Idea for Theremin Staccato Pedal

Posted: 8/31/2014 3:13:32 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"...(this is IMO the greatest challenge for digital - getting the UI right! - A challenge they have mostly failed on with musical instruments)"  - FredM

One approach I find attractive is that taken on the Waldorf Micro Q and the DigiTech RP1000: a control matrix which consists of encoders for the columns and some kind of selector / LEDs for the rows.  In a sense the menus are physically printed on the control panel, which gives a lot more info than normally found on a small or middling LCD.

Posted: 8/31/2014 3:51:43 PM
GordonC

From: Croxley Green, Hertfordshire, UK

Joined: 10/5/2005

OK - constant sustain level isn't really an issue for the pedal - I can use the volume loop to vary volume slowly during he sustain phase - "loop droop" if you like. :-)

Would a mini-prog be useful to me? Programming was one of the first things I had to give up when I contracted M.E. - it brings on my "mind-fog" symptoms symptoms almost instantly - every year or so I have a go at coding something in a language I am familiar with (i.e. Forth or LOGO - I never got into C) and then have a long lie-down until my head clears. It's rather galling, as programming was my favourite thing to do. :-(

And yes, I would like an analogue interface - pots for A, D, S and R, a capacitive plate trigger and a push button to invert the operation of the trigger (i.e foot-on triggers release, foot-off triggers attack + decay.)

Posted: 8/31/2014 7:15:40 PM
FredM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as WaveCrafter.com . ...................................

Joined: 12/7/2007

Hello Gordon,

Sorry - I had forgotten about your ME issue - not nice! .. The Mini-Prog probably wouldn't be much use for anyone except the developer.. The API's are all in C and ASM, and only a C compiler and Assembler are available, so C really is the only choice (Or C++ which is also supported I believe by the GNU compiler - not something Ive looked into as I dont do C++)

"And yes, I would like an analogue interface - pots for A, D, S and R, a capacitive plate trigger and a push button to invert the operation of the trigger (i.e foot-on triggers release, foot-off triggers attack + decay.)"

Below are all the envelope selection options:

 

You can select any one 'normal' and any one 'inverted' from the above, and have the logic enable these under control of one switch (normal / invert )

Alternatively you could have 2 switches, one to select waveform polarity (normal / invert) and one to set pad / sensor polarity (active pressed / active unpressed).

The possible (4) combinations are paired left to right.

The choice is yours ;-) (I suspect you want 10 for normal, and 01 for inverted - 3rd column from left))

ADSR pots should easily be catered for by ADC / AMUX, and capacitive actuation should be easily catered for by shielded CapSense.

Problems? None that I can see - but that means nearly nowt! ..  I m a complete novice on PSoC 4 (and everything except PSoC 1) - getting into it rapidly, but so far been focusing on the PLD blocks and a bit of its analogue.. I have NOT messed with CapSense at all on this part (so cannot say from personal experience how good or otherwise it is - all I can go on is what I have seen others do with it and from documentation and it looks good), not yet played with the ADC (this should be a breeze, but again I have no experience), done almost nothing with the Cortex (again, almost no experience with it or the GNU tools, but others seem to get on ok .. The MCU side is not my forte though - I expect more difficulty here than with other stuff), and quite literally have merely scratched the top surface slightly - have not even gone deep into the PLD's (data-paths etc)

<deleted an OT chunk>

What I suppose I am saying is that if you cannot find anyone to configure and code your project, I will probably, in a month or so, be able to help a little bit .. I have no plans for CapSense on my project but will probably be reading a thermistor with the ADC (I have one pin left, so may end up using this for something else and doing temperature compensation off-chip)

At present though I am not able to undertake the PSoC4 pedal design.. I am in the manic throes of trying to save myself from financial oblivion (see below)  (Now deleted) and cannot afford to digress too much.

Fred.

