Selling more stuff

I'm selling some more redundant modules. Since I've got the Synthasystem, I don't use some of the other stuff I own, so off it goes:

All Blacet this time:
Binary Zone
Hex Zone
I/O Module
Mini Wave with Socket Rocket EPROM
Window Comparator

They have no reserve and a Buy It Now price which is less than the kit price. Have fun.

Microcon and Duophonic keyboard update

Some small progress on the Microcon front. I ordered some prototype PCBs this week. I'm sure the layout will change some as I want to make it easier to add a couple of more panel pot options. Nothing drastic, but it will change it. But, this one will be a good test to confirm the design is working.

I'm also sending the Duophonic electronics to Nyle to test. I just will not be able to make time to do it anytime soon and I want to confirm it works so I can get a production run of PCBs ordered.

Selling stuff

I find I have some redundant modules which are not seeing the use they deserve. I am selling the following. They are all Frac Rack format:

CUSTOM:
Makato filter
YU SYnth Mini Moog clone
Flight of Harmony Plague Bearer filter

NOT CUSTOM;
MOTM 1490 Moog modular filter clone

BLACET MODULES (All built from kits except one EG):
Micro LFO
Filthy Filtre
Splitter
Mixer Processor
5 - Dual Linear VCAs
6 - EGs (one was purchased pre-built)

Here are the ebay links:
Filthy Filtre
YU Synth Mini Moog filter clone
FOH Plague Bearer
Mankato Filter
MOTM 1490 Moog Modular filter clone
Blacet Micro LFO
Blacet Splitter
Blacet Mixer Processor
Blacet VCA
Blacet VCA
Blacet VCA
Blacet VCA
Blacet VCA
Blacet EG
Blacet EG
Blacet EG
Blacet EG
Blacet EG
Blacet EG

New Projects...

Hi Everyone!

I have 3 new projects to announce. First, I have prototype PCBs for the Duo-Phonic keyboard. I've got an idea how to modify a Fatar keybed to use reed switches and magnets as a buss keyboard. I'll post my results.

Second, I'm working on the Microcon. It will be a module suitable for Eurorack or standalone. In standalone, you will need to add a +/- 12 volt supply. I've got the schematic mostly captured. I'm thinking I can get PCBs in about 2 months.

Third, Tom Carpenter at Analogue Solutions is selling Red Square PCBs and panels. Pretty bare bones, but I'm putting a page together to help out those who are building it. There are some unique semiconductors and the BOM lacks some part numbers, eg: pots with switch. Anyway, I also bought an assembled Red Square and will take some photos of the inside so the PCB interconnection and other details will be more clear.

New Videos

Finally got a couple of new videos up. Triple EG and VC Trigger Generator.

Triple Envelope Generator

VC Trigger Generator

New rack enclosures

I just got my new wooden racks. I think there is something very cool when a modular is installed in a wooden cabinet. David Tatlebaum at Nice-Racks.com made some beautiful mahogany (a reasonable up-charge for the hardwood instead of pine) cases. 16U high, standard 19 inch rack width. They look great with my .COM keyboard controller.

I added a Kenton Pro-2000 MKII Midi to CV converter to allow general midi control of the modular. I also have a rack which has some non-Steiner modules (the Tuner/Monitor module is in this rack, too) which I thought would be useful; a Gabotronics X-Mega Lab which I put in a euro rack format and a YUSynth Moog Fixed Filter Bank clone (Yves did a great job with this filter). I have a 14 HP space left, but I'm not sure what I'm going to put in there. I'd like whatever goes in to have a custom front panel to match all the other ones. I'm thinking maybe a MOTM Moog filter clone, or maybe some other Moog module I can build.

Here are some photos of the system all racked and working great.

Module count:
Top left: Tuner/Monitor, X-Mega Lab O-Scope, empty, Moog FFB clone.

Row 2: Frequency Divider, Sequencer

Row 3: VCA/Mixer, Voltage Processor/Mixer, Triple EG, VC Trigger Generator, VCA/Mixer

Row 4: VCA/Mixer, Triple EG, VC Tigger Generator, Dual Voltage Follower (Slew), Power Access.

Row 5'ish: Multiple and Kenton Pro-2000 MkII

Top Right: VCA/Mixer, Variable Damped EG (This is an unreleased Steiner design I found. It's more of an ADSR type EG.), Sequencer

Row 2: Three VCOs, type "A" which have all the wave forms available.

