Windows-based Passive Speaker Group Delay Correction: Is It Here Yet?

[nxrm]

 

Though still much the newbie beyond grasping the reasons for room eq, and with little hands on knowledge, I did find the DEQX website quite informative. http://www.deqx.com/product-hdpExII-overview.php   But as I rarely attend shows, I doubt that I will ever get to hear a DEQX enhanced system. Of course, that's hardly surprising as while currently DAC shopping I'm finding next to no DACs offering speaker time alignment. Sure, this feature would and obviously does add much to the final cost of any great sounding DAC. And this is a real loss for audiophiles owning almost any kind of speakers, considering that DEQX's Kim Ryrie, whose been at this since the 90s, has not been the only hardware engineer who has successfully fought and won the speaker time alignment war.

http://www.trinnov.com/technologies/loudspeaker-room-optimization/?lang=en_us

 

But what of audio software engineers? Stereophile and others supporting this market are well aware that computer audiophiles are very established and that our numbers are growing very fast. Once someone in our realm creates the algorithms for software DEQX and Trinnov did for hardware-then couldn't the same microphone, an excellent and affordable A/D converter and a laptop with a Skylake or Kabylake processor make equally short work to get even passively crossed speakers to deliver excellent phase response? AND do so with the DAC of our choice?

 

Don't get me wrong. DEQX and Trinnov Audio hardware solutions are stunning achievements, offering an elegant "one box solution" for room eq, subwoofer integration, and, most enviably, speaker time alignment-AND of even passively crossed speakers.

But doubtless many of us much prefer the sound and design of our DACs. Nor did we likely soon after forget about the fat bundle spent on it. So why would we want to end up paying for another "built-in" DAC, and which might not sound quite as good to our ears?

 

Instead, with the sophistication and computing power of today's software functionalities and CPUs, can it really be that hard to do two speaker group delay speaker correction from your desktop? And at least for those whose music sources are all digital-and with so many of today’s best systems being computer managed in one or more important ways-this certainly is how many of us want and expect group delay correction of passively crossed speakers to evolve.

 

 

 

 

[Kal Rubinson]

I hate to say this but "Of course!"  Many of us, even in Stereophile, have been proponents of software DSP just as we have been for software music management and we feel, as you do, that dedicated and specialized hardware solutions are more expensive and have limited shelf-life.

[Yucca06]

For 2 speakers only, it's very easy.

You've got a dsp engine integrated within roon with delay settings (you can also add a convolution file, or use a very good Eq).

You can alternatively use VST or AU plugins with your audio player to do this (Audirvana+ for Mac, Jriver for Windows, ie.)

[Keith_W]

PASSIVE speaker time correction is not possible. You must have control of each individual driver unit. In other words, each driver unit has its own power amplifier and DAC channel. I have built a system like this. It doesn't have to be expensive, but it can be if you have a predilection for luxury audio and name brands. 

[krzys]

13 hours ago, Keith_W said:

PASSIVE speaker time correction is not possible. You must have control of each individual driver unit. In other words, each driver unit has its own power amplifier and DAC channel. I have built a system like this. It doesn't have to be expensive, but it can be if you have a predilection for luxury audio and name brands. 

Yes it is possible with Acourate..... I think it analyzes some frequency bands and calculates the delays but of course it will never be as efficient as having separate channels.

Chris

[Keith_W]

I have been using Acourate for quite a while in my system evolution. I first started using it when I still had my passive crossover in place. I am 90% certain that it is not able to correct time delay unless you have an active crossover. 90% certain, because I have not seen the setting in Acourate, have not seen it described in Mitchco's book, nor have I seen anybody say that it is possible. For the remaining 10% you'll have to ask Uli. 

[krzys]

Hi Keith, I'm using Acourate and my system is fully active, 5 ways but I'm absolutely sure that Uli recommends Acourate for passive crossovers too. My pal did it with good results. You have to run the room correction macros as usual. I suggest you ask Uli ;)) or search the Yahoo Acourate group forum. 

[Keith_W]

krzys Acourate does work for passive crossovers. The question is whether it can perform time alignment with a passive crossover in place. My understanding is that it can not. 

[krzys]

Hi Keith, 

my understanding is that it can al least partially. I found this from Uli himself in a replay from  July, 8th 2011 in Acourate forum on Yahoo Groups:

"no, the time alignment is not applicable to passive systems. The only chance for some alignment is to shift the speaker drivers if possible. But Acourate will also correct the time behaviour of passive speakers too."

So the alignment procedure can not be used , that's normal but some correction is applied. My Friend got the same answer. 

Chris

[mitchco]

Late to this post... Yes, time alignment is not applicable to passive systems. However, Acourate will correct the time behavior of passive speakers with an overall time correction using Macro4 and excess phase correction. But there is a limit to thatl, depending on how much the drivers are offset. I show an example in my eBook trying to correct a passive system where the midrange driver is outside the range of Acourate's excess phase correction - i.e. the physical offset is too great. However, @dallasjustice was able to apply a good overall time correction to his JBL 4367 paasive speakers as the woofer and tweeter are close enough in physical alignment for the excess phase correction to do it's magic Would be a curious experiment to actually time align one speaker and leave the passive network in the other and see if there is an audible difference... The moral of the story is try the overall time correction first and if it is outside of Acourate's parameters to align the step response, then time alignment, using digital xo is the answer.