• Mattson EG/VCA (2 modules)
• Mattson EG/VCA (2 modules)
• Dual Plague Bearer (2 modules)
• CGS Twin Wasp (2 modules)
• Mattson Distributor (4 modules)
• Mattson VC Mixer (1 module)
• CGS Super Psycho LFO (1 module)
• Dual CGS Slope Detector (2 modules)

That’s 16 separate modules in 8U of space!

The 1U panel dimensions are 8.75″ high by 1.725″ wide.  I leave it a little shy of 1 3/4″ wide to assure fit with other modules. I use this size for all 1U panels, not just this format.

The MOTM jack grid of 8 x 2 locations is ubiquitous. Vertical spacing is 1.0″ and horizontal is 0.85″.  I locate the lowest row 0.90″ above the bottom of the panel, which leaves clearance for parts both top and bottom.  Any standard panel component fits: a jack, a pot, an LED, a toggle switch, and even a miniature rotary switch.  Just make the hole the correct size for the part you’re fitting.

The main difference from the standard MOTM format is the small knob.  Although I happen to have used 16mm round Alpha pots for all of these, there is room to fit 12mm square Spectrol pots.

I generally put jacks to the right or below other components.  One reason for this is the use of Bridechamber 3-jack brackets to mount PC boards behind.  I like to use jacks to mount this bracket, but in the case of the Psycho LFO the bracket is mounted behind three pots.  Most of these modules are dual, with one module physically located above the other.  I try to co-locate a knob with its corresponding jack.  A CV attenuator will have its input jack just to the right.

A vertical column of eight small knobs has the downside that you have to look closely when grabbing one, to make sure it’s the intended one.  Naturally, a small knob doesn’t offer the same amount of control as a larger does.  (These are 3/4″ in diameter vs. the 1″ MOTM standard. )  I was willing to give this a try, as a trade-off for the module density, especially for use in the 20U portable cabinets.  I’ve proven the concept now, at least to myself.  Currently my DIY module queue is empty, but no doubt I’ll be considering the use of this format again for future modules.

The other idea was to let some audience members in a close setting participate by using hand-held controllers like the one in the picture to change the sound during the performance, in effect jamming with me.  To this end, I put together the ‘west coast’ box in the picture, containing:

• Cynthia ZerOscillator
• CGS Wave Multiplier and Grinder
• Blacet/Wiard Miniwave
• Two CGS Serge VCS
• CGS Super Psycho LFO
• Dual CGS Slope Detector
• MOTM-800 Envelope Generator
• MOTM-190 Dual VCA
• MOTM-OMS 820 LFO/EG/Lag
• My own Matrix Mixer

I arrived at this combination of modules after a lot of consideration and trial.  The Matrix Mixer allows me to do the mix live without needing an external mixer.  The outputs can go directly to powered speakers.  I was looking for signal purity in this patch and designed it to avoid the need for external mixers, effects, computer interfaces, etc..  I can still run it through any of those if I want to.

The patch shown in the photo uses 9 modules:  the ZO, Wave Multiplier, Grinder, Miniwave, Matrix Mixer, a VCS, a VCA, 820, Psycho LFO.  And only 10 patch cords are used,  not counting the hand controller.  The Slope Detectors and MOTM-800 weren’t used here.

Three signal paths are patched.  1) ZO sine wave through the 190 VCA into the Miniwave (on the Socket Rocket EPROM), 2) ZO morph (variable wave shape) output through the Grinder, 3) ZO triangle through the Wave Multiplier.  The VCS is used as a VCO for linear through-zero modulation of the ZO.  The Psycho LFO modulates the Wave Multiplier.  The 820 is used as an LFO on the VCA to control the depth of the sine going into the Miniwave.  Everything else is hand-twiddled.

This is a performance:  There are no chance elements, only the combination of oscillators and manual operation.  I was pleased with the range of sonic possibilities available from this simple setup.  The title refers to the use of the center position of the BIAS switch on the ZO, which starts the oscillator at zero HZ with an infinite modulation index. Some sections use this setting, while others do not.   The telltale sign of non-zero bias is a more strongly pitched result.  It may be of interest to note that I did not touch the big ZO frequency knob.  Glissando effects all originate in pitch changes of the VCS.

I came up with an idea for audience participation.  It involves handing out two or three controllers to audience members at a live concert in a close setting.  Each controller is patched in somewhere and the participant has to figure out by listening what his/her controller impacts.  Of course I decide in advance what parameters are controlled and set limits on them.

