Re: Audyssey MultEQ: Questions and Answers - Onkyo, Denon, et. al.
Audyssey can make your system sound amazing if you set it up correctly. Unfortunately, the documents that come with the receivers are not written very well. There are a few things you can do to optimize your results.
Over at AVS there is an effort to create a better document (Chris from Audyssey participated in this). I got permission from the document's author to post it here.
Enjoy!
************************************************** *
Audyssey Setup – One Step at a Time
by (giomania at AVS)
The below step-by-step instructions are based on information collected from the Audyssey FAQ, located here:
Audyssey: Frequently Asked Questions and the AVS Forum Official Audyssey thread
Disclaimer: The following procedures may not work in all cases, as there are too many variables to account for in this document. If you feel further assistance is required, please ask your questions in this thread.
I. Room Setup
A.Lower the noise floor of the room (<45dBA) by turning off the HVAC system, projector, etc.
II. Microphone Setup
A.Use the microphone that came with the unit.
1.Use of a different microphone will cause incorrect frequency response measurements because of different internal calibration.
B.If you feel the urge to use another microphone, re-read section A.
C.Mount the microphone on a tripod.
D.Point the microphone at the ceiling.
E.Place the microphone at ear height when seated.
F.If the seat back is higher than your head, ensure the microphone is above the seat back.
1.If the seat back is a few inches behind the microphone, this will cause additional reflections.
G.Place the microphone in the primary listening position for the first measurement.
1.Audyssey uses this measurement to set the speaker distances and levels, so the microphone should be placed in the seating position used the most.
III. Subwoofer Setup
A.Determine the optimal placement of the subwoofer within your room using common accepted practices. (location, location, location)
1.Here are some useful references for subwoofer setup:
a.Audioholics subwoofer placement article:
Subwoofer Placement - The Place for Bass Part 1 — Reviews and News from Audioholics
b.Harman multiple subwoofer placement white paper:
http://www.harman.com/wp/pdf/multsubs.pdf
B.Disable the Low-Pass Filter (LPF) on the subwoofer, if allowed.
1.Disabling the LPF will result in more accurate subwoofer distance measurements.
2.If the LPF cannot be disabled, set it to the highest frequency allowed.
C.Ensure the subwoofer(s) are at least 3 – 5 inches (7 – 13 cm) from the wall.
1.Reverberating walls may result in inaccurate subwoofer distance measurements.
D.Set the subwoofer polarization (0 or 180 degrees) using common accepted practices.
1.If you have two subwoofers, ensure their polarization settings are the same.
E.If the subwoofer has a phase control (in addition to the polarization control), set it at “0”
1.Phase controls on subwoofers apply "delay" at one frequency rather than the needed group delay that is frequency independent. So, it is best to just leave them at “0”.
F.If the sub has an EQ system, use it to tame large peaks before calibrating with Audyssey.
1.Narrow peaks or dips in the response below 100 Hz that are 1/3 or 1/6 of an octave wide can be improved—but not eliminated—by Audyssey Mult EQ XT.
a.In these situations, the built-in subwoofer EQ systems might be useful.
2.Velodyne’s SMS and JL Audio’s ARO are two examples of EQ systems.
G.Calibrate the subwoofer volume
1.Set the volume control on the subwoofer at the middle of the adjustment range allowed.
a.Please note this “starting point” may not work with all subwoofers.
2.Place the microphone at the primary listening position (the center of the listening area) and run through the calibration process for the first measurement—until all speakers have been measured once.
3.After the first measurement process is complete, select "Calculate", then "Save" or "Store", then go to "Check Parameters".
a.Audyssey will calculate the speaker distances and trim levels from this first measurement.
b.Each manufacturer has a slightly different interface, so the terminology may not exactly match.
4.Check the subwoofer trim levels in the receiver / processor menu.
a.If the subwoofers trim level is at the maximum limit of the cut or boost adjustment range allowed, you need to adjust the volume control on the subwoofer and repeat step #2. Specific instructions will follow.
b.For example, Denon receivers have a trim adjustment range from -12dB to +12dB.
c.Trim adjustments are a tool used to achieve the goal of producing a specific SPL from each speaker / subwoofer when the system is played at reference level.
5.If the subwoofer trim level is at the maximum boost, turn up the subwoofer volume a bit and repeat step #2
6.If the subwoofer trim level is at the maximum cut, turn down the subwoofer volume a bit and repeat step #2
7.A suggestion for tweakers is to set the subwoofer trim level in the range of ±3 dB.
a.This is only a suggestion for the tweaker who likes to play around.
b.Audyssey’s position is to perform steps 4 to 6 above.
