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Topic: Motorized Faders Linked to Computer Timecode (Read 620 times) previous topic - next topic

buildafriend

Hi,

I have an arduino uno and a motorized fader. How can I make a motorized fader that links to and moves with the timecode of a program like pro tools?

I have one of these:
https://www.sparkfun.com/products/10976

Thanks,
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

pylon

Quote
I have an arduino uno and a motorized fader.
That not a fader, that's a motorized linear potentiometer.

Quote
How can I make a motorized fader that links to and moves with the timecode of a program like pro tools?
I guess you should first solve the problem of getting that timecode data out of your "pro tools". Once you have that solution you should make a "fader" out of your potentiometer. Then we think about how to control that from your Arduino.

cosmicbackground

If we were talking about audio editing software I'd say your best bet would be to do it over midi (good arduino shields and well developed libraries already in place) as these apps would all make it very easy to keyframe/create envelopes for midi output - but Im not sure if the same applies to pro tools? What sorts of parameters a natively assignable to envelopes or keyframe events?

buildafriend

Oh that linear motorized pot isn't a fader? This is why this forum sucks, because of answers like that.

What are faders made out of? Maybe they ARE  potentiometers. And clearly that one has motor. That's why I picked it.

Your advice will be omitted from my intake.
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

buildafriend

I'm not trying to make a midi controller
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

JohnLincoln

#5
Oct 12, 2017, 06:09 am Last Edit: Oct 12, 2017, 01:21 pm by JohnLincoln
Oh that linear motorized pot isn't a fader? This is why this forum sucks, because of answers like that.

What are faders made out of? Maybe they ARE  potentiometers. And clearly that one has motor. That's why I picked it.

Your advice will be omitted from my intake.
You're not going to build many friends here with that attitude, buildafriend.

FYI:   Faders for audio applications require a logarithmic potentiometer.  Pylon was kindly trying to inform you that yours was a linear potentiometer.

cosmicbackground

#6
Oct 12, 2017, 07:08 pm Last Edit: Oct 12, 2017, 08:06 pm by cosmicbackground
I'm not trying to make a midi controller
I'm aware of that -- and I'm going to assume the curtness of your response was spillover from your reaction to the fader vs pot comment.

If this is an A/V application it stands to reason that controlling the movement of the pot may be accomplished most easily, both in terms of requisite circuits and coding, by taking advantage of midi. Using midi as a means to transmit the pot's motor control signals != "building a midi controller". Things that simply receive and respond to midi input are not midi controllers.

buildafriend

#7
Oct 13, 2017, 12:36 am Last Edit: Oct 13, 2017, 12:47 am by buildafriend
You're not going to build many friends here with that attitude, buildafriend.

FYI:   Faders for audio applications require a logarithmic potentiometer.  Pylon was kindly trying to inform you that yours was a linear potentiometer.
this is not 100% accurate. there are tons of different uses for pots and faders in audio applications. you may only be familiar with what you've seen. call it a fader or a pot it does not matter. its carbon or conducive plastic with a wiper sliding around it. you can also apply voltage dividers into your pots to create sweet spots but this is not the purpose of this post. this is simply trivial and basic crap.

I'm glad you guys could let me teach you about this. Does anyone have an answer to my original question?

Do large format consoles use MIDI to control their motorized faders?
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

allanhurst

#8
Oct 13, 2017, 12:45 am Last Edit: Oct 13, 2017, 12:57 am by allanhurst
We  did this back in the mid 70's  at  Neve - the 'flying faders' technology has been around for a long time.  And our computer was a Data General 'Naked mini' iwth core memory... a modern small arduino is probably of similar power.

You can now buy such motorised pots from several sources. Some have linear motors.

If you want to do the mechanical work yourself by all means have a try - it isn't easy.

The control part is trivial by comparison.

And - to answer one of your questions - no . The early versions synchronised fader movements to SMPTE time code  on one of the tracks of a multi-track audio tape recorder. I think professional versions still use a similar technique.

Allan

Delta_G

#9
Oct 13, 2017, 12:48 am Last Edit: Oct 13, 2017, 12:50 am by Delta_G
Does anyone have an answer to my original question?
I do.  But you've really kind of been a jerk so far and I don't want to get mixed up with some flame war if it isn't just exactly what you were looking for.  I wouldn't post at all, but I thought it might help you see why all the folks with the real answers have been avoiding your thread.  Maybe a little bit of an attitude change and getting over yourself just a little would get them back.  Maybe not. 
If at first you don't succeed, up - home - sudo - enter.

buildafriend

#10
Oct 13, 2017, 01:02 am Last Edit: Oct 13, 2017, 01:12 am by buildafriend
allan,

I've been experimenting with verilog, FPGA/CPLD technology, and the Xilinx ISE with the spartan line of chips while using Simon Monks book. I'm glad to see you have found great use for FPGAs and it seems like you could be a wealth of information for me. I have read what you are talking about with the Neve pots from a guy named Ian Thompson Bell who also used to work there. I've also read this in douglas self's small signal audio design book. I believe he was also busy in england back in the day. Ian posts in another forum. It does seem trivial to get this automation thing going since there are different paths. I'm sorry for seeming irritable if at all towards you there is just so much bad advice out there that it really does become troublesome to find good information. The mechanical end of it is no issue for me since my 3D design work seems to generally work out fine as well as my PCB design. There is a nice maker space only blocks from me.

Might I trouble you by asking which path you would take? The best advice I have been given so far is the following - But I'm still figuring out how to interpret it.

"You'll need to do something with the correct sample rate to read the pulses of SMPTE packets and save the state in an array. Then you parse the array to determine the time. After that, what you do with the time is up to you."

I would appreciate any advice from you. It's surprising that these things are still using STMTE. Part of me thought this would have faded with the use of tape machines.

-J
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

buildafriend

okay heres some info..

https://blog.etcconnect.com/2017/02/time-smpte-works/
It's not a matter of what can or can't be accomplished. It's a matter of how much time you have in conjunction with your willingness, and budget.

allanhurst

#12
Oct 13, 2017, 01:31 am Last Edit: Oct 13, 2017, 01:44 am by allanhurst
I've no idea if SMPTE code is still used ( it counted in frames : 24,25 or 30 per second - confusing, eh?)

 - I've been out of that industry for a long time - I did say 'similar' - you'd need some sort of timing reference.

Is your problem then just interfacing to such a standard time reference?

Remember an arduino has a very limited memory - you'll need a means of storing pot(s)  movements against this time reference  and over-writing that when the operator over-rides the previously stored sequence. SD card perhaps ? 

Note I don't use the word 'engineer' for such a person...  I bet few of them even know Ohms's law!


Allan

ps regards to Ian!

Delta_G

#13
Oct 13, 2017, 01:45 am Last Edit: Oct 13, 2017, 01:59 am by Delta_G
I'm sorry for seeming irritable if at all towards you there is just so much bad advice out there that it really does become troublesome to find good information.
How does being a dick to people help you get better information?  Just curious.
If at first you don't succeed, up - home - sudo - enter.

allanhurst

#14
Oct 13, 2017, 01:58 am Last Edit: Oct 13, 2017, 02:07 am by allanhurst
I concur.

I'm trying to be helpful and polite - but  I do hope you'll improve your attitude,  buildafriend, if you want want much help from the many high-grade professionals on this forum.

We don't wave credentials and degrees around, but you can bet there are plenty.

Allan

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