Audyssey's Next Generation of Room Correction (MultEQ-X)

[Newman]

Asking for a measurement isn’t the same as disputing, though.

 

[GalZohar]

It's not just about what Dirac does, but also what it does differently than Audyssey, and whether that (what it does and/or what it does differently) actually translate to better sound, backed by measurements. Supposedly Audyssey also uses the FIR filters to correct phase (at least according to the Audyssey developers). However there are differences in the final results (mostly phase, as amplitude corrections seem almost identical when identical target curves are applied), so I am wondering if one is actually better than the other (with measurements to back up the improvement).

 

[Dumdum]

Dirac Live measurements before/after - Gearspace.com

I've did my first tests with Dirac Live today. Attached you'll find before/after frequency response and decay times. Here's the dropbox link for the md

gearspace.com

 

[Dumdum]

It's not just about what Dirac does, but also what it does differently than Audyssey, and whether that (what it does and/or what it does differently) actually translate to better sound, backed by measurements. Supposedly Audyssey also uses the FIR filters to correct phase (at least according to the Audyssey developers). However there are differences in the final results (mostly phase, as amplitude corrections seem almost identical when identical target curves are applied), so I am wondering if one is actually better than the other (with measurements to back up the improvement).

from my measurements they aren’t correcting phase with fir in audessey I didn’t think, I will disable the audessey on mine and capture the front speakers impulse and phase and repeat with audessey implemented. That I can do, and from what I saw, it doesn’t do what Dirac does with regard to phase and impulse response from memory, I didn’t take impulse response as I didn’t have the tab open and as I was matching mono subs to fronts I only measured left and right together

I am still going to spend 160 quid on this software to give me extra functionality, it’s only the same as buying a better dsp for me, the none transferability sucks but that’s their perogative, I am more than capable of making use of the extra processing power it gives in eq and timing, there’s a few suggestions I’ve made to them though about improvements I’d like to see to make it easier to tune the setup

 

[Senior NEET Engineer]

Is the license linked to my WIndows account? Or will I lose it when changing computers?

 

[Dumdum]

Yes it’s on your windows account

 

[prerich]

Is the license linked to my WIndows account? Or will I lose it when changing computers?

It's linked to your account. However if you sign in your account on another PC, you can still use the software.

 

[Reverend Slim]

There's some interesting new info over at AVSforum that is relevant to the differing distance/delay settings we get in MultEQ-X. Turns out that D&M receivers may be erroneously using 300m/s as the speed of sound rather than 343m/s, resulting in time alignment issues when using the in-AVR or phone app versions that are corrected when using MultEQ-X. This might explain the improvements people have heard.

 

[HarmonicTHD]

There's some interesting new info over at AVSforum that is relevant to the differing distance/delay settings we get in MultEQ-X. Turns out that D&M receivers may be erroneously using 300m/s as the speed of sound rather than 343m/s, resulting in time alignment issues when using the in-AVR or phone app versions that are corrected when using MultEQ-X. This might explain the improvements people have heard.

Oh really. How definitive is this? Did Denon confirm it officially?

 

[Reverend Slim]

Oh really. How definitive is this? Did Denon confirm it officially?

Denon hasn't weighed in directly, but Audyssey confirmed that their team found a 14.3% anomaly in delay, which lines up to what users are detecting with REW. Audyssey also stated that the Denon is natively metric, so using the metric version of the settings is more precise. User named Easley is following up with Audyssey to confirm some things, but it looks like if you're not using MultEQ-X, you can just multiply your speaker distances by 0.857 and make the change yourself in the AVR or the phone app to get the same results you would with MultEQ-X. Interesting stuff.

 

[HarmonicTHD]

Denon hasn't weighed in directly, but Audyssey confirmed that their team found a 14.3% anomaly in delay, which lines up to what users are detecting with REW. Audyssey also stated that the Denon is natively metric, so using the metric version of the settings is more precise. User named Easley is following up with Audyssey to confirm some things, but it looks like if you're not using MultEQ-X, you can just multiply your speaker distances by 0.857 and make the change yourself in the AVR or the phone app to get the same results you would with MultEQ-X. Interesting stuff.

Thx. Do you have the link, so I don’t need to bother you and follow the developments myself.

edit. Never mind found it.




Does the factor apply to metric or imperial or both?

 

[Reverend Slim]

Does the factor apply to metric or imperial or both?

I'm unclear yet as to the difference between metric and imperial. Sounds like swapping between units on the AVR itself produces some error in the conversion and that Audyssey was recommending setting it to metric. Will be interesting to follow going forward, but it's good to finally have some answer as to how the MultEQ-X distances differ after sending the results to the AVR. Could very well explain why I was getting better sub-to-speaker integration with MEQX (and give people using the app or in-AVR versions the math to get similar results).

 

[HarmonicTHD]

I'm unclear yet as to the difference between metric and imperial. Sounds like swapping between units on the AVR itself produces some error in the conversion and that Audyssey was recommending setting it to metric. Will be interesting to follow going forward, but it's good to finally have some answer as to how the MultEQ-X distances differ after sending the results to the AVR. Could very well explain why I was getting better sub-to-speaker integration with MEQX (and give people using the app or in-AVR versions the math to get similar results).

Yes. I also use the MS app.

