**miniDSP DDRC-88A Official Thread**8-channel AI/AO Dirac Live in a box - Page 385 - AVS Forum | Home Theater Discussions And Reviews
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post #11521 of 16634 Old 08-29-2016, 03:34 PM
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With the recent discussion regarding setting Dirac output levels when some speakers have higher sensitivity than others, I am suggesting that my "Calibration Guide" be modified as follows.

Current wording:

- One-by-one, click the output button for each of the other speaker channels and observe the output level. It should be very close to -12, like the left channel +/- 2. Small variations in output are not significant. Large variations indicate something is wrong with the gain setting for that channel, and the calibration should be stopped until the gain issue is resolved.

Proposed wording:

- One-by-one, click the output button for each of the other speaker channels and observe the output level. It should be very close to -12, like the left channel +/- 2. Small variations in output are not significant. Large variations could indicate one of several conditions:

a). Something might be wrong with the gain setting for that channel. Research gain settings for the 88A to make sure the settings are correct for your configuration.
b). You may have significant sensitivity differences across your speakers. In a recent example posted in the 88A thread, a user reported main speakers with 104dB sensitivity, and surround speakers with 94dB sensitivity. This large difference made it impossible to set the appropriate output level without using the individual channel level sliders. See the note below for more details.

Note: In the case of significant sensitivity differences among speakers, try this approach to set the output levels properly:
1. Identify the speaker with the lowest sensitivity.
2. Output the test tone for that speaker and adjust the master output level slider until the level is exactly -12.
3. Now go to the speaker with the highest sensitivity and output the test tone. The level indicator will be significantly higher than -12.
4. Using the channel level slider for that channel, adjust the speaker-specific output level lower until it reaches -12.
5. Continue this process until all speakers, both the low sensitivity and the high sensitivity ones, are measuring -12.
6. Note that the sub channel should also measure -12, which you should be able to achieve without using the individual sub channel output slider (adjust the sub’s gain instead).
7. Now you can continue with the Dirac measurements, and your resulting calibration should be good.


Did I capture it correctly? Other comments?
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post #11522 of 16634 Old 08-29-2016, 04:22 PM
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Quote:
Originally Posted by AustinJerry View Post

Note: In the case of significant sensitivity differences among speakers, try this approach to set the output levels properly:
1. Identify the speaker with the lowest sensitivity.
2. Output the test tone for that speaker and adjust the master output level slider until the level is exactly -12.
3. Now go to the speaker with the highest sensitivity and output the test tone. The level indicator will be significantly higher than -12.
4. Using the channel level slider for that channel, adjust the speaker-specific output level lower until it reaches -12.
5. Continue this process until all speakers, both the low sensitivity and the high sensitivity ones, are measuring -12.
6. Note that the sub channel should also measure -12, which you should be able to achieve without using the individual sub channel output slider (adjust the sub’s gain instead).
7. Now you can continue with the Dirac measurements, and your resulting calibration should be good.


Did I capture it correctly? Other comments?

This ^ is exactly how I did it because my center is 105 ish sensitive and my mains are 95. My surrounds are supposed to be 93, but are quite a bit lower than that compared to my mains and center.
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post #11523 of 16634 Old 08-29-2016, 06:29 PM
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Originally Posted by AustinJerry View Post
However, if you click the bubble on the slider, the indicators immediately show the correct level value. So, minor bug, not major show stopper, IMO.
I think this is true nowadays.

It used to be worse, IIRC, in that both the slider and the numeric display was wrong. (Or maybe this is long enough ago that the numeric display wasn't there yet?)

I think it was also worse in another way. The levels weren't showing correctly graphically, but test tones worked fine (since they were where you had left them from a previous run), but, (again, from memory, and it has been a while!) it seemed like the resulting calibration was off completely in that it now thought that the level trims were 0 (since I didn't move them), and the channel to channel balance was all messed up in the end. [now that I type this, I'm forced to wonder if this is what started the entire "don't touch the individual channel sliders!" recommendation].

