Venturing in REW + UMIK 1

ankitbhargava

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Covid is giving all opportunities which weren't there in everyday busy life :)

I bought a UMIK 1 and read some basic stuff to venture into REW measurements.
The aim was to measure the accurate output and graphs from system and specially Subs, find out what Audessey MultEQ32 does to my system and if its worth, integrate the 2 differently capable subs in more jovial way, find acoustic issues with my Room and learn some technicalities (if the patience persists for a couple of months).

Please consider me as the learner at very basic stage as far as REW goes, so far I have only made improvements in my HT system relying on my ears.

I would like to open this thread to find out if I am approaching the measurements correctly and then to learn to analyse the result. Probably, make possible changes to system for any improvisations.

This is what I have done so far to take first measurement

1. Downloaded REW version for MacBook (which is still on Catalina)
2. Connected UMIK 1 with the supplied cable for input, connected HDMI cable from Laptop to AVR (aux1) for output
3. Did basic configuration, downloaded and added Calibration file
4. Set the level (which came out about -20.5db) on AVR to play 75db of pink noise using the signal generator (playing at -12.0 dbfs) + SPL meter on REW
5. Took a couple of measurements of Front Left, Front Right, Front L+R and sub woofers (separately and combined)

Please advise if I followed correct steps in measurement :)
I shall be posting the screenshot of graphs as well as the measurement file for anyone keen to help.

Thanks in advance
 

sud98

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Make sure you use the 90deg callibration file and keep the mic at the MLP and point it upwards. Also, to get a clean base value, make sure that AVR is not making any modifications and is in direct mode, you can then compare the same with audyssey on, so you get the comparison.
 

yogibear

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Covid is giving all opportunities which weren't there in everyday busy life :)

I bought a UMIK 1 and read some basic stuff to venture into REW measurements.
The aim was to measure the accurate output and graphs from system and specially Subs, find out what Audessey MultEQ32 does to my system and if its worth, integrate the 2 differently capable subs in more jovial way, find acoustic issues with my Room and learn some technicalities (if the patience persists for a couple of months).

Please consider me as the learner at very basic stage as far as REW goes, so far I have only made improvements in my HT system relying on my ears.

I would like to open this thread to find out if I am approaching the measurements correctly and then to learn to analyse the result. Probably, make possible changes to system for any improvisations.

This is what I have done so far to take first measurement

1. Downloaded REW version for MacBook (which is still on Catalina)
2. Connected UMIK 1 with the supplied cable for input, connected HDMI cable from Laptop to AVR (aux1) for output
3. Did basic configuration, downloaded and added Calibration file
4. Set the level (which came out about -20.5db) on AVR to play 75db of pink noise using the signal generator (playing at -12.0 dbfs) + SPL meter on REW
5. Took a couple of measurements of Front Left, Front Right, Front L+R and sub woofers (separately and combined)

Please advise if I followed correct steps in measurement :)
I shall be posting the screenshot of graphs as well as the measurement file for anyone keen to help.

Thanks in advance

I have been sitting with MiniDSP HD 2X4 and Umik 1 for last many years. I guess I should follow you. Thanks for sharing.

Guess, we are the loners from Rajasthan on the forum. Good to know.
 

ankitbhargava

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Make sure you use the 90deg callibration file and keep the mic at the MLP and point it upwards. Also, to get a clean base value, make sure that AVR is not making any modifications and is in direct mode, you can then compare the same with audyssey on, so you get the comparison.
Thanks, yes followed the exact same process
 

ankitbhargava

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I have been sitting with MiniDSP HD 2X4 and Umik 1 for last many years. I guess I should follow you. Thanks for sharing.

Guess, we are the loners from Rajasthan on the forum. Good to know.
:) lets use this thread to make sure we improvise our systems, its a lot of time and money investment and definitely a fun to learn.
 

ankitbhargava

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Screenshot 2020-09-20 at 8.32.16 PM.png

Screenshot 2020-09-20 at 8.35.50 PM.png

Preparation
Plugged in UMIK 1 to Laptop USB and connected AVR using HDMI cable, ran REW, added calibration (90 degree) file, changed output to HDMI in sound card.

