Bug report of sometimes RTA doesn't show correct SPL

[bcodemz]

Hi John,

I found a bug in V5.20 RC1 where the RTA would show incorrect SPL from the UMIK-1. It usually happens like this. I open REW, use the RTA, and it'll be accurate. Then I'd close the RTA window, but not close REW. I might have unplugged and replugged the UMIK-1 during this time (REW is open all this time). Then when I want to use the RTA again a few hours/days later, I hit the RTA icon again from the REW window that was never closed, and the SPL shown would be about 10dB (rough estimate) too low vs actual. I'm not sure how to reproduce this bug consistently, but I've seen it a few times now.

Thanks

 

[John Mulcahy]

I might have unplugged and replugged the UMIK-1 during this time (REW is open all this time)

Probably best avoiding that.

Are you using Java drivers or an ASIO wrapper? Were the OS input volume settings on the UMIK input left unchanged? What was the input volume? Were any other audio devices disconnected or connected? Was the UMIK on the same USB port?

 

[bcodemz]

Probably best avoiding that.

Are you using Java drivers or an ASIO wrapper? Were the OS input volume settings on the UMIK input left unchanged? What was the input volume? Were any other audio devices disconnected or connected? Was the UMIK on the same USB port?

I'm using Java drivers.

The OS input volume setting on the UMIK is unchanged.

I don't know what you mean by the input volume

No other audio devices were connected or disconnected

The UMIK might have been on a different USB port. I have 2 front USB ports, so I could have plugged into either.

Any recommendations how I could try to reproduce this for you?

 

[John Mulcahy]

Which OS? When devices are disconnected Javasound doesn't cope very well on Windows, it might be better on macOS.

 

[bcodemz]

This is on Windows 10

 

[John Mulcahy]

I'm surprised it work at all, a possibility is that the input reverts to default when the mic is unplugged and so REW no longer treats it as a UMIK and doesn't use the sensitivity figure. If you get it to happen again check what the input settings show in the REW preferences.

 

[bcodemz]

Yeah you're right. I just tested deliberately. When the mic gets unplugged, REW switches to the default input, and the input volume control is disabled. When the UMIK-1 gets plugged back in, it is still on default input, with no input volume control.

 

[John Mulcahy]

OK, should be fine if you just reselect the UMIK input.

 

[bcodemz]

Yup it does work just fine if I reselect it. So it's a Java driver problem that's causing this?

 

[John Mulcahy]

Not really. When you disconnect the mic the input is no longer available so the connection the Java runtime had set up to it no longer functions. The only real option then is to fall back to whatever the default input is.