Anyway, it has gotten better, and I always do the tweak to make sure that the UI is representing reality because it has become habit.
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post #11524 of 16634 Old 08-29-2016, 06:36 PM
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Quote:
Originally Posted by AustinJerry View Post

Note: In the case of significant sensitivity differences among speakers, try this approach to set the output levels properly:
1. Identify the speaker with the lowest sensitivity.
2. Output the test tone for that speaker and adjust the master output level slider until the level is exactly -12.
3. Now go to the speaker with the highest sensitivity and output the test tone. The level indicator will be significantly higher than -12.
4. Using the channel level slider for that channel, adjust the speaker-specific output level lower until it reaches -12.
5. Continue this process until all speakers, both the low sensitivity and the high sensitivity ones, are measuring -12.
6. Note that the sub channel should also measure -12, which you should be able to achieve without using the individual sub channel output slider (adjust the sub’s gain instead).
7. Now you can continue with the Dirac measurements, and your resulting calibration should be good.


Did I capture it correctly? Other comments?
I think you should make it more general. It isn't necessarily a speaker sensitivity issue. It could be:
a) speaker sensitivity
b) mismatched amplifiers (I started this with an ADCOM 2535 [60 WPC] running my surrounds, and a Sunfire Cinema Grand Signature running my front sound stage [405 WPC]. [I've since replaced the Adcom with a 7 channel Sunfire]
c) speaker distance from the MLP [My right surround is furthest from the MLP]
d) ALL OF THE ABOVE

Maybe something along the lines of "In the case of significant output differences among speakers..." (?)
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post #11525 of 16634 Old 08-29-2016, 09:06 PM
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Originally Posted by KevinG View Post
I think this is true nowadays.

It used to be worse, IIRC, in that both the slider and the numeric display was wrong. (Or maybe this is long enough ago that the numeric display wasn't there yet?)

I think it was also worse in another way. The levels weren't showing correctly graphically, but test tones worked fine (since they were where you had left them from a previous run), but, (again, from memory, and it has been a while!) it seemed like the resulting calibration was off completely in that it now thought that the level trims were 0 (since I didn't move them), and the channel to channel balance was all messed up in the end. [now that I type this, I'm forced to wonder if this is what started the entire "don't touch the individual channel sliders!" recommendation].

Anyway, it has gotten better, and I always do the tweak to make sure that the UI is representing reality because it has become habit.

It is exactly what happens to me.

Austin Jerry: your update of the guide is correct. I did exactly that: choosing the lower channel, rise the volume to -12 and adjust the others with thie slider. Thank you

My system 5.1 :ROTEL RSX-1562 /Fronts: B & W 804 D2; surround : B&W 704 and center B&W HTM4d2 /sub SVS PC 2000 / TV Samsung UN55ES8000
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post #11526 of 16634 Old 08-30-2016, 06:10 AM
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Originally Posted by KevinG View Post
I think you should make it more general. It isn't necessarily a speaker sensitivity issue. It could be:
a) speaker sensitivity
b) mismatched amplifiers (I started this with an ADCOM 2535 [60 WPC] running my surrounds, and a Sunfire Cinema Grand Signature running my front sound stage [405 WPC]. [I've since replaced the Adcom with a 7 channel Sunfire]
c) speaker distance from the MLP [My right surround is furthest from the MLP]
d) ALL OF THE ABOVE

Maybe something along the lines of "In the case of significant output differences among speakers..." (?)
Thanks for the feedback, Kevin. I'll modify the wording so that it reflects the other situations in which the modified procedure might be applicable.
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post #11527 of 16634 Old 08-30-2016, 09:21 AM
 
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Originally Posted by AustinJerry View Post
With the recent discussion regarding setting Dirac output levels when some speakers have higher sensitivity than others, I am suggesting that my "Calibration Guide" be modified as follows.


Proposed wording:




6. Note that the sub channel should also measure -12, which you should be able to achieve without using the individual sub channel output slider (adjust the sub’s gain instead).



