Room EQ

[syn08]

Ok, so I said I'll give miniDSP and REW a chance to improve my main system. Got a miniDSP Flex, an UMIK-2 microphone, set up REW with the UMIK calibration file (vertical position), in general everything was done by the book. Level at about 75dB (calibrated with my Lutron Sound Level Meter), did the measurement in the listening position (attached as BDRM...jpg). EQ for full range speakers (no subwoofer, my giant Infinity towers have each 2x12" woofers) Used the calculated target level, 20Hz LF cutoff, 20Hz-20KHz match range, for the purpose of EQ, the measurement was var smoothed (don't ask me why, I just thought that would be right). The result are attached as BDRM EQ...jpg.

Filters were saved and imported in miniDSP Flex. Processed the results (same for both channels), saved the configuration, and now was time for some listening...

Intuitively, the 1/3 octave smoothed EQ results seem logical and pretty good, room modes are also there (attached are also the 1/12 octave smoothed measurements). There is one problem though... Except for the first filter (attenuting the LF response) I can't hear a damn of a difference when bypassing the filters.

1. Does the EQ look "good" (whatever that means)?
2. Is this the expected result (in terms of SQ) but I am too old and deaf to hear an improvement? Perhaps a youngster could hear more (I'm about to summon my daughter and her hubby)?
3. Or did I foolishly spent a nice amount of SQ fluff?

 

[sejarzo]

I've not had the chance to implement my DDRC-24 as my music room is temporarily full of junk from elderly parents' homes until garage sale season starts up, LOL. However, I can say that when I try different EQs on headphones, I don't hear startling differences on music, but the timbre of pink noise almost always changes quite clearly. Do you hear a difference in pink noise when you invoke EQ if you adjust the volume to the same level?

 

[Rednaxela]

Is BDRM EQ.jpg an actual measurement or the predicted response?

Looks like the latter. If so, could you also do a post-EQ measurement?

 

[Rednaxela]

Also, perhaps try the All SPL tab to view and select multiple measurements.

For exporting your graph this button is recommended:

In the dialog, select the 50 dB/decade aspect ratio.

Hope this helps!

 

[will.b]

@syn08
Assuming you have a stereo setup, aren't you meant to use the mic horizontaly and so use the 0deg calibration file?
Have a read through this thread: https://www.audiosciencereview.com/forum/index.php?threads/rew-moving-microphone-method-help.12641/ you might get some usefull tips.

 

[Shadrach]

How reassuring. I came to similar conclusions some years ago.
At that some years ago point I could hear up to 13kHZ. Not much point in messing about trying to get a flat response for frequencies one can't hear.
Mid range, most decent measuring speakers are going to get that about right and household furnishings with a couple of diffusers hidden behaind pictures helps to sort out some of the measured horrors.

When it comes to the bass, particulalry if one is trying to get subs to sound coherent a bit of DSP can work wonders.
REW does what it says on the tin and I think it's a good product. For me trying to get a perfect response in one position just isn't worth all the messing about. I'm not a trained listener thankfully. I don't really enjoy the measuring and tweaking these days. Choice of the right equipment for the environment it's going to perform in helps, as do many of the room arrangement techniques that don't make your living space look like a studio.

 

[syn08]

@syn08
Assuming you have a stereo setup, aren't you meant to use the mic horizontaly and so use the 0deg calibration file?
Have a read through this thread: https://www.audiosciencereview.com/forum/index.php?threads/rew-moving-microphone-method-help.12641/ you might get some usefull tips.

Apparently the vertical mic position is recommended:

Room EQ

Room EQ VST/AU and Room EQ for Foobar2000

mathaudio.com

The Dirac team also recommends the mic in the vertical position. So does miniDSP:

UMIK-1 + MathAudio EQ

miniDSP is a leading manufacturer of Digital Audio Signal Processors for the HomeTheater, Hifi, headphone and Automotive market. Join our large community of Audiophiles, Engineers and DIYers using our innovative products.

www.minidsp.com

 

[mglobe]

Look up the Harman curves. They are closer to what you want at the listening position than a flat curve that you are targeting.

 

[will.b]

Apparently the vertical mic position is recommended:

Room EQ

Room EQ VST/AU and Room EQ for Foobar2000

mathaudio.com

The Dirac team also recommends the mic in the vertical position. So does miniDSP:

UMIK-1 + MathAudio EQ

miniDSP is a leading manufacturer of Digital Audio Signal Processors for the HomeTheater, Hifi, headphone and Automotive market. Join our large community of Audiophiles, Engineers and DIYers using our innovative products.

www.minidsp.com

That's odd, on the product page it says otherwise:

Which calibration file should I use and where to point the UMIK-2?​

We provide two calibration files to be used depending on your application.


- For stereo system (e.g. 2ch dirac live, single speaker measurement), use the 0deg file and point the UMIK-2 at the speakers
- For multichannel system (E.g. 5.1/7.1) or a surround application where multiple speakers are spreadout around the room, use the 90deg file and point the UMIK-2 at the ceiling.

UMIK-2

USB Reference Measurement Microphone, 32bit/44.1~192kHz, ASIO drivers, 1/2" capsule, Low noise floor, Unique Calibration file, REW and Dirac Live integration

www.minidsp.com

I thought you were using REW with the FLEX not foobar and the mathaudio plugin?

 

[HarmonicTHD]

That's odd, on the product page it says otherwise:

Which calibration file should I use and where to point the UMIK-2?​

We provide two calibration files to be used depending on your application.


