REW Beta Release REW API beta releases

[HD MOVIE SOURCE]

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Thank you, very useful.

 

[serko70]

Not a bug but report of a proud moment. This guy took measurements at 25 different mic positions with a 9.2.6 Atmos system and the optimization completed without a hiccup:

That's 850 measurements in REW at some point and probably a record. I guess that tells a lot about how robust REW is.

I cannot thank John enough for creating and maintaining such a great tool for free.

 

[Breeman]

Not a bug but report of a proud moment. This guy took measurements at 25 different mic positions with a 9.2.6 Atmos system and the optimization completed without a hiccup:

View attachment 84275

That's 850 measurements in REW at some point and probably a record. I guess that tells a lot about how robust REW is.

I cannot thank John enough for creating and maintaining such a great tool for free.

I concur, John has created a masterpiece with REW. It is a brilliant piece of software with a great mix of features some not even available in commercial tools. We appreciate you John

 

[armagedon]

hello,
as a feature request, is it possible to be able to upload House curve data via API (POST /eq/house-curve-data ?) as is available for frequency responses (/import/frequency-response-data)
thank you.

 

[John Mulcahy]

as a feature request, is it possible to be able to upload House curve data via API (POST /eq/house-curve-data ?) as is available for frequency responses (/import/frequency-response-data)

That would be possible, yes, though it wouldn't survive an REW restart. I'll add it to the to-do list.

 

[armagedon]

thank you for accepting it.

I have another suggestion regarding the spectrogram feature.
Currently, the color bar uses a linear scale, which is already good.
However, it might also be helpful if users could select an alternative scale based on the house curve showing values relative to it.
For example, using a graduated scale based directly on its offset from the house curve—perhaps ranging from 0 to -25 dB relative to the curve (values set through appearance settings).
This approach could make it easier and clearer for users to quickly identify significant deviations and better understand what they should pay attention to in the spectrogram.

 

[John Mulcahy]

Couldn't you do that by importing the house curve as a measurement and setting that measurement as the SPL reference?

 

[armagedon]

I hadn't considered that. I just tested it, and it seems that the spectrogram currently doesn't take this into account.
However, it would indeed be very beneficial if it worked that way.

 

[John Mulcahy]

I don't understand the spectrogram reference. A house curve has no time dependence, why would it make any sense to reference it on a time-frequency plot?

 

[armagedon]

may be it will be better with an example:

this is a curve equalized to a given house curve:

the spectrogram is like this:

all good

this representation only show when is above 75dB, but the house curve is not 75dB flat. this makes difficult to do verification.

now I use the SPL reference the target (moved to 0dB), the curve is like this now:

the problem is the spectrogram still look the same.

I was expecting it to look to something like this:

 

[John Mulcahy]

Yes, I understood what you meant. I don't see how that would be physically meaningful, or what a spectrogram altered in that way would tell you that isn't equally obvious from the frequency response relative to the reference.

 

[armagedon]

Sir,

Currently, the spectrogram scale does not accurately reflect the house curve as intended.

Typically, when using a spectrogram, our goal is to visualize details that might not be clearly visible in the frequency response graph alone. Implementing the proposed adjustment would enable users to customize the spectrogram display to better suit their specific needs.

Of course, you understand this better than I do.

Thank you!

 

[John Mulcahy]

It's an apples-to-oranges comparison. The spectrogram is showing the evolution of energy content over time. With a few rare exceptions (a dirac pulse, for example) the levels in the spectrogram will not be the levels in the overall frequency response. The integrated energy over the whole windowed span (i.e. the frequency response) is not the same as the energy over any small part of that windowed span (the slices of the spectrogram). A house curve, as a reflection of overall energy within the response, would not be a meaningful target to apply to a spectrogram.

 

[armagedon]

Thank you very much for your detailed response.
I completely understand what you're explaining and I agree that spectrograms and frequency response graphs inherently represent data differently. One displaying time-evolving energy versus the other showing integrated overall energy.

My suggestion wasn't meant to directly equate the spectrogram levels to the frequency response levels. Rather, it aims to use the house curve simply as a customizable reference baseline or offset essentially providing an optional relative scale that can help users highlight meaningful variations more intuitively. The goal would not be to transform the spectrogram into a frequency response, but to allow visualization of time-based variations relative to a known baseline curve.

