REW Beta Release REW API beta releases

[user44455555]

Hello
please see video, the time of the slice is often not visible in this mode. It stand in the line of 80 db but the slice do not overlap it

 

[John Mulcahy]

the time of the slice is often not visible in this mode

I'll add the periods figure to the info label at the top right.

 

[FanatNsk]

Hi everyone. Is it possible to add TIM or DIM distortion measurements to the beta version? I’ve only found this test in one program—ARTA—but it’s very clunky and hasn’t been updated in a long time.

 

[dcibel]

DIM?

In REW you can measure inter-modulation using the signal generator and RTA. The signal generator is quite powerful to define a multitone test of your choosing. In the RTA window, I recommend selecting "show distortion" and save the measurement, on REW main window, select the distortion tab, there you can view just the intermodulation and noise with the fundamental tones removed, which is quite useful.

 

[dcibel]

Ok, I found "DIM" in the ARTA manual, but still don't know what the D stands for. I don't think REW's generator will do a square+sine multitone.

 

[FanatNsk]

The Purifi specifications list DIM distortion—specifically DIM30—at various power levels.

The DIM-30 method
The essence of the method lies in the use of a specific measurement signal consisting of two components:a sequence of rectangular pulses with a repetition frequency of f₁ = 3.18 kHz;a harmonic signal with a frequency of f₂ = 15 kHz superimposed on the pulses.
Key parameters:
signal amplitude ratio U₁:U₂ = 4:1;signal rise rate limited by an RC low-pass filter with a cutoff frequency of fLP = 30 kHz.

 

[dcibel]

Interesting, DIM30 appears to come from IEC 60268-3 spec.

DIM 30 and DIM 100 Measurements per IEC 60268-3 with AP2700

Learn about DIM 30 and DIM 100 measurements per IEC 60268-3 using AP2700 for distortion analysis in audio program material. Setup and measurement details.

www.audioprecision.com

 

[FanatNsk]

DIM30 IEC 60268-3.

The DM30 is a very challenging test for devices—especially those with deep feedback and low slew rates—so I’d like to have it available in a tab right next to IMD CCIF.

 

[John Mulcahy]

The DM30 is a very challenging test for devices—especially those with deep feedback and low slew rates—so I’d like to have it available in a tab right next to IMD CCIF.

I'll add DIM30 and DIM100 in the next build.

 

[GrantSlack]

Before I go over to MacOS 27, do we know if REW will still work?

For months Apple has been notifying me with warnings that software written for Intel Mac hardware won't work with OS 27. I don't know where REW sits on that issue.

 

[John Mulcahy]

REW is a universal binary for Intel or ARM. Others have said REW is working fine on macOS 27.

 

[dcibel]

Minor annoyance - On ALL SPL chart, if there is an impedance measurement in my data set, using "align SPL" creates the following error:

This forces me to de-select the impedance measurement(s) and try again. Would it not be more streamlined to avoid the error message and manual process and just align SPL for measurements with SPL, and skip the impedance measurements in the set?

 

[John Mulcahy]

Would it not be more streamlined to avoid the error message and manual process and just align SPL for measurements with SPL

It would, I have fixed that for the next build.

 

[dcibel]

Thank you

 

[pLudio]

If I save a distortion measurement in REW 5.40 beta 135 with the Capture button in the main window a typical PNG file size can be 3.8MB but if I open the PNG in GIMP and just do File -> Overwrite the file shrinks to 104KB with GIMP compression level 9 so the default compression level you are using seems to be way too low and corresponds to GIMP compression level 0. Old PNG files from REW are small so maybe this changed with the Java version.

 

[John Mulcahy]

Old PNG files from REW are small so maybe this changed with the Java version.

Good spot, thanks. The behaviour changed in Java 9. I have fixed it for the next build.

 

[achugh]

Hi @John Mulcahy can you please take a look at https://www.avsforum.com/posts/64633887/ thread and couple of posts after this thread where the MSO (Multi-Sub Optimizer) team has found how Biquad Coefficients need special adjustments for lower frequencies on miniDSP running the stock 96KHz firmware. Can these optimizations be added into REW EQ wizard when generating the miniDSP biquad file?

As you read posts, you can focus on post by the MSO developer i.e. andyc56 user and its posts so you can quickly filter out all the other conversations happening. You will likely need to read about 4-5 pages from this post to get everything the team found and did to come up with a solution. Thank you for taking a look and potentially doing further optimizing REQ EQ for miniDSP.

 

[thothsong]

Very small request: when using Import Sweep Recordings on a 4M sweep with timing ref stimulus file generated by REW, a popup "Import truncated at 92.8 s" appears. Harmless, but IWBNI if it didn't appear.

 

[John Mulcahy]

Very small request: when using Import Sweep Recordings on a 4M sweep with timing ref stimulus file generated by REW, a popup "Import truncated at 92.8 s" appears. Harmless, but IWBNI if it didn't appear.

Fixed in the next build.

 

[thothsong]

Fixed in the next build.

Thanks!

 

[sm52]

John, good afternoon. When REW starts, a message almost always appears that the input has changed or REW cannot access the input with parameters remaining from the last shutdown. There is a checkbox in the View menu to disable this message. If you check it, the message will not appear only when REW starts? In this REW session, when you call up the measurement window, will it appear if it is required? Can this message be transferred only to the case when the measurement window is called and the previous input settings have been changed?

 

[John Mulcahy]

In this REW session, when you call up the measurement window, will it appear if it is required?

Not if the option to suppress it has been selected, but I'll make a change to display it if there's an attempt to start capture.

 

[mattclarkdotnet]

@John Mulcahy is it intentional that the API requires a pro license for sweeps? It's not mentioned in the Pro upgrade descriptions.

 

[John Mulcahy]

@John Mulcahy is it intentional that the API requires a pro license for sweeps? It's not mentioned in the Pro upgrade descriptions.

Yes, it's intentional. That feature is widely used by companies for production test. It isn't mentioned in the Pro upgrade text yet as the API is only in the beta version, but it's in the API help:

All API GET methods are available whenever the API is running, allowing the API to be used to retrieve data from REW. PUT and POST are also supported by default for most endpoints, but to control REW via the API to make automated sweep measurements requires a Pro upgrade license.