Data switch box and Probox

[AustinFa04]

Hello,

I recently ordered a ProBox ( Thanks to Ralph for his excellent service to us for that), but I also still use my D8B as an audio input device for recording into my DAW. I am aware that while connected to the Probox I can only use it as a DAW controller and not a audio throughput, however rather than disconnecting the DSUB for the Pro Box and reconnecting to the Consoles computer every time I wanted to switch between the two, I purchased a parallel 24pin DSUB data switch box and an additional 24Pin DSUB connector cable (m/m) so that I can switch between the two seamlessly.

So here is my issue...

When connected up to the switch box, the console and the computer do not seem to be communicating with one another (Host not found).

Is there a pin configuration difference that anyone is aware of?

[Jondav1120]

Hi Austin,

The D8B data cable carries two serial links in a non standard pin configuration, so if your switch box is for a single serial connection it probably will not work. What you need is a parallel printer switch box which switches all the pins.
I don't have a probox, so I can't provide you with a link to a switch that is known to work, but I'm sure someone will be able to help on that one!

Regards

John

[AustinFa04]

Thanks for the response...

here is the one I picked up. as far as I can tell, it is a Parallel Serial D-Sub 25 Pin switch box.

https://www.amazon.com/gp/product/B07KW ... UTF8&psc=1

If it is a configuration issue, I could probable just open up the box and change that myself if needed, just need to know what the D8Bs data cable configuration is.

[Jondav1120]

No idea if that switch box will work or not, but if you are handy with a soldering iron and don't mind opening the box up, it could probably be rewired to work providing the rotary switch has enough 'poles'.
Ralph would probably know which pins need to be switched.

Regards

John

[AustinFa04]

Okay, thanks!

I'll shoot him an email, get his input (no pun intended)

Thanks again!

[Y-my-R]

I'm using a DB25 switch that looks exactly like that one (but I'm not sure of the brand - it doesn't say) and it works fine to switch the D8B between Mixer and ProBox operation.

I asked Ralph about using a switch some years back, and he basically only told me that the switch needs to have a 1:1 pinout for all the pins, and that some of those switches don't have all the pins connected and that then would not work.
He also told me that he personally only runs the D8B with the ProBox (and not as a mixer), so he has no need for such a switch, but heard that some people had good success with switching between the ProBox and the D8B as a mixer.

I can confirm that, and you can even pass audio through the D8B while using it with the ProBox by doing the following (once the switch works):
1. Boot the D8B in mixer mode and make all the routing and level settings you need
2. Switch the DB25 to ProBox operation (via the external DB25 switch)
Result: Most of the time this works fine and audio continues to pass through the D8B... however, every now and then the levels (or "invisible faders") on the Mixer-Side get reset to all the way down (minus infinity), and no audio passes. When that happens, you have to switch back to mixer mode, set the levels again, and try switching to ProBox mode again until it works as expected.

As for what's wrong with your DB25 switch... it could of course be the switch, but since mine looks exactly like the one on the amazon shop page you shared (I bought mine at Fry's years ago), I suspect it should be the same on the inside, and you just didn't hook up the cables right.

Here's how you wire it:
DB25 on D8B RACK UNIT => Switch DB25 Port A
DB25 on ProBox => Switch DB25 Port B
DB25 on D8B CONSOLE => Switch DB25 Port "I/O"

If it still doesn't work with this wiring for you, also try the two DB25 cables you have for use with the switch, directly between the D8B Console and Rack unit. If one of them doesn't work when connected directly, the entire switch configuration won't work. So, make sure you have two DB25 cables that work with the D8B directly, before trying to use it with the switch. Those also don't all have a 1:1 pinout, so one of those cables might be the culprit, too.