The problem with Audyssey Dynamic EQ

[-Matt-]

Overall I'm quite happy with what DEQ does to the frequency response (boosting bass and the high end); but I don't like what it does to the surround channel levels. I just made some measurements with different Dynamic EQ settings to confirm my impression that it boosts the surround channels too much.
(Please ignore the generally lumpy response - this isn't about that and I realised that my minidsp sub settings were messed up part way through).

For the centre and front channels the level of the mid frequencies remains fairly constant with different DEQ settings.

But for the surround channels it also boosts the overall level...

The situation is even worse when listening at lower levels...

In the kHz range I think the level should stay roughly where the black line (DEQ off) is. With the DEQ set at 0dB offset it boosts the surrounds by at least 6dB, relative to the fronts.

I assume this is how it is intended to operate (and not an implementation error in my Denon AVC-X receiver). But for me, since I sit a lot closer to the surrounds than the front speakers the boosted surrounds are pretty obnoxious.

For quiet listening in the evening the surrounds are close to me and louder. If I set volume based on the surrounds the centre channel is too quiet - reducing dialogue intelligibility (a common problem). Alternatively if I set volume based on the centre channel I get blasted by loud music and effects from the surrounds, eg when the adverts come on.

Edit: Added poll

 

[abdo123]

Is this rooted in psychoacoustics? Seems too much of a change to be an honest mistake.

 

[-Matt-]

Is this rooted in psychoacoustics? Seems too much of a change to be an honest mistake.

Boosting the lows and highs to achieve perceived equal loudness is well grounded in psychoacoustics; but I don't know if there as an equivalent body of knowledge concerning how the surround channel levels should change?

 

[Dj7675]

Overall I'm quite happy with what DEQ does to the frequency response (boosting bass and the high end); but I don't like what it does to the surround channel levels. I just made some measurements with different Dynamic EQ settings to confirm my impression that it boosts the surround channels too much.
(Please ignore the generally lumpy response - this isn't about that and I realised that my minidsp sub settings were messed up part way through).

For the centre and front channels the level of the mid frequencies remains fairly constant with different DEQ settings.
View attachment 223961

View attachment 223958

But for the surround channels it just boosts the overall level...
View attachment 223959

The situation is even worse when listening at lower levels...
View attachment 223960

(In the kHz range I think the level should stay roughly where the black line (DEQ off) is. With the DEQ set at 0dB offset it boosts the surrounds by at least 6dB, relative to the fronts.

I assume this is how it is intended to operate (and not an implementation error in my Denon AVC-X receiver). But for me, since I sit a lot closer to the surrounds than the front speakers the boosted surrounds are pretty obnoxious.

For quiet listening in the evening the surrounds are close to me and louder. If I set volume based on the surrounds the centre channel is too quiet - reducing dialogue intelligibility (a common problem). Alternatively if I set volume based on the centre channel I get blasted by loud music and effects from the surrounds, eg when the adverts come on.

Thanks for taking the time to measure. It is well known fact and by design. It is a bad decision in my opinion to combine loudness compensation which I think DEQ does really well in combination with the reference level offset setting with surround level boost. Some may like the surround level boosting at lower levels but it always caused me not to use DEQ because I always seemed to have to be adjusting the surround levels… I sent in a request Audyssey to separate the two features several years ago and I’m sure others have as well but it has never changed unfortunately.

 

[abdo123]

I like the idea of Dynamic EQ because i can tune my subbass flat for movies and series while still having a bit of an extra kick for music at a lower level.

Would be interesting if someone can contact Denon and see if this is there for a reason rooted in user experience or science for this. It doesn’t seem like a thing or a decision that anyone would take lightly.

 

[-Matt-]

Thanks for taking the time to measure. It is well known fact and by design. It is a bad decision in my opinion to combine loudness compensation which I think DEQ does really well in combination with the reference level offset setting with surround level boost. Some may like the surround level boosting at lower levels but it always caused me not to use DEQ because I always seemed to have to be adjusting the surround levels… I sent in a request Audyssey to separate the two features several years ago and I’m sure others have as well but it has never changed unfortunately.

Glad to know it isn't just me!

 

[KMO]

The idea is based on an assumption that the surround is "ambience", and hence you are preserving a balance in that ambience by keeping it audible as levels fall.

I believe they got some mixers in to see what they did with their multichannel mixes when adjusting for different playback level, and that was one of the things.

That's probably okay when the content matches that description, and everything is static, but if you've got real moving objects, then it doesn't work. You can hear things get louder as they move behind you. Basically you hear the mixer messing around. Turning the camera in a game with surround audio makes the problem very obvious.

 

[-Matt-]

The idea is based on an assumption that the surround is "ambience", and hence you are preserving a balance in that ambience by keeping it audible as levels fall.

I believe they got some mixers in to see what they did with their multichannel mixes when adjusting for different playback level, and that was one of the things.

That's probably okay when the content matches that description, and everything is static, but if you've got real moving objects, then it doesn't work. You can hear things get louder as they move behind you. Basically you hear the mixer messing around. Turning the camera in a game with surround audio makes the problem very obvious.

