[b]signing out – for now..[/b]
Once again – thank you all!
I think I have a far better understanding now about what Theremin players want – from both ‘extremes’ – I will go away and have something of a re-evaluation, and then get on with producing the first prototypes. I have also just landed a contract for a months PSoC consultancy work, and this should relieve my finances a bit and keep me solvent for the next few months.. so here are my ideas about what I plan for the next few months – these may change..
[b]Antennas:[/b]
My original plan (which was at quite an advanced stage in development) was to have 2 identical sensors for pitch + volume – I had designed and prototyped the mechanical features (brass support poles, self contained sensor assembly, the ability to move / rotate the sensors so that either could take any orientation – allowing them to be positioned for conventional playing or desktop + wearable use) but the need to increase the size of the sensor plate (to increase the range) makes this scheme difficult / impossible.. I already have the biggest housings for the sensors which can work with this scheme..
So.. Redesign of the antennas is now my top priority – My thoughts are that I will now place the sensor electronics in the main box, and have exchangeable passive antennas to allow the various (conflicting) ‘requirements’ to be handled. There are some (fairly minor) design issues to overcome – the main one being the fact that having a passive antenna system increases stray capacitance, and extra care is needed with screening connection to the sensitive area on the antennas – I also need to devise new methods to implement directional fields – although this should not be too difficult – A directional antenna will probably now consist of a plastic tubular antenna with appropriate screening layered within it.
Having passive antennas will reduce the cost ( the active antennas and the mechanical assembly for these was elegant and real flash – but horrendously expensive – The cost of a full set of all antenna options should still be cheaper than a pair of active antennas)
[b] Linearity [/b]
I have now calculated the cost of including variable field linearity, and it comes to about £2 – I think I will include this as standard – it will be a screwdriver accessible preset potentiometer, so it can be set to the players preference, and left.. This will give an adjustment range from ‘natural’ (inverse square law, or 1/C2) at one extreme, to ‘standard’ (The curve from a standard inductive oscillator, which is about 1/C1.5) to linear at the other extreme.. This will only be applied to the pitch antenna – the volume antenna will be linear.. I hope that this will make everyone happy!
[b] “Handedness”[/b]
I am looking at ‘keying’ the antennas, so that the assignment of pitch will automatically follow the side to which the pitch antenna is fitted – this would avoid needing a switch… All comes down to whether I can include this with little extra cost – which comes down to what spare logic gates etc I may have.
[b] Preview [/b]
I intend now to include a separate preview output, with separate level control and on/off – I will not be fitting a visual pitch indicator unless I get a lot of requests for this.
[b] Octaves [/b]
There will be a switch selector (Probably PSoC CAPSENSE) to select number of octaves in sensing field and to select / transpose the lowest octave in the sensing field.
[b] Synthesiser / sound source[/b]
I intend to stick with a full-blown analogue synthesiser for (at least) the first prototype – This section is almost completed (some of the PCB’s have even been designed) – this will also give me an evaluation platform, from which to decide what is really needed (for example, whether I need a heterodyning sound source, or whether the classic Theremin sound can be produced with subtractive synthesis).
I can more easily remove elements than add them (having all the o