Think of this not as having the spectrogram "match" the absolute magnitudes from frequency response, but rather as offering the ability to clearly visualize how short-term changes vary against a defined preferred reference. This could make it easier to pinpoint elements that are particularly relevant to individual user preferences, room correction targets, or specific analytical tasks.

I appreciate your insights and your patience in clarifying this matter!

 

[majorwong]

Hi,John.
Recently I find a small bug here that when i load a measurement file (calibration-like) into RTA measurement,the super high frequency lower down about 4dB,not a straight line when you re-measure.

Make sure the measurement file was measured without any calibration file，and the SPL will be 100dB，then the error will show up.
It seems that there's no total coincidence inside(not a straight line).In ARTA,nothing wrong.

But,if you load a real calibration file which the SPL would be 0dB or so,the calibrated process will be OK and no issues with it(a completely straight line shows up there).

It's very useful when you want to see the difference in real time comparing the two or more speakers.Pls have a check for this thanks!.

 

[John Mulcahy]

Recently I find a small bug here that when i load a measurement file (calibration-like) into RTA measurement,the super high frequency lower down about 4dB,not a straight line when you re-measure.

I'm not sure what problem your images are trying to show. Please attach the relevant files.

 

[John Mulcahy]

Builds updated today (beta 90) with these changes:

• Added: A Ramped levels measurement mode that allows a series of measurements to be made with level varying between a start and end level
• Added: A stepped sine test to measure THD vs frequency and level, producing a set of THD vs frequency measurements at the specified levels
• Added: Output level can be appended to the measurement name
• Added: Audio Science Review SPL Vertical and SPL Horizontal measurement results can be imported
• Added: The overlay SPL, Predicted SPL and distortion graphs support a 3D view of the currently selected measurements, e.g. to view a polar set as a surface
• Added: Level and Linearity overlay plots for stepped level measurements
• Changed: rta.properties bundle file has entries for the stepped sine dialog
• Changed: When a measurement is set as the SPL reference it is drawn as a straight line at 0 dB SPL
• Changed: Response copies include the distortion data of the source

I'm not sure how useful the 3D views are, but since they are there I have added them to the SPL, Predicted SPL and Distortion overlays to allow groups of measurements to be viewed. That only really makes sense where the measurements form a meaningful surface, such as a set of polar responses or distortion vs frequency at different levels. To make collecting that sort of data easier the ramped levels mode allows a series of sweeps to be made across a range of levels and there is a stepped mode that measures THD vs frequency across a set of levels. I also added support for importing the SPL Horizontal.txt and SPL Vertical.txt response files Amir makes when reviewing speakers at ASR, they can be dragged and dropped onto the REW window. To generate a normalised view set the 0 degree measurement as the SPL reference.

Here is an example SPL Horizontal.txt import:

Here is a set of sweep measurements of a cheap soundcard showing the 3rd harmonic:

Here is a set of stepped measurements (3 PPO) showing the same 3rd harmonic:

 

[majorwong]

I'm not sure what problem your images are trying to show. Please attach the relevant files.

Hi，the file is attached here.That is to say,first measure a speaker's FR in RTA mode,then load the FR file as a calibration file and re-measure in RTA mode to see whether the measurement is a straight flat line,Unfortunately,there's a null in 8kHz and above.Pls have a check about this,thanks.

 

[John Mulcahy]

Works fine for me. Maybe the cal boost limit in the Analysis preferences is a factor for you.

 

[majorwong]

Works fine for me. Maybe the cal boost limit in the Analysis preferences is a factor for you.

View attachment 84447

Yeah,maybe the boost limit need to be lower as for dB Level,but i need to re-check it.Thanks!

 

[John Mulcahy]

Yeah,maybe the boost limit need to be lower as for dB Level,but i need to re-check it.Thanks!

Just to be clear, I am suggesting you try with this option not selected:

 

[majorwong]

Just to be clear, I am suggesting you try with this option not selected:

View attachment 84468

Hi,John,indeed de-select the checkbox yeseterday.I did what you said but nothing happened,maybe I need change a soundcard myself,while my current card is Tascam US4x4.

 

[thebadlt21]

deleted

 

[John Mulcahy]

Hi,John,indeed de-select the checkbox yeseterday.I did what you said but nothing happened,maybe I need change a soundcard myself,while my current card is Tascam US4x4.

Try taking a measurement using periodic noise and without averaging. The microphone should be in a fixed location, e.g. on a tripod.