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Open Sound Meter RTA/Phase/A Bunch of Other Program
I know @dumdum on here talks about using Smaart all of the time to see the phase and other cool and neat things. I also know some industry people use Smaart.
This seems like a cool free program that does quite a bit of the same:
https://opensoundmeter.com/
https://user-images.githubuserconten...ddda21efb8.png
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Re: Open Sound Meter RTA/Phase/ETC Program
It does indeed, I did look at it, it’s a bit clunky vs the demo version of smaart, you still need an xlr mic and interface with loop back facility, but free is always good!
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
dumdum
It does indeed, I did look at it, it’s a bit clunky vs the demo version of smaart, you still need an xlr mic and interface with loop back facility, but free is always good!
Nice! I am looking at a cheap option for macbook (and I've heard Asio4All on windows can do it too) of a simple cheap loopback device and a usb microphone. I will be testing this stuff this weekend and see how accurate it is between open sound meter and smaart di v2 (I finally purchased my own copy of it) and this method compared to using a motu m4 and xlr microphone.
In macbooks, you can go to the audio midi app and create a new "aggregate device" which can combine multiple devices to be seen as a single device as well as correct for clock drift. So far it seems to work, I can get all of the data this way (phase, magnitude, coherence, etc), but haven't had time to compare anything further.
The parts I am using for this "cheap" version:
External usb sound card: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
Headphone Splitter (I don't have this one, but any will work): https://smile.amazon.com/Headphone-S.../dp/B07431YDWM
2x Aux Cables
Dayton USB microphone
1) I plug the USB external sound card in and the usb microphone in.
2) I created an aggregate device combing these two items in audio midi.
3) I connected the headphone splitter to the usb sound card out. I then split that signal, using the 2 aux cables, with one going to the amp/dsp and one going to the usb sound card in.
3) In Smaart I set the device to my aggregate device.
4) I select output to the external sound card in the signal generator.
5) I set my measurement to the microphone and reference to the sound card mic in.
This allows me to see phase and all other measurements.
So in reality, if this does give good results, someone could get into this for about $15 more in cost for cheap sound card and headphone splitter with this free program instead of $900 ($600 for smaart di v2, $150-$230 for interface, $60 for cheapest dayton emm-6 xlr microphone)
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Re: Open Sound Meter RTA/Phase/ETC Program
Here is some more on aggregate devices in both windows and mac and very basics on how to make them:
https://www.sweetwater.com/sweetcare...or-pc-and-mac/
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
Jdunk54nl
Nice! I am looking at a cheap option for macbook (and I've heard Asio4All on windows can do it too) of a simple cheap loopback device and a usb microphone. I will be testing this stuff this weekend and see how accurate it is between open sound meter and smaart di v2 (I finally purchased my own copy of it) and this method compared to using a motu m4 and xlr microphone.
In macbooks, you can go to the audio midi app and create a new "aggregate device" which can combine multiple devices to be seen as a single device as well as correct for clock drift. So far it seems to work, I can get all of the data this way (phase, magnitude, coherence, etc), but haven't had time to compare anything further.
The parts I am using for this "cheap" version:
External usb sound card:
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
Headphone Splitter (I don't have this one, but any will work):
https://smile.amazon.com/Headphone-S.../dp/B07431YDWM
2x Aux Cables
Dayton USB microphone
1) I plug the USB external sound card in and the usb microphone in.
2) I created an aggregate device combing these two items in audio midi.
3) I connected the headphone splitter to the usb sound card out. I then split that signal, using the 2 aux cables, with one going to the amp/dsp and one going to the usb sound card in.
3) In Smaart I set the device to my aggregate device.
4) I select output to the external sound card in the signal generator.
5) I set my measurement to the microphone and reference to the sound card mic in.
This allows me to see phase and all other measurements.
So in reality, if this does give good results, someone could get into this for about $15 more in cost for cheap sound card and headphone splitter with this free program instead of $900 ($600 for smaart di v2, $150-$230 for interface, $60 for cheapest dayton emm-6 xlr microphone)
curious... but not convinced as even minute clock differences between the two devices could cause grief, as umik-1 have had issues in the past with timing measurements
for me a Dayton xlr mic and a Behringer 1.5 channel (can’t recall the model no. But it had an xlr input and also a 1/4” Jack input also, plus 1/4” outputs too) it was mucho cheap!
