Joined: Dec 23, 2005 Posts: 4127 Location: Mount Hope, KS USA
Audio files: 96
Posted: Thu Nov 20, 2008 8:16 pm Post subject:
Well, the inverted outs are more of a luxury - usually a modular has something that'll invert a signal anyway. They're just provided mainly because, for the price of a resistor, they can be.
What's missing are the voltage permutations I'd planned, which is one reason why there's an expansion socket for future development. A Wiard JAG would seriously rock with an Appendage or two driving its inputs. _________________ My Site
Well, the inverted outs are more of a luxury - usually a modular has something that'll invert a signal anyway. They're just provided mainly because, for the price of a resistor, they can be.
Aye - which consequently is why it'd be silly not to bring them to the panel for the price of a minijack and some wire, then our inverters are freed up for other duties.
Scott Stites wrote:
What's missing are the voltage permutations I'd planned, which is one reason why there's an expansion socket for future development. A Wiard JAG would seriously rock with an Appendage or two driving its inputs.
Won't all the different mixing options and inverted outs take care of most of those permutations, though?
Joined: Dec 23, 2005 Posts: 4127 Location: Mount Hope, KS USA
Audio files: 96
Posted: Fri Nov 21, 2008 12:18 pm Post subject:
Well, the permutations, which involve the bend voltage mostly, perform certain functions that simple mixing won't be able to reproduce. Mainly, they involve limiting the movement of the bend voltage to positive slides, but not negative slides and vice versa, with inversion.
For example - the positive bend permutation would go positive as one would slide above the initial point of contact, but remain at zero volts when one would slide down past the initial point of contact. Say you have your filter cutoff controlled by the bend voltage, sliding up would open the filter, then sliding back down to the initial contact, then past it, wouldn't close the filter any more. The bend voltage will do pretty much the same thing if you're using it to control a VCA (two quadrant multiplier). As you slide up, bend would open the VCA, as you slide down to the initial point of contact, the VCA would close down. Below the initial point of contact, the voltage goes negative, which would keep the VCA closed. Inverted bend would open the VCA as you slid down past the initial point of contact.
A min/max (peak/trough) module could be patched to do the same thing.
Interestingly, if you're using a DC coupled ring modulator (four quadrant controller), you could patch an LFO into one input and the bend into the other input. Bend could then control not only the amplitude of the LFO, but the phase of the LFO - slide up would be non-inverted LFO, slide down would be inverted. If you were using only initial voltage to control pitch (like in my first video), the slide would only be apparent as added modulation to the signal. You could hit a note, slide up a bit and bring in a sawtooth, then slide down, fade out the sawtooth, and, as you keep sliding down, phase in an inverted sawtooth. In fact, pitch control is really just one way of using the Appendage - it's perfectly happy controlling other things while you control pitch with something else...
But the permutations (and much more) still exist as a gleam in our eyes with the expansion port.
the first Idea that i had when looking to the videos today was:
would it be possible to take a small softpot, say 10cm, as a trigger pad,
and a long softpot, say 50cm, as a pitchpad ?
this way you could make a kind of a Guitar or Bass ( i was Bassguitarplayer btw.)
take this 4 times and you have a kind of an electric 4 string bassguitar.
(sorry if this was allready brought up, i read not the whole thraed )
Joined: Dec 23, 2005 Posts: 4127 Location: Mount Hope, KS USA
Audio files: 96
Posted: Sun Nov 23, 2008 3:10 pm Post subject:
Quote:
the first Idea that i had when looking to the videos today was:
would it be possible to take a small softpot, say 10cm, as a trigger pad,
and a long softpot, say 50cm, as a pitchpad ?
You mean one Appendage board for the separate trigger and pitch pad? Probably not - the functions are inextricably tied together. In order to get the pitch, internally you use the same signal that generates the gate and trigger. I'd think some of those cool little pressure pads and a simple circuit would get you there pretty quickly, though.
I've been working on the "Exposed" doc this weekend - it might make that a bit clearer.
This morning I shot this video. It's using the mixed output for pitch of the VCOs - a large amount of initial and a small amount of bend. The TFS is controlling a VCA that's feeding an LFO back to the modulation input of the Appendage. So, basically, modulation index is controlled by the distance between two points of pressure, with one point of pressure being zero.
Joined: Dec 23, 2005 Posts: 4127 Location: Mount Hope, KS USA
Audio files: 96
Posted: Mon Nov 24, 2008 9:56 am Post subject:
Here's a video I whacked out last night - it uses the external sample and hold function.
The sample and hold function uses the internal S&H system of the Appendage to process an external voltage rather than the voltage provided at the tap of the ribbon. The Initial Voltage signal acts as a sample and hold. The Slide and Bend voltage signals act as track and holds. The Slide output delivers the track/hold at the level input, the bend output delivers the track/hold with an offset equal to the Initial Voltage. The TFS voltage still works in the same manner (it is not affected by the S&H mode of operation).
