Audyssey midrange compensation and RAAL Sierra Towers / Horizon

[Kisakuku]

I was playing with my Audyssey MultiEQ Pro kit this weekend and couldn't decide if applying midrange compensation (https://audyssey.zendesk.com/entries/410117-Midrange-Compensation) (a dip in the 2 kHz region of the target curve to account for directivity changes around a typical tweeter-to-midrange crossover frequency) made the calibrated response better or not.

I wonder if Dave could chime in on at least the theoretical advantages and disadvantages of applying midrange compensation for Sierra Towers / Horizon with RAAL tweeters. I don't think the exact crossover frequency has ever been confirmed, but I'm assuming it's somewhere around 1.8 kHz as RAAL recommends for 70-20XR. Audyssey Pro also allows to shift the MRC dip from 2 kHz to any desired frequency, so that's also an option.

[davef]

I was playing with my Audyssey MultiEQ Pro kit this weekend and couldn't decide if applying midrange compensation (https://audyssey.zendesk.com/entries/410117-Midrange-Compensation) (a dip in the 2 kHz region of the target curve to account for directivity changes around a typical tweeter-to-midrange crossover frequency) made the calibrated response better or not.

I wonder if Dave could chime in on at least the theoretical advantages and disadvantages of applying midrange compensation for Sierra Towers / Horizon with RAAL tweeters. I don't think the exact crossover frequency has ever been confirmed, but I'm assuming it's somewhere around 1.8 kHz as RAAL recommends for 70-20XR. Audyssey Pro also allows to shift the MRC dip from 2 kHz to any desired frequency, so that's also an option.

Not a proponent of this at all... Basically, what Audyssey is trying to do is to reduce off-axis tweeter "bloom". This is quite common with dome tweeters but any competent loudspeaker designer is already aware of this and has a keen enough ear to determine if there is too much overall energy at these frequencies.

An example of this can be seen in the attached image (first graph). Reducing the bloom by simply reducing the energy at these frequencies is, in my professional opinion, not recommended. In the case of our ribbon speakers, this compensation will do more harm than good as there is no off-axis blooming at any frequency.

attached is the polar response of the ribbon towers (the green graph)

[Kisakuku]

Not a proponent of this at all... Basically, what Audyssey is trying to do is to reduce off-axis tweeter "bloom". This is quite common with dome tweeters but any competent loudspeaker designer is already aware of this and has a keen enough ear to determine if there is too much overall energy at these frequencies.

An example of this can be seen in the attached image (first graph). Reducing the bloom by simply reducing the energy at these frequencies is, in my professional opinion, not recommended. In the case of our ribbon speakers, this compensation will do more harm than good as there is no off-axis blooming at any frequency.

attached is the polar response of the ribbon towers (the green graph)

Dave, thank you for an in-depth response.

Having seen this graph before, I already knew how flat the off-axis response of RAAL is. Being able to disable MRC was one of the reasons why I decided to get the Audyssey Pro kit in the first place. (There is no way to disable it in the consumer Audyssey versions.) I figured I'd ask you about it anyway, since playing with target curves in the Pro software is a fun exercise and I'm usually quite indecisive about what sounds best to me. Case in point: I'm still not sure if for music I prefer the high frequency roll-off of the standard Audyssey target curve or no HF roll-off of Audyssey Flat.

[davef]

Not being able to turn off MRC in non pro-kit Audyssey setups is a serious problem. As a loudspeaker designer I take serious issue with this. Even a loudspeaker that has serious off-axis bloom, amplitude reduction is not the fix. Audyssey can not change directivity and reducing the level not even a band aid and shouldn't simply be based on what Audyssey staff members perceive as "sounding better". I was not aware of this until now and it might explain a lot with regard to a few comments I have received from customers using our ribbon speakers with Audyssey based receivers.

[Kisakuku]

Not being able to turn off MRC in non pro-kit Audyssey setups is a serious problem. As a loudspeaker designer I take serious issue with this. Even a loudspeaker that has serious off-axis bloom, amplitude reduction is not the fix. Audyssey can not change directivity and reducing the level not even a band aid and shouldn't simply be based on what Audyssey staff members perceive as "sounding better". I was not aware of this until now and it might explain a lot with regard to a few comments I have received from customers using our ribbon speakers with Audyssey based receivers.

Good thing I posted the link to MRC info on the Audyssey site then. Indeed, it is somewhat bizarre and arbitrary that you have to spend an extra $700 and quite a bit of extra effort (or pay somebody for a Pro calibration) just to get a flat FR target curve for Audyssey, and that's on top of a relatively expensive Pro kit compatible receiver with Audyssey XT or XT32. I think Audyssey is a very valuable tool for people with less-than-ideal setups, but it can introduce issues of its own.

