xovaan
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- Joined
- Oct 4, 2021
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Hey everyone!
First, I want to give a big thanks to everyone for helping me get this far-- there's an overwhelming amount of info online for integrating subs into a 2.2 system, both in general knowledge and program interface navigation for testing. The below is what I've learned through the wonderful help of several members, includng CumSum, 3dbinCanada, and Chromatischism. Apolgies if I left someone out-- thank you too!
Because using the MiniDSP and a UMIK-1 is fairly common, there are some guides online to help. However, for a layman like me who is just starting to grasp the overwhelming landscape of audio, often I find myself questioning edge cases and not being able to dig deeply enough to find exactly what I'm looking for. While I have read a lot of material, the documentation for REW is huge. Hopefully the answers in this post help lay groundwork for people to get their system in a place they like, and in addition learn to ask the questions needed once they're comfortable with the context they acquire
As I receive help in getting my room in order, hopefully this thread will act as a quick guide to help people set up their own system as I learn what I'm doing through the help of others and seeing my system get to a place I'm happy with
Goal:
- Put speakers and couch in an optimal spot
- Integrate two subwoofers into the aforementioned two channel setup
- For both above, using REW and the UMIK-1
Room:
- Rectangular: 16.5'x9.5'x8.5' LxWxH, with a 4" divet at the far wall
Equipment:
- MiniDSP SHD + UMIK-1 microphone + REW for testing
- Two 6.5" MAOP 11 drivers in Pensil 11 cabinets as speaker towers
- Two Rythmik L12 subwoofers
- SMSL DA-9 amplifier
- A decent amount of room treatments, with the side panels on curtain rails to adjust as necessary
Pictures of room (and divet on far wall) (WIP):
Steps taken:
- I used a room calculator and my ears to find the best spots for speakers and couch. This involves measuring my room's dimensions and placing things in base-rate known good starting points.
- In one of the room shots above, you can see my couch at 6 feet from the rear wall and the others is in a nearfield position. Each speaker driver center is about 15" from the side walls, flush with the side traps. Not exactly rule of primes, however my room is kind of narrow and I cannot go narrower with the speakers due to my projector screen
Where I'm at with REW and the miniDSP:
- Place the microphone in the listening position at ear height, with the microphone pointed toward where I'll be looking while listening (straight ahead)
- Configure the MiniDSP SHD matrix to have the speakers and subwofoers on the correct channels (where you plug them in the back of the SHD)
- My UMIK-1 came with a calibration file-- I uploaded it into REW for my tests
- I loaded up REW, and using REW's pink noise generator, I adjusted speaker and subwoofer volume to be a good level for the tests. For speakers, I'll select "full range", for subwoofers, I selected "sub cal" for the time being:
For this test, I'm aiming for ~80dB for speakers and subs when tested individually. For when subs and speakers are tested sub+sub, speaker+speaker, and all four at once, I turned down the volume in this pink noise window to aim for ~80dB when the time comes. The -13.00 dBFS is arbitrary as far as I understand it-- you want your amplifier and SHD to read at a -XX.XX dB on the display that gives you the ability to crank it up to a volume you enjoy after tests are done. When I put my amplifier to 50, the SHD to -14, and REW's generator to -15, I get about 80dB
- Now I perform a measurement test. For this, I put down purple 3m tape (delicate surface tape-- avoid other types of masking tape if you can!) in a matrix to mark room ratios and take note of the "best" places I've found for speakers and subs.
- The way I've found decent spots for my speakers and subs is through attempting two methods thus far: sweeping sine wave measurements while moving the speakers and subwoofers, and something called the Mic Measurement Method shown here:
- The MMM above has you hold your mic and pointing it at the height and direction you will be looking while listening while a pink noise from the screenshot above is being generated, and making slow circular motions while recording the average frequency through the REW menus outlined in that video. This is MUCH faster than sweeping waves, however try both and see what works best for you! (the end of the video shows comparisons to other methods too!)
Measurement window:
I muted my left and right speakers so I am only performing this measurement for my subwoofers (and I did the same for my speakers' tests too):
I then checked the levels to make sure they are the volume I wanted, selected "output", and ran a test. Here is what I've done to position my subs. I have a really bad null and no matter what I do, I can't seem to fix it however having two subs and everyone's help means I can at least have them help each other for most of their ranges
For my speakers my measurements are wild, too:
Next, I need to time align the speaker and subs to one another. This ensures they're in phase and they don't cause any weird peaks and nulls when they fire together. This is where I got pretty confused, however with CumSum's help I was able to work through it
To time align, I selected a speaker that I will sync my other speakers and subs to. If I do this correctly, my other speakers will accurately show how much distance between them and my reference speaker there is. Here is a quick guide that I will outline below: https://www.minidsp.com/applications/auto-eq-with-rew/speaker-time-alignment
First, to set my reference speaker (in this example I will sync everything to my left speaker), in my channel matrix I will only run the left speaker:
And in my measurement window, I put my options to be the following:
"Ref output" is my reference speaker. This will remain "L" throughout my testing, with "Output" changing between L sub, R sub, and R speaker. When I run my subs and right speaker, Output will remain "R" and I will run these speakers and subs through my channel matrix's right channels. I do this because I need the chirp from the reference speaker to start as the measurement points for the others. Important to note that I muted the channels so only a single sub and speaker were running during the measurements.