<deleted an OT chunk>

Posted: 8/31/2014 8:58:08 PM
RS Theremin

From: 60 mi. N of San Diego CA

Joined: 2/15/2005

I don't know what happened to my first try, I know there are forces that move about?

Ok Fred I will keep you in my prayers... but remember the last time I offered an olive branch you burned down the orchard. 0-'

Christopher

Posted: 8/31/2014 9:25:10 PM
FredM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as WaveCrafter.com . ...................................

Joined: 12/7/2007

OT

"Ok Fred I will keep you in my prayers... but remember the last time I offered an olive branch you burned down the orchard. 0-'" - Christopher

Chris,

Keep your prayers for others.. I requested good vibes from friends - we are not friends by any definition I know. Oh, others will see this as me being nasty.. Its not meant to be. Its just recognition of the reality. I dont accept olive branches when they are wrapped in thorns! "Fred I will keep you in my prayers" could have been touching, and could have been seen as an olive branch -  but the other words showed them to be a Trojan.

You and I dont have particularly endearing feelings towards each other - we may not wish each other ill, but to pretend ... Nah, I cant even be bothered to continue.

Can we just leave it at the above? You have loads of admirers, we have completely different attitudes to everything, and you remind me of my ex-wife.. We have been at war more than any other "estranged couple" at TW .. so lets keep personal contact to a minimum and not say false things for the benefit of mediators, solicitors, judges and onlookers!

I do wish id never posted that silly request "so if you are a friend, I need good vibes through the aether waves now more than ever!" or disclosed the other technical ambitions! (none of which was related in any way to you) - This is the problem when a large percentage of ones "social life" (or at least contact with those who are interested in "your" topic) is on-line .. One wants to open up, but in so doing one becomes vulnerable (or exposes ones vulnerability). I should just keep the lid on it all and stew..

<I have now deleted the sources of potential aggravation>

Fred.

Posted: 9/1/2014 1:39:48 AM
FredM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as WaveCrafter.com . ...................................

Joined: 12/7/2007

OT

"One approach I find attractive is that taken on the Waldorf Micro Q and the DigiTech RP1000: a control matrix which consists of encoders for the columns and some kind of selector / LEDs for the rows.  In a sense the menus are physically printed on the control panel, which gives a lot more info than normally found on a small or middling LCD." - Dewster.

Yes, I agree.. I much prefer those to any other digital interfaces I have used. I HATE the Roland D110 and Yamaha TX16W "interfaces" - My Virus is a mix of (loads of) encoders and menus bit its not instinctive to me, and the Korg Karma isnt friendly either IMO.. Anything display / menu based system, even if it has encoders, disgruntles me.. I find I assign the encoders to some basic functions, dont mess with the menus, and limit my access to much of what the instrument can offer.

But the best IMO are the analogue style ones with loads of encoders (Like the Behringer BCR2000) - at a little over £100 (retail)  I have even thought about just having MIDI for control functions and supplying a customized BCR 2000 for the UI ;-) ... Couldnt buy the 32 good quality illuminated rotary encoders for that price!

I use my Behringer to bypass the damn menus on synths - I would buy one for each of my digital synths if I could afford to (or had the space - even when I had the money, space was the problem.. and now space is critical.. couldn't cram another jack plug into my "bedroom" LOL ;-)

Posted: 9/1/2014 2:21:19 AM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"Couldnt buy the 32 good quality illuminated rotary encoders for that price!"  - FredM

I don't understand why an encoder + 16 LEDs isn't the default solution for just about everything - particularly for things with presets.  I have to shake my head every time I twist a pot to register (and tragically / ironically simultaneously forget) what its position was supposed to be indicating in the first place. 

Maybe we all just need USB jacks in the backs of our necks (http://www.imdb.com/title/tt0100152/).

Posted: 9/1/2014 2:54:37 AM
FredM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as WaveCrafter.com . ...................................