[FirstReflect]

The 2kHz notch filter is only active in the Audyssey "Movie" setting (formerly known as the "Audyssey curve" in older receivers.

The Audyssey "Music" setting (formerly known as the "Flat" curve in older models) is what you should use if you do not want Audyssey's "opinion" of how things should sound.

Also, if the Receiver or Pre-amp is THX Certified (which pretty much just means Onkyo or Integra when it comes to THX Certified Receivers and Pre-amps that also use Audyssey), when you use one of the THX Listening Modes (THX Cinema, THX Music, THX Game, etc.), Audyssey is automatically set to the "Music" or "Flat" curve, rather than the default "Movie" or "Audyssey" curve.

The reason the THX Listening modes do this is because of THX Re-EQ, which is THX's own "opinion" of how things ought to sound, and THX demanded that their EQ settings should not cascade on top of another non-flat EQ program.

There were a number of AV Receivers that had Audyssey, but did not offer the choice between the "Movie" and "Music" settings. The only had the default "Movie" or "Audyssey" curve. So those particular receivers were the big problem. With those, there was no way to get the "Music" aka. "Flat" curve, unless you upgraded to the Audyssey Pro kit. However, some of those default-only receivers were THX Certified! So there was a work around: you would use a THX Listening mode (which would then force Audyssey into the "Music" or "Flat" curve, even though those were not options that you could select in the regular user menu), and then you could manually turn off THX Re-EQ to get back to a "Flat" setting! Problem was, THX Re-EQ ALWAYS defaults to being on every time you cycle the power of the receiver, or switch to a different listening mode and then switch back. So that was a hassle. But at least it was POSSIBLE to get rid of the 2kHz notch filter that way - haha.

Bottom line, the 2kHz notch filter is not ALWAYS there when using Audyssey. If you have the choice in the user menu to select the "Music" or "Flat" curve, then that disengages the 2kHz notch filter. It's just the default "Movie" or "Audyssey" curves that have the 2kHz notch filter. And using a THX Listening mode with THX Re-EQ manually turned off (every time!) can get you the flat curve with no 2kHz notch filter, too ;)

[Kisakuku]

Bottom line, the 2kHz notch filter is not ALWAYS there when using Audyssey. If you have the choice in the user menu to select the "Music" or "Flat" curve, then that disengages the 2kHz notch filter. It's just the default "Movie" or "Audyssey" curves that have the 2kHz notch filter. And using a THX Listening mode with THX Re-EQ manually turned off (every time!) can get you the flat curve with no 2kHz notch filter, too ;)

Thanks for a helpful explanation, but there's another nuance here. Only one target curve / set of filters is loaded into the receiver after an Audyssey calibration and that becomes the "Movie" curve. The "Music" curve is calculated internally by the receiver by applying a predetermined offset to the "Movie" curve that compensates for the applied HF roll-off and MRC and makes the target curve flat. So it is my understanding that while yes, you can use the "Music" curve to get a flat FR, you can't (without a Pro kit) have a calibration with HF roll-off, but no MRC.

UPDATE: This is incorrect. Audyssey "Music" curve does not compensate for the MRC dip in the "Movie" curve, therefore if one has the dip, so does the other.

[FirstReflect]

So it is my understanding that while yes, you can use the "Music" curve to get a flat FR, you can't (without a Pro kit) have a calibration with HF roll-off, but no MRC.

Yes, absolutely correct. One sort of work around is to use a THX Listening Mode and to actually use the THX Re-EQ default. THX Re-EQ applies a high frequency roll-off. But, of course, it also monkeys with other parts of the frequency response - heh. So it's only a partial work around.

Personally, I'm ok with no high frequency roll-off. I'll take the flat response with no 2kHz notch filter over the "Audyssey" curve, that's for sure! :)

I definitely agree that it's a major pain to have to try and work around (or spend around) a program like Audyssey, though. Especially when it's perfectly capable of delivering the desired results, but it's just hamstrung by marketing decisions :mad:

But yeah, I did want Dave and others to know that you can get rid of the 2kHz notch filter, since that can be a very offensive alteration that is not needed with well designed speakers! But if you want the notch filter gone AND anything other than a flat target curve, you're right back to needing Audyssey Pro (or putting up with THX Re-EQ's "opinion" ;) ).

[ToneDef]

Love these room correction discussions. I have a different flavor (pioneer) and basically turned off the EQ calibration altogether. There are 2 additional components that I am still questioning the merit of: "phase control" and "standing wave correction".

Here is an example of the standing wave correction
No. Filter 1 Filter 2 Filter 3
Freq 74Hz 239Hz 101Hz
Q 2.6 9.8 9.8
ATT 3.5dB 1.0dB 3.5dB

No results are given from phase control, just on or off setting.

These modern components I think have gotten a bit out of control.

Anyone have an opinion on either of these "features"?