The controllers patch using an insert cable with a TRS plug on one end that breaks out into two cables with TS plugs on the other.  They are color coded red for the input and blue for the output.  It’s like having a pot in the middle of a patch cable.  The big red button has to be held down to enable the pot.  By default, the output is at ground.  When the button is pressed, the output connects to the pot wiper.  So the participant can choose to hold the button and sweep the pot, or to set the pot and press the button to jump to the the pot setting.  I have a couple of 18-foot insert cables, plus a 6-footer for use in the studio.

The enclosure is a Bud box from Mouser, #563-AN-1300.  The button is NKK, Mouser # 633-LP0115CCKw01C.  Pot is an Alpha, Mouser #313-1000F-100K.  Everything fits snugly.  The button makes a loud click, which might be distracting if the passage is quiet.

• Mackie 802-VLZ3 8-input mixer
• Lexicon MPX-1 Multi-effects processor
• TC Electronics Desktop Konnekt6 Firewire Interface
• TASCAM SS-R1 Compact Flash MP3 recorder
• A pair of FMR Really Nice Compressors

Of the many potential ways to hook this stuff together, I’ve come up with this patch.  Have a look at this block diagram.

I’ll describe how this works with the Mackie features to get flexible signal routing.  The first thing to look at is the Matrix Mixer in the upper left.  This is my own Matrix Mixer module.  It can mix up to six signals coming out of the modular and has stereo outputs.  (Most of the arrowed lines on the diagram indicate stereo connections.)  Note how the output of the Matrix Mixer tees off, one branch straight into the Mackie on channels 3-4, and the other going through a compressor and the Lexicon in series into channels 5-6.   Both the compressor and the Lexicon are stereo units, and each has a bypass switch.

Moving down the diagram, note the mono Aux Send output.  This is not pre-patched.  I use it to send signals into the modular for any purpose, but usually to patch modules as effects.  The MOTM-410 filters, Blacet Time Machines, and Blacet StonZ Phaser make very good effects processors.  The outputs from whatever I’ve chosen are then returned to the Mackie channel inputs 1-2, which have equalization and also the ability to mix back into the aux send bus for feedback!

Next, notice how the firewire interface is fed from the Alt Outputs of the Mackie, and is returned on channels 7-8.  I have to explain the alt outputs.  Each input channel on the Mackie has a Mute-Alt button.  In the normal position, the channel signal is routed to the main mixing bus, headed ultimately to the tape recorder and the studio monitor speakers.  But when the Alt button is engaged, the channel is routed to the alt out bus.  The channel fader still controls the level, but now on the alt out.  This means I can mix to the computer any of the three sources:  from Matrix Mixer, from Lexicon effects, and from modular effects.

Remember that each Mackie channel also has an aux send pot that mixes into the Aux Send bus.  (Selecting the ‘pre-fader’ option sends the signal to the aux bus before it reaches the channel fader.)  Are you getting the picture now?  Possibilities include:

• Three parallel effects:  Lexicon, Computer, Modular.
• Lexicon and/or Computer effects followed by a Modular effects.
• Modular effects followed by Computer effects.

A few things I can’t do, such as routing the stereo output of the computer to the stereo input of the Lexicon.  (I have to mix channels 7-8 to the aux send and patch the mono aux send into the Matrix Mixer for that routing order.)  This setup has flexibility that I could have used even before I got the firewire, if only I had thought of it.  I hope this information may be useful to you.  And please add comments!

Getting the Macbook Pro opened up new possibilities for software DAW work, since it is such a great multimedia platform.  All I needed was a way to get audio in and out.  After some research I settled on a TC Electronics Desktop Konnekt6.  It provides two channels in and out.

Desktop Konnekt6

The Konnekt6 comes with Cubase LE4 and nice control panel software.  I really like all of the hands-on control this unit offers.  There’s even a button on the control surface that minimizes and maximizes the control panel on the computer screen.  The big knob is the volume control for playback, as it’s often connected directly to monitor speakers.  I route the output of the Konnekt6 back into my Mackie mixer on a stereo input channel.   That way I can play it back and record it into MP3 on my Tascam, and even add effects from the MPX-1 at that time.