Joined: 12/7/2007

OT

"I don't understand why an encoder + 16 LEDs isn't the default solution for just about everything" - Dewster

Yeah - Now theres a market waiting to be tapped! Simple bolt-in encoder/LED units, perhaps with I2C or similar interface - mini hex switches on the back to set the address (or a chaining scheme so the first encoder has address 0, the next 1, the next 2.. A couple of fast serial lines back to the MCU, perhaps a line for IRQ generation..

Would we ( the small volume buyer) get them at under $8 each ? Fat chance! .. How Behringer does it (lets see, wholesale cant be more than £60 , therefore manufacture cant be more than £40, even if 50% of the cost was the encoders, this is 32 encoders for £20! £1.60 each! ... But with the case and electronics and PSU etc, I would be surprised if the encoders actually clocked in at more than 80p... And I have hugely underplayed the realistic mark-ups .. We are possibly talking about encoders costing more like 40p each.

You cant get a basic gray code switch for that! (even in quantities of 1k) ... I recon that buying a BCR200 (at retail price) , gutting it and building the synth / theremin / whatever into it, you would save about £200 on the cost of encoders / knobs / case... Probably more if you could hijack the existing electronics to do some of your tasks...

For me its a serious option - The BCR2000 is solidly built - a case of equal quality could easily cost £50..

But the 'matrix' style UI (Waldorf etc) you mentioned, with led ring on each encoder, is the next best.. Only 8 encoders needed on a 4x8 grid.. that could perhaps clock in at <£100.

The only minor disadvantage with the above is that each encoder can only be assigned to one of the functions in the matrix vertical to it - if you want an encoder assigned to one vertical column and another assigned to another function in this same column, you cannot do that.

Having say encoders freely assignable to any function, and having a display above each encoder which shows the selected function - perhaps that could work well.. Something close is available on my Karma, but the function of the encoders is shown on the small LCD and not directly above each encoder, and the LCD simultaneously swamps one with irrelevant other stuff - Also, 8 encoders isnt enough for me - I want a minimum of 16 ;-)

8 encoders would just be enough for something like a pedal ;-)

Fred

 

Posted: 9/2/2014 9:34:52 AM
GordonC

From: Croxley Green, Hertfordshire, UK

Joined: 10/5/2005

Hi Fred,

It took me a while and some googling to figure out what an inverted envelope is good for - seems it isn't much use for applying to amplitude, but it is useful for applying to a filter. As this pedal controls amplitude I don't see any benefit from having an inverted envelope. However it did occur to me that a reversed envelope could be of use. Illustration below shows what I mean by a reversed envelope...

 

So, two switches - one to reverse the envelope as above, and one to reverse the trigger logic (foot down = note on, foot up = note off OR foot down = note off, foot up = note on.) And no more features after this!!!

As all the PSoC programmers that I know are participating in this thread, and as I have plenty of patience, I am happy to wait for you, Fred. :-)

 

 

Posted: 9/2/2014 11:31:45 AM
FredM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as WaveCrafter.com . ...................................

Joined: 12/7/2007

"It took me a while and some googling to figure out what an inverted envelope is good for - seems it isn't much use for applying to amplitude, but it is useful for applying to a filter." - Gordon

LOL ;-)

Gordon, now I am REALLY confused! ;-)

I thought I understood what you wanted, and the reason you wanted inverse envelope.. (not a reverse envelope ;-)

Right at the start of this thread, I thought you wanted to interrupt the audio (as in, apply an inverted envelope which, rather than behaving in the normal way amplitude envelopes do, reduced the amplitude during the attack, and brought it back to full volume [with this volume being controlled by the loop, as it is in over-all control of maximum volume] at the end of release).