Then the Level matching after basic setup of REW, matched the level by playing Pink Noise using "Signal Generator" and adjusting Master Volume on AVR so that the SPL meter reads "75db" for both the L+R speakers and the Subs (both subs). I found that playing -12dbfs Pink Noise on Signal Generator, the AVR gives "75db" output on L+R around Master Volume (MV) of -27 db approx. Subs level I kept around 78db

+++++++

Step 2
Took the measurement of Subs (both subs together) without Audessey filters (green curve) and then with Audessey Flat Filter (Blue Curve). Here is the curve after smoothing to 1/12 octave.
M_Subs_comp20Sept.jpg


Step 3
Took the measurement of Front Left and Front Right Speakers together (the brown curve)

M_20Sept_Smooth.jpg


Step 3

Look up Decay and Waterfall

Decay_Subs_20Sept.jpg
Decay of Subs
++++++++


Decay_LR_20Sept.jpg
Decay of L+R

++++++

WaterFall_Subs_20Sept.jpg
Waterfall of Subs

+++++

WaterFall_LR_20Sept.jpg
Waterfall of L+R

+++

I haven't been able to conclude much from above but one important aspect that UMIK + REW helped me is to level match all the speakers properly. The supplied Mic with AVR for the Audessey correction is way off the correct measurement.
 

RajithKumar

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Good initiative to start a seperate thread on REW.
Me too a learner...Based on little knowledge .For sub measurements you may need to do in Pure direct mode.Also smoothing should not be applied for it.
Find out best possible location using it .
After that do Audyssey which will give a better results.
The LCR also can be measured to find out best crossover points and also to find out phase issues between subs and Main speakers .
 

ankitbhargava

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Good initiative to start a seperate thread on REW.
Me too a learner...Based on little knowledge .For sub measurements you may need to do in Pure direct mode.Also smoothing should not be applied for it.
Find out best possible location using it .
After that do Audyssey which will give a better results.
The LCR also can be measured to find out best crossover points and also to find out phase issues between subs and Main speakers .
Thanks, yes the one I posted above "without Audessey" is actually on Pure Direct setting.
Unfortunately I don't have much provision to move my Subs :( as I have HT setup in my main Bedroom (my wife cooperates a lot)
Let me post a picture of my front stage.

I did some experiments to realise having Phase 0 on PB 1000 and Phase 90 on PB 2000 Pro gives some extra db between 20-30 Hz frequency. Also the crossover of 100 gives a more flatter curve as against 80.

room4.jpeg
 

sud98

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I think your waterfall settings are incorrect, I will research and check you the right settings. I think the window needs to be around 300 to 500ms.
 

RajithKumar

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Thanks, yes the one I posted above "without Audessey" is actually on Pure Direct setting.
Unfortunately I don't have much provision to move my Subs :( as I have HT setup in my main Bedroom (my wife cooperates a lot)
Let me post a picture of my front stage.

I did some experiments to realise having Phase 0 on PB 1000 and Phase 90 on PB 2000 Pro gives some extra db between 20-30 Hz frequency. Also the crossover of 100 gives a more flatter curve as against 80.

View attachment 49913
Agreed even in dedicated room it's little difficult to move subs around...but however it can be planned and managed.But in Bed room it will be difficult.
Also 100 hz crossover is not a problem unless your both subs are positioned in front.
Otherwise sometimes the bass localisation can happen ( particularly between 80 hz and 100 hz).
Check it once again by adjusting the sub distance ( individually 1 at time ) so that u can able to bring down to 80 hz crossover region.
 

alphacentury100

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Most of us dont have the privilege of moving the sub to any optimal position so you can introduce some delay in the output section of the minidsp, to one of the subwoofer. It helped a lot in getting a flatter curve in my case, while working with more than one sub.
And, never apply smoothening while measuring the subwoofers. The smoothening is usually applied only while measuring the entire (up to 20khz) audio bandwidth.
 

alphacentury100

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Thanks, yes the one I posted above "without Audessey" is actually on Pure Direct setting.
Unfortunately I don't have much provision to move my Subs :( as I have HT setup in my main Bedroom (my wife cooperates a lot)
Let me post a picture of my front stage.