Did I capture it correctly? Other comments?
Why does the sub channel has to be at -12 using sub gain? Why not match the sub with highest of the speakers and then use the individual volume knob to bring sub to -12 just like we did for highest sensitive speaker? What would be the difference b/w the two ways to match the sub?
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post #11528 of 16634 Old 08-30-2016, 09:32 AM
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Originally Posted by filya View Post
Why does the sub channel has to be at -12 using sub gain? Why not match the sub with highest of the speakers and then use the individual volume knob to bring sub to -12 just like we did for highest sensitive speaker? What would be the difference b/w the two ways to match the sub?
I am not sure that one approach is better than the other. They might produce similar or the same results. I wrote it the way I did for philosophical reasons. For a component that has a gain control, whether it is a powered sub or a power amp, my approach would be to use the external gain to achieve the proper output levels in DLCT. IOW, if I can avoid using the individual channel level sliders, then I will.

So as a homework assignment for you, why don't you try both approaches, measure the results using REW, and report back to us whether the two approaches are identical, or that one is better than the other?
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post #11529 of 16634 Old 08-30-2016, 09:54 AM
 
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Originally Posted by AustinJerry View Post
I am not sure that one approach is better than the other. They might produce similar or the same results. I wrote it the way I did for philosophical reasons. For a component that has a gain control, whether it is a powered sub or a power amp, my approach would be to use the external gain to achieve the proper output levels in DLCT. IOW, if I can avoid using the individual channel level sliders, then I will.

So as a homework assignment for you, why don't you try both approaches, measure the results using REW, and report back to us whether the two approaches are identical, or that one is better than the other?
I did both and in terms of FR, they came same based on how curve was designed. I don't think FR will be of much help here. The difference I found was that the sub seemed to produce cleaner bass and didn't bottom out when was match with highest sensitivity speaker. When I had sub at -12 using sub gain, I played San Andreas and in certain bass heavy scenes I felt like it was bloating out. So then I calibrated with subs matching with mains and it was fine. Of course this is subjective and also depends on how well the subs are in terms of headroom. Mine are dual opposing 18" drivers subs so don't think they are the weak link here. I'll do the subjective listening one more time to compare and let you guys know.
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post #11530 of 16634 Old 08-30-2016, 10:03 AM
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Originally Posted by filya View Post
Why does the sub channel has to be at -12 using sub gain? Why not match the sub with highest of the speakers and then use the individual volume knob to bring sub to -12 just like we did for highest sensitive speaker? What would be the difference b/w the two ways to match the sub?
Quote:
Originally Posted by filya View Post
I did both and in terms of FR, they came same based on how curve was designed. I don't think FR will be of much help here. The difference I found was that the sub seemed to produce cleaner bass and didn't bottom out when was match with highest sensitivity speaker. When I had sub at -12 using sub gain, I played San Andreas and in certain bass heavy scenes I felt like it was bloating out. So then I calibrated with subs matching with mains and it was fine. Of course this is subjective and also depends on how well the subs are in terms of headroom. Mine are dual opposing 18" drivers subs so don't think they are the weak link here. I'll do the subjective listening one more time to compare and let you guys know.
Ultimately you should go with what sounds best. I cannot conduct the same test because all of my speakers are from the same manufacturer, with very close sensitivity ratings, so my levels in DLCT are essentially the same.
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post #11531 of 16634 Old 08-30-2016, 10:12 AM
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Originally Posted by filya View Post
Why does the sub channel has to be at -12 using sub gain? Why not match the sub with highest of the speakers and then use the individual volume knob to bring sub to -12 just like we did for highest sensitive speaker? What would be the difference b/w the two ways to match the sub?
Basically you want to maximize signal to noise ratio, i.e. maximizing gain without clipping any input.
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post #11532 of 16634 Old 08-30-2016, 12:25 PM
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Do I do the same thing and zero Audyssely line levels back to zero and then use REW post Audyssey to manually adjust the ceiling speakers to match the zeroed Dirac floor channels or is there a better way to do this? I hope what I am asking makes sense?
Welcome back! We knew you wouldn't be gone for long. ;-)

Just turn off Audyssey and leave the levels/distances that it measured intact. The distances will account for the DIRAC introduced delay, and the levels will account for channel differences (the DIRAC channels should all measure very closely to one another).
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post #11533 of 16634 Old 08-30-2016, 12:42 PM
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Thanks buddy, that makes it easy
After the recent discussions on how to successfully integrate two 88BM's into an Atmos configuration as well as bass manage multiple subs, I'm counting the days until you buy a second unit again. You know you want it...
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post #11534 of 16634 Old 08-30-2016, 12:58 PM
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Originally Posted by AustinJerry View Post
With the recent discussion regarding setting Dirac output levels when some speakers have higher sensitivity than others, I am suggesting that my "Calibration Guide" be modified as follows.

