go out after about 40 seconds, now Stop the tape.
  7. If the LOAD FROM TAPE light blinks, an something has gone wrong. Adjust your playback level and try again.

Unfortunately, this didn’t work. And the instruction doesn’t mention how to try again, or describes the confirmation you get if the loading was successful.

I read somewhere that some poly Oberheim from the same era needed quite a hot signal for it to work, and therefore the headphone jack was recommended instead of the ordinary outputs. Before testing the headphone jack I tried all output settings on my RME Fireface: -10 dBv, +4 dBu and Hi Gain – but it didn’t make any difference. Except on Hi Gain where I once actually got the blinking led, which means error. Maybe the signal was hot enough at least at some point?

I connected the cable to the headphone jack instead and restarted the load procedure. In the first run I had the headphone volume encoder on very low volume, and it actually gave an error – some success! I tried again by pressing the “Load from tape” button. This time I set the headphone volume encoder to point to a quarter to, and believe it or not, the patch data was loaded and it was confirmed by the P5 rebooting.

I shot a quick video of it, first showing a failure, then success:

Here are my additions to the standard instructions:

  • The LOAD FROM TAPE light will stay on until it gets something loud enough
  • The P5 will reboot after a successful load (you’ll notice the TUNE button light up for a couple of seconds)
  • I don’t know how to cancel a load, but if someone knows, please tell me
  • The P5 wants a hot signal. Start low and gradually increase the output level

Waldorf Microwave rev A bought

Today I found a Microwave rev A locally on Vend. As always, I discovered the ad a couple of hours too late, it was already “sold”. After almost two days the ad was still there and I contacted the seller who said the buyer had backed out because he’d bought a guitar instead. Sounds a bit strange going from a Microwave to a guitar, they’re on totally opposite sides of the spectrum…

I convinced the seller I could get there quick and pay more than the price he’d put in the ad. So I went there and bought it. Apart from a small scratch on the front and a couple of scratches on top (not noticeable when it’s racked), the cosmetic condition was very good. The “alpha” wheel was a bit loose though.

The rev A is cosmetically different with a green bottom LCD display and blue anodized aluminium. The rev B is painted with a paint that peels of and has a black bottom LCD display. The biggest difference though is that they use different filters, the rev A has CEM3389s and rev B has CEM3387s. The rev A is valued higher than the B.
Read more about the differences here!

Sometime in the future when I’ve time I’ll be doing a A/B test, literally speaking.

Roland Juno-60 midi kit

Last night I upgraded my Juno-60 with the MDCB60 midi kit from D-tronics. Even though I prefer not to use midi, there are situations where midi is nice to have, for example when doing quick sketches that you want to save, or try different sounds without manually having to play the same sequence over and over.

The DCB port

The Juno-60 was an upgraded version of the Juno-6, with the main difference that it had memory section, just like it’s main competitor Polysix. Another addition was the DCB port, which was Rolands predecessor to midi. Remember, this was back in 1982 and midi was first introduced in 1983. Before midi, Roland had DCB, Oberheim had it’s own proprietary protocol etc. Too my knowledge, only the Juno-60 and some of the Jupiter 8s had DCB . The JX-3P was the first Roland synth with midi, so DCB didn’t live more than a year or two. We should be thankful that the manufacturers actually managed to agree on the midi standard, that still lives 32 years later, even though it has its flaws.

Luckily, DCB is quite primitive and therefore simple to convert to midi. The MDCB60 only adds note on/note off, so there’s no pitch bend, program change, arpeggiator sync etc.

Installation

The installation was very straight forward:

  1. Open the Juno
  2. Remove the DCB-connector from the back
  3. Cut one zip tie so the DCB-connector reaches outside the synth
  4. Unsolder all wires
  5. Insulate the green and purple wires
  6. Solder the wires to the MDCB60
  7. Screw it to the back of the Juno-60
  8. Add a new zip tie
  9. Solder the wire from the MDCB60 to the gate pin on the Juno-60 board for 5V power

There’s a video here describing the installation, however, they seem to take the 5V power from another place than the gate pin.

The installation took less than an hour in total, and it worked straight away! I recommend this kit if you need basic midi on your Juno-60.

Roland Juno-60 & TR-626

Today I did a great package deal, bought a Roland Juno-60 & TR-626.

My Roland Juno-6 is one of my absolute favorite synths, and nothing I’d ever sell – but it has one “problem” – no patch memory. To be honest that isn’t exactly a show stopper –  it’s a simple synth, and writing down the settings on paper isn’t that hard. However, when a Juno-60 in about the same condition appears locally for the same price I paid for the Juno-6, “upgrading” to the Juno-60 was a no-brainer.