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Re: Open Sound Meter RTA/Phase/ETC Program
Ya. that is why I am interested to test. I have all of those things laying around from measuring impulse response of head units, so I thought they may work for this. I know my macbook has drift correction..not sure how well it will work. I will hopefully find time either tomorrow night or over the weekend to test this. I need to EQ my desktop speakers finally so this will be a great time to test all of this stuff.
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4 Attachment(s)
Re: Open Sound Meter RTA/Phase/ETC Program
Played with this today. Seems to be pretty decent results. Definitely some clock drift issues above like 8k with the usb loopback, so using above that may get difficult.
This is what I am using:
Single I/O device setup:
Motu M4
Dayton Emm-6 microphone
USB devices:
Dayton Umm-6 microphone
External USB sound card
Headphone Splitter
Setup:
Attachment 15206Attachment 15207
Note: These are without any microphone calibration files.
Smaart Results
Attachment 15203
Open Sound Meter Results: Was actually really easy to use, probably took less time to setup compared to Smaart.
Attachment 15210
Moral of this story...For $15 and open sound meter, you can get some decent results, especially below 8k. Above 8k, and you have clock drift issues. You could see the results kept changing every time the clock was adjusted. So if you want to use it above that, you'll need to invest more money.
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Re: Open Sound Meter RTA/Phase/ETC Program
This was really fun to see today Jdunk.
That program is really impressive!
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Re: Open Sound Meter RTA/Phase/ETC Program
Here are some final thoughts after playing some more with Open Sound Meter vs. Smaart. I have been playing with smaart only for a little bit (The demo then I purchased my own copy recently).
Initial measurement setup -> Open Sound Meter was easier
Changing setups -> Smaart is easier
Setting up and Measuring again -> Smaart is easier (it remembers and you can easily create pairs to switch)
Saving -> Smaart auto saves everything and recalls everything upon opening, Open sound meter doesn't even warn you before you exit....ask me how I know.
Overall Open sound meter works well enough if you are just tuning one thing and then putting everything away. It will take overall more time because you have to change all of the settings every time you open it. It doesn't remember if you unplug something. It does seem to remember if everything is ALWAYS plugged in. Like close it on accident and re-open without changing anything it will remember. Smaart just remembers all of your stuff everytime. I created a m4 and a usb sound card setting and switch between the two instantly when I was taking those measurements. Smaart always remembers your settings, probably that autosave everything.
Smaart has a lot of keyboard shortcuts that makes things super quick to measure.
So overall, I can definitely recommend open sound meter and if you aren't using it (even with a usb microphone and a cheap loopback device) you are missing out on very valuable information.
If you are going to be measuring a lot of different things, I would at least get a XLR microphone and something like a motu m2 or focusrite 2i2 and use open sound meter. I would even suggest purchasing Smaart di 2, it will save you a bunch of time. I will be using it when I teach waves and my wife is also a theatre teacher so will be showing her how to use it and her tech students for their shows. Smaart was worth the purchase for me for that stuff.
If you are just starting out in tuning, invest in a XLR measurment microphone like the dayton Emm6 and a device to interface with your computer. It might cost a little more upfront but so worth it compared to a usb microphone since you can use open sound meter with that and get useable results all the way up to 20 khz.
Dayton Emm-6
Focusrite 2i2 3rd gen refurb
Focusrite 2i2 2nd gen
Motu M2
Motu M4
A combination of the Dayton Mic and one of those interfaces would range anywhere from about $160-$300.
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Re: Open Sound Meter RTA/Phase/ETC Program
I was reading over the weekend the Focusrite Scarlet 4i4 has built-in loop-back, so you should be able to do impulse measurements without rigging up a cable and losing an input channel.
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
BigAl205
I was reading over the weekend the Focusrite Scarlet 4i4 has built-in loop-back, so you should be able to do impulse measurements without rigging up a cable and losing an input channel.
The motu m4 apparently has it too. I didn’t have the option on my
macbook (running latest os) with driver installed. Justin had the option on his windows computer but I don’t think he could get it to work.
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Re: Open Sound Meter RTA/Phase/ETC Program
I've just been messing with this.
Some things that I can't see how to do, though:
1. Even setting long buffers, high FFT powers etc, I get quite a bit of variety between measurements. And of course, surely we need to be able to measure several spots. I'd like to be able to average 3 or 4 as per REW. Is that possible?
2. For aligning drivers/crossovers, I guess I can change and watch realtime, but a way of summing measurements and changing level/time delay would be useful? Or is the workflow with this tool just to do it all real time?