Current wording:

- One-by-one, click the output button for each of the other speaker channels and observe the output level. It should be very close to -12, like the left channel +/- 2. Small variations in output are not significant. Large variations indicate something is wrong with the gain setting for that channel, and the calibration should be stopped until the gain issue is resolved.

Proposed wording:

- One-by-one, click the output button for each of the other speaker channels and observe the output level. It should be very close to -12, like the left channel +/- 2. Small variations in output are not significant. Large variations could indicate one of several conditions:

a). Something might be wrong with the gain setting for that channel. Research gain settings for the 88A to make sure the settings are correct for your configuration.
b). You may have significant sensitivity differences across your speakers. In a recent example posted in the 88A thread, a user reported main speakers with 104dB sensitivity, and surround speakers with 94dB sensitivity. This large difference made it impossible to set the appropriate output level without using the individual channel level sliders. See the note below for more details.

Note: In the case of significant sensitivity differences among speakers, try this approach to set the output levels properly:
1. Identify the speaker with the lowest sensitivity.
2. Output the test tone for that speaker and adjust the master output level slider until the level is exactly -12.
3. Now go to the speaker with the highest sensitivity and output the test tone. The level indicator will be significantly higher than -12.
4. Using the channel level slider for that channel, adjust the speaker-specific output level lower until it reaches -12.
5. Continue this process until all speakers, both the low sensitivity and the high sensitivity ones, are measuring -12.
6. Note that the sub channel should also measure -12, which you should be able to achieve without using the individual sub channel output slider (adjust the sub’s gain instead).
7. Now you can continue with the Dirac measurements, and your resulting calibration should be good.


Did I capture it correctly? Other comments?
Quote:
Originally Posted by KevinG View Post
I think you should make it more general. It isn't necessarily a speaker sensitivity issue. It could be:
a) speaker sensitivity
b) mismatched amplifiers (I started this with an ADCOM 2535 [60 WPC] running my surrounds, and a Sunfire Cinema Grand Signature running my front sound stage [405 WPC]. [I've since replaced the Adcom with a 7 channel Sunfire]
c) speaker distance from the MLP [My right surround is furthest from the MLP]
d) ALL OF THE ABOVE

Maybe something along the lines of "In the case of significant output differences among speakers..." (?)
Would this methodology differ if you have a separate gain adjustment knob for each speaker channel? I currently have one bridged crown xls 1500 for each speaker with a gain knob to adjust the level. I typically do a test tone to my sub and set the master output level using this (typically that means at -50 and input gain all the way to the right +20). I then run test tone for each channel using the amp gain knob to adjust to get each speaker at -12 with all individual sliders not used (maxed).

All my levels end up @75db +-1dB.

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post #11535 of 16634 Old 08-30-2016, 01:15 PM
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Originally Posted by HTPCat View Post
Would this methodology differ if you have a separate gain adjustment knob for each speaker channel? I currently have one bridged crown xls 1500 for each speaker with a gain knob to adjust the level. I typically do a test tone to my sub and set the master output level using this (typically that means at -50 and input gain all the way to the right +20). I then run test tone for each channel using the amp gain knob to adjust to get each speaker at -12 with all individual sliders not used (maxed).

All my levels end up @75db +-1dB.
IMO, this would be the preferred method. The method described in the quote above assumes there are no external gain adjustments.
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post #11536 of 16634 Old 08-30-2016, 07:29 PM
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Added a section to my 88BM Guide (linked in my sig) titled "Using the 88BM in Immersive Sound (Atmos) Configurations".

