I had a rough start to the working week last week, so a bit of retail therapy was in order. Going to my favourite hock shop I saw this with a $299 price tag. A piece of 1973 ancient history/juvenilia from one of the most iconic synth makers of all time; a bizarre unique design (and nomenclature); a very good price; and a cool FX pedal to boot? Hell yes!
Electroacoustical Electromusical Excavations
WHEN FLEACORE MEETS FLAWCORE
Saturday 29 October 2022
Cat in a Can
Saturday 1 January 2022
BBD and me
Sunday 18 July 2021
Oh, your hype is beautiful, oh the price...I C O N I C
Well, in a coda to my Tandy Tampura article of last year, and echoing my sentiments in the article, it appears that the home of hype and greed in the service of the price inflation of music gear has decreed that this rhythm box is now "iconic", with "sonic territories" waiting to be explored (and presumably prices to be gouged) by issuing a sample pack. It's hilarious that they try to make you believe this was ever worth 24 bucks, when it takes longer for you to read the legal terms and conditions PDF than it probably did for a person to assemble this entire "extensive" sample package, but here it is.
You honestly can't make this stuff up. Bonus points for recording a piece of 40-year old consumer-grade ephemera with a recording setup you could probably use for classical music recording. Says it all about the vintage gear hype cycle, really!
Wednesday 14 July 2021
When people sell fake parts as new it makes me a very SAD Panda (plus MXR shMXR)
Here is a close up of the deceased piece of metal-oxide coated silicon in question.
So...despite being out of production for decades, this chip appears to be for sale in bulk lots from China, at high prices, as "new". Normally I wouldn't go near the Chinese aftermarket for silicon, as chips pulled from electronics recycling are often sold as new, and sometimes chips are even relabelled to look like more expensive and desirable models-which doesn't make them work like the more expensive brethren!
Sunday 11 July 2021
Zing went the strings
As mentioned before, I have a Roland RS09. Recently I took advantage of an online sale to add a Behringer VC340 to my collection. It seems to be the universal opinion that the VC340 *is* the reincarnation of the Roland Vocoder Plus version 2, and I'm very happy with it. I realised I now own two of the "big three" 1978-9 stringer designs by Roland, the other being the now-ridiculously-overpriced Paraphonic 505. These broke the mould of triple chorus "Solina wannabes" set bv the earlier RS202 stringer, introducing Roland's own four-chorus take on the ensemble effect. So putting aside the considerable differences in other aspects of their designs, what are their differences as stringers? No-one seems to have done a direct comparison of all three, there is misinformation around, and some comparisons have an almost comical confirmation bias towards expensive purchases, so here goes.
Note 1: all schematics are the 1979 "rocker tab" versions which all used SAD512 BBDs in the ensemble circuit. These chips are now very expensive to replace if they die!
Note 2: Sustain in the schematics is actually "release" on the panels and in modern parlance.
Mode I means that pressing a key while another is held will not cut off any note tails that are still sounding, but pressing a key after all others have been released will cancel all sounding notes. This is useful for vocoders or paraphony where you do not want note smearing when the VCF envelope (or the speech signal) re-articulates.
Mode II means that note tails will not get interrupted by new notes, and is best for pretty much anything else.
Note 3: Ensemble Mode I: animated from slow triangle LFOs and fast sine LFOs both being applied (think classic stringer)
Ensemble Mode II: slow sweeps from just the slow triangle LFOs (think goth icescapes like the Cure's Funeral Party)
Ensemble Mode III: Mode I but with feedback loops on the right and left chorus groups, meant to emulate rotary speakers but sounds more flanger-ish
Parameter | RS09 Organ/Strings mk1 | Vocoder Plus mk1 | Paraphonic 505 |
---|---|---|---|
Schematic date | Dec 78 | Sep 79 | Sep 78 |
US Price 1979 | $795 | $2695 | $1695 |
Keys | 44 | 49 | 49 |
Keysplit | none | upper/lower | upper/lower |
Master Oscillator transpose | Octave down switch, fixed /2 divider | variable bend slider, range adjustable up to an octave down | variable bend slider, range adjustable up to an octave down |
Master Oscillator divider ranges | 8',4',2',1' | 8',4' | 8',4' 16' (bass only) |
Ensemble modes | I,II | I | I,II,III |
Ensemble LFO rates | 6.7 sec, 5.5 sec 210ms, 170ms | 3.9 sec, 4.6 sec 150ms, 175ms | 6 sec, 7 sec 160ms, 180ms |
Ensemble external inputs | Yes | Vocoder carrier only | Yes |
String assign to Ensemble | switchable on/off | fixed on | fixed on |
String footages and waveshapes | 4'- 3-bit saw 8'- 4-bit saw summed from divided square waves, "log curve" global waveshaping | 4' - spaced sharktooth circuit on each key | 4', 8' - spaced sharktooth circuit on each key |
String filters | high on 4' tabswitch low on 8' tabswitch | global | high on upper tabswitch, low on lower tabswitch |