Seems like it might be a useful final validation or tune of the odd 1/100th or 10th of a ms. But I don't see how I can do what I can with REW?
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Re: Open Sound Meter RTA/Phase/ETC Program
Definitely need more options added to be comparable especially in the RTA portion. Phase seems to work decent and measurements were very comparable to Smaart.
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
PurpleBass
I've just been messing with this.
Some things that I can't see how to do, though:
1. Even setting long buffers, high FFT powers etc, I get quite a bit of variety between measurements. And of course, surely we need to be able to measure several spots. I'd like to be able to average 3 or 4 as per REW. Is that possible?
2. For aligning drivers/crossovers, I guess I can change and watch realtime, but a way of summing measurements and changing level/time delay would be useful? Or is the workflow with this tool just to do it all real time?
Seems like it might be a useful final validation or tune of the odd 1/100th or 10th of a ms. But I don't see how I can do what I can with REW?
Programs like this are real time measurements programs, that is their benefit. It shows you EVERYTHING REW shows you when you do a sweep (REW RTA doesn't have nearly this info) in real time. You get to see all of that information change in real time compared to REW where you would have to do a sweep, make a change, do another sweep and see if it worked. This isn't just about EQ'ing. That is only a small part of the whole tuning process but what people spend the most time on.
Rew still has some advantages for taking a measurement than applying EQ in their EQ window. In reality though, Open sound meter isn't made for the home or car users, this is made for a professional that is setting up for a concert, a play, etc. They aren't worried about it being "perfect" and do not get a lot of time to do these things. So it needs to be quick and in real time.
Now this is another tool in your toolbox if you have a way of doing a loopback. If you don't have a loopback, this program would be pointless. Preferably some audio interface device like the ones mentioned previously for the best results.
A lot of your questions are answered in the quick start guide: https://opensoundmeter.com/support
1) You can average up to 100 measurements (Like REW's RTA averaging only with ALL of the info) - Change measurement to FIFO instead of LPF. FFT power determines how much power you are willing to devote to the program via your computer. It just does more calculations with higher power, so there should be some minor changes in your measurements.
2) The newest version 3.1 has vector averaging of stored results now. Time delay is the phase graph, this is 10000000000x more accurate than any other way to align drivers. Changing levels is super simple but done in real time. Click the measurement icon and adjust the gain appropriately or better yet, use your dsp to do this.
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Re: Open Sound Meter RTA/Phase/ETC Program
I have an ECM999 mic and an old Edirol USB sound card. I did use one input as a loopback (headphone O/P of the amp, actually) and the mic into the other. It was working as it should and clearly giving valid measurements. I was just doing at my desk with my near field setup - I didn't bother to go out to the car.
I did realise after posting that the "math source" can combine measurements - which was the main missing piece. FIFO averaging gives a long time average, but moving the mic removes HF measurements, presumably because the phase is changing so much. So vector averaging solves this. Also, I agree that being able to sum drivers and time shift to get x-over phase right is better than REW, with its timing reference method.
Still, not being able to model EQ is a big one - and EQ is critically important. Crossover phase and points are largely correct or incorrect - but EQ is subjective. I would not want to start from zero adjusting in real time with pink noise playing.
It does look like a good tool - and could well be my go to for crossover setting. But I guess partly I am just too happy with REW for a lot of the other workflow, plus it does do stuff that I think this can't and never will - export of averaged responses as a .WAV IR, to use in DRC, for example.
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1 Attachment(s)
Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
PurpleBass
I have an ECM999 mic and an old Edirol USB sound card. I did use one input as a loopback (headphone O/P of the amp, actually) and the mic into the other. It was working as it should and clearly giving valid measurements. I was just doing at my desk with my near field setup - I didn't bother to go out to the car.
I did realise after posting that the "math source" can combine measurements - which was the main missing piece. FIFO averaging gives a long time average, but moving the mic removes HF measurements, presumably because the phase is changing so much. So vector averaging solves this. Also, I agree that being able to sum drivers and time shift to get x-over phase right is better than REW, with its timing reference method.
Still, not being able to model EQ is a big one - and EQ is critically important. Crossover phase and points are largely correct or incorrect - but EQ is subjective. I would not want to start from zero adjusting in real time with pink noise playing.
It does look like a good tool - and could well be my go to for crossover setting. But I guess partly I am just too happy with REW for a lot of the other workflow, plus it does do stuff that I think this can't and never will - export of averaged responses as a .WAV IR, to use in DRC, for example.