I did some experiments to realise having Phase 0 on PB 1000 and Phase 90 on PB 2000 Pro gives some extra db between 20-30 Hz frequency. Also the crossover of 100 gives a more flatter curve as against 80.

View attachment 49913
Thats one beautiful room you have.
 

ankitbhargava

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Thanks for the link, this is helpful

Reason to set the limits to higher "ms" is there were frequencies which were even 1200 ms decay time (around 36 hz)

I do have Room mode around 30 hz with a spike of 10db+ and to my surprise it helps in making thumps/slaps/door bangs etc more impactful
 

ankitbhargava

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Most of us dont have the privilege of moving the sub to any optimal position so you can introduce some delay in the output section of the minidsp, to one of the subwoofer. It helped a lot in getting a flatter curve in my case, while working with more than one sub.
And, never apply smoothening while measuring the subwoofers. The smoothening is usually applied only while measuring the entire (up to 20khz) audio bandwidth.
Thanks for the pointer, I shall be posting non-smoothened curves.
I haven purchased the Minidsp so far to EQ my Subs but I am considering this investment.
Still trying to understand how much would I benefit.

I have played around with delay after Audessey and even Manual measurement, adding 4feet (equivalent to 4ms) to SVS PB 2000 Pro helped to bring up some dips.
 

ankitbhargava

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Agreed even in dedicated room it's little difficult to move subs around...but however it can be planned and managed.But in Bed room it will be difficult.
Also 100 hz crossover is not a problem unless your both subs are positioned in front.
Otherwise sometimes the bass localisation can happen ( particularly between 80 hz and 100 hz).
Check it once again by adjusting the sub distance ( individually 1 at time ) so that u can able to bring down to 80 hz crossover region.
I have made some adjustments today and now crossover 80 Hz sounds much tighter, somehow there is more tactile response in my go to scenes. :)
 

ankitbhargava

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Some more experiments,
today I gave more attention to the "basic setup" before measurement to fine tune settings I need in my MacBook for correct measurements.
This link was helpful :https://www.avsforum.com/threads/rew-for-macos-how-to-setup-your-mac-for-rew.3075106/

I learnt that this "basic setup" is VERY important, level matching by playing pink noise through REW is also VERY important.

Did a comparative of subwoofers response

Red line is "direct mode"
Green line is "AVR set to 7.1 channel"
**since there was a big dip in 45-55 Hz range, I just added some gain in PB 2000 pro to increase from "-18dbfs" to "-15dbfs"
Purple line is "after the gain applied and still no Audessey filter"
** added "-3db" more to PB 2000 pro
Orange line is after applying the "-3db" more gain to make it "-12dbfs"

All above without Audessey filters.

After this experiment, I played some go to scenes and the bass sounder more fuller, louder and also the LF effects were more impactful.

I frequently refer to scenes from John Wick 3 (john hitting hammer on floor", scene from "Arrival" where they are in Helicopter to take them to Alien site .. the helicopter blade blade rotation sound measures about 112 db and I still look for clarity as against muddy sound. I also refer to Dolby Atmos demo scenes from The Tomb Raider.

Comparison_Audessey_subs.jpg

After above I also applied a PEQ on PB 2000 pro to pump up 50 hz and nearby frequencies (I know I should be more concerned about peaks than nulls) to try to boost the overall db in all frequency range of subs.

Result was even pleasant, I will share that curve toon next post.

Time spent brought me some conclusions
1. Audessey MultQT 32 was degrading the loudness the subs should show in scenes where subs need to hit 115db, though theoretically after applying MultQT 32 ... the FR is flatter but it takes away some fun of those sudden surges to "feel the base" and not only "hear it".
2. I have kind of understood where correctly to set the gain on sub and corresponding to that on AVR
3. Changing Phase of PB 2000 pro from "0" (PB 1000 is also on 0 )" to 90 made the bass more punchier and tight. I could hear that helicopter scene from "Arrival" on netflix .. the rotating blades sounded more tight and high db.
4. Achieving more db on Subs has made decay time and decay rate worst but somehow in real life I don't hear the sound degraded. Just to add, I am using a couple of Bass Traps and a lot of sound absorption panels.

