A blog relating to vintage analog Roland "x0x" musical instruments. Primarily focusing on the SH-101, MC-202, TB-303, TR-606, TR-808, TR-909. Also featuring eurorack modular synthesis and DIy projects.
I used the kit to make a simple polarizing CV mixer. To make this all you need is the Synovatron kit, seven 100k resistors, a dual opamp (tl072/tl082/lm358 etc) and an spst switch.
The inputs are unbuffered but you could simply add a couple more opamps to buffer them if you wish.
click the picture to download a PDF of the schematic.
Hope you are all having a nice holiday. Here's a quick overview of the DIY kit#1 I just received for evaluation from Tony at Synovatron.
All in all its a great little tool for those of you that like to DIY your modulars, I'll be doing a follow up video at some point so keep your eyes on the blog to see what I make with this kit.
Here's the details of what you get with the kit,
Eurorack Modular Synth Prototyping Kit 1
This is one of the new Eurorack standard modular synth prototyping kits for synth constructors and enthusiasts; these kits will enable you to make neat prototype or one-off projects that accomodate bracketed pots, PCB mounted jacks, switches and LEDS so that they can be easily mounted to a module front panel. The idea is that you build your designs on the prototyping boards supplied and get the front panel manufactured separately, either by yourself, or by a company such as Schaeffer (A Schaeffer template file can be provided that you can use directly or can modify as you require). The PCB header and ribbon cable assembly is compatible with Doepfer power bus connectors and supports CV, Gate and +5V connections too.
This kit comprises the following components:-
* 1 x DIY1 prototyping circuit board (104.3mm x 47mm x 1.6mm) with dedicated pot, bracket, header and capacitor locations, power rail bussing and a 0.1" matrix breadboarding area * 5 x control pots (50k linear supplied as standard but 10k linear, 100k linear, 1M logarithmic or a mixture are available upon request - ask about availability) * 5 x pot mounting brackets * 2 x 100nF decoupling capacitors * 2 x 16-pin headers
* 1 x DIY2 prototyping circuit board (100mm x 20.3mm x 1.6mm) with dedicated jack socket and/or toggle switch locations and a 0.1" matrix breadboarding area * 5 x 3.5mm jack sockets
* 1 x DIY1 to DIY2 linking ribbon cable assembly (16-pin IDC socket to 16-pin IDC transition, 75mm long) * 1 x standard ribbon cable assembly (200mm long)
Came across this rather nice page by tinyloops that might be of interest to some of you, its a reference to programming the TB-303, here's a quick quote from the site.
"This "quick button reference" is meant to be exhaustive. This reference only makes sense reading after you have read the manual, especially pages 49-63 which explain about the beauty of mixing different step modes into one track. This reference does not cover that. I'm trying to give some insight on what buttons to press to achieve something in the process of programming the sequencer. The approach is an effort to bring some logic in the combination of workflow and button arrangement."
Cast your mind back seven months and you may remember this post about some x0xb0x front panels by Substyler based on my "TB-x0x" custom x0xb0x.
Well now Substyler from x0xsh0p has made them into case kits which you can now purchase. The client for this job that arrived on my workbench bought one of these kits and asked that I fit it for him.
And so here we are with a couple of pictures of the unit before
Looking at the assembly instructions it was quite straight forward, some desoldering and drilling. Everything was going well until i noticed this,
The cable from the micro-controller to the I/O board was too short. The J7 cable was too short also so both had to be replaced, while not hard it does take quite a while to do.
After that was completed it was time to assemble the kit and drill out the selector knobs a little (these need to be done if the x0xb0x has the original greyhill encoders).
And so we have the finished unit.
Looks really nice don't you think? It's also nice to see that Substyler has taken my design to the next level. The kit was packaged together very nicely and the instructions were clear and concise.
This unit arrived in very poor shape. The case was loose, it would power on but it was impossible to write programs in.
This machine had originally been modified and worked on by a well known circuit bender in the USA, I'll mention no names. They had added individual outputs and a replacement switchboard and frankly done a terrible job of it.
The client had sent the machine back to them several times without any success and eventually decided to send it here.
After disassembling the unit it was apparent how bad a job had been done. Connectors held on by glue? this was not a good sign.
The inside of the case had a lot of battery leakage also.
So it was time for a bath,
and some loving care to restore the unit back to it's former glory. (well except for the purple LEDs of course)
Well here's another iPad demo, again I know its not my normal thing but I thought this app would be interesting for you also. This was released today and is currently on sale at 50% of normal price.
