POWERING EURORACK "R" MODULES:
Please, do NOT cheap out on power supplies for Metasonix R modules. You're spending serious money on modules, so nickel-and-diming on the cabinet or power supply is a really bad idea.
R modules pull a LOT of current when powered up cold. You want tubes, this is part of it. Tubes briefly draw more current when they are cold, because the cathode heater in a tube has lower electrical resistance when cold than when hot. It's not like most analog solid-state gear, which draws the same power all the time.
Modern lightweight "switching" power supplies don't like this sort of "cold inrush" current, because they usually have no excess current capacity, and will only deliver exactly what they are rated to deliver. The tube heaters draw about 2 to 2.5 times more current when cold. In the "old days", electronics were powered with primitive linear supplies (usually transformers) which had built-in cold surge capacity, so this was never a problem.
Yes, there are low-power directly-heated subminiature tubes, like the 1J24B tetrode used in the L-1 VCA module. They are quite limited in voltage gain and applications, because they were designed to save power in battery-operated equipment. We use the NOS tubes we use, and not the 1J24B or similar ones, for reasons of performance and availability. Most Metasonix designs can NOT be implemented with low-power tubes.
Linear power supplies, with big fat power transformers and heatsinks, are generally better for running Metasonix modules. Yes, they are heavier, less efficient, and usually more expensive than switching supplies.
For a small system, the Doepfer A-100PSU2 linear supply is recommended. It will run five "regular" R modules, or four R-56 reverb modules, very nicely (although it gets quite hot). We use an A-100PSU2 to burn in R modules before packaging. Doepfer's A-100DIY PSU is also okay, as are their suitcase or "monster" cases that contain these supplies.
If you want to run more modules, especially if you are building your own cabinet, please use oversized power supplies. We strongly recommend Power One/International Power 3-amp linear supplies (or larger). This is an advanced modification, not for beginners. See below.
Or a set of big fat industrial-grade Mean Well switching supplies, the kind used in Monorocket's special cabinet for Metasonix-based systems. (It's a special-order item from Monorocket.) Again, see below.
Linear supplies are generally preferred over switching types, although some switchers are quite high-quality and make good substitutes. If you use switching supplies, overrate them drastically. If you're trying to run five or six R modules, use switching supplies rated for at least 5 amps. Surplus switching supplies are usually okay IF they have ample current ratings, although you should check them for switching/RF noise. In an complex analog electronic system like a modular synth, noisy supply rails can cause all kinds of strange and intermittent problems.
The R-55 needs a good deal of +5v power, as noted. Again, please don't cheap out on this supply. I'm sorry if it bothers you, we are limited to using the 2D21 thyratron in it, which draws a lot of current. Or try our RKP supply system with the optional 5v supply adapter. It will run at least three R-55s.
We do NOT recommend the Tiptop uZeus or Happy Ending kits, even for one R module. They just won't handle the cold load. The Zeus Studio is also not recommended, although it's been claimed to be able to run one R module.
The Makenoise PBB is marginal, it should run one R module, but just barely.
MFB's MIDI/CV converter and power supply combination is not recommended to run Metasonix modules.
Pittsburgh Modular's Cell 48 is not recommended. The Cell 90 will probably run one R module adequately. Pittsburgh's new Move 208 case has a better supply and should run one R module, possibly two.
Cwejman's power supply is an unknown quantity, please check with Cwejman before trying it.
The Doepfer mini-case is okay for a single R module (just barely), but you will have to purchase a larger 9vAC or 12vAC adapter plug to power it. Check with us before trying it.
Regardless of the kind of supply you use, make sure the cabinet is well-ventilated, or at least large enough to handle the excess heat.
DIY OR PROFESSIONAL POWER SUPPLIES FOR METASONIX MODULES:
All of the following will require busboards and some wiring. If you don't know how, get a good technician to do it for you, don't take any risks. If you're a beginner and really don't know where to start, don't experiment; spend the money on a good, preassembled cabinet from Doepfer or Monorocket.
The following suggestions are aimed at experienced DIYers or technicians who want to build a "premium" Eurorack cabinet. They all involve working directly with dangerous AC mains voltages.
A. For best possible performance, linear regulated supplies are strongly recommended. They are large and heavy, and are thus suitable for studio systems not intended for stage use.
*If you don't need a lot of +5v power (and most people don't), the International Power IHBCC512 is excellent and recommended. It will run eight Metasonix R modules easily. This type is available from Mouser and from MPJA.