Please advise if there is something terribly wrong with the approach.
 

Love4sound

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Some more experiments,
today I gave more attention to the "basic setup" before measurement to fine tune settings I need in my MacBook for correct measurements.
This link was helpful :https://www.avsforum.com/threads/rew-for-macos-how-to-setup-your-mac-for-rew.3075106/

I learnt that this "basic setup" is VERY important, level matching by playing pink noise through REW is also VERY important.

Did a comparative of subwoofers response

Red line is "direct mode"
Green line is "AVR set to 7.1 channel"
**since there was a big dip in 45-55 Hz range, I just added some gain in PB 2000 pro to increase from "-18dbfs" to "-15dbfs"
Purple line is "after the gain applied and still no Audessey filter"
** added "-3db" more to PB 2000 pro
Orange line is after applying the "-3db" more gain to make it "-12dbfs"

All above without Audessey filters.

After this experiment, I played some go to scenes and the bass sounder more fuller, louder and also the LF effects were more impactful.

I frequently refer to scenes from John Wick 3 (john hitting hammer on floor", scene from "Arrival" where they are in Helicopter to take them to Alien site .. the helicopter blade blade rotation sound measures about 112 db and I still look for clarity as against muddy sound. I also refer to Dolby Atmos demo scenes from The Tomb Raider.

View attachment 49928

After above I also applied a PEQ on PB 2000 pro to pump up 50 hz and nearby frequencies (I know I should be more concerned about peaks than nulls) to try to boost the overall db in all frequency range of subs.

Result was even pleasant, I will share that curve toon next post.

Time spent brought me some conclusions
1. Audessey MultQT 32 was degrading the loudness the subs should show in scenes where subs need to hit 115db, though theoretically after applying MultQT 32 ... the FR is flatter but it takes away some fun of those sudden surges to "feel the base" and not only "hear it".
2. I have kind of understood where correctly to set the gain on sub and corresponding to that on AVR
3. Changing Phase of PB 2000 pro from "0" (PB 1000 is also on 0 )" to 90 made the bass more punchier and tight. I could hear that helicopter scene from "Arrival" on netflix .. the rotating blades sounded more tight and high db.
4. Achieving more db on Subs has made decay time and decay rate worst but somehow in real life I don't hear the sound degraded. Just to add, I am using a couple of Bass Traps and a lot of sound absorption panels.

Please advise if there is something terribly wrong with the approach.
I am no REW expert but If you want to use the subs without audysey it will be very difficult to correct the dip. Dual identical sub will make it easy and your case adding a mini dsp will be the best solution if you want to use the subs without audyssey. Matching a 12 and 10 inch without mini dsp may end up sounding boomy and muddy. I once tried xtz10.17 and 12.17 but it was chaos.Audysey is a hit or miss and my case it did a very good job in the low bass region 18-45 hz. See how horrible my sub performance is without audysey. 2nd image is pure direct and the third image is with audysey turned off. The below graphs are for a single xtz 12.17.
876EB929-C307-4709-B982-23493F1930F4.jpeg 4678162F-B564-4FF0-8BA7-E47444A8F57F.jpeg EDEAED3F-1B0C-4C67-881D-DE06745CB569.jpeg
 

ankitbhargava

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I am no REW expert but If you want to use the subs without audysey it will be very difficult to correct the dip. Dual identical sub will make it easy and your case adding a mini dsp will be the best solution if you want to use the subs without audyssey. Matching a 12 and 10 inch without mini dsp may end up sounding boomy and muddy. I once tried xtz10.17 and 12.17 but it was chaos.Audysey is a hit or miss and my case it did a very good job in the low bass region 18-45 hz. See how horrible my sub performance is without audysey. 2nd image is pure direct and the third image is with audysey turned off. The below graphs are for a single xtz 12.17.
View attachment 49929 View attachment 49930 View attachment 49931
Somehow Pure Direct looks most scary to my system also
What about the first image you posted? Is it combined response of the 2 subs?
 
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