Row 3: Phase Shifter, 3 VC Filters, Dual Voltage Follower (Slew), 2 VCOs type "B", one with square and sawtooth and one with sine and triangle.

Row 4: Trigger Converter, Ring Modulator, Noise Generator, Dual Sample & Hold, Peak Selector, Multiple, Selective Inverter, Input Amplifier, Dual Voltage Follower (Slew)

I have space for another full rack in the right side. I'm not sure I need to add anything. Someday, I might add some VCOs, or this other filter/chorus module Nyle has but never really released. I don't know...

New Video

Nyle made a video with the Synthasystem. It's up on the YouTube channel:

Nyle Playing the Synthasystem

Enjoy

Moving on...

My Synthasystem is now in the hands of Nyle. He wanted to see it and play with it, so who am I to refuse :) He wanted to play around with the VCOs, and other modules to see if everything is working right and to make some notes. I'll add whatever he gives me that's relevant to the web site. I told him he could keep it for a couple of weeks or a month. I'm hoping he'll record some music I can share. I also asked him to autograph a couple of the modules.

I still want to add a couple of modules to the system and finish the keyboard, but otherwise I think this project is done.

Si, I'm moving on to my other projects. I'm currently working on a panel mount for the Gabatronics XMegalab dual channel scope. I have this fascination with oscilloscopes and I really like what Gabriel has done. I think he's working on a scope that is easier to put in a panel, which I think is a great idea.

I'll post a few photos when it's done.

Module Building Complete!

Here are some quick photos of the finished racks (is a modular rack ever really done? :) ) Anyway, I have at least one of each of the original modules including the rare Selective Inverter. I feel like the dog who caught the car though. After 35 years, I have my Synthasystem. I guess I could play it...

5U Format Synthasystem VCF by Tony

Tony has finished a 5U format Synthasystem VCF. Nicely done Tony!

Last Details

I've been spending the last while dealing with the details. I went through all the schematics several times making sure the notes were complete and that I had included all the information from the original schematics. I double checked all the PCB component drawings to make sure I could see all the component names and values. I went through the web site and updated all the files, completed the last modules pages (like the Selective Inverter), and fine tuned the calibration procedures for the VCOs and a couple of others.

The only thing really left is the Duophonic Keyboard.

Since I have now finished at least one of all of Nyle's original modules, I started to fill out the racks. I built two more VCO Type A's this weekend. Amazingly enough, they worked first time. I'm going to do a video on calibrating these things as soon as I get my latest toy, an Agilent 200X series oscilloscope. I'm getting the 4 channel, 70MHz version. It is way overkill, but I've been wanting a four channel scope and this one has a huge display.

Agilent 2004X Four Channel 70 MHz

David

Perspective...

For perspective, here is an original, semi-custom, late model Steiner-Parker Synthasystem. Note there are some custom modules in this that Nyle didn't recognize. In the bottom row, right hand cabinet is a frequency counter. Nyle said it didn't really work that well. There are also a couple of modules which look like multiples, one with some attenuators. SDIY then, too I guess. Why not?

You'll also see that the physical size of these modules are very close to the euro-rack panels I've laid out. I really tried to keep the layouts faithful to these, but in an effort to make the widths even multiples of a euro-rack, etc. I had to compromise on some of the smaller width modules. But, I think a pretty faithful reproduction of the original...

The best compliment Nyle paid me was when he saw some of the first prototype modules racked, he thought he was looking at one of his original systems. That made me really happy.

Some progress photos

Here are some quick photos of my Synthasystem.

Completed:

• Frequency Divider
• Sequencer
• VCO A
• VCO B Square/Saw
• VC Trigger Generator
• VCF
• Tuner Monitor
• Triple EG
• VCA/Mixer
• Peak Selector
• Sample and Hold
• Trigger Converter
• 2 "Multipliers" (what Nyle called multiples)
• Ring Modulator
• Phase Shifter
• Voltage Processor/Mixer (VPM)
• Dual Voltage Follower (Slew)
• Power Access Module

Still to do:

• At least 2 more VCOs. I'm going to build one with all discrete parts to try to have a real vintage build
• Another VCO B with Sine/Triangle
• Two more VCFs
• One or two more VCAs
• One more VPM
• Noise generator
• Input Amplifier
• Selective Inverter
• One more Phase Shifter
• One or two more EGs
• One or two more Voltage Followers

Here are some photos so far:

Long time

Long time, sorry.