What you get is a software MS-20, SQ-10, a drum machine and a mixer. I guess its comparable to the DS-10 on the Nintendo DS.
I've worked on many MS-20's but never owned one, I've literally only had the software for a few minutes before doing the demo, so it's really just a first look and I'm obviously a little lost with it.
One thing I did test (which I'm sure most of you would be interested in) is the filter. It self resonates as expected but it does sound a little stair cased. I suppose this is to be expected with software, though I honestly don't understand why there isn't some form of slew to combat this.
Still it's quite fun to mess around with and certainly one of those apps to play around with on long trips.
I don't normally do iPad demos but i figured some of you might be interested in this app. It's the Moog Filtatron that was released yesterday.
In the demo I show using the internal oscillator and a couple of drum loops I recorded. There's also a line in option but you'd need something like the iRig to use that which I don't have.
It's a fun app but I'm not sure how much serious use it will get, still at $10 it's hardly a dent in the wallet.
The inspiration for this little jam came from the cool poly mode on the Mono/Poly. When it's set to poly mode and the arpeggiator is running each oscillator is triggered one after the other. Combine that with some x-mod and you can get some nice synth percussion.
I then added an SH-101 bass drum, an MC-202 snare (noise patched in from the SH-101) and additional percussion from the A-100 modular. The A-115-5 is used for the synth bell tones and I'm also using the A-106-1 with self oscillation for a few blips.
The modular was triggered from the TR-606, though this is only used for triggers and not any sounds. All the drums are synthesized.
All that was left was to add a bassline from the TB-303 and record a little jam.
I'm using touchOSC and osculator to control Logic.
Since I'm no longer part of Analog Sweden I'm offering my services for vintage synth repairs, if you had a repair done there over the past 20 months then you'll already know my work.
I'm offering very competitive rates and to get the ball rolling I will beat any competitors quote. So if you are in need of any kind of analog synth repair work drop me a line on info@dinsync.info and let me know what the problem is you are having. I'll get right back to you with my thoughts on what to do or how much it may cost to repair.
I've lots of experience with vintage gear, here's a list of just some of the machines I've worked on over the last 12 months
Arp 2600 Arp Odyssey MKI/MKII/MKIII Jen SX-2000 Korg MS-10 Korg MS-20 Korg MS-50 Korg SQ-10 Korg 900ps Korg Trident Korg Polysix Korg Monopoly Moog Minimoog Moog Memorymoog Oberheim Four Voice/Eight Voice/SEM Oberheim OBX Oberheim OBXa Roland Juno-106 Roland JX3P Roland MC-202 Roland SH-101 Roland SH-2000 Roland System 100 - 101 Roland System 100 - 102 Roland TB-303 Roland TR-606 Roland TR-808 Roland TR-909 Roland VP-330 Sequential Circuits Pro One Sequential Circuits Prophet 5 Sequential Circuits Prophet 2000 Sequential Circuits Prophet T8 Sequential Circuits Prophet VS Yamaha CS-60 Yamaha CS-70
You can wire the LFO outputs direct from the rear of the LFO selection knob at these points. Wire the tip of the jack to the point in question and wire the sleeve of the jack to a convienient ground.
You can wire the oscillator outputs direct from the rear of the source mixer faders at these points. Wire the tip of the jack to the point in question and wire the sleeve of the jack to a convienient ground, with the VCF cutoff cv, add a 100k resistor in line to the tip of the jack. To wire up the triange output, simply wire the tip of the jack to pin 10 on the CEM3340 ic. (this is done exactly the same as it is for the MC202 vesrion of this mod, details here)
work in progress...
all done.
6th September UPDATE
I added this picture of my ground wire (red wire center of the pic.) As you can see theres a nice little ground symbol marked on the control board. I found this to be the best place to take ground from for this mod. Also your connection wires should be shielded wire, leave the ground floating at the pcb end (you'll see mine have some heat shrink tubing to insulate the shield from touching the board and connect the shield at the jack end, this will create nice little rf jackets for your "live" wires. If you don't use shielded wire you'll end up with some bleed through from the circuits.
I hope you are having a nice summer holiday, anyway in my spare time I've made a few modules for my Eurorack. The inspiration for these came from a Quad Slew design from navs modular lab blog. In that article I came across a link to a DIY page by Doepfer which I hadn't seen before. There's plenty of simple projects there and so I set to work and ended up building a Quad Slew, a Dual Inverter, a CV Amplifier, an Audio Mixer and an expansion port for my A-137-2 Wave Multiplier II. And here's the result.