•Note: This process is for checking the trim levels only. After you have completed the subwoofer setup, be sure to start the measurement process over, following the guidance in section V to use all six or eight measurement positions available.
IV. Dual mono (LFE) Subwoofer Setup
A.Place the subwoofers symmetrically within the room, if at all possible.
B.Place the subwoofers at identical distances from the primary listening position, if at all possible.
1.When two subwoofers are driven as one unit, proper time alignment is critical.
2.The two subwoofers will not be properly time aligned unless they have the same physical distance from the primary listening position.
3.Adjusting the physical distance of the two subs effectively adjusts their time delay.
C.The above advice applies only to sealed rectangular rooms without any openings.
D.As an alternative to locating the subs at equal distances from the main listening position, you may insert an electronic device between the receiver / processor and the nearest subwoofer.
1.This device should introduce a time delay such that its output sound reaches the main listening position at the same time as the farthest subwoofer.
E.Attempt to match the output level of both subwoofers.
1.Play the receiver / processor internal LFE test tone while adjusting the volume control on the subwoofer.
2.Turn on one subwoofer and adjust the output level using an SPL meter to 80 decibels.
a.If you do not have an SPL meter, adjust the level by ear.
3.Turn off the first subwoofer, turn on the second subwoofer, and repeat the procedure.
4.Turn on both subwoofers and calibrate with Audyssey.
F.Follow the steps in subwoofer setup (above) for each subwoofer.
V. Microphone Placement (Measurement Positions)
A.Use the maximum amount of measurement positions allowed by the Audyssey version.
1.If you are using MultEQ or MultEQ XT you should use all six or eight measurement positions available.
B.Avoid taking measurements too far off to the side and/or outside the front Left and Right loudspeakers, even if seats are located there.
1.Frequency response in these locations will exhibit reduced high frequencies.
2.Audyssey would adjust the room correction filters according to this measured response, resulting in unnecessary compensation.
C.Avoid taking measurements too close to the back wall, even if the only seating is located there.
1.Move the microphone at least 1 foot (30 cm) from the back wall before measuring.
D.Audyssey uses the first measurement point to calculate the distances of each speaker and subwoofer. Distance measurements are really time measurements that ensure temporal coherence. It is a critical part of calibration because—without it—you have frequencies arriving at different times: This is called non-constant group delay, and is a form of distortion. The distances are calculated so the sounds from all speakers and subwoofers arrive at the first measurement position at the same time.
E.When calibrating only a primary listening position, use the following placement methodology:
1.The first microphone position (#1) must always be in the center of the listening area.
2.For measurement #2, move the microphone two feet (60cm) to the left of position #1.
3.For measurement #3, move the microphone two feet (60cm) to the right of position #1
4.For measurement #4, move the microphone two feet (60cm) forward of position #1.
5.For measurement #5, move the microphone two feet (60cm) forward of position #2.
6.For measurement #6, move the microphone two feet (60cm) forward of position #3.
7.For measurement #7, move the microphone one foot (30cm) to the left of position #1, and one foot (30cm) forward of the line formed by measurements #1, #2, and #3.
8.For measurement #8, move the microphone one foot (30cm) to the right of position #1, and one foot (30cm) forward of the line formed by measurements #1, #2, and #3.
F.Here is a visualization of eight measurements surrounding the primary listening position.
1.The first microphone position (#1) is where the silhouette of the head is located.
2.After the first measurement, the order in which you make the measurements does not matter. The order in the steps above only serves to ensure each location is measured.
3.The below diagram shows the optimum microphone placement for a typical living room. In general, Audyssey does not recommend putting the microphone in "every seat", except in a dedicated theater with seat rows.
4.In typical living rooms, placing the microphone in every seat will not give you the best results because the seats can be off axis or close to the wall. Audyssey recommends following a pattern close to what is in the diagram even if you only have one listening position. The most common problem with EQ systems is that they base their data collection on a single point in the room and that usually results in very poor performance.
VI. During Calibration
A.Do not make any sudden noises during the “chirp” measurements.
a.Audyssey measures for a few milliseconds (ms) after each “chirp” is finished, but then has to wait for the DSP to calculate, so the microphone is not active until a few ms before the next set of chirps.
B.Do not stand in between the speaker and the microphone or anywhere that the sound is either reflected off of you or absorbed by you.
1.The natural room acoustics must not be substantially affected.
C.Be prepared for the “chirp” measurements, as they are quite loud, and can startle you.
D.If a phase warning is shown, check the speaker wiring, and press “Skip” to continue with the calibration.
VII. After Calibration
A.Raise the speaker crossover settings, if desired.