There are three S&H modes:
Mode 1 only samples when the ribbon is first pressed. Initial and Bend track as long as the ribbon is pressed, and hold when pressure is released.
Mode 2 uses an external clock input. Nothing happens until the ribbon is pressed. When the ribbon is pressed, and the external clock input is high, the Initial voltage takes its sample, and as long as the ribbon is pressed and the external clock is high, slide and bend track. When the gate drops low as the ribbon is pressed, or when pressure is removed from the ribbon, the slide and bend voltages hold. Pretty much any LFO can serve as the clock input, or even some other device, such as a sequencer gate output or keyboard gate output.
Mode 3 acts as a "normal" S&H - an external clock signal clocks the S&H regardless of whether the ribbon is pressed or not.
There is an additional "special" S&H input function that provides a different internal routing and allows the input to utilize the AutoGlide function based upon a change in the input voltage - this is provided for synchronization of AutoGlide with external keyboards and sequencers, etc.
This is a quick and dirty sample using the noise output of a Blacet DSC2000. The Appendage is in S&H Mode 1. Bend, Initial and TFS are mixed together, and the mixed output is controlling the pitch of the VCO. The Initial Output is patched to the filter as well, controlling cutoff frequency. The trigger output only is connected to the EG, and the Appendage is in HyperTrigger mode.
I spelled "instantaneous" wrong, BTW. Just so's you know I know...
Joined: Apr 17, 2006 Posts: 2810 Location: New York
Audio files: 24
Posted: Tue Nov 25, 2008 5:52 pm Post subject:
Scott,
Fantastic video illustrations Scott. Thanks ! I think this would fit in very nicely for a demo at Stony Brook University here in New York when this is turned into a manufactured product. I plan to do that and also do demonstrations at the next Analog Heaven 2009 in New England this spring like I did with the EM Klee 2 this past year !!!
Speaking of manufactured product, I am pleased to announce that the prototype "Appendage Touch Controller" PC Boards have arrived, four of them, for the prototype build portion of the project. Four complete parts kits are nearly together and 500 mm Soft-Pots have been shipped to me from Sparkfun Electronics and will receive them in a couple of days.
The picture you see is the board with a template over the top side to act as guide for the component placement since there is no silkscreen on these test boards. It weighs in at 8.5" x 4" and houses all the Appendage features and features connectivity to many popular synthesizer power connector standards such as PAIA (FRAC), Blacet, MOTM, Doepfer A100 (Doepfer CV and TRIGGERS are also brought in), Dot COM, and two user connectors including a terminal block for flying lead connections to your power source. A 20 Pin expansion header is also provided for all manner of experimentation such as digital quantization of the Appendage's key signals so they may be transmitted over MIDI or even OSC (Open Sound Control) devices via Ethernet to OSC compatible hosts.
Bill
DSC01432.JPG
Description:
Filesize:
1.54 MB
Viewed:
242 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.
Joined: Aug 03, 2005 Posts: 176 Location: chicago/peru,illinois usa
Posted: Tue Nov 25, 2008 8:02 pm Post subject:
WoW the board looks intimidating for a ribbon controller you and Scott must have put in a lot of work for this to happen (cant wait !!!) _________________ mY MusIc
http://www.myspace.com/toyboxbastard
Joined: Apr 17, 2006 Posts: 2810 Location: New York
Audio files: 24
Posted: Wed Nov 26, 2008 10:28 am Post subject:
Quote:
Great looking board, I am getting that itchin' feeling. Many thanks for the addition of the OSC interface.
Ringer,
Thanks. The expansion or AUX connector as it's called on the card wil allow for this if one chooses. The physical media for data transport would most likely be Ethernet and incorporate an ENC28J60 based MAC/PHY chip from Microchip. Sparkfun Electronics sells a breakout board with the RJ45 connector, magnetics, LINK/ACTIVE LED's, and this MAC/PHY chip all on one small carrier. The challenge is learning the "OSC" protocol and knowing which hosts utilize the OSC data ,and, what data they use. With OSC, you can even encapsulate MIDI data in the message payload BUT also utilize it advanced features with all it's fancy addressing schemes and data types. I am sure this will take lots of research.
Right now, we are interested mainly in getting these prototypes tested, and production ready boards completed.
Posted: Wed Nov 26, 2008 10:58 am Post subject:
Proto PCB
Hey Scott & Bill,
Wow, what a great job on the proto PCB. I'll bet you could use another 55 gallon drum of midnight oil to burn. That is some tedious layout job, but it is guaranteed to be worth the effort. You guys have a real winner here
Joined: Aug 03, 2005 Posts: 176 Location: chicago/peru,illinois usa
Posted: Wed Nov 26, 2008 8:10 pm Post subject:
wow!! Tim your video was grate it was nice to see every thing put together into the mix this project just gets better everyday _________________ mY MusIc
http://www.myspace.com/toyboxbastard
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
Forum index » DIY Hardware and Software
FAQ
Calendar
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
Chat Room