Cubase LE4 is overkill for my needs.  I find it as daunting as Pro Tools was to use, and I don’t have much fun figuring out how to make it do what I want.  The neatest feature I’ve discovered is the built-in VST effects.  I do like to use digital post-processing, for which the Lexicon MPX-1 goes a long way.  Now I’ve got more to explore, if I can find the patience.  In any case, the whole setup works quite well and the Mac interface is great, especially the touchpad!  Not much need for a mouse any more.

Here’s a photo of the setup:

I wanted my own PA system for performances, so as not to depend on house PA systems.  So I purchased a pair of these RCF powered PA speakers.  The RCF is seen below a Mackie HR824 nearfield monitor.  I am able to use either set of speakers – or both at once – in the studio.  The RCF pole-mounts, too.

The ART 310-A speaker is bi-amplified:  300 watt low and 50 watt high into a 10-inch woofer and 1-inch tweeter.  Uses balanced XLR input with a through XLR output (handy for hooking up the Mackies).

How do these sound?  Really good!  The Mackies seem to have more definition, but not as much open quality as the RCF.  The speakers sound different from each other, but it’s hard to describe.  The RCF exhibits a little hiss from the tweeter when quiescent.  But I have no complaints.  They will do the job in a club or gallery.  And they are light:  under 30 pounds each.

Here is a perspective of the left side.

And of the right side.

Here is a close up of the cabinet loaded for digital processing.  The modules from left to right are:  MOTM-120R Sub-Octave Multiplexer, MOTM-390 Dual LFO, Bridechamber Multiples, CGS Digital Logic, CGS Dual Burst Generator, MOTM-730 Voltage Controlled Divider.

http://www.fmraudio.com/RNC1773.HTM

Two of them fit really nicely in this Funk Logic 1U rack panel.

http://www.funklogic.com/NCC-1701.htm

I had 1U of open rack space in my recording accessory rack.  Now it’s full. The photo shows from top to bottom:

Furman PL-PLUS II Power Conditioner

Dual FMR RNC

Lexicon MPX-1 Multiple Effects Processor

Tascam SS-R1 Compact Flash Recorder

Each RNC is a stereo compressor/limiter.  I patched the first one (on the left in the photo) using TRS patch cords into the insert jacks of the first two inputs of my Mackie mixer, placing it before the signal goes through any EQ and before it is sent to the MPX-1 for effects.  The second RNC is patched between the mixer output and the recorder input.

Compressor effects are subtle, as they impact the envelope (amplitude) of the signal.  One reason I want compression is to get control over spikes in amplitude that can happen during auto-chaotic music of the sort that I make.  I also want to explore what kinds of effects they might be capable of.  The RNC has a side-chain path, which allows patching a filter or other processor between the input signal and the envelope detection circuit.  I plan to try this out with the left RNC, the one on the input side.

A third cabinet holds the Furman power conditioner, the Lexicon MPX-1 Multi-Effects Processor, and the Tascam SS-R1 compact flash recorder.

R10UE-10

These are nice, strong cases that hold 20U width of MOTM modules.  I outfitted them with Synthesis Technology MOTM-19A mounting rails.  One of the cabinets has a Power One HAA15-0.8-AG +/-15 volt supply, and the other a Power One HTAA-16W-A triple voltage supply with +5V.  These use MOTM-960 and MOTM-990 power distribution boards, respectively.

The depth worked out nicely, with plenty of room in front of the supply for normal MOTM modules.  There’s even enough clearance for a Stooge 3-pot long bracket (below).

I built the power supplies into aluminum box enclosures for safety, so that no 120V AC wiring is exposed.  The box and cover are Digi-Key parts 377-1028-ND and 377-1047-ND.  I found a combination AC inlet, power switch and fuse, Schurter IEC320 AC I, (Mouser 693-4304.6090) for $9.00.  It takes the same type of fuses as the MOTM-900/950 (Littlefuse 0239.800HXP for USA), but fuses both sides of the AC line so you need two.  The enclosure is mounted on a 3U high blank aluminum rack panel.  The whole unit is just another rack-mountable item.  It’s essential to use an aluminum panel, not steel, because of the machining required to cut the large rectangular hole for the power connector.  I drilled 20 small holes in the enclosure to allow some ventilation, and the whole box being fastened to a big panel also provides conductive heat dissipation, which I hope will be sufficient.  On the HAA15 supply the jumpers labeled VW1 and VW2 near the output terminals have to be cut to change from +/-12 to +/-15 volts (thanks to Paul Schreiber for this tip).