I ran the test relatively loudly, per CumSum's suggestion, >80dB, in order to get things to register correctly. I heard a high pitched chirp followed by my sine sweep. If this registers correctly, I will see some notes in my left side measurement window (with my graph tabs) that will have distances like this:
My left reference speaker is 0.0867ms, which is below 1ms and works for matching my other speakers. The distances above are actually spot on from where my speakers are in relation to the reference speaker when I use a tape measure to measure the mic to each.
For the above, I wanted to match the timing delay / lag from my other speakers to my furthest speaker/sub, which L Sub. When you lag the speaker timing, it will match the frequency output, otherwise you'll get weird peaks and nulls. In the above, my subwoofer is 0.9088ms from my left speaker, so I did some math to zero them all in. I suck at math so bear with me and if anyone could check my math that would be amazing:
1. I added L Sub's delay to every other channel and make L Sub's timing in that chart 0ms since it's furthest away
2. My reference speaker is now .9955ms (.0867+.9088)
3. Now, with .9088 added to each channel, I added and subtracted the right speaker and sub to match my reference speaker:
Left Speaker: .0867 + .9088 = .9955ms, my new reference point
Right Speaker: -.0796+.9088-.9955 = .1663ms to add to reach .9955, so -.0796+.9088+.1663 = 1.1547ms total
Left Sub: 0ms
Right Sub: -.2559+.9088-.9955 = .3426ms to reach .9955, so 1.2514ms total
Final measurements I need to add to the SHD outputs:
L Speaker: .9955ms
R Speaker: 1.1547ms
L Sub: 0ms
R Sub: 1.2514ms
Now I changed "Timing" in the measurement window to "no timing reference" and put my channel matrix back to the regular outputs and my measurement sweep from 0 to 300, then ran my left speaker, right speaker, and to see if anything is wonky. If I am timed correctly, the sum of my L+R speaker measurements should be roughly the highest points of my left and right speaker measurements throughout:
I then applied a high pass filter to my speakers at the 80hz / 24dB per octave mark, and did the same with a low pass filter for my subwoofers:
And when I ran everything together, everything looks to be in order:
Where I am at now and what I need help with:
Things sound pretty good after running these timing delays and speaker/sub positions through Dirac Live for my final EQ, however:
1. I'm not sure if I'm missing any crucial steps above?
2. I'm not sure what to do about these wonky and quite large nulls, especially given my space restrictions. I've tried a lot of different couch and speaker placements and tried moving my panels around and nothing helps these very large nulls
First, I want to give a big thanks to everyone for helping me get this far-- there's an overwhelming amount of info online for integrating subs into a 2.2 system, both in general knowledge and program interface navigation for testing. The below is what I've learned through the wonderful help of several members, includng CumSum, 3dbinCanada, and Chromatischism. Apolgies if I left someone out-- thank you too!
Because using the MiniDSP and a UMIK-1 is fairly common, there are some guides online to help. However, for a layman like me who is just starting to grasp the overwhelming landscape of audio, often I find myself questioning edge cases and not being able to dig deeply enough to find exactly what I'm looking for. While I have read a lot of material, the documentation for REW is huge. Hopefully the answers in this post help lay groundwork for people to get their system in a place they like, and in addition learn to ask the questions needed once they're comfortable with the context they acquire
As I receive help in getting my room in order, hopefully this thread will act as a quick guide to help people set up their own system as I learn what I'm doing through the help of others and seeing my system get to a place I'm happy with
Goal:
- Put speakers and couch in an optimal spot
- Integrate two subwoofers into the aforementioned two channel setup
- For both above, using REW and the UMIK-1
Room:
- Rectangular: 16.5'x9.5'x8.5' LxWxH, with a 4" divet at the far wall
Equipment:
- MiniDSP SHD + UMIK-1 microphone + REW for testing
- Two 6.5" MAOP 11 drivers in Pensil 11 cabinets as speaker towers
- Two Rythmik L12 subwoofers
- SMSL DA-9 amplifier
- A decent amount of room treatments, with the side panels on curtain rails to adjust as necessary
Pictures of room (and divet on far wall) (WIP):
Steps taken:
- I used a room calculator and my ears to find the best spots for speakers and couch. This involves measuring my room's dimensions and placing things in base-rate known good starting points.