[Kisakuku]

But yeah, I did want Dave and others to know that you can get rid of the 2kHz notch filter, since that can be a very offensive alteration that is not needed with well designed speakers! But if you want the notch filter gone AND anything other than a flat target curve, you're right back to needing Audyssey Pro (or putting up with THX Re-EQ's "opinion" ;) ).

So turns out I was too hasty in agreeing with your explanation. The AVS gurus pointed me to these two posts by the Audyssey founder, who has stated that consumer (non-Pro) Audyssey Flat / Music curve has the same MRC dip as the Audyssey / Movie curve. The only way to get rid of it is to use the Pro software, as I have originally stated. (I've updated my post above.)

http://www.avsforum.com/t/795421/official-audyssey-thread-faq-in-post-1/28770#post_18910114

http://www.avsforum.com/t/795421/official-audyssey-thread-faq-in-post-1/33960#post_19714566

[Mpalmieri1203]

Would you guys advise not using the Audyssey at all on my 818 when connected to my towers and Horizon? Are there other options or starter guides as to manual room correction? Or should I just set distances, and SPL level match?

[natetg57]

When I got my new receiver, I was really set on using Audyssey XT. I played around with the settings quite a bit and eventually got it to where I was pretty happy. I ended up using 'manual' and setting the equalizer between 'MultiEq' and 'Flat'. But then, I did some switching between off and on and decided I liked it better off. IMO it is still very handy to use the auto calibration to set levels and distances. I would simply find some well recorded music and try out the different modes.

[Kisakuku]

When I got my new receiver, I was really set on using Audyssey XT. I played around with the settings quite a bit and eventually got it to where I was pretty happy. I ended up using 'manual' and setting the equalizer between 'MultiEq' and 'Flat'. But then, I did some switching between off and on and decided I liked it better off. IMO it is still very handy to use the auto calibration to set levels and distances. I would simply find some well recorded music and try out the different modes.

Nothing wrong with using Manual EQ, but you have to realize that Audyssey is not just a graphic equalizer. All the filters can have a time domain component. Also, you can't use Dynamic EQ or Dynamic Volume with Manual EQ.

[natetg57]

Nothing wrong with using Manual EQ, but you have to realize that Audyssey is not just a graphic equalizer. All the filters can have a time domain component. Also, you can't use Dynamic EQ or Dynamic Volume with Manual EQ.

With MultiEq off, the biggest improvement IMO was with violin music. It sounds more like a real instrument. I cycled through each setting, MultiEq, manual, flat and off. I really wanted to like it. I wonder if the additional processing results in a loss of resolution. Maybe I should try it again with different types of music/movies.

[JustABrah]

Dave,

What's your view on Anthem MRX Anthem Room Correction software? Do you believe it would do more harm than good for Sierra-1 NrT or soon to be Sierra-2s? I'm in a debate to upgrade my avr

[davef]

Dave,

What's your view on Anthem MRX Anthem Room Correction software? Do you believe it would do more harm than good for Sierra-1 NrT or soon to be Sierra-2s? I'm in a debate to upgrade my avr

Sorry -- I have no experience with Anthem Room Correction :( As I recall, comments from customers have ranged from good to bad. I do not think there is an ideal solution.

[jahjd2000]

Regarding the notch filter, what characteristic does it induce? My laymen's takeaway is that it presents a "hole" in the mid range possibly? But I'm not sure I'm interpreting correctly.

[Kisakuku]

Regarding the notch filter, what characteristic does it induce? My laymen's takeaway is that it presents a "hole" in the mid range possibly? But I'm not sure I'm interpreting correctly.

Well, it's not a "hole", it's just a ~2dB dip around 2kHz. Have a look at the 1/3 octave smoothed predicted frequency response curves all the way at the bottom of the Audyssey Pro FAQ post (http://www.avsforum.com/t/1346723/the-audyssey-pro-installer-kit-thread-faq-in-post-1/3030#post_22429521).

[JustaSheep]

Very interesting read. Thanks all for your input.

[FirstReflect]

Interesting!

@Kisakuku , I had the (mis?)information that the 2kHz notch filter was not active in the "Flat" or "Music" setting from a conversation I had with an engineer from Onkyo. So yes, I might have been misinformed about that. The conversation I had was mostly about how the various EQ and volume compensation modes reacted when using THX Listening modes. So the whole matter of how Audyssey would automatically switch over to the "Flat/Music" setting when engaging a THX Listening mode came up, which led to the information about the "Flat/Music" mode taking out the high frequency roll off and the 2kHz notch filter that the default "Audyssey/Movie" mode would apply.