By incident, the guy was parting with all his stuff and also offered me a TR-626 as a part of the deal. To be honest, I don’t know what to do with it since I’ve got the heavy digital machines like the LinnDrum and Oberheim DMX, but it has actually grown on me. It actually sounds quite gritty and louder than the beige box suggests…

Syncing LinnDrum, Polysix, JX-3P and Juno-6 with Logic (or other sequencer) using ReCycle files for external clock

Download RexSync files

The longest title of a post so far, but it describes exactly what this post is about. Syncing those vintage instruments with a modern sequencer without any additional hardware. The only thing needed is a sound card with more than two outputs.

How the vintage stuff works

In this tutorial I’ll be using three different instruments. They all have different kind of functions that deal with time. The LinnDrum is a drum machine and therefore has a built in sequencer which you can set at a certain BPM. The Roland Juno-6 has an arpeggiator with a simple slider – you never know the exact BPM it plays back on. The Roland JX-3P has a very basic 16 step sequencer which also has a simple slider and therefore unknown BPM.

For the instruments to know when to hit the next note or drum sound they have a built in clock. The clock generates pulses, and a pulse is simply 5V for a couple of milliseconds.

All the instruments each have one input jack at the back allowing us to feed them with our own pulses instead of the ones from the built in clock.

The Rolands are the most simple ones. Each time you feed the Juno-6 with a pulse in the “arpeggio clock in” input, it plays the next note in the arpeggiator.  The JX-3P works in a similar way, feed the “seq trigger in”  with a pulse and it plays the next note in the programmed sequence. This means that if you want your sequence or arpeggio to run play 16th notes, you just feed it 16 pulses each measure.

The LinnDrum works in a similar way, but it expects 192 pulses each measure to its “sync in” input jack. This might sound like a lot – and it is. If you listen to the sync signal sent to the LinnDrum it’ll sound like a very loud, annoying buzzing sound, whereas you in a 16th pulse signal would hear each pulse as a “tick”.

In addition to the sync in jack, the LinnDrum also a sync out jack. Back in the day, when recording a song with a synced LinnDrum, you’d do like this:

  1. Connect the sync out from the LinnDrum to your mixing desk, preferably to the last track, eg 24. The reason for putting it at 24 is that the signal is very strong, and could “leak” to the neighboring track (23). Track 23 might have to be unused of this reason.
  2. Run the LinnDrum for a little longer than the song duration and record the sync signal to that track.
  3. Connect the output of channel 24 to the sync in on the LinnDrum which would make LinnDrum sync to the recorded track.

To sum it up: External syncing of these old instruments work in a very simple way – you override the pulses from the built in clock with  your own external pulses.

How my convenient solution to this works

So, from where do you get the pulses? There are hardware solutions like the Doepfer MSY-2 available, and software solutions like AU/VST sync generator plugin.

My solution is very simple and convenient. I’ve sampled a clock pulse from my LinnDrum and created a couple of Recycle files that each are one measure long. These Recycle files has pulses from 1/4 note up to 1/192 note. As you probably know, Recycle files are like Apple Loops, they automatically adjust to the tempo of the sequencer by using a “slicing” method.

How to use (in Logic)

  1. Create a new mono audio track.
  2. Set no input and choose the output to eg output 3 of your sound card.
  3. In your sound cards mixer application, make sure that output 3 isn’t patched to your stereo output. You don’t want to listen to the sync signal, it’s quite annoying.
  4. From the output 3 jack of your sound card, connect a cable to the sync in on your instrument.
  5. Drag and drop one of the Recycle files to the track. You’ll get an error message, here it’s important that you choose Don’t fix, otherwise Logic’s “fix” will make it go out of sync.
  6. Press play in Logic and hopefully the instrument will start to sync!

Roland Juno-6 instructions

  1. Insert the cable with the sync signal in “Arpeggio clock in”
  2. Turn on the arpeggiator
  3. Try to play on the Juno-6 (nothing should happen)
  4. Run your sequencer
  5. Try playing again, arpeggiator should now sync to the sync signal

Korg Polysix  instructions

  1. Insert the cable with the sync signal in “Arpeggio trig in”
  2. Turn on the arpeggiator
  3. Try to play on the Polysix (nothing should happen)
  4. Run your sequencer
  5. Try playing again, arpeggiator should now sync to the sync signal

Troubleshooting

Q: Nothing happens!
A: Make sure that the sound card’s output really outputs the sync signal.

Q: I can’t stand the noise!
A: You have to configure your sound card not to include the audio output that’s used for the sync signal in the master stereo mix. On my sound card, the RME Fireface 800, this is done in the Fireface Matrix.

Q: Sync is not synced!
A: The output level of the sync signal is important. A level that’s too low can make the instrument miss certain pulses.