You can export measurements as osm, cal, txt, or frd.
If you can loop back your dsp into your computer, you can model eq very nicely in this much like you can with smaart.
This is from Nathan Lively, he has a lot of videos on using Smaart
How to set it up
https://www.youtube.com/watch?v=QwOaqTKvFuk
How to do it:
https://www.youtube.com/watch?v=8bi_oZVIJmE
https://youtu.be/ub7gRvhAUEM
Also, moving the microphone is always going to impact HF way more than low, you are greatly changing the measurements in the HF by moving it even mere cm right/left/up/down.
This could also be because on your magnitude graph you are using coherence. If Open sound meter doesn't have a good coherence (how reliable are your measurements) then it won't show those. So click on the magnitude graph and uncheck the "use coherence" check mark. You can also switch one of the three graphs to coherence and see how reliable your measurments are. If it isn't close to 100% across the board, you need to turn up the volume or turn down whatever is causing bad coherence in the room.
I had terrible coherence in the HF when I was using the usb microphone and external usb soundcard for loopback due to clockdrift. It wouldn't show any of the HF data unless I turned off "use coherence"
Attachment 15238
Edit* Video on how to get good coherence
https://youtu.be/S_A1BVOqNXM?t=312
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3 Attachment(s)
Re: Open Sound Meter RTA/Phase/ETC Program
I made these because I was talking to the creator of Open Sound Meter and wanted to better explain the two setups:
Setup 1: Motu and XLR mic
Attachment 15239
Setup 2: USB Loopback and USB microphone:
Attachment 15241
Attachment 15240
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Re: Open Sound Meter RTA/Phase/ETC Program
New version of Open Sound Meter was just released by Pavel (creator of it)
https://opensoundmeter.com/download
v0.3.1 is out
In this update:
- fixes for MOTU drivers on macOS
- fix for calibration files (If you already have calibration file created with the software, you need to recreate it)
- Spectrogram now has options for colours thresholds
- Math source has an option of operation type: polar or vector
- Auto notes for stores includes info about applied gain and selected device
- Data import supports CSV format
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Re: Open Sound Meter RTA/Phase/ETC Program
Anyone else try it out yet? Post your thoughts/results after using it!
It really is a game changer to be able to measure phase in real time! You can do fun things with this to get it to align the best possible.
I was eq'ing some speakers I built (PE C notes as can be seen here) and a sub.
This was the best I could get at first:
Note: These are Smaart pictures but open sound meter does the same thing.
You can see in the middle the real time phase. The orange is the sub, the green and pink are each speaker individually and the blue is both speakers. Everything was lined up the best I could get it by just introducing time delays. This is what I would normally just do in REW and get it the best possible after HOURS of work in sweeps and small adjustments. This was after spending countless hours trying to figure out how to get REW to properly measure phase that was useable. It is not the easiest process.
https://www.audiosciencereview.com/f...s-jpeg.123211/
I would have never thought of doing this if I hadn't seen the phase in real time (and thanks to @dumdum for the suggestion, but he wouldn't have been able to suggest this without seeing the phase picture either).
The picture below, I flipped the polarity of the sub because this aligned the slope of the phase better, and then used time delay to get them to line up. The next step would be all pass filters, but this wasn't needed after doing the polarity flip. You can see, the sub phase, left speaker phase, and right speaker phase are all locked on to each other VERY well.
This is how you properly integrate subs with mains.
This also took me like an hour or so to learn to use the program and about an hours worth of time to do this. In REW, this would have been at minimum a few hours probably over the course of a few days to get not even close to this. There is no more guesswork here. This is about the best it is ever going to get.
https://www.audiosciencereview.com/f...ty-jpg.123213/
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Re: Open Sound Meter RTA/Phase/ETC Program
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Re: Open Sound Meter RTA/Phase/ETC Program
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
Jdunk54nl
Anyone else try it out yet? Post your thoughts/results after using it!
It really is a game changer to be able to measure phase in real time! You can do fun things with this to get it to align the best possible.
I was eq'ing some speakers I built (PE C notes as can be seen here) and a sub.
This was the best I could get at first:
Note: These are Smaart pictures but open sound meter does the same thing.