This sounds plausible, the trouble is that I like to use the Dolby Surround upmixer with TV viewing which is often just 2 channel. When I do this a lot of music and effects get sent to the surrounds and it can overpower the dialogue on the centre.

Separating DEQ into constant loudness correction and surround level boosting would be a great idea as far as I'm concerned.

 

[ZööZ]

The surround channels are definitely boosted too much, I just started to lower their levels this week when using deq and found that about -3db is roughly enough when watching movies but when gaming it is anything from -6 to -8db. This is from rather short tests so might change my mind later.

Haven't noticed that height channels were boosted though.

 

[-Matt-]

I've added a poll to try to see if this is a widely experienced problem.

 

[ZööZ]

Are you using identical setting for fronts and surrounds?

 

[-Matt-]

Are you using identical setting for fronts and surrounds?

All channels have the levels etc that were auto assigned by Audyssey setup.

 

[SKBubba]

Depending on your Avr, there is a way to set some speaker configuration/adjustment presets. I don't recall exactly, but you may be able to assign them per mode/source. My x3600 does not have this feature. Wish it did. I sometime like to use the dolby upmixer for stereo but with my sub-par center turned off. Denon introduced it on the x3700, but that one feature isn't worth the upgrade for me.

 

[ZööZ]

All channels have the levels etc that were auto assigned by Audyssey setup.

same crossovers? all set as large or small?

Just thinking if the large setting makes a difference how deq is applied per channel.

 

[-Matt-]

same crossovers? all set as large or small?

Just thinking if the large setting makes a difference how deq is applied per channel.

Ah yes, actually I did override Audyssey's suggestions for those settings. All of the crossovers are set to 80Hz, all speakers are set to small (my default).

Audyssey wanted the fronts to be full range (large) and the surrounds to cross at 60Hz.

But really, the part I hope to discuss is the change in surround level (eg. at 2kHz) as a function of DEQ settings. This is well away from the crossover so I don't think these settings should make any difference to the DEQ surround boost effect.

I should mention that the speakers are different too, but regardless, it is clear that the AVR is sending a higher signal level to the surrounds when DEQ is used.

Claimed sensitivity specs:
Front: B&W CDM7NT, 90dB spl (2.83V, 1m)
Centre: B&W CDMCNT, 91dB spl (2.83V, 1m)
Surround: B&W M-1, 85dB spl (2.83V, 1m)

 

[ZööZ]

Ah yes, actually I did override Audyssey's suggestions for those settings. All of the crossovers are set to 80Hz, all speakers are set to small (my default).

Audyssey wanted the fronts to be full range (large) and the surrounds to cross at 60Hz.

But really, the part I hope to discuss is the change in surround level (eg. at 2kHz) as a function of DEQ settings. This is well away from the crossover so I don't think these setting should make any difference to the DEQ surround boost effect.

I should mention that the speakers are different too, but regardless, it is clear that the AVR is sending a higher signal level to the surrounds when DEQ is usedY

Yeah definitely, I did the same only difference is I set all speakers to large and use the lfe+main and 80hz crossover for all so my guess is that my system is doing the same thing. I was just playing detroit become human and noticed that some noises had morre treble or spatial qualities coming from the surrounds vs the fronts, propably because deq doesn't apply the same curve to them so there is more of the 4-20kHz range in them along with the bigger boost.

 

[-Matt-]

Haven't noticed that height channels were boosted though.

I'm not really sure how to go about measuring the height channels. In REW I'm using an hdmi between laptop and AVR and the ASIO driver. It only gives me 8 channels to choose from.

 

[Chromatischism]

Is this rooted in psychoacoustics? Seems too much of a change to be an honest mistake.

I don't think so and it is audibly too much. They are too loud and it pulls Atmos objects too far toward the back of the room.

I'm told that Dynamic Volume on Light can reduce the issue. Otherwise I just reduce the surround channels by between -3 and -5. Also, the rear heights get a big boost, too.

OP: do you really watch movies at -30 to -40? I could see games at -30, but I'd watch movies at -20, and the effect is less there.

 

[-Matt-]

OP: do you really watch movies at -30 to -40? I could see games at -30, but I'd watch movies at -20, and the effect is less there.

Yes, during serious movie watching I'm probably running nearer -20 and dynamic eq is less of a problem. -30ish is for normal tv watching; -40ish is for quieter tv watching, late in the evening (possibly with wife snoozing in the same room). I only have one system so it has to do everything.

I've never tried dynamic volume, I guess I can give it a go.

 

[OCA]

Dynamic EQ (0dB) boost starts from 1kHz and goes all the way down gradually increasing to 12.5dB boost over the Harman curve in sub bass area. This is way too loud by any measure and if it's improving your SQ, there must be a huge dip in your system's mid & bass response. There's also a boost in the air frequencies which compensates for the over dimmed Reference curve HF response but the improvement does not justify the added excessive bass and ringing caused. I have uploaded a video recently with calibrated mic/REW measurements of all Audyssey settings if you want to see the details: