If you used measurements in your Denon or Marantz to set up speaker distances, speaker timing is off, and if your speakers are not equidistant, sound can be noticeably off. There's a fix.
TL/ DR - Denon and Marantz used the wrong calculation for the speed of sound, which screws up Atmos and multichannel. It's fixed in latest receivers. For everyone else, switching your speaker distances to meters and multiplying the distances by .874 will adjust the sound travel calculation back to 343 m/s vs the 300 m/s they used.
I have confirmed that timing gets incredibly close in REW and it's impressive.
Background:
Sound United support confirmed a longstanding bug with Denon and Marantz receivers and speaker distance calculations. It's fixed in the 2023 and later gear, but for the rest of us, I'll walk through the problem, how to verify it, and how to address it.
I can't take credit for this find- the folks over at AVS forum found it and have been discussing it for a while.
https://www.avsforum.com/threads/au...ff-according-to-rew-impluse-readings.3243684/
Background: Atmos at home has been good, but it always sounded a little echoey/muddy, which I thought might be an artifact of recreating a theater environment. I ran across an article where someone ran Room EQ Wizard (REW) and discovered the timing of signal to the listerner was inaccurate if all your speakers are not equidistant to the main listening position (MLP). Mathematically, they found out that all the speakers were off because the constant used for the speed of sound was 300 m/s vs 343 m/s. Multiplying your speaker distance by .874 (as sound is traveling faster than the receiver thinks) fixes the issue in older receivers.
So if you used measurements in your Denon or Marantz to set up speaker distances, your speaker timing is off...
and if ALL your speakers are not equidistant to the listener, playback timing can be noticeably off, speaker to speaker.
Fix- I remeasured my speaker distances against my mlp, getting them as close as possible and confirming with a tape measure.
I adjusted all distances by multiplying .874
Result- Noticeable improvement. I'm going to re run REW this week and see if I can adjust even more, but the playback is tight and consistent between the front, back and height speakers.
Try it- you can write down all your original distances. Adjust them and see if it sounds better.
Now I need to do the upstairs Atmos setup!
Edit- issue is not Audyssey, but in Denon and Marantz speaker distance calculations- Audyssey just get applied against what is calculated in the AVR.
TL/ DR - Denon and Marantz used the wrong calculation for the speed of sound, which screws up Atmos and multichannel. It's fixed in latest receivers. For everyone else, switching your speaker distances to meters and multiplying the distances by .874 will adjust the sound travel calculation back to 343 m/s vs the 300 m/s they used.
I have confirmed that timing gets incredibly close in REW and it's impressive.
Background:
Sound United support confirmed a longstanding bug with Denon and Marantz receivers and speaker distance calculations. It's fixed in the 2023 and later gear, but for the rest of us, I'll walk through the problem, how to verify it, and how to address it.
I can't take credit for this find- the folks over at AVS forum found it and have been discussing it for a while.
https://www.avsforum.com/threads/au...ff-according-to-rew-impluse-readings.3243684/
Background: Atmos at home has been good, but it always sounded a little echoey/muddy, which I thought might be an artifact of recreating a theater environment. I ran across an article where someone ran Room EQ Wizard (REW) and discovered the timing of signal to the listerner was inaccurate if all your speakers are not equidistant to the main listening position (MLP). Mathematically, they found out that all the speakers were off because the constant used for the speed of sound was 300 m/s vs 343 m/s. Multiplying your speaker distance by .874 (as sound is traveling faster than the receiver thinks) fixes the issue in older receivers.
So if you used measurements in your Denon or Marantz to set up speaker distances, your speaker timing is off...
and if ALL your speakers are not equidistant to the listener, playback timing can be noticeably off, speaker to speaker.
Fix- I remeasured my speaker distances against my mlp, getting them as close as possible and confirming with a tape measure.
I adjusted all distances by multiplying .874
Result- Noticeable improvement. I'm going to re run REW this week and see if I can adjust even more, but the playback is tight and consistent between the front, back and height speakers.
Try it- you can write down all your original distances. Adjust them and see if it sounds better.
Now I need to do the upstairs Atmos setup!
Edit- issue is not Audyssey, but in Denon and Marantz speaker distance calculations- Audyssey just get applied against what is calculated in the AVR.
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