- For stereo system (e.g. 2ch dirac live, single speaker measurement), use the 0deg file and point the UMIK-2 at the speakers
- For multichannel system (E.g. 5.1/7.1) or a surround application where multiple speakers are spreadout around the room, use the 90deg file and point the UMIK-2 at the ceiling.

UMIK-2

USB Reference Measurement Microphone, 32bit/44.1~192kHz, ASIO drivers, 1/2" capsule, Low noise floor, Unique Calibration file, REW and Dirac Live integration

www.minidsp.com

I thought you were using REW with the FLEX not foobar and the mathaudio plugin?

Assuming you want to measure and subsequently optimize the frequency response in your room at your listening position (Room EQ) you always point the mic to the ceiling (no matter if 2.0 or 7.x.x) and use the 90deg calib file. This way it captures also the indirect sound (reflected by your room) in simple words.

The 0deg calib file is mainly used when measuring individual drivers (at usually around 1m) distance and trying to exclude the room influence onto your measurements, again in simple words.

See also the first video for REW from which you can also derive the filters for eg. Dirac, Audyssey or APO EQ or whatever you use for Room EQ.

REW room acoustics and audio device measurement and analysis software

REW is free software for room acoustic measurement, loudspeaker measurement and audio device measurement and analysis

www.roomeqwizard.com

 

[will.b]

Assuming you want to measure and subsequently optimize the frequency response in your room at your listening position (Room EQ) you always point the mic to the ceiling (no matter if 2.0 or 7.x.x) and use the 90deg calib file. This way it captures also the indirect sound (reflected by your room) in simple words.

The 0deg calib file is mainly used when measuring individual drivers (at usually around 1m) distance and trying to exclude the room influence onto your measurements, again in simple words.

See also the first video for REW from which you can also derive the filters for eg. Dirac, Audyssey or APO EQ or whatever you use for Room EQ.

REW room acoustics and audio device measurement and analysis software

REW is free software for room acoustic measurement, loudspeaker measurement and audio device measurement and analysis

www.roomeqwizard.com

I'm not an expert but isn't the UMIK-2 an omnidirectional mic, so designed to capture sound equally from all directions?

 

[HarmonicTHD]

I'm not an expert but isn't the UMIK-2 an omnidirectional mic, so designed to capture sound equally from all directions?

All mics for the Room EQ purpose are omnidirectional regardless if UMIK2, UMIK1, the Neumann MA1 mic or the Genelec GLM mic - you all point them upwards (at the ceiling). See the respective websites tutorials for REW, MiniDSP / Dirac, Neumann or Genelec. The difference between UMIK1 and 2 is mainly SNR and price, but UMIK1 is good enough for Room EQ (where SNR only plays a minor role).

For example for Neumann MA1 (same for Genelec and the others) "Calibration curve is valid for 90° angle of incidence (i.e. microphone pointed vertically)"

MA 1

MA 1 - - KH 420,KH 310 A,KH 120 A G,KH 750 DSP,KH 80 DSP A G,KH 120 A W,KH 420 + DIM 1,KH 120 D G,KH 310 D,KH 80 DSP A W,Electronics - Sennheiser Discover True Sound

en-de.neumann.com

 

[will.b]

This is a bit strange.

I use the UMIK1 myself and from a miniDSP support page it says otherwise:

Which direction should I point the UMIK-1?

The UMIK-1 comes with two unique calibration files depending on two types of measurements: - 0deg: This calibration file is for Stereo and 2.1/2.2 systems. Point the microphone towards the sound source being measured. In the case of a Dirac live...

support.minidsp.com

 

[thewas]

It should be added even for those measurements "omnis" there is always a different response for 0° frontal and 90° side direction at the upper octaves so you should use the according calibration, here exemplary:

Source and more: https://www.beyerdynamic.de/mm-1.html

Now for the orientation during for room correction, each is a compromise, with the 0° mic rotation and calibration you tend to overestimate a bit the direct sound proportion in the last octave while with the 90° the reflected sound proportion.

 

[HarmonicTHD]

This is a bit strange.

I use the UMIK1 myself and from a miniDSP support page it says otherwise:

Which direction should I point the UMIK-1?

The UMIK-1 comes with two unique calibration files depending on two types of measurements: - 0deg: This calibration file is for Stereo and 2.1/2.2 systems. Point the microphone towards the sound source being measured. In the case of a Dirac live...

support.minidsp.com

You find the detailed answer here:

https://www.minidsp.com/images/documents/miniDSP%20UMIK-2-User%20Manual.pdf

 

[will.b]

You find the detailed answer here:

https://www.minidsp.com/images/documents/miniDSP%20UMIK-2-User%20Manual.pdf

Thanks.

From reading that, both orientations are valid for stereo use with respective calibration file, but the vertical orientation should always be used for multichannel/surround setups.

 

[thewas]

From reading that, both orientations are valid for stereo use with respective calibration file, but the vertical orientation should always be used for multichannel/surround setups.

From acoustic point of view someone could use also the 0° orientation for multichannel setup (rotating the mic to each measured loudspeaker), that the 90° orientation is typically used is just a matter of practicality and speed.

 

[pma]

2. Is this the expected result (in terms of SQ) but I am too old and deaf to hear an improvement? Perhaps a youngster could hear more (I'm about to summon my daughter and her hubby)?

When I average responses from 3 different listening position distances I get the result as below. Frankly, I am not a fan of room EQ.