Joystick for combined balance and fader

[kellyhd51]

I provide both sound and music for our local community theater. For sound effects, I would like to be able to position and / or move sounds among four speakers located (essentially) at the four corners of the room. The speakers are identical and are driven by Crown D 75a's (one for the backstage and one for the rear of auditorium speaker pairs). Would it be possible to wire a joystick with which I could accomplish this? At present, I am "able" to do this awkwardly using the Crown volume controls, but it's akin to trying to use two "Etch-a-Sketch" toys simultaneously. Also, I usually have more than a one task to perform at any given time, so the single, two-finger operation of a joystick would be fantastic.

Having stereo capability would be nice but I would think unnecessarily complex. Therefore, mono (or summed) sounds would have to suffice.

Thanks in advance for any and all help.

 

[Pano]

Sure, why not? The trick though is that you'll probably want audio taper pots for this, any off the shelf joystick might have linear. Been awhile since I've torn one apart. Someone here will know. There are ways to cheat a linear pot into log (audio) that might work.

Many years ago I did a theater tour in which we took 2 channels in, and sent them to 24 speakers around the audience. I used the direct outputs of a 24 channel Soundcraft console to control it. Turning up the volume of any fader made the audio go to that speaker. It was quite a handfull! You could do the same with 4 faders, it would not be difficult. But the joystick would be easier to use.

EDIT: Been too long since I used a joystick controller. 2 pots, not 4 - duh. Here's one:
https://www.adafruit.com/product/3102
You would connect the signal to the center of each pot, then connect the amps to the outside points of each pot. Signal goes in the center terminal, comes out the left or right. 10K is a good value.

 

[ICG]

The Joystick is a good idea. They are linear and one pot per axis though, you'll have to design the electronics for it.

Not as comfortable but easier to build would be two crossfaders, one connected after the other. Unlike at a mixer just use them the other way, one input to four outputs. That way you just have to deal with two pots, one r/l and one front/back, just position the r/l horizontally and the other vertically. The drawback is, you still need two hands and it's much less intuive than the joystick. On the plus side, you can easier and more precise return to a former position.

 

[Pano]

The Joystick is a good idea. They are linear and one pot per axis though, you'll have to design the electronics for it.

I was thinking of a mono signal fed to the wiper of each pot. The ends of the pots would then go to the amp inputs. Sort of 2 balance controls.
When the joystick is centered, the signal goes equally everywhere. Pushed into another position, the signal goes to those amps proportionality.

Not sure how sensitive it would be, or not be.

 

[kellyhd51]

Thank you both!!

Not being an electronic whiz, I think I'm just going to buy one of the joysticks for which you provided the link, and just try some experimental wiring. It would seem that each of the four amp inputs would be connected to one end of both potentiometers to represent the four "diagonal" quadrants (FL, FR, RL, RR).

I would also have thought that there would be a requirement to have a parallel "shunt" to ground along with a series connection to each of the four channels, but I'll breadboard it and give the various options a try. One nice things about working with old Crown amps and Altec speakers is that they tend to forgive user stupidity.

I fully realize that I could have used two linear faders to accomplish the same task, but it's rare that I can afford BOTH of my hands to a specific task at the same time.

Thanks again, and I'll let you know how the experimentation goes providing I don't blow too many fingernails off in the process!

Howie

 

[ICG]

I was thinking of a mono signal fed to the wiper of each pot. The ends of the pots would then go to the amp inputs. Sort of 2 balance controls.
When the joystick is centered, the signal goes equally everywhere. Pushed into another position, the signal goes to those amps proportionality.

Not sure how sensitive it would be, or not be.

The devil is in the detail (like always). You can use the joystick for r/l ofcourse (or f/b, doesn't matter). But then you have two outputs and only one pot left. How you are going to connect the 2nd potentiometer?

 

[bob4]

google "quadrophonic panning", for example:

https://www.gearslutz.com/board/live-sound/177565-live-quadraphonic-mixing.html

https://www.muffwiggler.com/forum/viewtopic.php?t=71326&sid=bf334665a4bc6a144ef98ee58f0ae7e2

https://www.modulargrid.net/e/tags/view/22

a little modular synth setup might be the way to go, although a bit pricey. Still cheaper than a DM1000 or yamaha 02V

 

[ICG]

The problem has been mentioned here. Just try to visualize it, the idea is to put the signal on the wiper and take the signal on both ends for the two channels, right? After the first pot (in -> wiper) it comes out of two pins which got each the signal for right and left, each with its own signal level. Now you have to feed these two to the one pot left. But you only have one potentiometer left, so what will you connect? You can only distribute one of the r/l channels to the back or front with the 'signal on wiper, out at each ends' method. If you want to distribute the signal uneven to the back channels, you need another potentiometer or you have to reduce it to simply one back channel but that would mean the placement in the room would be very limited.

All the solutions which work got either 3 or 4 pots or use electronics to distribute the signal in different signal strengths to all four speakers.

 

[Pano]

Well you basically want to divide the signal according to the position of the stick. A single pot can do that between two outputs, but the 10K impedance isn't going to make a great divider with typical amp input impedance. 100K, maybe. That's what I meant about limited sensitivity.

Looking forward to reading about the results.

 

[ICG]

Well you basically want to divide the signal according to the position of the stick. A single pot can do that between two outputs,

Yes, it can. But that's not what's needed. You want to divert these with the joystick (2 pots) to the outputs. So my question to you (and all the others saying it works with 2 pots): You feed the signal into the first wiper, that gives you two outputs (r/l). But HOW are you going to connect these two outputs on a single potentiometer to get the f/b output or in other words, distribution onto four channels?

I'm sure it doesn't work (without electronics), you keep telling it works. So, if it works, please tell (or better, make a diagram) how.

 

[brig001]

You could do it with an 2 faders, one for x and one for y. Say, single gang for X and a double gang for y. Wire the x as a standard balance control with the wiper grounded (Google this - I can't draw one now as I'm on my phone). Each output from this can go to the second y fader wired as two balance controls with grounded wipers. You could arrange the faders in a box so one is left/right and the other is up/down like an inverted T (or even a regular T thinking about it). This isn't quite as intuitive to use as a joystick, but would be considerably easier than your current setup.

I'll try to add drawings later to clarify this.

Hope it makes sense,
Brian

 

[Pano]

See post #4

 

[brig001]

Yes I did, but grounding the wipers allows it to attenuate fully as against feeding the signal to the wipers where you could never get zero output on any channel. Only a small change, granted

 

[Pano]

Well in a 10K pot it may be what's needed. 100K or 500K would throw the signal a lot more to one side or the other.

 

[ICG]

You could do it with an 2 faders, one for x and one for y. Say, single gang for X and a double gang for y.

Yes, but the whole point was the claim it can be done with the joystick in the linke above with two single potentiometers. I already confirmed myself it works with 3 potentiometers.

I'll try to add drawings later to clarify this.

Thanks, no need for that.

 

[brig001]

Yes, but the whole point was the claim it can be done with the joystick in the linke above with two single potentiometers. I already confirmed myself it works with 3 potentiometers

Sorry, missed that. The problem I can see is that the joysticks that I have used do not utilise the full travel of the pot. This would allow some panning, but not right into the corners. The ends could be trimmed electronically or some method of reading the pot and operating digital pots could be devised. This would also solve the problem of getting two pots operated from one axis.