You can see in the middle the real time phase. The orange is the sub, the green and pink are each speaker individually and the blue is both speakers. Everything was lined up the best I could get it by just introducing time delays. This is what I would normally just do in REW and get it the best possible after HOURS of work in sweeps and small adjustments. This was after spending countless hours trying to figure out how to get REW to properly measure phase that was useable. It is not the easiest process.
https://www.audiosciencereview.com/f...s-jpeg.123211/
I would have never thought of doing this if I hadn't seen the phase in real time (and thanks to @dumdum for the suggestion, but he wouldn't have been able to suggest this without seeing the phase picture either).
The picture below, I flipped the polarity of the sub because this aligned the slope of the phase better, and then used time delay to get them to line up. The next step would be all pass filters, but this wasn't needed after doing the polarity flip. You can see, the sub phase, left speaker phase, and right speaker phase are all locked on to each other VERY well.
This is how you properly integrate subs with mains.
This also took me like an hour or so to learn to use the program and about an hours worth of time to do this. In REW, this would have been at minimum a few hours probably over the course of a few days to get not even close to this. There is no more guesswork here. This is about the best it is ever going to get.
https://www.audiosciencereview.com/f...ty-jpg.123213/
out of interest where the timings off to the tape measure with the flipping of the phase on the sub, I have tried to help the odd person, but one disagreed and insisted I prove it to him as he didn’t believe there could be two ways to time a sub and both would work...
I always start with a tape, but often find swapping phase and adjusting the ta to bring it back in time works better than the tape and normal phase
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Re: Open Sound Meter RTA/Phase/ETC Program
I did that with the last iteration of my tuning. I didn't measure phase and flipped the midbass, which gave me much better and more even summation at both ends of the driver to the sub and tweeters.
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Re: Open Sound Meter RTA/Phase/ETC Program
I'm going to try and learn how to use this tool. I have a UMIK-1, Audiofrog UMI soundcard (came with the microphone) and I just ordered an aux splitter. I do have a couple of questions:
1. When I do the measurements, should I just place the UMIK in the headrest and stand outside the car?
2. Do I need to configure the UMIK cal file anywhere like I do with REW?
3. Can I just connect the output AUX to my OEM Aux In instead of the DSP?
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
swrocket
I'm going to try and learn how to use this tool. I have a UMIK-1, Audiofrog UMI soundcard (came with the microphone) and I just ordered an aux splitter. I do have a couple of questions:
1. When I do the measurements, should I just place the UMIK in the headrest and stand outside the car?
2. Do I need to configure the UMIK cal file anywhere like I do with REW?
3. Can I just connect the output AUX to my OEM Aux In instead of the DSP?
1. When I do the measurements, should I just place the UMIK in the headrest and stand outside the car?
Definitely keep the microphone in a single position the ENTIRE time. Where you are doesn't really matter, just don't interfere with the microphone (so don't just be holding it right in front of you).
2. Do I need to configure the UMIK cal file anywhere like I do with REW?
You can and if you go to open sound meter and read the manual it shows you how I believe. In reality, it doesn't seem to make that much of a difference in my small window of testing.
3. Can I just connect the output AUX to my OEM Aux In instead of the DSP
Yes, you want the output from your laptop going through EVERYTHING in your system, that way the ultimate signal delay is accounted for and any oddities within your HU.
I also posted this up a little bit, but read this and watch the videos. This applies to all speaker pairs even though they are working on the Sub - Midbass alignment. That one just proves to be one of the hardest due to the wavelengths of sub frequencies.
https://www.merlijnvanveen.nl/en/stu...bsolute-method
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Re: Open Sound Meter RTA/Phase/ETC Program
I have used OSM a little while ago for phase and it is brilliant. I tried at the weekend using it for frequency EQing, and I could not get consistent results. I was ripping my hair out...
I might have been slow to realise this, but it also might be useful to point out to others - *your usual target curves do not apply to the Magnitude plot*. This is because, of course, magnitude is the difference between electrical input to your sound card (loopback) and acoustic input (measurement mic). Normally, you measure with pink noise - and that is the same here. Pink noise "rolls off" at 3db per octave, so if you EQ "flat" you are actually EQing a 3db/Oct roll off. Now, because it's the difference we're looking at, that 3db roll off is on both the loopback and mic signals - and is therefore "removed". So if you want a +5db/oct rise down from 160Hz (Harman) that is actually a +2db rise... If you want it flat from 160-2k, that is actually a 3db/oct rise, etc.
This is for sure possible to work around - you could easily create compensated target curves. But overall I just don't see the benefit over REW RTA, and it's integrated EQ simulation etc. OSM is great for phase, and using the magnitude plot to get maximum summing a crossover frequency when using all-pass or tweaking delay. But for me isn't a one-stop-shop.