I'm busy building my own production modules. I have many of them completed like the Frequency Divider, One VCO Type A with high frequency tracking compensation (two more at least to follow), Phase Shifter, Ring Modulator, etc.

I also broke down and bought a Tinisizer, http://www.anyware-instruments.de/. This is truly a unique and cool synthesizer. "Analogue Tommy" outdid himself with this one. I have serial number 14, so I think it is fair to say it is a "boutique" synthesizer. I'll publish a more complete review with thoughts after I've had more time to play with it. So far, however, I love it.

More small updates to the web site, so if you purchased a PCB from me, please check to see if your module is affected. Nothing big, just clarifying some construction notes, BOMs, and a couple of component value changes.

Thanks for reading.

Progress

There's not too much to say right now. I'm working on building the "production" modules for my own system. I have all the panels, PCBs, etc. now and I'm just building. I'm thinking in the next month or so I'll have it all assembled.

In the interim, I'm building cables, multiples, replacing the keybed in my Moog Voyager, trying to make time to play around with my just received Zeroscillator, and learning software. In other words, having a lot of fun.

I will re-visit the Steiner Duophonic keyboard after I've got more of the final modules built and working. I have the major pieces to do the interface between the matrixed keybed and the Steiner circuit, I just need to decide the form factor for the PCB and other electronics.

VCO High Frequency Tracking modification

Hi everyone.

Well, I thought I was done, but when I finally got to playing with the few modules I actually have racked, I found out first hand that the original Steiner VCO was not immune to the dreaded high frequency tracking problem in exponential converters. I approached Nyle to see if he had any ideas and he had actually explored this problem, and had added a correction circuit to the Microcon. He drew a couple of ways to add the correction and I undertook to investigate. I ended up using the one which was the most direct to implement and did not require cutting PCB tracks. I also have built a very small PCB which can be added as a modification to the VCO if the HF tracking error bothers you.

I'm not going to re-issue the VCO PCB with this correction modification on the PCB. The original did not have it, so mine won't either. This is an easy modification and only requires you to solder three wires to the main VCO PCB. The best thing is it works. I get excellent tracking from 50 to 3200 Hz.

I should also note, using a Polystyrene capacitor for the VCO timing capacitor, and good metal film resistors with a low temperature coefficient makes this a very stable VCO. I left mine on in an open rack for a couple of days and had a drift of under 1 %.

I also updated the calibration section of the VCO page, in particular the Sine shaping section. I'm planning a video for the YOuTube channel going through the calibration procedure, so stay tuned.

Anyway, see the web site on the VCO and in particular the HF tracking page.

http://www.xmission.com/~dingebre/VCO_A_1.4.html
http://www.xmission.com/~dingebre/HF_CORR.html

If you bought a VCO PCB from me and I haven't written you, please PM or email me. I'll send you a PCB when I get them. Probably two weeks.

David

DONE! FINI! FIN! IT'S ALIVE!

I pronounce the Synthasystem fully resurrected. The last module was the Ring Modulator. Nyle spent a couple of hours with me today and it works. I can now make the order for a small production run of the last three PCBs. The panels are done and now I'm going to build my modules.

I'll update the web pages over the next few days and get the module information up to date.

Technically, I suppose I have to do a keyboard, but for all practical purposes, the Synthasystem modules are all done and tested.

Keep watching for more videos, build photos, etc.

David

First Videos are up

The first YouTube videos are up. Have a look and watch for more!

http://www.youtube.com/watch?v=U0uZzLIi0jk

http://www.youtube.com/watch?v=QimHwslIuoE

http://www.youtube.com/watch?v=G3FSFm6JH-Q

MC1495 blues

Nyle got the Ring Modulator prototype and right now, it looks like the 1495 is bad. I tried a second one which did the same thing. Tonight, I'll take some of the other ones and will test them to see if I just have a whole batch of bad chips. Good news is the ON Semi pieces are on their way from ArchadeGameChips.com and I'm hopeful they will work.

