"Official" Audyssey thread (FAQ in post #1) - Page 32

Thanks again for your input

Phil

Hi Chris,
I noticed my Paradigm CC-190 seems a bit compressed sounding. I would think it should sound better or different because it went from Paradigm Cinema Series 70 center below the TV to above the TV back about 12" mounted to the wall. I didn't know what to do so I turned off Tone control and this seemed to help some what a make it more spatial. I'm running the Denon 2808ci amp. I don't know if you know what tone control does?

Thanks
Phil

My understanding is that Audyssey is taking in information continuously while doing a series of chirps. ie while doing one test of all the speakers. At the end of that series of tests, when the display says to move the mic, then you can move the mic, and make noise if you like. Note Chris's earlier post that states that even the fan noise from your projector can possibly upset your readings.

Chris
Apart from the main listening position, which should always be measured first, do the other testing locations have priority ratings? ie is there an order in which locations should be tested?

Here's what Chris told me in an email.

"After the first measurement is taken in the center of the couch, the remaining order of the measurements doesn't matter at all. It's just the first one that has to be in the center."

Unfortunately not. The new method for high subwoofer resolution was implemented the year after those models came out.

Chris

The Tone Control does just that: controls bass and treble. When you defeat it those manual settings are turned off. But setting it to 0 and turning it off should be identical.

Chris

Don't move the mic until the display tells you to. MultEQ also measures background noise for a short time after the test signal.

Chris

The correct statement for Double Bass is that the content that is supposed to be sent to the sub is copied to the main speakers. If your main speakers can't handle that low bass very well (don't go by the marketing specs) then you could be overdriving them and getting the effect you are hearing. Have you tried just setting them to small and turning off Double Bass so only the sub is responsible for the lowest octave?

Chris

Chris,

I asked this question several days ago now but I haven't seen an answer.

You were saying that you thing the crossover setting for the sub/LFE channel should be set at 120 Hz. When I do the set-up process with my Denon 2807 it gets set to 80 Hz. I can and have changed it to 120 Hz but I was wondering whether Audyssey applies correction all the way up to 120 Hz or higher or whether it stops at the crossover frequency.

The question is more for interest's sake since everything sounds fine with that crossover set to 120 Hz.

This is exactly opposite of what I thought!!! Do you mean that also the LFE is copied to the main speakers?

I always turn off the double bass and I set the mains to a cross over frequency related to the marketing specs otherwise I get that muddy sound.

May be if I list my speakers brand and specs you can have a better view of the system.
FRONT:
Sonus Faber Minima Amator 55-22000 4 Ohms 25-150W 88 dB/1W 1m
CENTER:
Klipsch RCX-4 92-20000 8 Ohms Compatible 75W (300W peak) 94 dB @ 2.83 volts/1m
SURROUND:
Klipsch RSX-3 116-20000 8 Ohms Compatible 40 W (160W peak) 89 dB @ 2.83/volts 1m
BACK SURROUND:
Infinity Infinitesimal Micro Satellites 150-22000 6 Ohms 10-50 Watt RMS 87dB (1 watt/1 meter)
SUBWOOFER:
Infinity Infinitesimal Micro Subwoofer 50-150 6 Ohms 10-100 Watt dual coil 87dB (1 watt/1 meter)

All is powered by the Onkyo 875 but the sub which is connected to a SONY TA-N80ES capable of 200 W per channel RMS over 8 Ohms.
I have connected the two coils of the sub in series so I have about 12 Ohms and wired the amp in mono.

When I run the Audyssey set up, all the mains, but the Back surround, are rated full band and the double bass is switched on.

After many trials, the best sound I can get is with the following settings.

Front 50 Hz
Center 90 Hz
Surround 100 Hz
Surround back 120 Hz
LPF of LFE 120 Hz
Double bass off

Subwoofer THX yes
BGC on

The levels set by Audyssey are
Front -1.5
Center -4.0
Right -3.0
Surr right -5.5
Surr Back R -7.5
Surr Back L -10.0
Surr left -4.5
Subwoofer -11.5

I attach also some pictures of my living dining home theater room.
The first picture shows the Sonus faber the center (below the LCD) and the sub (right of the right front speaker.
The second picture shows the Right surround and the Right Back surround (behind the green glass bowl)
The third and fourth pictures show the seat one (where the notebook is) and the left surround (partially hidden by the strange wire sculpture) and the left back surround close to the oval metal vase and the telephone.

Ok if you had enough time to read up to here, please let me know what you think. If not, I understand......

ciao

enzo

Thank you very much for your answer.

This means the MultEQ XT in the AVR-2807 is more advanced than the one in the AVR-3806 and AVR-4306?

