Can i run 2 SPL meters?

ZachSWR

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I got the multi-input upgrade thinking i could run 2 SPL meters at the same time with 2 mics logging it for comparison of A and C graphs. The upgrade page said that with multi-input, Individual SPL metering is available for the first four inputs. I cant figure out how to get mutiple inputs on the SPL logger. Is this even a feature? I can open 2 instances of REW and get both captures that way but then i shouldnt have bought the upgrade and my logging isnt all in one file. Im on MacOS and runing REW V5.31.3
 
The logger only works on the first input. There are SPL meters for the first 4 inputs in the Tools menu. If you don't want the Pro upgrade you can email me for a refund as long as it was purchased within the last 180 days.
 
Hi, John!

We're making progress and so very close to having REW working the way we want. We're on macOS and starting from a command line with two different prefs files. This is working great and allowing two separate loggers. No issues. We're using --args -prefs <prefs_file.prefs>.

I'd like to be able to script this for the non-technical users whom would run from a terminal. Is there a command line option or, an API option that'll open the SPL meter, calibrate at a given value, then open and start logger?

Everything is working the way we want it- just hoping to make it easier to launch for our servants to be able to start.

Thanks!

-brian
 
Is there a command line option or, an API option that'll open the SPL meter, calibrate at a given value, then open and start logger?
I'm afraid not. Calibration is interactive, so isn't a good candidate to trigger via the API. I can add API spl-meter commands to open and close any of the SPL meters and an API application endpoint to show or hide the SPL logger in the next build.
 
Thank you... Any API calls you can add that I can get to from bash or python will be very helpful!

As for calibration, possible to add a non-interactive mode using an external source?

Our setup is: two RTA mics plugged directly into an Allen & Heath Avantis console at front of house (medium sized church). From the console we route the signal to our Dante network and pick it up on a remote Mac using Dante Virtual Soundcard- no interface, no loopback. We're using an external calibrated signal generator to calibrate to 94dbA. In REW->SPL->Calibrate->External, we set the signal.

I notice that each time I set the signal, the prefs file is updated so I suspect it is being saved. However, on startup, I don't seem to get anything close to accurate readings until I go back to Calibrate (which still reads the correct value) and click OK. Then, all the readings are correct. Not sure if this is my mistake, intended behavior or possibly a bug.

Regardless, we appreciate all your help and anything you can do to further our startup automation. Zach and I are both engineers, we like the terminal and geek out on this kind of stuff but- not so much for our volunteers and leadership!

Thanks again!

-b
 
Calibration offsets are stored per device and, if "Separate cal for each input" is selected, per input channel on the device. The offsets are updated when "Finished" is clicked on the calibration dialog and get saved in the preferences when REW shuts down. If you change the prefs file or start up with a previous version you will lose the cal offset.

I can add a "Calibrate" API command for an SPL meter that takes a parameter with the cal level, e.g. 94.0. The meter will need to be running to calibrate it. The command body would be:
{"command": "Calibrate", "parameters": ["94.0"]}
 
Good sir, that would be awesome!

So the workflow would be:

Start each instance from a command line (script) with separate prefs files.
Call SPL from API
Call SPL->Calibrate
Then call SPL-Logging->Start

And when we're done for the day, manually save and close.

Sound accurate?

Thanks again!

-brian
 
Pretty much. There's an spl-meter endpoint to control the 4 SPL meters and I'll add an spl-logger endpoint for the logger. I'll include spl-logger commands to load and save files, the save command will take two parameters, the filename and an optional note.
 
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