One bug, AAARRRRRRRRRGGGGGGGG

The Input Amp works, the Voltage Follower works, the VCO Bb (saw/square) works... the ring modulator doesn't. I'm confident the capture and layout are faithful to Nyle's design, but I was sure on the ENVDT, too and I had missed a diode completely and had one net wrong. Nyle took the PCB from me today and is going to play with it.

Honestly, I just think I have some bad MC1495s. They are the older Motorola parts, but are from a reputable dealer. That said, ArcadeGameChips has a big stash of the ON Semi ones. I ordered a bunch and if Nyle can't find something I did, I'll try the ON Semi chips.

On the bright side, the only module I haven't built is is the VCO Ba (sine/triangle). Because it was derived from the VCO A, and had no new circuitry, I'm very confident it will work. I'll build one this weekend just to make sure.

I'm going to hold off just a bit on the Duo-Phonic keyboard and I want to get all my modules built and racked. I need to build a couple more oscillators, filters, VCAs and then I'm calling the modular part good.

I'm still conflicted on what format exactly to use for the keyboard electronics. I could do a typical keyboard, or build it in its own standalone box with midi inputs, or even as a racked module. I want to put a Pitch Bend wheel in in place of the panel pot Nyle used, but that might be awkward on a vertical panel. Anyway, that's why I want to wait. The way it will work, I think I will build it either as a separate box or racked module. But, that's for later.

YouTube channel

I've setup a YouTube channel for videos. Nothing yet, but check back for news.

http://www.youtube.com/user/dingebre

Life is good

So, I received the last three prototype PCBs; Voltage Follower, Ring Modulator, and Input Amp. When these have been checked out, I'll order a small production run and will call the modular part of this done!

I'm working with the Duo Phonic keyboard right now. I captured the schematic and have decided to use PCB mounted switches and pots where possible. Like the sequencer, it locks in the panel layout, but I think it will make other aspects easier in the long run.

Nyle has been playing around with the Photo MOS switches I want to use to emulate the buss keybed. He thinks they will work well. That is good news as it will make the interface between the Doepfer MTC64 and the Duo Phonic keyboard electronics easier.

Stay tuned. I'm still playing around with video/audio and will post soon.

Getting really close!

The project is getting very close to fruition. I've recently tested and now have working the VC Trigger Generator, Noise, Selective Inverter, Phase Shifter, Voltage Processing Module, and tonight, the Tuner Monitor. The Voltage Follower (slew or portamento), Ring Modulator, and Input Amplifier prototypes have shipped and should be here early next week. After that, I need to finish up some panels and then order some production PCBs.

Nyle came over last night and spent a few hours helping me go through the Selective Inverter. It is a very interesting module, and I don't quite know how to explain it. I guess because I'm still trying to understand it. It was a specialty module Nyle built for a customer and very few were every built.

Now, onto the keyboard. I'm starting with the duophonic keyboard. I've captured the schematic and will start the layout this weekend. I think I've got a way to easily use any new matrixed keybed or even a generic midi controller as an old single buss keybed.

First, Doepfer makes a DIY unit they call the MKE. It takes a Fatar matrix keybed and outputs the midi information like note on/off, velocity, etc.

Second, Doepfer also make a unit they call the MTC64. It converts midi note on/off to a TTL voltage for 64 notes. You can cascade two to get all 128 notes if  you want.

Working backward, I can use the MTC64 and feed each TTL "switch" to a solid state relay or even a reed switch relay. That relay becomes the switch for the buss. I can then build the resistor ladder down this series of relays and I got a single buss, 61 note keybed that is just waiting for midi note on/off messages. the cool thing about this system is it is now a general purpose midi to Steiner Duo-Phonic CV generator. You can plug anything which generates midi note on/off signals. Nyle saw he could plug his EVI midi out into such a controller to play his modular when he gets it built.

The next step will be to take a Fatar 61 note keybed and using the MKE, build a cool looking keyboard. In reality, I can just use my Synthesizers.com keyboard.

I'm thinking I'll build the keyboard electronics with relays and MTC64 into its own box. It will have wheels, thanks to Synthwood, for portamento and pitch bend as well as the other knobs for tuning and scale. There will be a companion panel for the modular which will connect this "module" and make the various outputs available. I'm really liking this little find I made on the Doepfer web site.

OK for now. I should have a bit of a breather from work next week. I still really want to put together some video of the modules. Nyle is offering to help make them which I think is great!

The web site has had a bunch of updates in the last month or so. Have a look.