The two approaches are the one suggested by @markus767 , and the one suggested by @KevinG . My thanks to Markus for the nice diagrams. I think I captured our conversations, but some proof-reading and feedback would be appreciated. It's important that we capture this information accurately, because the topic will come up again.
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post #11537 of 16634 Old 08-31-2016, 12:56 AM
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@AustinJerry , in either case there's an additional step: the two units need to be time aligned as they will introduce a varying amount of delay which depends on the DL calibration.

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post #11538 of 16634 Old 08-31-2016, 05:19 AM
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Originally Posted by markus767 View Post
@AustinJerry , in either case there's an additional step: the two units need to be time aligned as they will introduce a varying amount of delay which depends on the DL calibration.
Agree. Re-running Audyssey (or whatever) should do the trick, and remembering to turn it off after that, of course.

One other thing that will be different between the two suggested methods is the total delay introduced. In method one, with cascaded 88-As, you're up to 36ish ms of delay. In method two, you're down around 18ish ms. Why does this matter? I don't think there are any concerns with lip-sync (though someone with two cascaded units would have to let us know)...but, in my case, I'm using a couple of tactiles. These need quite a bit of delay to sync with the rest of the subs in the system (since they are nearfield, and instantaneous). I get "close enough" by using a 2x4, but I would have nowhere near enough delay if I had 2 cascaded 88a units.

By the way, it can't be said enough how fantastic it is that @AustinJerry provides these extremely well written guides. Thanks again!
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post #11539 of 16634 Old 08-31-2016, 05:20 AM
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@AustinJerry , in either case there's an additional step: the two units need to be time aligned as they will introduce a varying amount of delay which depends on the DL calibration.
That adds a complexity that I was not aware of (not being an Atmos user myself). Has there been a discussion here WRT how to time align two units? If not, could you provide some guidance? Otherwise, I should remove the new section.

@KevinG was typing his response at the same time. If the Audyssey approach is acceptable, can you provide just a little more detail on how to do it? Run Audyssey, then turn Audyssey RC off, leaving delays in the AVR intact?
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post #11540 of 16634 Old 08-31-2016, 05:51 AM
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Originally Posted by AustinJerry View Post
That adds a complexity that I was not aware of (not being an Atmos user myself). Has there been a discussion here WRT how to time align two units? If not, could you provide some guidance? Otherwise, I should remove the new section.

@KevinG was typing his response at the same time. If the Audyssey approach is acceptable, can you provide just a little more detail on how to do it? Run Audyssey, then turn Audyssey RC off, leaving delays in the AVR intact?
With my two units prior to BM install start.
Unit 1 ran 7.1. Audy put distances at 31.8-32.0. Second unit with just 4 Atmos resulted in distances of 25.3-25.4 in audy. Yea all audy is turned off and I always just kept levels and distances. Audy Levels on all channels were -4.5 despite which 88a.

My understanding is that variance in audy distances helps to account for the multi unit delay. All 7.x.4 are essential matched drivers with similar sensitivity of 95 or 98db.
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post #11541 of 16634 Old 08-31-2016, 06:10 AM
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I guess what I'm really saying is there's a 6.5' delay difference between 88A1 and 88A2 according to Audy distance settings. At 1130fps, that implies that the two 88A have about a 6ms delay difference between them. If my math is correct.
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post #11542 of 16634 Old 08-31-2016, 07:40 AM
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I guess what I'm really saying is there's a 6.5' delay difference between 88A1 and 88A2 according to Audy distance settings. At 1130fps, that implies that the two 88A have about a 6ms delay difference between them. If my math is correct.
Thanks for sharing your experience. I have some questions.

Based on the "Dirac" tab in the 88BM, we can now see the trims and delays that Dirac has set. And if you select a Config on the 88BM that has no Dirac project associated with it, the 88BM shows Dirac trims and delays to be zero (as expected).

So my question is: when you say you run Audyssey "prior to BM install start", what state is the 88BM in? Is Dirac on, or in bypass? Is the active memory slot one with a project loaded, or an empty memory slot? Or (better yet), did you restore the 88BM to factory defaults just to ensure a clean slate before running Audyssey?

And why would you leave Audyssey trims active (even though they may all be close to the same)?