After last weeks post DanG kindly made some more excellent pattern sheets. This time there's one for the TR-606 and two for the TR-808. The TR-808 ones are for 16 or 32 steps, so now you can backup all your patterns. Simply download the sheets and print them out.
Here's a really nice pdf pattern sheet which I got from Dylab, you can download and print out. It has room for all your patch data so you can backup all your favorite basslines, very nice indeed.
Be sure to visit DyLab's blog for more TB-303 related topics.
The sheet was orignally designed by DanG who visits here and had this to add.
I designed those many years ago in Visio and gave them away to peff to distribute. I'm glad someone still finds them useful. :)
You can find the original posting along with a 4 pattern per page version at the bottom of peff's Synthesis Archive page here:
So here's how to modify Korg's new Monotron analog ribbon synthesizer. Perhaps this is the first document of Monotron mods in Europe since it still hasn't been released here.
It's actually a very easy machine to modify because for whatever reason Korg decided to label all the interesting points on the bottom side of the PCB. This may well have been for testing units at the factory/service centers. Perhaps though it could have been that the designers anticipated this little machine would be hacked, much like the Gakken which pretty obviously inspired this piece. Incidentally in the magazine that comes with the Gakken there's a picture of them showing it to Korg, that was in 2008, go figure.
Modification wise everything is simple enough except for the gate. Unfortunately the gate point affects the pitch somewhat. There's a few solutions, the first of which is to use a single pitch cv line into the gate socket. This will work but you wont be able to get really low notes which is less than useful.
After a little research I came across an idea to use a dtc114 transistor to trigger the gate (soldered at a different point). I tried this but didn't have much success. Also that method will result in the LFO not re-triggering which is bad since the LFO is the closest thing to an envelope on the machine.
By far the simplest solution is to use something like Silent Way by Expert Sleepers (see my previous video on this software) or Volta by Motu. After calibration there's no issues whatsoever and the monotron tracks over 5 octaves nicely.
Using an adjustable dc power supply is a good alternative to the batteries and is also useful in getting the Monotron to a decent tuning range, just don't dial in more than 3 volts. I built my power supply based on this schematic
If you intend to use both battery power and dc power you should include some diodes in your design.
And lets not forget the filter, the side of the packaging says "the legendary MS-20 filter" while this is true design wise it would probably be more accurate to say the MS-10 filter since it's only low pass and the MS-20 has low and high pass filters. How does the filter sound? actually very good! I've repaired some MS units and the Monotron really does have some DNA from the MS series, even down to the small noise hiss when the resonance is high but not yet self oscillating.
A couple of things I noticed about the filter input, if you drive the input signal too hard the resonance almost disappears, so be sure not to overdrive it too much if you want the full character of the filter. Also the input jack is stereo which means if you use a Y cable you can run two signals into the filter comfortably. I tested to see if the left side input leaked to the right input and it doesn't at all, which means it really is a true stereo input to the filter which is very nice.
As for the output, even though it's a mono output via a stereo jack the manual states that you shouldn't use a mono jack on the stereo output, so it's probably best to use a stereo jack plug but leaving the ring floating to get a mono signal into your daw/mixer. The output is a little noisy due to the fact that its really a headphone out and the output level is a little low so you will probably want to use a noise gate to remove the noise floor when it's not playing. (this is the same with the Gakken)
That's about it, here's the diagrams for modding, as you can see it's very simple indeed and should be no problem for anyone with soldering skills.
The Monotron should be available to buy in Europe from around the 30th of June for around 50-60 euros.
Here's what's got to be one of the best bargain analog synthesizers out there. It's the Gakken SX-150, a stylophone styled analog that can be found on ebay for $40. The machine has to be assembled, but there's no soldering involved. It's just a matter of putting the PCB in the case and connecting the power line, pretty simple stuff really. It's very much a gimmick but since it really is a true analog it's fairly easy to modify it into something useful.
So here's what I added, for reference I'm looking at the board with the PCB text that reads "hechenggi" in the bottom left.
CV/Gate in:
This one is really simple since the cv is tied to the gate, so you only need to wire in a jack and wire the tip to the south side of R7 and the sleeve to ground.