*For the best possible performance, get the International Power IHDCC-150W or Power-One HDCC-150W-AG. Either has 3.4 amps on +-12v rails and 12 amps from the +5 rail. If you're running R-55 thyratron VCOs, this model is strongly recommended. The two makes are essentially identical electrically but different mechanically. Yes, they can be wired to put out +-15v instead of 12v. This is advanced work, and you have to be an experienced technician to try it. Metasonix R modules can operate on +-15v power, but require dropping resistors to avoid overvoltage on the tube heaters.
These supplies are available from Mouser or from Digi-Key.
B. If you must save weight and space, use good-quality "OEM" switching power supplies. For Eurorack modulars, you will need two 12v supplies, one wired for +12 and the other wired for -12. You can "experiment" with cheaper surplus supplies, but you do this at your own risk. The supplies recommended below are not very costly. In fact, they are cheaper than some of the "powered busboards" on the market. Note that switching supplies, unlike linear ones, do not have any "cold surge" capacity above their maximum ratings, so you must over-rate them heavily to run our vacuum-tube modules.
*For a smaller portable system, we recommend the Mean Well SE-100-12 supply. Two are needed for powering a Euro cabinet. They will run up to ten R modules easily. Available from Mouser or from MPJA. If +5 power is needed also, get a Mean Well SE-100-5, available from Mouser. You can run up to ten R-55 thyratron VCOs from it.
*Building a really big modular? Perhaps you ought to use a pair of Mean Well RSP-750-12. They make 62.5 amps at 12v dc. A pair of these will run more than fifty Metasonix R modules conservatively. Available from Mouser.
POWERING OTHER (standalone) METASONIX PRODUCTS:
Newer products, such as the S-2000 synth and F-1 pedal, include "universal" AC power adapters that can be used on 100-240v ac mains, with only a plug adapter needed for different countries.
Older Metasonix products, including the D-1000, S-1000, KV100, and TM modules, are supplied with AC-AC adapters for use on USA power only--120v, 60Hz. In other countries, having 220-230v 50Hz power, these adapters are NOT USABLE. It is STRONGLY recommended that you obtain an AC-AC adapter made especially for your local AC mains power.
The adapter must produce 12 volts AC ONLY!! DO NOT feed DC power to your Metasonix module--you will DAMAGE IT.
We can recommend some adapters that are available in the UK or Europe, should your dealer not be able to provide the proper adapter. The transformer type commonly used to power 12v halogen lighting is suitable, and widely available.
Some adapters for older products that users in Europe have successfully tried :
Maplin L54BR (for powering one TM module or one KV-100 or D-1000 only)
Block HIT60 (for powering three TM modules, two KV-100's or D-1000s, or one S-1000, requires mains lead and LV power leads)
Conrad 570876 - 62 (for powering three TMs , two KV-100's or D-1000s, or one S-1000, requires LV power leads)
Farnell 1453783 (for TM/TX, one KV100, or one D-1000 - needs 2.1mm connector)
(note: the S-1000 includes the special LV lead required. TM modules, KV100, and D-1000 require a 2.1mm coaxial-plug LV lead, which should be commonly available at any distributor or dealer that sells AC-AC power adapters.)
DOWNLOAD SECTION -- under continuing development
Older products, out of production:
TM-5 manual, GIF format, pages 1 and 8.
TM-5 manual, GIF format, pages 2 and 7.
TM-5 manual, GIF format, pages 3 and 6.
TM-5 manual, GIF format, pages 4 and 5.
The TM manuals above are formatted so that you can print the GIFs out in landscape mode, back-to-back (for example, print TM1manual.gif on one side, TM1manual2.gif on the other), then staple the 2 sheets together (if it is an 8 page manual), fold down the center, and you have a digest-sized manual exactly like the originals.
MIDI-CV converters with Hz/V, making them usable with the Metasonix TM-3 or R-55 VCOs:Synhouse MIDIJACK II (USA)--very small--for special installation
Kenton Pro-Solo (UK)--well-built and flexible
Analogue Systems RS370: an extraordinary complex polyphonic/additive pitch source, arpeggiator, and control system with MIDI-CV and CV-harmonic capability. It is capable of Hz/V control, making it suitable for driving the Metasonix VCOs.
It's not a MIDI-CV, but we wish to recommend the Encore UEG. It is our favorite CV source: it can be a complex envelope generator, a complex LFO, or an 8-step analog sequencer with variable step times. Support Tony, he deserves it.
Hobbyists and DIYers: IF you are experienced in electronic construction, and IF you aren't afraid of high voltages,
there are some basic tube synthesizer circuits by Eric Barbour, on Ken Stone's website.
Why tubes? Read THIS article:
IEEE SPECTRUM, August 1998
495 N. Main Street, PMB 109
Lakeport CA 95453 USA