Not understanding your math in the quote above. Where did you come up with 6.5'? As I understand it, the only way to tell whether there is a timing issue between two 88BM's would be to:

- Run Audyssey.
- Observe the delay for a particular speaker, say the center channel, when it is connected to 88BM no 1.
- Temporarily move the center channel to 88BM no 2.
- Re-run Audyssey.
- Observe the delay for the center channel and compare it to the delay calculated in the first run.
- Any difference will be the timing difference between the two pieces of hardware, which I would expect to be much smaller than 6ms.

And after everything was done, did you attempt to verify that speakers on one 88BM are indeed time-aligned to speakers on the other 88BM, using REW's impulse response measurements?

Sorry for all the questions, but this whole time-alignment issue is not as straight-forward as one might think.
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post #11543 of 16634 Old 08-31-2016, 07:50 AM
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Originally Posted by AustinJerry View Post
Sorry for all the questions, but this whole time-alignment issue is not as straight-forward as one might think.
I think he is saying that his first unit (before re-doing things to insert BM into the chain) showed an Audyssey measured distance of 31.8-32.0. for all channels. Then, he added the 2nd unit, running the heights, and, after that was done, Audyssey showed those speakers as being 25.3-25.4 feet away. One would expect that each unit would show the exact same (or close enough) distance for each channel on that 88a since Dirac should have already done delay trims for the MLP (which his does).

He's simply subtracting a rough approximation of each of those units to come up with an approximate difference of 6.5 feet (and backing out the delay from that distance in terms of ms). I don't know if this is an inherent difference in the two units, or a difference in time it takes to apply the specific corrections to the channels on each unit. It doesn't really matter. In the end, Audyssey will correct for the difference with it's own delays, and all should be well.
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post #11544 of 16634 Old 08-31-2016, 08:02 AM
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Here's an interesting(?) way of thinking about this problem.

Let's say you have 8 speakers. They are arranged exactly lined up in front of the MLP. The first one is 1 ft away, then 2nd one is another ft behind that one, and so on. Like dominos.

Speakers 1-4 are connected to 88a #1 , and speakers 5-8 are connected to 88a #2 .

You calibrate speakers 1-4, and dirac applies:
3 ft of delay to speaker #1 (because it has to match speaker #4 which is 3 ft further away)
2 ft of delay to speaker #2
1 ft of delay to speaker #3
0 ft of delay to speaker #4 (since it is the furthest one away)

You calibrate speakers 5-8, and dirac applies:
3 ft of delay to speaker #5 (becuase it has to match speaker #8 which is 3 ft further away)
2 ft of delay to speaker #6
1 ft of delay to speaker #7
0 ft of delay to speaker #8 (since it is the furthest one away)

Now you run Audyssey.
It sees speakers #1 -4 as arriving as 4 feet away, and it see speakers #5 -8 arriving as 8 feet away. And it applies the following delays:
4 ft of delay to speakers #1 -#4 (because it has to match the other speakers which are 4 ft away)
0 ft of delay to speakers #5 -#8 (because they are the furthest one away)

Now, all 8 speakers are time aligned to arrive at the same time as the furthest single speaker (#8 ).
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post #11545 of 16634 Old 08-31-2016, 08:16 AM
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Originally Posted by AustinJerry View Post
That adds a complexity that I was not aware of (not being an Atmos user myself). Has there been a discussion here WRT how to time align two units? If not, could you provide some guidance? Otherwise, I should remove the new section.
The most accurate way is to use REW with a timing reference comparing impulse response peaks.
A simpler solution would be to run Audyssey and look at the delays it finds.

By the way, DL in the 88A/BM does not work with Dolby Atmos-enabled speakers. It can't extract the correct delay but it does apply proper magnitude correction.

Markus

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post #11546 of 16634 Old 08-31-2016, 08:17 AM
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Correct. I have not ran Dirac calibrations with BM. It's installed and routed and matrixed but I need to hook up my 4 heights and run new cals. Right now my 7.3 is hooked up but all 0s since no time for dlct yet.