String footage selection | two tabswitches | none | 4'<-> 8' cross-fader into each filter |
String LFO vibrato | yes | no, vocoder and voice vibrato modulated via SAD1024 BBD delay | yes |
Release modes | I,II (panel switch) | I (fixed) | I,II (Mode II only engaged on connection of footswitch) |
Polyphonic Release control | yes, release start level, foot switch control | yes, release start level, no foot switch | yes, true variable release time, foot switch control |
Paraphonic attack control | yes, strings only | yes, independent for strings and voice | yes, strings only |
Tone control | yes, pre-main output, common with organ | yes, individual pre-chorus | yes, post-chorus, on back panel |
Synth connections | gatebus out, "raw organ" (unfiltered) out | No | gatebus out, trigger out (retriggers on additional keypresses) |
Phones out | yes, stereo, master fade | yes, mono, separate fade, transformer isolated | none |
As can be seen, there is surprising commonality between the RS09 and its (then and now) expensive siblings, even surpassing them in some respects. All three can effectively layer other sections to "thicken up" the strings' low end-the RS09 has organ, the Vocoder has 8' human voice, and the RS505 has an actual mono bass section. Interesting also to note that the prices are for sure a reflection of a time when electronics cost far more than the metal-and-woodwork that housed it, as the lightweight, utilitarian RS09 was not that much cheaper than the deluxe wood-cased RS505.
Also interesting to note that both the most expensive and cheapest of these three survived into the 80s in a revised version with touch switch controls and updated Panasonic MN BBD chips, and the RS505 didn't. Maybe on the eve of affordable true polysynths (the Jupiter 4 was out at the same time for $2795), the RS505, with its "synth" section with just a single VCF that didn't track the keyboard and a single VCA, simply turned out to be neither fish nor fowl.
Moreover, for about the same price people could have had an RS09 and an SH09 synth combo, which for roughly the same price could either provide strings and a mono bass/lead with filter tracking and actual portamento, or when patched together, paraphonic filter and VCA articulation.
The RS09's low price earned it thousands of sales, a place on all three of the Cure's "dark trilogy" of 17 Seconds, Faith and Pornography, and even a failed, market-misreading spinoff in the Saturn 09 organ (ah Roland, you've done it again!). The fact that layering the organ onto the strings along with Mode II ensemble gives a passable synth-like pad sound would not have hurt the RS09's sales, either.
As for the Vocoder Plus, the string section was obviously a cheap and easy add-on to the insanely complex vocoder that, along with its unique analogue voice synth (hey, why not add another 7 bandpass filters while we're at it?), gave it the ability to replace the Mellotrons of the rich and famous on tour, and earning it a place in the rigs of people who never even used the vocoder, like Tony Banks. The vocoder does feature on 80s hits both groundbreaking (O Superman and Behind the Mask) and timelessly cheesy (Mr Roboto).
To close with a bit of subjectivity, if you can get a good deal on it, the Behringer VC340 is well worth the asking price, and better value new than any of the above after 40 years of use, as well as adding DIN and USB midi control. It sounds "off" through a mono signal chain, but godlike if you can keep in in stereo and keep levels well down to avoid overloading artifacts.
Friday 19 June 2020
Maxon Payne 2
I first tried applying a 6-layer thick square onto the pedal foam to add enough contact pressure to switch the pedal. No dice. Then I added a further 4 layers of duct tape.
Success!! The pedal switched over - just- at the bottom of its travel. Screwed the switch in, clicked it a few times-then it stopped clicking. Time for more tape. I added another 9 layers, when it started working, then another three more for good measure. It worked, but again, it eventually stopped changing over the switch as the foam block "adapted". Argh.
And of course with all of this insertion and removal of the switch, one of the flimsy wires to the switch carrier board snapped! Murphy's Law in action, and time for more soldering.....
Tuesday 16 June 2020
The Joy of Forgetting
Although it appeared a bit beaten-up and well-used, it seemed to be in one piece, so I asked the staff what the price was. $29. Instant buy.
The original pedal was indeed designed by David Cockerell in 1978, and was very interesting. It employed an obscure RCA transconducting op-amp (CA3094) extensively, and had some innovative ideas. For example, the "subharmonic" generator was actually a chopper timed by what the pedal's circuitry saw as the fundamental harmonic waveform. The chopper signal silenced the original signal during every second cycle for a subharmonic with traces of the original harmonic structure. Its square wave output (a pre-filtered saturation distortion) had the input signal's amplitude envelope re-imposed on it. The octave output was not time-based, but actually a full-wave rectifier with high-pass filtering. There was a threshold-triggered variable attack generator controlling a VCA.