The Marantz SR7001/SR8001 arrived the year after those models came out. Do the Marantz models already have built-in this new method for high subwoofer resolution although it is only MultEQ and not MultEQ XT?

And then I would like to repeat my unanswered questions from post #737
http://www.avsforum.com/avs-vb/showt...6#post12854086

I am intrigued by Chris' explanation of LFE and the 120hz idea.

So now I have a silly and somewhat embarrassing question. Hopefully someone else was just too embarrassed to ask and will benefit as well.

If I set the LFE in my receiver (Onkyo 905) to 120hz should I also change the crossover on the back of the sub? Currently it is at 80ish or so.

Thanks for your help!

Mia

Set it on your subwoofer to max or, if available, bypass it completely.

Terrific! I will do just that!

Thank you! *hugs*

Mia

Hi David, I am a little unclear if you are asking about the subwoofer crossover to the main channels or the LFE lowpass for the LFE track. I believe it is that latter and so the answer is: MultEQ correction for the subwoofer is applied up to the highest frequency crossover found for the main speakers. MultEQ doesn't even look at or know about the LFE lowpass frequency.

Regards,
Chris

No, that would only happen if you set Subwoofer = None. I was referring to the lowpassed signal from the main speakers after bass management.

I am puzzled by the fact that you say that Double Bass is turned on after you run Audyssey. MultEQ doesn't "talk" to that setting at all. It is a manual choice that can be made outside of MultEQ. I wonder, if in the Onkyo GUI it stays on after you have left it on before calibration. You are doing the right thing to turn off Double Bass in your case. I just don't see why it's turning on automatically...

The trim values that MultEQ finds seem believable given how close your back surround speakers are. I would recommend two things to try with the subwoofer: (i) turn off BGC and (ii) turn down the gain on the back of the sub because MultEQ finds it to be too high (it's telling you to cut by 11 dB). Then rerun MultEQ.

Regards,
Chris

And don't forget that you have to run MultEQ again after you do that.

Chris

Chris:

Hi! Thanks for your reply. Many of my questions were addressed. In your post # 926 You said:

"MultEQ XT says "up to 8 positions". The reason for 6 in the 2807 is because of memory limitations in the DSP architecture that does not allow us to store 8. This is really not a big difference for typical home listening rooms. The filter resolution and the subwoofer resolution in the 2807 is identical to all other receiver-based MultEQ XT products"

I was hoping you could tell me, in numbers and spacing just what these "filter resolutions" and "subwoofer resolutions" are.

Could you provide titles and dates for the pertinent papers you mentioned and the book title and publisher? I have access to the University library here in Tennessee, and I could either find them there, or order copies, I might even be able to still understand some of that stuff.

Your time devoted to participation in this forum is much appreciated!

Regards

Donald

I changed the crossover back to 40Hz for the front speakers as Audyssey had initially set and re-ran Room eq wizard. I found that Audyssey does in fact take into account any changes that are made. Unfortunately I didn't save the FR but with a crossover of 40Hz up front my FR dipped since my front towers don't have the ability to play as loud and forceful as my subs. The dip was from 40Hz to about 70Hz and was at least 8-10db in diffeence. Once I put the crossover back to 80Hz things returned to normal.

I also moved my chairs over about 6 inches to the right and found that it helped with that nasty dip I initially had. I still have a dip, but it is over much less frequencies. Below please find the before and after FR of moving just 6 inches, the first attachment is the before and the second is the after.

Also, can someone explain why it is recommended to change the crossover to 120Hz for lfe instead of 80Hz? If it was explained aleady I missed it, if so, please point me to the thread.

Thanks

I have an 8001, and ran Audyssey on it. I went back and forth between Audyseey and manual tweaking with Avia/SPL.

When I got the 8002, I tried Audyseey again. When it finished, it had REV next to the value it calculated for the sub (Axiom's EP500).

the phase control on the sub is set to 0, and it faces the same direction as the mains.

Does the REV mean that I should reverse the phase? When I tried the sub phase check in Avia, I really couldn't tell the difference (switching the phase control from 0 to 180 and back).

I've got an Inegra 9.8 and have been playing with Audyssey and haven't been able to get results I'm happy with. Just generally speaking the highs sound muddy compared to having the EQ off. There's just no sparkle in the upper frequencies, like a blanket has been thrown over the speakers.

I'm making sure the room is quiet, mic pointed at cieling on (makeshift) tripod at ear level from all measuring positions. So far I've run from 3 positions during setup since those are the only positions my wife and I genereally sit in when watching/listening.

I've tweaked sizes and crossover points following calibration, which didn't help much. Strangely it set my Epos ELS 3 surrounds as "Full", which I changed. Also changed the crossover points on my Quads in front (also detected as "Full" - played around with this one a bit.)