As far as I understood it. Without the MSApp: If you use imperial, set it to metric. And either way multiply by that factor you quoted to account for the 14 something percent difference in the speed of sound.

 

[KMO]

it looks like if you're not using MultEQ-X, you can just multiply your speaker distances by 0.857 and make the change yourself in the AVR or the phone app to get the same results you would with MultEQ-X. Interesting stuff.

Yes, but it's 0.875.

Not the result of a simple digit transposition, but the way the numbers work out - that's the correct value for the 300/343 speed of sound conversion, which is 100/114.3.

The 0.857 was the initial assumed factor of (100-14.3)/100 for a 14.3% reduction, based on the Audyssey support person's comment, before we figured out the derivation of that 14.3%.

(And you can also get great main speaker alignment results - assuming simple passive speakers - just by using a tape measure and multiplying your measurements by 300/343. Previously using a tape measurement never worked well for me, but it turns out that was because of the missing 300/343 fudge).

 

[HarmonicTHD]

Yes, but it's 0.875.

Not the result of a simple digit transposition, but the way the numbers work out - that's the correct value for the 300/343 speed of sound conversion, which is 100/114.3.

The 0.857 was the initial assumed factor of (100-14.3)/100 for a 14.3% reduction, based on the Audyssey support person's comment, before we figured out the derivation of that 14.3%.

(And you can also get great main speaker alignment results - assuming simple passive speakers - just by using a tape measure and multiplying your measurements by 300/343. Previously using a tape measurement never worked well for me, but it turns out that was because of the missing 300/343 fudge).

On the AVs forum, I saw you had a good part in figuring this out. Thx for that.

 

[KMO]

The real purist will actually fine-tune the adjustment factor based on their thermostat setting. The 343m/s is for 20 degrees C, which I think is probably a bit lower than my preferred living-room temperature.

(But it does appear to be the number that MultEQ-X is using, as you can confirm the 300/343 factor by comparing what it puts in the AVR to what it shows in the app).

(Edit: and, actually, if adjusting numbers from some calibration tool, they've got a real time measurement at current room temperature and converted to distance using a fixed 343, so you need to stick with that. The reported distance could be a tad off if there was a temperature difference from 20C, but it will be the correct delay. Only people using tape measures would want to fine tune the 343 number to get a better delay estimate.)

 

[HarmonicTHD]

The real purist will actually fine-tune the adjustment factor based on their thermostat setting. The 343m/s is for 20 degrees C, which I think is probably a bit lower than my preferred living-room temperature.

(But it does appear to be the number that MultEQ-X is using, as you can confirm the 300/343 factor by comparing what it puts in the AVR to what it shows in the app).

(Edit: and, actually, if adjusting numbers from some calibration tool, they've got a real time measurement at current room temperature and converted to distance using a fixed 343, so you need to stick with that. The reported distance could be a tad off if there was a temperature difference from 20C, but it will be the correct delay. Only people using tape measures would want to fine tune the 343 number to get a better delay estimate.)

Before I used the MultiEQX software, the distances measured for the mains were accurate to the last cm. (measured by laser). The sub however was always „off“, so I thought this always as an acoustic „distance“. I might be wrong though.

Personally I couldn’t care less about the accuracy of distance measurements as I always saw it as a delay. However it is utmost confusing for those you might not have all this info.

 

[GalZohar]

The sub distance takes into account the built-in DSP in the subwoofer, that's why it gets extra distance. That still often won't properly phase-align it with your mains at the crossover, though, so manual modification of subwoofer distance is usually necessary.

 

[Reverend Slim]

Yes, but it's 0.875.

Not the result of a simple digit transposition, but the way the numbers work out - that's the correct value for the 300/343 speed of sound conversion, which is 100/114.3.

The 0.857 was the initial assumed factor of (100-14.3)/100 for a 14.3% reduction, based on the Audyssey support person's comment, before we figured out the derivation of that 14.3%.

(And you can also get great main speaker alignment results - assuming simple passive speakers - just by using a tape measure and multiplying your measurements by 300/343. Previously using a tape measurement never worked well for me, but it turns out that was because of the missing 300/343 fudge).

Probably too late to dig into now, but at one point, there was an update to MEQX that seemed to change how the distances translated. I re-uploaded an existing project in the app after that update and my AVR got different distances sent to it. Pulled back up my old numbers and how they translated, and they didn't quite match up with the theory being kicked around now. But I'm glad people have finally figured out what's going on. Thanks for your part in it!

 

[Dumdum]

The sub distance takes into account the built-in DSP in the subwoofer, that's why it gets extra distance. That still often won't properly phase-align it with your mains at the crossover, though, so manual modification of subwoofer distance is usually necessary.

The crossover counts on both sides of the crossover slope matching a predetermined curve, from what I’ve seen the Denon apples a 12db slope to the fronts and doesn’t apply any eq to the crossover slope which needs doing…

I used smaart on my fronts and effectively dialled in the subs using a larger distance in the av receiver (the max I could as there is a 5m limit from shortest to furthest distance) and then delaying both subs in my dsp and inverting the phase of the sub to get it timed bang on, I get good summation with varying level (and therefore acoustic crossover point)

I’ve also knocked the sub back 3db and found a very nice setting for music and movies both