Figuring out proper surround delay.

[JOHN FICKEL]

I realize in all of the AVRS today and processors they automatically figure out (surround delay ) with importing the proper distance setting for all your speakers. However I would really like to know if one had to figure it out manually how would you do that. My left main is 11.2 ft. My right main is 12.1ft My center is 11.6 ft and my left surround is 8.2 ft and right surround is 11.4. Ft I was just curious what my proper surround delay would be. Thank you !!

 

[TLS Guy]

The only thing you can do is measure the distance and then calculate the time it takes to get from the speaker to your preferred listening position taking the speed of sound to 1100 ft/sec.

It won't be correct though, as speakers have phase shifts in their crossovers. Phase shifts are just another way of expressing time shifts. In addition there are group delays associated with speaker loading.

In the bass department, because of the long wave lengths, the difference between using measured distance and the true result can be, and usually is enormous.

People often report here huge discrepancies between Audyssey and measured, and don't believe the result and override it manually. However the distance/delay is something that Aydyssey is very good at getting right.

So if you want to calculate it then you need intimate knowledge of the crossovers on your speakers, including subs, and details of time delays associated with port loading etc. As you know loudspeaker manufacturers tell you little of anything useful about their speakers, and do everything to obfiscate as rule, as they don't want you to know how lousy their speakers really are.

 

[William Lemmerhirt]

To add to tlsguys post. The reason audyssey usually gets it right, is because it sees the room in an auditory sense. People see with their eyes first, so when audyssey posts distances that are different than what we see visually, we instinctively thing audyssey is wrong. In reality audyssey see with its ears, and calculates distance based on how long it takes to hear the test tones after it sends them. We see line of sight but audyssey sees sound after bouncing off of furniture, and being absorbed by carpet and being diffused by any number of things in the room. That's also how we hear it with our ears. I'm sure there's an easy way to do it, but my brain cell will trust audyssey for now. Imperfect as she is.

 

[STC]

To OP, Manually, I use stereo track with regular single beat. For AV set the processor to play all channel; And manually adjust the delay until the timing difference is no longer perceivable.

The other method is to use REW room EQ but now I mainly use the above method as it involves to many speakers in my setup.

p.s. I love you setup arrangement. That's what I wanted to do with my system but just didn't have the space. Congrats!

 

[JOHN FICKEL]

Ok thank you !!