LFO Inputs and Outputs:
Again very simple, you can tap the LFO outputs from the waveform selection switch, to add an LFO input you need to cut the trace between the waveform switch and the south side of R17. You can then add a toggle switch between these points and wire a jack to one side. You will have to add a resistor to ground for the floating side since as soon as the trace is open the tuning changes. With clever use of a two way toggle you can make it so that the internal LFO is disabled when the switch is up and the resistor is tied to ground only when the internal LFO is off.
Disable Pitch Env:
I did this purely for stability, since sometimes the pitch env is still active a little even when the knob was fully off. You need to cut the trace between the south side of R13 and the north pin of the pitch env pot. You can then wire your toggle between these points. Again you'll need a resistor to ground to keep the tuning correct when the pitch env is disabled. Make sure that the resistor to ground isn't connected when the Pitch Env is enabled or you'll loose most of the range on the Pitch Env pot. Exact resistor sizes for this mod and the previous one will vary depending on your power supply settings and control voltage so it's probably best to get a guitar tuner or something similar and try what sizes work best.
Resonance feedback knob:
Fairly simple, wire a 10k pot (as a variable resistor) to either side of R39. If you want to place the pot where I placed mine you will have to remove the power jack and move a capacitor. I extended the legs of the cap as you can see in the following pictures.
Cutoff range adjustment:
I placed a resistor between the north and west pins of the cutoff pot since as stock the cutoff knob only worked for the last 30% of travel. The resistor helped to fix this, again you'll have to experiment with sizes here (if you need to do this). Start with a large resistor and work down until you find a suitable size.
Adjustable power supply:
You can find details on how to make one here, I just made two in one. I would recommend using precision trim pots so you can fine tune the voltage (don't go over 6v though)
Here's the schematic which is a little simplified but could be useful.
Just thought I'd show you the new version of my DIY sequencer. In the last video I had it mounted in the modular on an old CD cover. This was taking up about 24HP so i decided to shrink it down to 16HP. I had to use two doepfer 8HP blind panels since unfortunately they don't sell 16HP ones.
I put the LED's into a nice new arrangement and added last step switches inpsired by the video response to the last video by Synthetik. I didn't have double throw switches, so I had to use single throw. So at the moment it doesn't work without the pitch knobs being at maximum. I'll add some double throw in the future to fix that and add the ability to remove the step from the sequence. I'll also add a clock trigger circuit so that I can drive it from the modular clock.
Of course I'll post a video with schematics for that once it's done, which will probably be the last work I do on this particular project.
All in all I think it looks a lot better now and is much more sturdy compared to the original CD case panel.
Since I've had a few requests about tap mode I figured I'd make a video showing how to do this on the MC-202, TB-303 and TR-606. All in all it's quite simple to do as you can see. If you are wondering about the weird hand directions when I'm working on the 606 it's because of the camera tripod in the way ;-)
I just bought these excellent plugins so I figured I'd make a quick demonstration of some of the features. The software includes many different plugins that are useful to anyone with modular gear and an audio interface that is DC coupled.
The whole package is simply put, awesome. However one thing to consider is that while the plugins themselves don't have any latency they do use the audio outputs to create the control voltages. What this means is that the control voltage will be delayed by the size of your audio buffer. If you have a host that has plugin delay compensation then you can use the latency fixer tool available free at the Expert Sleepers website which allows you to delay any track by any amount you wish.
Using the latency fixer I was able to get comparable results with the voice controller to my hardware midi to cv interfaces. You can download a time limited demo of Silent Way here
All in all a great package and priced at $50 it's also excellent value.
As you can see from the header above I've added the line "Also featuring eurorack modular synthesis and DIY projects." I figured that it could be nice to officially include that since from last weeks post I can see many of you are interested in modulars and DIY projects.
The old "MODS" tag has been replaced by "DIY" and a new tag "Modular" has been added.
If you've done the MC-202 mods then this could be a nice addition to your setup. The sequencer is very cheap and easy to build, it's based on the "baby 10". I did a few modifications and plan on making more in the future along with a proper front panel for my modular (right now I used an old cd cover).
I think the total cost of the project is around £10-15 pounds, the main cost being the potentiometers. The mods I did to mine are a 4 step switch,a reset button and output attenuation (it was outputting 12 volts which is a bit hot for my gear). There's scope to add switches to disable steps or output the clock pulses, you could even add a mutli switch to set the last step or set ranges on the output. The scope is only limited by your imagination.
Here's the original article that was inspiration for this project.
I'm sure some of you have already seen my custom TB-x0x overlay for my x0xb0x. I made a couple of these with the help of Jeff at Custom Synth. Here's a picture for those that haven't seen them.
