Using an encoder on the control port for up/down gain?

Joechace

Is it possible to use an optical or mechanical ecoder to control up/down gain throught the control port of a BLU-100? If so how? If not any ideas other than using a pot?

mupi2k

The gist of what you want to do is discussed here: http://www.bssaudio.com/phpBB2/viewtopic.php?t=575

If you take your gain control, and convert it to a spin control (so you have the Up/Down buttons on your control panel instead of a knob) you will then be able to take the up button, and link it to one port, the down button linked to another port, and presto.

Now if you have physical switches for up and down, it's easy. with a rotary encoder, depending on type, it's slightly harder, but as long as you can just get an \"up\" click or a \"down\" click output it will work. (a lot of rotary encoders I have seen, for whatever reason, don't simply output \"up\" and \"down\", you have to see which side pulses first. For \"up\", pin 1 pulses, then 2, for down, 2 pulses, then 1...I don't think the logic layer can respond quickly enough to determine direction of rotation in this fashion.)

Joechace

Thanks.

The up/down switch configuration works. Is there a way to set the step level? On my control panel I set the properties so that each push is a 1db step. With the control prot switches the step seems to be .38db. Can this be changed?

Thanks again
Joe

Dan Lynch

That's really weird. You just said \"Thanks\" for advice that was wrong. This entire paragraph is incorrect:

If you take your gain control, and convert it to a spin control (so you have the Up/Down buttons on your control panel instead of a knob) you will then be able to take the up button, and link it to one port, the down button linked to another port, and presto.

If you create a SpinInc or SpinDec button on a control panel just so that you can drag it to a control port, all you've done is waste the time it took you to create the SpinInc or SpinDec. If you drag a fader, a rotary, a SpinInc, or a SpinDec to a control port, you'll see a \"Mode\" selector at the bottom of the dialog box. That selector is the only thing that determines how the control port will work. The function of the control port is not determined in any way by the type of control used to drag the state variable onto the control port. If you select Analogue Input, the control port will be looking for a variable resistance (a pot). If you select Up/Down Pair, the state variable to will be mapped to two consecutive control ports with the first port being UP and the second port being DOWN.

To answer your more recent question, no. There's no way to set the step size on a control port that's mapped as Up/Down pair. That's because there is no step size. The state variable continues to go up or down as long as the contacts are closed. So, .38 dB isn't something that has been set somewhere. It's just how far the fader happens to move during the time when your contacts are closed. Make the contacts stay closed longer and the fader will move further.

Dan

{edit} Somebody emailed asking if I knew of an encoder with a contact time that could be adjusted. Unfortunately, I don't. They're usually designed with a really short contact time because a short contact time means potentially more contacts per second.