- In one of the room shots above, you can see my couch at 6 feet from the rear wall and the others is in a nearfield position. Each speaker driver center is about 15" from the side walls, flush with the side traps. Not exactly rule of primes, however my room is kind of narrow and I cannot go narrower with the speakers due to my projector screen
Where I'm at with REW and the miniDSP:
- Place the microphone in the listening position at ear height, with the microphone pointed toward where I'll be looking while listening (straight ahead)
- Configure the MiniDSP SHD matrix to have the speakers and subwofoers on the correct channels (where you plug them in the back of the SHD)
- My UMIK-1 came with a calibration file-- I uploaded it into REW for my tests
- I loaded up REW, and using REW's pink noise generator, I adjusted speaker and subwoofer volume to be a good level for the tests. For speakers, I'll select "full range", for subwoofers, I selected "sub cal" for the time being:
For this test, I'm aiming for ~80dB for speakers and subs when tested individually. For when subs and speakers are tested sub+sub, speaker+speaker, and all four at once, I turned down the volume in this pink noise window to aim for ~80dB when the time comes. The -13.00 dBFS is arbitrary as far as I understand it-- you want your amplifier and SHD to read at a -XX.XX dB on the display that gives you the ability to crank it up to a volume you enjoy after tests are done. When I put my amplifier to 50, the SHD to -14, and REW's generator to -15, I get about 80dB
- Now I perform a measurement test. For this, I put down purple 3m tape (delicate surface tape-- avoid other types of masking tape if you can!) in a matrix to mark room ratios and take note of the "best" places I've found for speakers and subs.
- The way I've found decent spots for my speakers and subs is through attempting two methods thus far: sweeping sine wave measurements while moving the speakers and subwoofers, and something called the Mic Measurement Method shown here:
Measurement window:
I muted my left and right speakers so I am only performing this measurement for my subwoofers (and I did the same for my speakers' tests too):
I then checked the levels to make sure they are the volume I wanted, selected "output", and ran a test. Here is what I've done to position my subs. I have a really bad null and no matter what I do, I can't seem to fix it however having two subs and everyone's help means I can at least have them help each other for most of their ranges
For my speakers my measurements are wild, too:
Next, I need to time align the speaker and subs to one another. This ensures they're in phase and they don't cause any weird peaks and nulls when they fire together. This is where I got pretty confused, however with CumSum's help I was able to work through it
To time align, I selected a speaker that I will sync my other speakers and subs to. If I do this correctly, my other speakers will accurately show how much distance between them and my reference speaker there is. Here is a quick guide that I will outline below: https://www.minidsp.com/applications/auto-eq-with-rew/speaker-time-alignment
First, to set my reference speaker (in this example I will sync everything to my left speaker), in my channel matrix I will only run the left speaker:
And in my measurement window, I put my options to be the following:
"Ref output" is my reference speaker. This will remain "L" throughout my testing, with "Output" changing between L sub, R sub, and R speaker. When I run my subs and right speaker, Output will remain "R" and I will run these speakers and subs through my channel matrix's right channels. I do this because I need the chirp from the reference speaker to start as the measurement points for the others. Important to note that I muted the channels so only a single sub and speaker were running during the measurements.
I ran the test relatively loudly, per CumSum's suggestion, >80dB, in order to get things to register correctly. I heard a high pitched chirp followed by my sine sweep. If this registers correctly, I will see some notes in my left side measurement window (with my graph tabs) that will have distances like this:
My left reference speaker is 0.0867ms, which is below 1ms and works for matching my other speakers. The distances above are actually spot on from where my speakers are in relation to the reference speaker when I use a tape measure to measure the mic to each.
For the above, I wanted to match the timing delay / lag from my other speakers to my furthest speaker/sub, which L Sub. When you lag the speaker timing, it will match the frequency output, otherwise you'll get weird peaks and nulls. In the above, my subwoofer is 0.9088ms from my left speaker, so I did some math to zero them all in. I suck at math so bear with me and if anyone could check my math that would be amazing:
1. I added L Sub's delay to every other channel and make L Sub's timing in that chart 0ms since it's furthest away
2. My reference speaker is now .9955ms (.0867+.9088)
3. Now, with .9088 added to each channel, I added and subtracted the right speaker and sub to match my reference speaker:
Left Speaker: .0867 + .9088 = .9955ms, my new reference point
Right Speaker: -.0796+.9088-.9955 = .1663ms to add to reach .9955, so -.0796+.9088+.1663 = 1.1547ms total
Left Sub: 0ms
Right Sub: -.2559+.9088-.9955 = .3426ms to reach .9955, so 1.2514ms total
Final measurements I need to add to the SHD outputs:
L Speaker: .9955ms
R Speaker: 1.1547ms
L Sub: 0ms
R Sub: 1.2514ms
Now I changed "Timing" in the measurement window to "no timing reference" and put my channel matrix back to the regular outputs and my measurement sweep from 0 to 300, then ran my left speaker, right speaker, and to see if anything is wonky. If I am timed correctly, the sum of my L+R speaker measurements should be roughly the highest points of my left and right speaker measurements throughout:
I then applied a high pass filter to my speakers at the 80hz / 24dB per octave mark, and did the same with a low pass filter for my subwoofers:
And when I ran everything together, everything looks to be in order:
Where I am at now and what I need help with:
Things sound pretty good after running these timing delays and speaker/sub positions through Dirac Live for my final EQ, however:
1. I'm not sure if I'm missing any crucial steps above?
2. I'm not sure what to do about these wonky and quite large nulls, especially given my space restrictions. I've tried a lot of different couch and speaker placements and tried moving my panels around and nothing helps these very large nulls
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