The old panel
As you can see the design is based on the TB-303. Now while it looks very nice there's a few problems with it. First its an overlay, which means you have to stick it on your existing panel. Also the overlays weren't 100% perfect when it came to alignment, if you look closely you can see some of the original panel around some of the holes. Finally since its printed onto vinyl the text isn't as sharp as I'd like it to be.
The overall effect is nice, but it could be better. However there is now a silkscreened version thanks to x0xsh0p. Recently Substyler who runs x0xsh0p approached me and asked permission to reproduce my design. In the spirit of the x0xb0x (open source) I of course agreed and I also helped him out with a few photos of my TB-303 to make the logo a little more accurate. Once they were complete he very kindly sent me one free (thanks man!!) and I've just installed it. Here's a picture of the new panel.
The new panel
At first glance of the pictures they look almost the same, but with close inspection you'll see the new panel is silver anodized with a nice black silkscreen. It fits perfect and the text is sharp and clear. And with the new more accurate logos it really takes the old design to a new level. Substyler did a really great job on these and I hear there will also be black versions in the future. So if you are interested in getting one of these or perhaps some other x0xb0x related items drop by Substylers webshop. He has all sorts of x0x stuff in stock including everything you need to build your very own x0xb0x.
This time I'm showing you how to program a Roland MC-202. The tutorial only covers the most basic features but should be enough to get anyone struggling to a good start. In the future I'll do a follow up video showing some of the more advanced features.
If there's something you think I missed or if there's something you want to know more about then leave a comment to this post. I'll do my best to cover what you ask in future posts.
So far from the comments of previous postings I plan to do these videos in the future (not in any particular order)
Advanced track programming on the TB-303 Advanced track programming on the TR-606 Tap mode on the MC-202 Information on my hackintosh Information on my modular Follow up to the x0xb0x vs TB-303
So if you want to suggest soemthing else then this is the place to leave your suggestions ;-)
Just a bit of fun (we all need some fun sometimes huh). Here's a live jam featuring the Roland TB-303, TR-606. TR-808 and TR-909. Recorded in to Logic 9.
This time I'm showing how simple programming a Roland TR-606 is. I show how to write patterns, edit them and set their length. I also show how to write them into tracks.
I hope you are having a nice easter. I am, except for the slight cold I have. So appologies if I sound a bit snotty ;-) Anyway this has been requested a few times so here's how to program tracks on a TB-303. It's a relatively simple operation when you know how.
Making drum sounds with an SH-101 and MC-202 with a little help of a TR-606. So I finally have my studio rebuilt and so I'm able once again to make videos. This time I'm showing how to use the SH-101 and MC-202 as percussion instruments. In the example I'm using a TR-606 to send triggers but you could use any trigger source to do this. If you don't have external triggers you could use the machines internal sequencers to trigger the sounds.
There's going to be a short pause with the videos, the reason for this is that my studio is in a transitional stage. I just built a hackintosh and my old audio interface isn't working with it. A new one has been ordered but it hasn't arrived yet. Hopefully it will arrive sometime next week.
I guess this is a chance for me to reflect on what I'm going to do with the blog in the future. I may add some content related to some of the other machines in my studio since there's only so much I can show on the x0x stuff. We shall see, of course the empasis will still be on the x0x stuff but I think it might not be a bad idea to broaden the horizons a little from time to time. I may well start by adding more stuff about the modular, since thats one of my other passions.
Anyway, things will be moving again very soon so stay tuned.
For the final MC-202 modification in my little series, here's how to add proper cv/gate inputs. In the video I highlight the differences between the internal inputs (which are quantised by the cpu) and the modification.
This mod requires cutting traces, so a little extra care is needed. Be extra careful when working on the gate part since there's not much to solder to around the CPU. You'll have to scrape off some of the mask on the traces and wire direct to them. Take your time on this and be sure you have done it correctly before applying power to the machine.
Here's a two part video looking at the TR-808 features and programming. This is one of my favorite machines, with its pure analog tones and deep bass drum boom.
This week I show how to add more oscillator outputs to your MC-202. These include, Square, Saw and Sub Osc. I also show the possibilites of this and the previous mods with and without an external modular.
Here's a close up look at the Roland SH-101, it's features and how to program it's internal sequencer. I also show how I use it with my Roland TR-606 and Doepfer A100 modular synthesizer.
This time I show how to add some more CV outputs to a Roland MC-202. It's relatively simple, all you need is three 3.5mm jacks and some shielded wire. Schematics are below.