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
PurpleBass
I have used OSM a little while ago for phase and it is brilliant. I tried at the weekend using it for frequency EQing, and I could not get consistent results. I was ripping my hair out...
I might have been slow to realise this, but it also might be useful to point out to others - *your usual target curves do not apply to the Magnitude plot*. This is because, of course, magnitude is the difference between electrical input to your sound card (loopback) and acoustic input (measurement mic). Normally, you measure with pink noise - and that is the same here. Pink noise "rolls off" at 3db per octave, so if you EQ "flat" you are actually EQing a 3db/Oct roll off. Now, because it's the difference we're looking at, that 3db roll off is on both the loopback and mic signals - and is therefore "removed". So if you want a +5db/oct rise down from 160Hz (Harman) that is actually a +2db rise... If you want it flat from 160-2k, that is actually a 3db/oct rise, etc.
This is for sure possible to work around - you could easily create compensated target curves. But overall I just don't see the benefit over REW RTA, and it's integrated EQ simulation etc. OSM is great for phase, and using the magnitude plot to get maximum summing a crossover frequency when using all-pass or tweaking delay. But for me isn't a one-stop-shop.
That isn’t accurate... you eq with pink noise with rew so rew will also have the same lowering of level by default that you describe... magnitude is fine to use to set up eq, I frequently do this on smaart with below 400hz
thats because pink noise is how we hear and is made to be the correct level, white noise is recorded flat from 20-20khz
it also won’t be why you couldn’t get consistent results as it’s definitely consistent... it is equal and so consistency is down to measurement techniques not the software or signal input
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
dumdum
That isn’t accurate... you eq with pink noise with rew so rew will also have the same lowering of level by default that you describe... magnitude is fine to use to set up eq, I frequently do this on smaart with below 400hz
thats because pink noise is how we hear and is made to be the correct level, white noise is recorded flat from 20-20khz
it also won’t be why you couldn’t get consistent results as it’s definitely consistent... it is equal and so consistency is down to measurement techniques not the software or signal input
I appreciate that we want to use pink noise because that is how we hear, and that REW RTA showing "flat" will have a -3db roll off in terms of power.
As for OSM, if I turn up the signal going into the sound card, the audio level rises but so does the loopback level. So the magnitude stays the same. If the output level is raised in a non-linear way (e.g., using white noise not pink) magnitude still stays the same, because the amplitude of each frequency has risen on both loopback and acoustic inputs.
I can say, that keeping everything the same, taking a measurement in REW and then in OSM, importing the OSM magnitude measurement into REW and level matching, they were not close to the same. Measuring was consistent. The displayed FR was not consistent. I can make multiple measurements in REW and they are consistent with themselves. I can make multiple measurements in OSM and they are consistent with themselves. I can use sweeps or RTA in REW, and they are consistent with each other (with a db or so more HF roll off from a sweep - but I guess this is how it responds to reflections and comb filtering). But OSM magnitude is way lower in the bass and higher in the treble, compared with REW.
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Re: Open Sound Meter RTA/Phase/ETC Program
The magnitude aspect should definitely work for tuning....Yes, you need to set levels between your microphone and loopback appropriately to use it. But if you get a flat line across the magnitude then you have a flat response (according to pink noise if you are using that). It is telling you the difference between what pink noise is on the loopback and what your microphone is measuring. If you don't believe me, switch one of the graphs to RTA mode and you get RTA measurements just like in REW. Flat on RTA will be a flat line on magnitude (when using pink noise). The magnitude will just show the level according to the loopback and RTA will be an "absolute" level.
Saying that, I still like REW for EQ. I like to take my measurements in REW, go back inside the house, sit in a comfy chair, and use it's EQ panel for crossover and filters. Then go back out, input that stuff, remeasure, adjust where needed then be done with EQ and finally open smaart (or open sound meter) and check phase relationships and adjust appropriately.
How to measure and EQ (In smaart but same principle)
https://www.youtube.com/watch?v=ub7gRvhAUEM
Resource Guide: How do I EQ my Speakers?
https://www.youtube.com/watch?v=93pHuHLZuPc
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Re: Open Sound Meter RTA/Phase/A Bunch of Other Program
I would eventually like to try this out. Can you go over the details about how I need to do this with a USB mic? I think you mentioned some piece of software that is needed somewhere in order to make this work with a USB mic? I'll have to go back through the thread.