"It also seems reasonable to me to have the capacitive field operate in the same way as the volume loop, so that the closer the foot gets to it, the quieter the sound, so that playing it means punctuating a continuous sound with brief silences, rather than being able to tap out very short notes. And also so that the player can move his or her foot away from it and continue playing. Other than that, it should have a topology suited to articulation - i.e. a very small, very snappy field - the opposite of what is required for expressive loop playing." - Gordon, first page of this thread ;-)

I believed that positive (normal) amplitude envelope (where volume increases during attack, and drops to mute at the end of release) was the inverse of what you were really after - Something I had almost talked you into including! ;-)

Anyway - none of the above matters .. Its all possible / available, and if going for a configurable device like the PSoC, even if there is still any misunderstanding, there is a far better chance that severe frustration can be avoided ;-)

.. I know you are really patient (unlike me ;-) - But I fear that the length of time it will take before I could start on the pedal might even test your patience a but far.. I am manically working (apart from time I spend at TW and solicitors and courts and benefits offices and doctors and accountants and .. ;-) on the thing I said I had walked away from (and believed myself when I said it! ) - Constructing the high-end theremin hopefully to fill the E-Pro hole.. This time (like all the other times )-8 it looks like it may be within by grasp and even my budget, thanks to being able to pack more than 50% of it into the PSoC4. The result of this effort will hopefully be my salvation - but whether this pans out or not, it will certainly give me deep hands-on experience with this part..

Last time I took on a major project and opted for PSoC 1, the learning caused me to become the first Cypress Semiconductor independent approved consultant in the UK.. Cypress then went and blew everything by changing their tool-chain (to PSoC Express) and pissing off all their customers and my clients (and me!) - I was left working with the old unsupported tools (PSoC Developer) which 5 years later they re-introduced because they had lost so much business, and dumped their asinine unusable PSoC Express.

The memory of their appalling behavior and lack of support, and the huge financial losses I incurred as a result, caused me to stay away from Cypress for many years.. They contacted me a few years ago, saying they needed us "old school" guys back on board - they gave me a full development kit for their new PSoC3 and PSoC5, but these sat on my shelf for years - I had spent >£5k on PSoC1 kit which they had crippled, I want going to be fooled again.

Then they sent me the PSoC4 DK - And more importantly PSoC Creator came up to scratch - And I got a bit interested... Now this £3 board has appeared (after having bought a couple, I got another free in the post ;-) and I have got into PSoC Creator and its SUPERB (The original PSoC Designer was superb - one of the best pieces of development software I have ever used - then they completely F**Ked it - now its back as well, better than before).

"As all the PSoC programmers that I know are participating in this thread, and as I have plenty of patience, I am happy to wait for you, Fred. :-)"

I suppose what I am long-windedly saying is that it seems im back "on board" with Cypress.. But once bitten... There were some big problems with PSoC1 and PSoC Designer in the days long ago - The compiler was absolute crap, and I ended up writing everything in ASM - and many things I had to go real deep into the system to fix (in particular, the analogue stuff was impossible and specifications for many modules were verging on being lies - I ended up reverse engineering the switched capacitor section, putting this into a simulator, and re-writing the API's to make it usable - and in the process discovered that the phases of clocks in this section had been wrongly documented... But I was a LOT brighter back then - If I faced the same kind of problems now, the board would go in the bin!)

I will certainly gain enough experience to be able to do your pedal - and the adoption of PSoC4 CapSense by major manufacturers leads me to believe there wont be problems in that area.. As for when.. Well, if I have big problems doing my theremin in PSoC4 (I am cramming it full, so its a real test) and give it up, I will probably know enough and have time enough to start your pedal in 6 weeks and complete it in a day.. If the theremin goes well, I may be able to start your pedal in a few months.. If the theremin is difficult but not impossible, then it comes first - because I must generate a revenue stream somehow - I cannot really afford development beyond this year unless I sell things like my Tannoys and some synths and by perhaps March  I will have nothing  left to sell.. And as it is I dont know where I will be living beyond January.

So it might be a long wait! - I hope not.. but it might be.

Fred.

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