• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

My first attempt at Dirac this morning (on the 3800)

Found this note while Googling recently:
  • Dirac Live is incompatible with ceiling-firing Dolby Atmos-enabled speakers

Does this mean my ceiling speakers are a no-no for DL?

(note is under "Bugs and quirks")
 
Found this note while Googling recently:
  • Dirac Live is incompatible with ceiling-firing Dolby Atmos-enabled speakers

Does this mean my ceiling speakers are a no-no for DL?

(note is under "Bugs and quirks")
Atmos-enabled are speakers that bounce sound off the ceiling. They usually sit on top of base-level speakers. Regular ceiling or height speakers work fine with Dirac.
 
Maybe an optimal bass calibration method is in there with DLBC (which I personally also doubt) but they are also severely limited by the number of FIR taps available in the processors. A MiniDSP 2x4 has 1024 FIR taps per channel. The frequency resolution of a 1024 taps filter @ 48 kHz sample rate is 48000/1024 = 46.875 Hz. That means below 100 Hz for example you have just 2 frequency bins at 46.875Hz and 93.75 Hz. There's no way you can fix low bass problems with that. Audyssey XT32 uses a patented frequency warping technique to focus the limited number of taps to the problematic area to partially handle this problem. Storm Audio uses the highest number of taps in their machines and even they're very limited compared to 131,072 taps (2.73Hz minimum resolution) I regularly need with a PC for proper bass correction. In that respect, I wouldn't expect same Dirac ART performance from Sound United gear compared to Storm Audio, either. An AVR also needs to deal with the FIR filter delays and buffer uncompressed video continuously to compensate for the increasing number of taps so I don't expect anyone to come up with very high tap count receivers any time soon, too. I hope I am wrong.
Should we expect a low-end DIRAC ART?
 
I did not understand the question sorry my english is bad, i'm french
 
I did not understand the question sorry my english is bad, i'm french
De rien! If I understand your original question now, ART will not change. Low frequency is handled by Dirac Live Bass Control (a separate license). What OCA is saying is that ART may currently be hardware-limited and that the Denon or Marantz receivers may not perform as well as another product like Storm Audio.
 
Dirac Live applies some phase corrections and although I doubt the accuracy of these, Audyssey cannot do that at all. All its filters are in the frequency domain. Also Dirac Live can crossover subwoofer at any frequency (unlike the fixed frequencies of Audyssey) and has higher speaker distance (delay) level limits than Audyssey for the same receiver (I heard that from a trusted friend who tested both but did not yet confirm myself!)

If it time align all speakers including subwoofers, it would have done something improving on phase alignment naturally as (time and phase alignment are related) even without such filters that deals with the frequency domain. When comparing my REW graphs, I could see DLBC is effective but not a whole lot different overall, not as much as I anticipated.
 
x
Dirac Live applies some phase corrections and although I doubt the accuracy of these, Audyssey cannot do that at all. All its filters are in the frequency domain. Also Dirac Live can crossover subwoofer at any frequency (unlike the fixed frequencies of Audyssey) and has higher speaker distance (delay) level limits than Audyssey for the same receiver (I heard that from a trusted friend who tested both but did not yet confirm myself!)
Coming from you I am a little surprised and had little doubt you know your stuff. However, what you stated about Audyssey filters seem like something people have been repeating on forums many times and I never know if they were false, true, or to a point..

Since I was able to get smoother 15 to 200 Hz combined results of two towers and subwoofers than DL could even with BC, Audyssey must be doing something right in that range, and in some ways. So I ask Audyssey about what you said in this post, and their response was that there were a lot of misinformation out there. According to them, Audyssey filters do not alter the phase, thus no optimization is needed, and that Audyssey time-aligned all speakers, and the filters are in the time domain.