I'm very familiar with REW, but mainly for pink-noise RTA measurements. I've take sweeps a few times, but it was a major PITA, to be honest - I would MUCH rather be able to measure "live" phase instead of trying to use sweeps.
I'm just looking for an idea of what I need hardware and software-wise - in order to use this app with a USB MIC successfully. Or would you recommend an XLR MIC instead? If that makes it easier, I don't mind spending the money if the USB mic method is "hack'ish".
Thanks!
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Re: Open Sound Meter RTA/Phase/A Bunch of Other Program
Quote:
Originally Posted by
jtrosky
I would eventually like to try this out. Can you go over the details about how I need to do this with a USB mic? I think you mentioned some piece of software that is needed somewhere in order to make this work with a USB mic? I'll have to go back through the thread.
I'm very familiar with REW, but mainly for pink-noise RTA measurements. I've take sweeps a few times, but it was a major PITA, to be honest - I would MUCH rather be able to measure "live" phase instead of trying to use sweeps.
I'm just looking for an idea of what I need hardware and software-wise - in order to use this app with a USB MIC successfully. Or would you recommend an XLR MIC instead? If that makes it easier, I don't mind spending the money if the USB mic method is "hack'ish".
Thanks!
It is posted a couple of times (even with pictures!) about how to do this, at least on a macbook. Windows will need to use asio4all for aggregate devices.
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Re: Open Sound Meter RTA/Phase/A Bunch of Other Program
I'm just trying to understand this a little better from a hardware perspective - for WIndows devices.
I'm not 100% clear on whether it's best to try to make a USB MIC work or just buy an XLR MIC instead. I don't want to go and buy a USB sound card and then realize a week later that I would have been better off if I bought an XLR MIC instead.
It *sounds* like you're better off with an XLR MIC - someone also mentioned something about a "Behringer 1.5 channel" something or other along with the XLR MIC.
Again, I just want to understand my options a little better *before* I purchase anything.
So I'm looking for opinions on the best XLR mic and whatever other equipment I'd need for the XLR MIC if I go that route (assuming that I really am better off with an XLR MIC as opposed to using my UMIK-1 USB MIC).
Thank you.
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Re: Open Sound Meter RTA/Phase/ETC Program
100% buy an xlr microphone and xlr microphone interface if you can. Hands down no questions asked there.
Motu m2 (or m4) or focusrite 2i2 (or 4i4) are great options with a dayton emm-6 microphone.
However, interfaces currently are hard to find due to chip shortages.
With that, most people with a usb microphone don't actually need to buy anything. They can use asio4all to make an aggregate device with an internal loopback (google this) and can then use the usb microphone they already have and get pretty decent results. Or a $5 usb sound card and headphone splitter and a aggregate loopback using that.
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
Jdunk54nl
100% buy an xlr microphone and xlr microphone interface if you can. Hands down no questions asked there.
Motu m2 (or m4) or focusrite 2i2 (or 4i4) are great options with a dayton emm-6 microphone.
However, interfaces currently are hard to find due to chip shortages.
With that, most people with a usb microphone don't actually need to buy anything. They can use asio4all to make an aggregate device with an internal loopback (google this) and can then use the usb microphone they already have and get pretty decent results. Or a $5 usb sound card and headphone splitter and a aggregate loopback using that.
that’s exactly what I started with... the Behringer interfaces are cheap and ok... but the focusrite (I have a 2i2) are very much superior and you won’t need to upgrade for many years... For not too much more cash... and a Dayton mic is also good, I’d play with a Dayton for a start, I see a mic as an essential piece of kit and when I’m setting up an ultra, a z150.6ap and a few grands worth of drivers I didn’t think a cheap pro level mic at £220 and a £130 interface was too bad
dont forget to aim the mic up and forwards not forwards! The angle of incidence of both drivers to the mic needs to be the same and a right angle to mids and tweeters with the mic tip at the middle of the ears is the only place that they will read the same response and phase
think about a tweeter where the polar response changes as you come off axis from it... this is also evidenced by the polar response diagrams for the higher end mics, even with a 1/4 tip mic (isemcon or earthworks for example) it makes a small difference, and with a mic like the Dayton it is a 1/2” tip (Dayton/umik-1)!with a bigger capsule than a 1/4” so it compounds the error
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
dumdum
that’s exactly what I started with... the Behringer interfaces are cheap and ok... but the focusrite (I have a 2i2) are very much superior and you won’t need to upgrade for many years... For not too much more cash... and a Dayton mic is also good, I’d play with a Dayton for a start, I see a mic as an essential piece of kit and when I’m setting up an ultra, a z150.6ap and a few grands worth of drivers I didn’t think a cheap pro level mic at £220 and a £130 interface was too bad
dont forget to aim the mic up and forwards not forwards! The angle of incidence of both drivers to the mic needs to be the same and a right angle to mids and tweeters with the mic tip at the middle of the ears is the only place that they will read the same response and phase
think about a tweeter where the polar response changes as you come off axis from it... this is also evidenced by the polar response diagrams for the higher end mics, even with a 1/4 tip mic (isemcon or earthworks for example) it makes a small difference, and with a mic like the Dayton it is a 1/2” tip (Dayton/umik-1)!with a bigger capsule than a 1/4” so it compounds the error
This is interesting as the IASCA RTA test had the mic tip pointing forward towards the windscreen.