Generally speaking, I think my room is probably pretty good to start with, but I'd like to see if Audyssey can make it better. Does anyone have any suggestions on how I can improve my results? Thanks for any assistance!

Humm I am not sure I understood this. As far as I know till now, the sub receives only the x.1 i.e. LFE channel signal if all the speakers are set to Full band. Or not?
If the main speakers are set to Full Band, which lowpassed signal would be copied to the Mains? They should already receive all what is destinated to them!! I am confused.

Double bass is turned on automatically, in the Onkyo, if you set the main front to full band. Because during setup Audyssey finds the speakers to be full band (or pass the info that below a certain secret frequency the speakers are able to not go down more than 3 dB) then the Onkyo sets automatically the Double bass on.

Ok I will do that. I have the option of input the sub signal in the amp as fixed or variable. I used fixed in order to be sure that no one could accidentally turn the knob on the amp and so destroy the sub.
Actually the BGC on does not change much the sub sound.

Thank again.
Something tells me that you took a look to my pictures. Appreciated.

Ciao from Italy.

I think that's getting into the 'secret sauce' so I doubt Chris will answer other than in a general way. If you want to research the subject, google linear phase FIR filters.

In the Onkyos (at least the Onkyo 805 that I have), if the front speakers are set to full range, double bass automatically comes on by default.

I just re-ran audyssey today and noticed that -- as my fronts get set to full range when I run Audyssey. When you set a x-over (I use 80hz) for the fronts, the double bass setting turns off.

The original poster can simply go into the OSD and see that by setting the front speakers back to full range (temporarily).

Since most people should be setting a x-over for their fronts (after running Audyssey), this shouldn't be an issue.

Chris,

Thanks for that. Yes, I was asking about the LFE track.

I kind of hoped that Audyssey would provide correction to the upper frequency limit for that track since the crossovers for all my main speakers get set to 60 Hz and the sub crossover setting to 80 Hz.

As I said, the question was more for interest's sake as I suspect there's very little between 60 Hz and 120 Hz on most LFE tracks and I haven't noticed any nasty audible differences from resetting the sub crossover setting to 120 Hz.

Because of the proprietary nature of the way we create FIR filters, we do not publish the resolution. Suffice it to say that it is in the "few Hz" range for the subwoofer.


Well...you asked for it. Sunil Bharitkar is my former PhD student who performed a lot of this research as part of his PhD dissertation. He is now Audyssey VP of Research. Phil Hilmes is a former researcher at the USC Immersive Audio Lab and he is responsible for writing most of the early DSP code for MultEQ. He is now VP of Engineering at Audyssey.

Book
S. Bharitkar and C. Kyriakakis, Immersive Audio Signal Processing, Springer-Verlag, New York, (2006).

Papers
S. Bharitkar and C. Kyriakakis, Visualization of Multiple Listener Room Acoustic Equalization with Sammon Map, IEEE Transactions on Speech and Audio Processing, 15(2), 542-551, (2007).

S. Bharitkar and C. Kyriakakis, Loudspeaker and Room Response Modeling with Psychoacoustic Warping, Linear Prediction, and Parametric Filters, in Proc. 121st AES
Conv., San Francisco, Oct. 2006.

S. Bharitkar, Y. Zhang, and C. Kyriakakis, Room Acoustic Response Modeling and Equalization with Linear Predictive Coding and Parametric Filters for Speech and Audio Enhancement, in Proc. 40th IEEE Asilomar Conf. on Signals, Systems,& Computers, Pacific Grove (CA), Oct. 2006.

S. Bharitkar and C. Kyriakakis, Cascaded FIR Filters for Multiple ListenerLow Frequency Room Acoustic Equalization, accepted in 2006 IEEE Intl. Conf. Acoust., Speech, & Signal Proc. (ICASSP-2006), Toulouse, France, May 2006.

S. Bharitkar and C. Kyriakakis, Comparison Between Time Delay Based and Nonuniform Phase Based Equalization for Multichannel Loudspeaker-Room Responses, 39th IEEE Asilomar Conference on Signals, Systems, & Computers, Pacific Grove, CA, November, 2005.

S. Bharitkar and C. Kyriakakis, Optimization of the Bass Management Filter Parameters for Multichannel Audio Applications, 39th IEEE Asilomar Conference on Signals, Systems, & Computers, Pacific Grove, CA, November, 2005.

S. Bharitkar and C. Kyriakakis, Objective Function for Automatic Multiposition Equalization and Bass Management Filter Selection, Audio Engineering Society, New York, October, 2005.

