UPDATE. I was able to get in e-mail contact with Chris Kyriakakis, Audyssey's Chief Technologies Officer and to my surprise, he actually got back to me which is more than I can say for Onkyo's customers support regarding this issue:
Here's our e-mail conversation so far:
On Aug 12, 2007, at 5:31 AM, Monkey GoD wrote:
I won't take too much of your time. I'm not really sure if this is the proper contact to be asking these questions, but if you can please give me your opinion or direct me to someone who might know the answer, I would appreciate it.
I'm an owner of an Onkyo 805 receiver. It is plagued by an audio delay problem. I've measured the delay to be 47-67ms (depending on what the speaker distances are, ranging from 0-30 feet). The only audio input that is not affected by this delay is the Multi-Channel inputs which are not subject to audio processing. I've tried calling Onkyo's customer support but they seem to be oblivious to the problem, which is why I thought contacting someone more technically minded such as yourself would give me better answers. I've also gone through a replacement receiver with the same problem
My question is if it is inherent in Audyssey MultEQ equipped receivers to introduce a small audio delay such as this that is not defeatable? I experience this delay even when i turn Audyssey off, turning off all processing, and turning down the lip-sync setting on the receiver. I am unsure if this is an issue with Audyssey or just Onkyo's implementation of it. Again, If you can please give me your opinion or direct me to someone who might know the answer, I would appreciate it.
Chris Kyriakakis wrote:
Any DSP processing will be subject to some amount of delay. This is determined by the DSP manufacturer to ensure that processing on incoming audio signals can be performed seamlessly. They set what is called a "block" or "frame" size and that is some number of samples deemed appropriate by the DSP manufacturer. The benefit of having a fixed block size is that the delay through the system is constant. That means it's the same regardless of what processes are running (Dolby, DTS, Audyssey, bass management, etc.).
So, this is not inherent in Audyssey-equipped receivers. It is inherent in all DSP products. Audyssey and any of the other digital processes do not add any additional delay to what the fixed block processing delay already is.
How are you measuring the delays through the 805? 47 ms seems higher than what I would expect and if you set the speaker distance to 30 ft, you should get 77 ms not 67 ms. In any case, these numbers seem high. Are you sure there is no lip-sync delay set? These receivers let you adjust that to match the delay in the video that is caused by all of the digital displays.
I will ask the Onkyo engineers that we work with and let you know what I hear back from them about this.
Chris Kyriakakis, PhD
Founder and Chief Technical Officer
On Aug 13, 2007, at 10:26 AM, Monkey GoD wrote:
I measured the sound by attaching a microphone to my computer. My computer is connected through digital coaxial to the receiver.
I held the microphone a foot away from the main spkrs and just tapped on the microphone with my finger. When i do this, i am recording own finger tapping the microphone and then the resulting echo i get when it comes out of the speaker. I measured the distance between the waveforms of these two taps. The result i got was a delay of 47ms when the spkr distances is set to 30 feet, and a delay of 76ms when the spkr distances are set to 0 feet. (I said 67ms before, but that was a typo in my last email.). These measurements are not exact, but give a rough measurement of this delay. I have an old 8 year old Onkyo that I have ran these tests on the same way and it not suffer this delay and was immeasurable using my method of testing.
The receiver does have a lip-sync adjustment that adjust audio delays which I have already turned down to 0 ms when i measured the audio delay. I have also measured this in Onkyo's "Pure Audio" mode, which supposedly minimizes any processing done to the audio signal. The result is the same. The Multi-channel analog inputs on the receiver seem to be the only input on the receiver that does not suffer this delay.
I know that there is some amount of delay with all DSP processing systems. However, this delay should not be noticeable to the human ear. The problem is that is that a delay of 46-76ms noticeable in some instances, which is especially noticeable in interactive activities such as karaoke or video gaming in which the audio is synced with your actions. It also exaggerates any delays that also exist in some digital broadcast channels.
I appreciate greatly your efforts and hope that you are able to find more than I did from Onkyo about this apparent problem.