Unless we don't believe what Audyssey is telling us, we should do our part not to perpetuate misinformation, not that I am a fan and I don't use it anymore, but just want to be fair. Regarding the fixed crossover frequencies of Audyssey, I don't like that either but I seem to remember that their response to that was, they don't set crossovers, Denon/Marantz do (same for the large vs small thing), but that's by memory, need to do a search to confirm that. Just did, first Google search result is from 2011:

Audyssey LabsMarch 25, 2011 08:43
MultEQ does not set crossovers. It simply finds the roll off that each speaker has in the room and where it's placed. The crossovers are set by the AVR maker. There is a benefit in raising the crossover up: the MultEQ filters in the subwoofer channel have 8x more resolution and so will produce a smoother bass response. I would recommend using 80 Hz.

So, I agree with you on this, though again, want to fair that Audyssey does not have full control of how everything is done. I can see that DL may begin to lose some control too not that they are much more widely adopted by AVR/AVP manufacturers, big dogs like Masimo are going to exert influence, for various reasons. What Phil Jones just alluded to about adding bass management to the regular license is a sign, albeit a much welcome one.

By the way, while searching for crossover frequency, I came across the following response to a question about time domain filters as well, also from 2011:


Audyssey LabsAugust 10, 2011 14:48
Hi Jonas,
You are right that there is no way to control the sound after it leaves the speaker. However, we can measure the effects of the reflections that arrive after the direct sound by looking at the time domain response. It has a certain pattern to it that will depend on the time of arrival of those reflections. Based on that pattern and the similarity of patterns across multiple measured locations we can identify the problems caused by reflections. Then, a filter is created to invert those problems as best as possible.
The key is to not think of the filtering in the time domain. It's not like a graphic equalizer that can only raise or lower the amplitude at certain frequencies. Our filters are in the form of impulse responses that operate on the audio signal through an operation called convolution. As such, they are affecting the signal in each channel in the time domain--hence the name. An additional benefit of such filters (also called FIR) is that they operate in the time-frequency domain as well. That means they can be used effectively to lower the ring down time of room modes in the low frequency range.

I can see why users such as me and @Steve Dallas could get comparable results to Dirac Live, yes, even vs DLBC though I would definitely give DLBC the edge overall, cost more though obviously.
 
This is the conclusion I am reaching. I can't even say I find Dirac to be better than XT32 if you know what you are doing. I am tempted to create a comparison thread with tons of graphs, but that will be a LOT of work.

Here are the bass frequencies of my 4800 with Revel F206s and SVS SB2000s (2) with and without DLBC. Other than time alignment, what exactly did I pay $350 for?

Purple and brown are Dirac Live. Green and blue are Dirac Live with DLBC.

View attachment 338381
Having had an RZ50 w/Dirac + UMIK and very similar speaker setup to you, I concur 100%. I sold my RZ50 because it was overheating in my media cabinet and needed something with a shorter profile so that I can sit an AC Infinity cooler on top, so I got an x3700h. I was expecting to be disappointed in XT32, but after setting it up with the MultEQ iPhone app, removing the midrange compensation dip, etc I think I might actually subjectively prefer the XT32 outcome..

I know that I could probably Google this answer, but do you know what the point of "Ratbuddyssey" is? What additional functionality does that process offer over just using the MultEQ app? I currently like the outcome, XT32 is producing, but I CAN'T STAND Dynamic EQ, it makes the surround channels too loud and distracting at low volume.

Any additional tweaks I should pursue?
 
Having had an RZ50 w/Dirac + UMIK and very similar speaker setup to you, I concur 100%. I sold my RZ50 because it was overheating in my media cabinet and needed something with a shorter profile so that I can sit an AC Infinity cooler on top, so I got an x3700h. I was expecting to be disappointed in XT32, but after setting it up with the MultEQ iPhone app, removing the midrange compensation dip, etc I think I might actually subjectively prefer the XT32 outcome..

I know that I could probably Google this answer, but do you know what the point of "Ratbuddyssey" is? What additional functionality does that process offer over just using the MultEQ app? I currently like the outcome, XT32 is producing, but I CAN'T STAND Dynamic EQ, it makes the surround channels too loud and distracting at low volume.

Any additional tweaks I should pursue?
Ratbuddysey allows you to precisely enter and edit control points on each target curve instead of trying to manipulate them with your finger in the app. It also does a better job of graphing the measurements and gives you access to the same deep settings as the MultiEQ app. Unfortunately, it does not seem to be supported and is not compatible with at least some of the newer AVRs. You can do the same things in a code editor if you understand JSON.