Sent from my iPhone using Tapatalk
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
SiW80
This is interesting as the IASCA RTA test had the mic tip pointing forward towards the windscreen.
Sent from my iPhone using Tapatalk
but as long as all cars get measured like that and you set the eq for it it’s fine... however it won’t do a very good job of matching left to right as the right in a rhd with the mic pointing forward at/on the headrest is always more on axis so the top end is emphasised more on one side vs the other
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
dumdum
think about a tweeter where the polar response changes as you come off axis from it... this is also evidenced by the polar response diagrams for the higher end mics, even with a 1/4 tip mic (isemcon or earthworks for example) it makes a small difference, and with a mic like the Dayton it is a 1/2” tip (Dayton/umik-1)!with a bigger capsule than a 1/4” so it compounds the error
Isn't the dayton mic a 6mm capsule so 1/4"? The total area of the tip is bigger for sure on the emm-6 though (probably close to 1/2") if that is what you mean.
https://www.parts-express.com/Dayton...MaAhPvEALw_wcB
From above link:
Specifications: • Capsule type: 6 mm electret condenser • Polar pattern: omni-directional • Frequency response: 18 Hz - 20 kHz • Impedance: 200 ohms between pins 2 and 3 • Sensitivity at 1 kHz into 1K ohm: 10mV/Pa (-40 dBV, re. 0 dB = 1V/Pa) • Max SPL for 1% THD @ 1 kHz: 127 dB • S/N ratio: 70 dB A-weighted • Connector: gold plated XLR • Phantom power: +15V to +48V, 4 mA • Weight: 144 grams.
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Re: Open Sound Meter RTA/Phase/ETC Program
Quote:
Originally Posted by
Jdunk54nl
Isn't the dayton mic a 6mm capsule so 1/4"? The total area of the tip is bigger for sure on the emm-6 though (probably close to 1/2") if that is what you mean.
https://www.parts-express.com/Dayton...MaAhPvEALw_wcB
From above link:
Specifications: • Capsule type: 6 mm electret condenser • Polar pattern: omni-directional • Frequency response: 18 Hz - 20 kHz • Impedance: 200 ohms between pins 2 and 3 • Sensitivity at 1 kHz into 1K ohm: 10mV/Pa (-40 dBV, re. 0 dB = 1V/Pa) • Max SPL for 1% THD @ 1 kHz: 127 dB • S/N ratio: 70 dB A-weighted • Connector: gold plated XLR • Phantom power: +15V to +48V, 4 mA • Weight: 144 grams.
It’s a 6mm capsule, and a 1/2” tip, so my isemcon with a 1/4” tip must be 4mm I presume, so less directional, but even with a 4mm or whatever size capsule it still Varys off axis depending on freq, obv at lower freqs it doesn’t really matter...
if I can find the isemcon document that shows even a fine tipped mics phase and amplitude difference at various angles
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Re: Open Sound Meter RTA/Phase/ETC Program
https://www.isemcon.com/datasheets/EMX7150-US-r04.pdf
it seems to be a marked difference somewhere between 8 and 16khz, but if you double the size of the capsule the freq halves so 4-8lhz would be roughly similar
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Re: Open Sound Meter RTA/Phase/ETC Program
I have the comparison with both Dayton and isemcon mics at the same spot and angle in the corsa, it doesn’t look much, but it varys phase also due to levels being different, and the isemcon is also far more accurate without a calibration file vs my Dayton and umik-1