1.Raising the crossover frequency from the calibrated setting does not affect the channel correction implemented by Audyssey.
2.Lowering the crossover frequency from the calibrated setting is not recommended.
a.Audyssey will not provide correction to the satellite speakers lower than the frequency it measures as the -3 dB point.
3.Setting the speakers to “Small” with a 60 Hz – 80 Hz crossover is a good starting point, assuming the calibrated crossover setting is 60 Hz or lower.
4.For additional details about the speaker setting process, see “Note 1” below.
B.Raise the low-pass filter setting (usually incorrectly identified as a crossover) of the LFE subwoofer in the receiver / processor to 120Hz, if allowed.
C.If the satellite speaker distance settings (excluding the subwoofer) were not measured accurately, and are markedly different from what you get with a tape measure, start all over.
1.Incorrect distance measurements for the satellite speakers indicate a procedural error, and the associated EQ results are likely to be poor.
D.Do not change the distance setting of the subwoofer.
1.Inaccurate subwoofer distance settings are the result of measured delays between the time when the receiver outputs the test tone and it is received at the microphone.
a.Any filters and/or active circuitry in subwoofers can delay this signal.
b.Audyssey simply measures the time delay and compensates for differences in the arrival time of sound from the various speakers and the subwoofer. It is best to compensate for these differences regardless of why they occur.
2.The subwoofer / satellite speaker time alignment blend is based on this measurement.
3.Inaccurate subwoofer distance measurements usually occur when the subwoofer’s Low-Pass Filter (LPF) is not disabled.
a.The LPF, by nature of its design, introduces additional delay to the signal; Audyssey detects and corrects for this delay.
E.Disable any Night Modes, DRC (Dynamic Range Compression), and D. Comp (Dynamic Compression) in the receiver / processor as well as the DVD / BD player.
1.If these features are not disabled, they could possibly cause adverse interaction with Dynamic EQ and Dynamic Volume.
2.You may need to temporarily turn off MultEQ to access these parameters in your receiver / processor.
3.You may also need to select a specific soundtrack type before a given parameter will appear in the menu for adjustment; check the manual to be certain.
F.If your receiver / processor has the THX Loudness Plus feature, turn it off if you plan to use Dynamic Volume.
G.Select one of the target curves created by Audyssey.
1.In a THX system, the “Flat” curve should be used when THX post-processing is on, and the “Reference” curve should be used when THX post-processing is off.
2.In other systems, the “Audyssey” curve should be used for listening to movies, and the “Flat” curve should be used for listening to music.
H.If desired, trim adjustments can be made in the receiver / processor, so that all speakers measure at 75 dB with an SPL meter (set at “C” and “Slow”) using the internal test tones. See “Note 2” below.
1.Audyssey will monitor these changes.
2.The changes are monitored so that Audyssey and its features (Room correction curves, Dynamic EQ and Dynamic Volume, etc.) work as designed.
3.If you were to make changes to the settings on a subwoofer, Audyssey would have no knowledge of this, and those features would not operate as designed.
Note 1: Audyssey does not set the crossovers; it simply measures the -3dB frequency point of each speaker. This information is passed to the receiver / processor for calculation of the speaker settings and crossover points, if applicable. Unfortunately, Audyssey does not report the -3dB frequency point measured for each speaker. The only information available to you is whether or not the speaker was designated “Large” or “Small”, and any crossover point selected for “Small” speakers.
Receiver / processor manufacturers use a specific Frequency Decision Point (FDP) to classify speakers as “Large” (full-range) or “Small” (less than full-range). The selection of the FDP varies among manufacturers, and may be 40 Hz, 80 Hz, or another frequency. If the -3 dB frequency measured by Audyssey is below the FDP, the speaker is classified as “Large’. If the -3 dB frequency measured by Audyssey is above the FDP, the speaker is classified as “Small”, and a crossover frequency is selected.
Each receiver / processor has various crossover points from which to choose. Typically, the first crossover setting above the -3 dB point measured by Audyssey is chosen. For example: If your receiver has crossover settings of 40, 60, 80, 100 and 120 Hz, and the speaker is set to “Small” with an 80 Hz crossover, that is an indication the - 3dB point is somewhere between 60 and 80 Hz.
Note 2: Before adjusting the trim settings, please understand that producing a calibrated setting other than 75 dB SPL results in reference level being achieved with the master volume set to something other than “0”. Further, Audyssey microphones are specified with a ± 2 dB maximum sensitivity tolerance. So, in the worst case scenario, the Audyssey microphone would be 2 dB “off”, which is more accurate than most popular consumer-level SPL meters. Consumer-level SPL meters are usually very inaccurate when measuring subwoofers; you have been warned.