Screenshot (2).png
 
Last edited:
Ratbuddysey allows you to precisely enter and edit control points on each target curve instead of trying to manipulate them with your finger in the app. It also does a better job of graphing the measurements and gives you access to the same deep settings as the MultiEQ app. Unfortunately, it does not seem to be supported and is not compatible with at least some of the newer AVRs. You can do the same things in a code editor if you understand JSON.
Gotcha. I’d love to have that functionality and a calibrated mic, but $200 + mic seems ridiculous for the MultEQ-X software.
 
Gotcha. I’d love to have that functionality and a calibrated mic, but $200 + mic seems ridiculous for the MultEQ-X software.

One poster on Audioholics.com posted his new UI that looks like a graphical version of Ratbuddyssey (though not related). It looks like it is preliminary, but it has potential, a welcomed alternative to the $200 MultEQ X.



And, if I remember right, Simple Home Cinema has a version too, that is based on Excel so the interface would be similar to Rat's but much easier to use, I would think:


For $11, if I were still using Denon or Marantz AV devices, would have given it a try, though I like the free Ratbuddyssey just fine.
 
One poster on Audioholics.com posted his new UI that looks like a graphical version of Ratbuddyssey (though not related). It looks like it is preliminary, but it has potential, a welcomed alternative to the $200 MultEQ X.



And, if I remember right, Simple Home Cinema has a version too, that is based on Excel so the interface would be similar to Rat's but much easier to use, I would think:


For $11, if I were still using Denon or Marantz AV devices, would have given it a try, though I like the free Ratbuddyssey just fine.
I’m gonna start by just installing the Audyssey app on my iPad and using a stylus and see where that gets me.
 
I’m gonna start by just installing the Audyssey app on my iPad and using a stylus and see where that gets me.
If you are good with a steady hand, you may go far enough, but for pretty curves, no it would be near impossible.:) So, good luck, hope you will at least get the bass to sound smooth.
 
If you are good with a steady hand, you may go far enough, but for pretty curves, no it would be near impossible.:) So, good luck, hope you will at least get the bass to sound smooth.
I’m fine with the rest of the target FR once you remove the midrange dip, wouldn’t it be grand if Audyssey just provided you with an option to do +6 bass curve like Dirac?!
 
Unless we don't believe what Audyssey is telling us, we should do our part not to perpetuate misinformation, not that I am a fan and I don't use it anymore, but just want to be fair.
The information is accurate. Dirac applies phase correction and Audyssey does not. Frequency and phase response are both in the frequency domain. It's the impulse which is in time domain. You need to learn the basics before making such assumptions.
 
I love Audyssey's DynEQ, DIRAC offers the same thing?
As mentioned already it doesn't. They leave it up to the brand that has implemented Dirac on their hardware to do that. Some devices, such as the Monoprice HTP1 do but I'm not aware of any others that do.
 
The information is accurate. Dirac applies phase correction and Audyssey does not. Frequency and phase response are both in the frequency domain. It's the impulse which is in time domain. You need to learn the basics before making such assumptions.
I didn't have to learn it, I asked Audyssey about it and they gave me the answer. If you are going to insist on your claim, you need to prove it somehow, otherwise you can just say anything you want. Or may be you know more about how they did their filters than them? In that case I would have to wonder why, no sarcasm, am series. I never said anything about impulse response, and you assume I have to learn from you to know that is in the time domain? How good are you with Fournier, Lapace, Z transforms etc.? I do know you are a good programmer, and I appreciate your work. I also never said Audyssey does phase optimization that Dirac does.

I always thought someone seemingly very knowlegeable like you are, would be more open minded and am really sory to see you reacted this way. Telling others to "learn the basics before....", how assumptious! And again, it's not relevant anywhere as I did not make things up myself, I made it clear I was told by Audyssey. May be you can ask them too.

If your rude response is in reaction to the tone of my post, then be clear, I did not anticipate it would offend you. If so, let me apologize right now, and we can move on.
 
Last edited:
Back
Top Bottom