Audyssey MultEQ
The biggest part of what MultEQ is calibrating is the frequency response of the speaker. It tries to undo the problems that are added by the room. They come from standing waves and reflections from the walls, floor, etc.
The Audyssey Reference target curve is flat in the bass with rolloff in the high frequencies that starts at 4kHz
and goes down gently at 10 kHz and then slightly steeper after that to 20 kHz
It also calculates the proper delays for the speakers, displayed as distances, so that sound from all speakers arrives at the same time at the first measurement position.
It is also the reason that many complain that the sub is found to be at the "wrong" distance.
What they forget is that the signal from the sub is delayed by the electrical filters in the sub (the low pass filters that can't be turned off), as well as the physical distance to the listener. The correction must include both.
If you want to use an SPL meter to measure the speaker levels, then you must make sure that MultEQ is ON and Dynamic EQ is OFF.
Or you can leave them both on and turn the volume to 0 because Dynamic EQ is inactive at that volume.
Audyssey Dynamic EQ
Addresses human hearing changes as the volume is lowered.
The first thing that diminishes at lower volumes is our perception of bass,
so Dynamic EQ boosts it according to a set of curves that match human perception.
The second thing that changes is our perception of surround impression,
so Dynamic EQ boosts the surround level as you lower the volume.
The idea with Dynamic EQ is to turn the volume down to where you like it and it will adjust the response
and surround envelopment for you. It's made for listening at softer, not loud, levels.
Audyssey Dynamic Volume
For the past several years, receivers have included a dynamic range compression method called Night Mode and now DRC for TruHD content.
It is supposed to solve the problem of content getting too loud, but it has failed to do so for a number of reasons including
wrong setting of the flags during production, inability of the method to adjust the reaction time,
and no capability for perceptual loudness correction when the volume is turned down.
Audyssey Dynamic Volume was designed to address the problems described above and
with its ability to look ahead it can vary the reaction time to increases in loudness so that no artifacts are heard.
Dynamic Volume is designed around a known quantity: dialog level in film. The idea is that the user should set the level for the dialog volume they want. Then, depending on the range you have selected (Light, Heavy), Dynamic Volume will keep the loudest and softest sounds within that range.
The idea is not to squash everything to one volume level. You still want to know that some things are louder than others, but that they stay within an acceptable range.
Audyssey allow some customization in the Dynamic Volume settings because this is a preference. Denon decided on three modes (Midnight/Evening/Day), Onkyo has two (Heavy/Light). Light is very close to Day and Heavy is very close to Midnight.
Dynamic Vol (Light) prevents loud and soft sounds from being much louder and softer respectively than average sounds.
Dynamic Vol (Heavy) affects volume the most, causing all sounds to be of equal loudness.
THX Loudness Plus vs Audyssey Dynamic EQ
Roughly speaking Audyssey Dynamic EQ and THX Loudness Plus is attempting to solve the same thing:
http://www.thx.com/technologies/loudness_plus.html
THX Loudness Plus compensates for the tonal and spatial shifts that occur when the volume level is reduced. By automatically raising the levels of the ambient sound, you experience the true impact of movies, music and games regardless of the volume setting.
http://www.audyssey.com/technology/dynamicEQ.html
Audyssey Dynamic EQ is the first loudness correction technology to solve the problem of deteriorating sound quality as volume is decreased by taking into account human perception and room acoustics.
Audyssey Dynamic EQ selects the correct frequency response and surround volume levels moment-by-moment. The result is something never before possiblebass response, octave-to-octave balance and surround impression that remain as they should be despite changes in volume. This is the first technology to carefully combine information from incoming source levels with actual output sound levels in the room, a pre-requisite for delivering a loudness correction solution
The manual and the Onkyo implementation in the menus is extremely confusing.
THX Loudness Plus and Audyssey Dynamic EQ/Dynamic Volume can't be on at the same time because they would interfere with each other.
The Preserve THX selection is Onkyo's way of letting you engage THX for everything except loudness correction.
Preserve THX settings: No -> Audyssey Dynamic EQ / Audyssey Dynamic Volume will be active in THX listening mode depending on the setting.
This setting is only available if Loudness Plus is set to Off
Audyssey Technologies in Onkyo models:
TX-NR906 and TX-SR876 :
MultEQ XT, Dynamic EQ and
Dynamic Volume
TX-SR806 and TX-SR706 :
MultEQ and
Dynamic EQ
TX-SR606 :
2EQ and
Dynamic EQ
[regarding using a SPL meter]
Please understand that it is physically impossible to use an SPL meter (of any brand) and sinusoidal test tones and hope to determine anything about frequency response. That method has no chance. You will not even be in the ballpark. The reason is that sinusoidal tones in a room suffer from standing waves. Just try moving the meter 6" while playing a sine wave and look at the needle. It can move by 10 dB or more.
Making changes to the EQ based on SPL meter measurement with CD tones is like shooting at flies in the dark.
(Also see end of the paragraph about
Audyssey MultEQ)
See later for THX Re-Eq/Audyssey Roll-Off
Facebook
Twitter