I guess the only way to know for sure is to measure! heh

That's a real shame, though, if there's no way other than Audyssey Pro to remove that 2kHz notch. But to be perfectly honest, with the speakers I've been using in my own home thus far (Energy, Revel, Axiom, tSc), I didn't spot the 2kHz notch just from listening. I DID spot the difference in the high frequency roll off, and a bit of that "house curve" mid-bass adjustment. For music, I actually quite like the THX Music mode (with re-EQ manually turned off). So I'm frequently using that, along with Audyssey. As far as I know (and there's been nothing to indicate that I've been misinformed about THIS part), using that THX Music Listening mode does, indeed, force Audyssey into the "Flat/Music" setting automatically. As I say, I did spot the difference in the high frequency roll off. That adjustment was fairly obvious. The 2kHz notch filter? I honestly can't say that I heard it.

So it'll be very interesting when I get my custom vertical Sierra Horizon Mains with RAAL! They definitely do not "need" or benefit in any way from a notch filter applied near the crossover between the tweeter and mid-range. But it will be very interesting for me to try all the various settings: no Audyssey or THX at all, Audyssey Movie mode, Audyssey Music mode, and THX Music mode with Re-EQ both on and off.

The thing is, in regards to what some other folks in this thread have asked: I truly consider Audyssey to be nothing more than a "cherry on top". I do not think of any auto-setup/EQ program as being "room correction" or "speaker correction". I firmly believe in first getting very good speakers, then setting them up and positioning them correctly. Just as important as all that, though, I consider acoustically treating the room to be a full 50% of the sound system!

So, to my mind, Audyssey (or any other auto-EQ program) really should not have much to do! haha. If the speakers are good, and the room is already good, and everything is set up and positioned properly, there ought to be very little "room correction" needed. And that's pretty much what I have found. I don't hear much of a difference between no Audyssey at all vs. Audyssey in Music mode.

But the reason I'm still a fan of Audyssey MultEQ XT32 w/ SubEQ HT is because I DO hear some differences in the bass! Getting the bass response linear, smooth, and even from seat-to-seat is such a huge challenge. And even with passive bass traps and careful placement of the subs, I've always found a little extra EQ to be very helpful!

So the question becomes (for me) does that 2kHz notch filter make enough of an audible difference (and detriment) to outweigh the benefits of what Audyssey MultEQ XT32 w/ SubEQ HT does for my bass response? Honestly, so far, with the speakers I've owned, that answer has definitely been, "no". In fact, as I say, since I was under the impression that the 2kHz notch filter was deactivated, and I wasn't hearing any obvious impact of having Audyssey turned on (in the Music setting), I really was not giving it a second thought until now!

In any case, thankfully, if the 2kHz notch filter does reveal itself to still be present in the Music setting, and it does create any unwanted results, I CAN upgrade to Audyssey Pro and get rid of it that way! Certainly, this thread has led me to the conclusion that I will be listening very closely for it!

[Kisakuku]

In any case, thankfully, if the 2kHz notch filter does reveal itself to still be present in the Music setting, and it does create any unwanted results, I CAN upgrade to Audyssey Pro and get rid of it that way! Certainly, this thread has led me to the conclusion that I will be listening very closely for it!

Definitely agree with your thinking regarding usefulness and limitations of Audyssey. I do think that the Pro kit is a nice tool to have in your toolbox, if not for MRC and HF roll-off shape flexibility, then at least for the individually calibrated +/-0.5dB sensitive mic vs +/-2dB for the consumer mic. A REW setup for post-calibration measurements is also a must as a reality check. But obviously, any sensible approach would start with good speakers, room treatments and correct placement, all of which should get you 90% of the way.

[GunmetalR56]

I know this is an older thread but I just wanted to add that Chris Kyriakakis has confirmed that the Audyssey Music curve no longer includes MRC in newer AVRs (made in the last 2 years or so).

[Blue Dude]

Resurrecting this thread again with the info that some newer Audyssey receivers can accommodate the Audyssey $20 app, which allows you to turn off MRC for desired speakers.

[GunmetalR56]

Resurrecting this thread again with the info that some newer Audyssey receivers can accommodate the Audyssey $20 app, which allows you to turn off MRC for desired speakers.

Yes! I upgraded to the 4300 for this and it works perfectly. The ability to add a house curve with the app is nice also.

[N Boros]

Gene over at audioholics has said that with the new Audyssey app you can not only set the target curve, but decide where to stop the eq. For example, Dr Floyd Toole thinks that any room eq above 500 Hz does more harm than good, since the frequencies begin to become directional around 500 Hz. Anthem's room eq stops at 5000 Hz, I think. If this is true with Audyssey, then it seems pretty competitive with Anthem, except for being able to switch between multiple eq's on the fly. Honestly the only reason I would want to be able to switch between multiple eq's, would be if I had multiple rows of seating in my home theater, which I don't plan on having. So Audyssey now seems more flexible at a lower cost compared to Anthem with the new app.