Icing on the cake, it had an 18dB lowpass VCF with resonance whose control source defied both received guitar pedal wisdom (from the 70s until now, preferred logic is that filters should follow the input signal amplitude envelope ie Moogerfooger LPF and Maxon Autofilter) and received synth-head wisdom (filters should be controlled by an envelope generator with defined rise then fall times ie Moogerfooger MuRF). Instead, input signal threshold triggers a linear ramp generator with arbitrary start and stop levels, and a time control.
So, I got it home and turned it on. All seemed to work. The slider travel seemed a little rough but there was no noise or dropouts when I moved them. However, there was no filter motion at all-no matter what the settings, the filter was stuck tracking the stop level slider. Oh well, maybe it broke and that's why it was hocked for so little. Let's take a look.
The board inside is (nearly) all surface mount, with the prominent exception of tantalum caps (Y tho????), and looked very different from the 1978 schematic-and not just in the absence of CA3094s. The board did not seem to be very logically laid out, either. I put it aside to work on other things.
Yesterday I found that a brave soul (Bernard d'Uur) had actually made a trace of the schematic for this revised modern reissue. Yay! A few things were apparent. Not just the OTAs switching to 13700s, but much of the circuit had been revised. Gone were the nice dual 12V power supplies, now there was a cheap and nasty op-amp rail-split of the 9V signal to give virtual ground at 4.5V (c'mon EHX, even hobbyists know to use the LT1054 charge pump IC to get dual 9V supplies!), and the circuits appeared to have been cheapened a lot-gone were the zener references and a lot of the OTAs, replaced by generic transistors, generic signal diodes and resistors in paralleled configurations. In short it looked like a design that had the hallmarks of a synth designer (whose design language was typical late-1970s) had been re-imagined by guitar pedal guys (whose design language often seems stuck in 1967!). Still, the filter circuit seemed intact, despite the current design cheaping out on ceramic caps rather than film.
So, I got to work. Still working on the assumption that the pedal had broken after purchase, I suspected that one of the many signal vias (courtesy of the haphazard-seeming layout) was to blame. With expansion of the many fibreglass layers in a PCB, signal via traces running between board layers can be vulnerable to failure, which is why they they are often filled with epoxy, solder (better), or soldered solid wire contacting the top and bottom pads of the board (NASA standard!) to guarantee longevity.
I noticed that there were empty part positions, largely to accommodate through-hole versions of parts where no SMT equivalent was available at time of design, such as JFETs and some capacitors, and set to getting the board out of the case.
At this point it was apparent that it was not designed for field servicing, as the jack sockets would not allow the board to be easily removed. I eventually pried each side by increments with a small screwdriver, and it was free.
Looking at the front, it was clear how dirty the board was from use, probably due to a total absence of dust filters on the slider runs (cmon, EHX!).
I returned to Bernard's schematic, and decided to start looking around the ramp generator, starting from the timing capacitor C6. Ummm, what timing capacitor????
The filter ramp timing cap had never been fitted at the factory!!! This explained why the filter was static alright, and it must have been the case that the guitarist who bought this just shrugged their shoulders and simply used it as a glorified fuzzbox. Still, it begs the question of what sort of quality control something that new currently costs $A600 deserves-there were no quality control stickers on the board or inside the unit.....
The solution was a nice fat tantalum cap scrounged from a prototype I had to hand and soldered in seconds. First switch on-yay!
The 18dB filter squelched beautifully, and with ye old Concertmate drum machine I was in heaven.
Conclusions: Quality control matters. Having any parts such as tantalum caps that can be assembled by machines, assembled by machines, is A Good Idea. Not leaving multiple empty part positions on your boards so that hand assemblers don't get confused when visually checking the parts that should be there, is A Good Idea. Designing your PCBs so the layout is logical and aids service, like Roland analogue synths, is A Good Idea. And when troubleshooting, don't ignore the obvious, assume cost equals quality, or discount human stupidity :)
Cat in a Can
I had a rough start to the working week last week, so a bit of retail therapy was in order. Going to my favourite hock shop I saw this with...
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As mentioned before, I have a Roland RS09. Recently I took advantage of an online sale to add a Behringer VC340 to my collection. It seems...
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Once upon a time in the 1990s, a dear friend and former university classmate, who had been playing guitar since the 70s, gave me an old guit...
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I had a rough start to the working week last week, so a bit of retail therapy was in order. Going to my favourite hock shop I saw this with...