S. Bharitkar and C. Kyriakakis, Optimization of Crossover Frequency and Crossover Region Response for Multichannel Acoustic Applications, 13th European Signal Processing Conference (EUSIPCO 2005), Antalya, Turkey, September, 2005.

S. Bharitkar and C. Kyriakakis, Nonlinear Projection Algorithm for Evaluating Multiple Listener Equalization Algorithm Performance, Proceedings of the 117th Convention of the Audio Engineering Society, New York, October, 2004.

S. Bharitkar and C. Kyriakakis, Robustness of Spatial Average Equalization: A Statistical Reverberation Model Approach, Journal of the Acoustical Society of America, 116(6), 3491-3497, (2004).

S. Bharitkar, P. Hilmes, C. Kyriakakis, Sensitivity of Multichannel Room Equalization to Listener Position, in Proceedings of the AES 115th Convention, NY, Oct 2003.

S. Bharitkar and C. Kyriakakis, The Influence of Reverberation on Multichannel Equalization: An Experimental Comparison Between Methods, Proc. 37th IEEE Asilomar Conference on Signals, Systems, & Computers, Pacific Grove, CA. Nov. 2003. (Best Paper Award)

S. Bharitkar and C. Kyriakakis, A Comparison Between Multi-channel Audio Equalization Filters Using Warping, 2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics (WASPAA 2003), New Paltz, NY. Oct. 2003.

S. Bharitkar and C. Kyriakakis, Sensitivity of multichannel room equalization to listener position, Proc. IEEE Conf. on Multimedia & Expo (ICME), Baltimore. July 2003.

S. Bharitkar, P. Hilmes, C. Kyriakakis, Analysis of Multiple Listener Equalization Performance Due to Displacement Effects,145th Meeting of the Acoustical Soc. America. Nashville (TN). May 2003.

S. Bharitkar and C. Kyriakakis, Perceptual Multiple Location Equalization with Clustering, in Proc. 36th IEEE Asilomar Conference on Signals, Systems, & Computers, Pacific Grove, CA, Nov. 2002.

S. Bharitkar, P. Hilmes, and C. Kyriakakis, Robustness of Spatial Averaging Equalization Methods: A Statistical Approach, in Proc. 36th IEEE Asilomar Conference on Signals, Systems, & Computers, Pacific Grove, CA, Nov. 2002.

S. Bharitkar and C. Kyriakakis, Visualization of Multiple Listener Room Response Equalization using Sammon Map, in Proc. IEEE Intl. Conf. on Multimedia & Expo (ICME 2002), Lausanne, Switzerland, Aug. 2002.

S. Bharitkar, P. Hilmes, and C. Kyriakakis, A Statistical Analysis of the Robustness of Room Equalization Using Spatial Averaging, Preprint No. 5669, presented at the 113th AES Convention, Los Angeles, CA, October, 2002.

S. Bharitkar and C. Kyriakakis, A Cluster Centroid Method for Room Response Equalization at Multiple Locations, IEEE WASPAA 2001, Mohonk, NY (WASPAA: Workshop on Applications of Signal Processing to Audio and Acoustics).

S. Bharitkar and C. Kyriakakis, A Classification Scheme for Room Acoustical Responses, ICASSP 2001, Salt Lake City, Utah.

Enzo,

Yes, I understand the reason for the confusion. It's probably because Onkyo doesn't list the crossover values found by MultEQ.

If you turn Double Bass On then the main speakers that are set to Full Band and the sub receive the signal below the crossover frequency that MultEQ found. This can be a problem for speakers that are not capable of playing the lowest frequencies that should really only be going to the subwoofer. The Double Bass mode, in my opinion, is an "ego" mode that is intended for people who believe on faith that their loudspeakers are "large" and therefore capable of playing the lowest frequencies. If the speakers are truly "small" then they should be set to Small and Double Bass should be turned off. Ego should not get in the way of good sound!

Yes, I did look at your pictures. Nice house!

Best
Chris

So what you say is that even if the mains appears Full Band, Audyssey sets cross over values that will lowpass part of the mains signal to the sub. Then if one turns on the double bass, the signals are routed both to the sub and the mains, ignoring and defeating the cross over values set by Audyssey for the mains .

WOW! This is a revelation to me!!

Now I understand perfectly why letting the double bass on does not do any good to my sound!!!!

I agree EGO does not sound good!!!!

Thanks for the compliments on my house. Is not exactly what a Home Cinema should be, but I have to coop with it!!! Should you ever come to Milan, please let me know. I would be proud to show you how Audyssey sounds in my house and how my kitchen can prepare delicious food!!!

ciao

enzo

Chris:
What about the 4806ci? Does it have the high subwoofer resolution?