My previous post was specifically before BM was introduced and made available.
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post #11547 of 16634 Old 08-31-2016, 08:42 AM
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I'm trying to integrate and time align 3 subs connected to a MiniDSP 2x4 HD. 3 Rythmik F15HPs. Attached is the overlay graph for Impluse on the 3 subs.

Config is 2 subs up front next to mains about 14 ft from MLP, one near field 2 feet behind MLP. Impluse graphs of Sub Left and Sub Rear look roughly good (Sub Rear running 10.6 ms delay), but Sub Right looks really strange to me. I swapped Sub Right and Sub Rear and ran without 2x4 HD and same graphs. Looking for any thought on why these don't align.

Any tips or thoughts or suggestions would be appreciated.
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Audio: Yamaha CX-A5100 | Adcom GFA-555 + Outlaw Audio 5000 + Onkyo M-5010
Mains: Klipsch RP-160M + FM8 | Center: Klipsch RP-450c
Surrounds: Klipsch RP-160M | Klipsch R-15M | Polk Audio RC65i
Subs: Rythmik F15HP x4
Video: Vizio P702ui-B3 | Epson 5040ub | Oppo 203
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post #11548 of 16634 Old 08-31-2016, 09:02 AM
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Originally Posted by budeliao View Post
I'm trying to integrate and time align 3 subs connected to a MiniDSP 2x4 HD. 3 Rythmik F15HPs. Attached is the overlay graph for Impluse on the 3 subs.

Config is 2 subs up front next to mains about 14 ft from MLP, one near field 2 feet behind MLP. Impluse graphs of Sub Left and Sub Rear look roughly good (Sub Rear running 10.6 ms delay), but Sub Right looks really strange to me. I swapped Sub Right and Sub Rear and ran without 2x4 HD and same graphs. Looking for any thought on why these don't align.

Any tips or thoughts or suggestions would be appreciated.
Time-aligning 3 subs doesn't give you the best response per se – the response is swamped by room interaction. Use MSO for getting best results: http://andyc.diy-audio-engineering.o...tml/index.html
There's also a thread here at AVS: https://www.avsforum.com/forum/113-su...optimizer.html

P.S. You're posting in the wrong thread.

Markus

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Last edited by markus767; 08-31-2016 at 09:07 AM.
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post #11549 of 16634 Old 08-31-2016, 10:10 AM
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Quote:
Originally Posted by budeliao View Post
I'm trying to integrate and time align 3 subs connected to a MiniDSP 2x4 HD. 3 Rythmik F15HPs. Attached is the overlay graph for Impluse on the 3 subs.

Config is 2 subs up front next to mains about 14 ft from MLP, one near field 2 feet behind MLP. Impluse graphs of Sub Left and Sub Rear look roughly good (Sub Rear running 10.6 ms delay), but Sub Right looks really strange to me. I swapped Sub Right and Sub Rear and ran without 2x4 HD and same graphs. Looking for any thought on why these don't align.

Any tips or thoughts or suggestions would be appreciated.
Have you read the guide linked in my sig? It should provide direction.
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post #11550 of 16634 Old 08-31-2016, 10:19 AM
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Quote:
Originally Posted by markus767 View Post
Time-aligning 3 subs doesn't give you the best response per se – the response is swamped by room interaction. Use MSO for getting best results: http://andyc.diy-audio-engineering.o...tml/index.html
There's also a thread here at AVS: https://www.avsforum.com/forum/113-su...optimizer.html

P.S. You're posting in the wrong thread.
Ok, I have the MSO app downloaded and installed, but still in learning curve as when I try and do a run I get and error about no optimizable settings or something like that. Still working thru the user guide to figure out what I am missing. Using AustinJerry's guide for MiniDsp to this point. Will spend more time with MSO and post progress on MSO page. Thanks.

Audio: Yamaha CX-A5100 | Adcom GFA-555 + Outlaw Audio 5000 + Onkyo M-5010
Mains: Klipsch RP-160M + FM8 | Center: Klipsch RP-450c
Surrounds: Klipsch RP-160M | Klipsch R-15M | Polk Audio RC65i
Subs: Rythmik F15HP x4
Video: Vizio P702ui-B3 | Epson 5040ub | Oppo 203
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