Time-alignment of Speakers

[sircharles]

Originally Posted by chessman

Has anyone used a time-alignment device (like a Rane AD22s) to delay the main speakers signal output enough to integrate a pair of "stereo" subs? If so, I would love to hear about your experience. Does it play well with an active cross-over? Does it degrade the sound?

I will be trying to tackle time alignment, speaker correction and integration of two subwoofers using a DEQX PreMATE+. Read or look-up at the DEQX HDP-4 and HDP-5 if you have active speakers. My DEQX should arrive early next week.

[crwilli]

Originally Posted by chessman

I used his technique to time align my third sub that is used exclusively for LFE in home theater operations. I set my other speakers to 9 feet and that sub to 21 feet to achieve what is, in effect, a 12 millisecond delay of the mains. The problem in the two channel mode is that I do not have a device like a MEN 220 or a Rane to delay the mains.

Randy,

If the inherent delay of the sub is equal to the time it takes to go 12' AND your sub is exactly in the same position as your Mains, this works.

What would do if your sub is 5' 6" from the LP and the Mains are 11' from my LP? Eg the mains are already slightly delayed from the sub.

Craig

[chessman]

Originally Posted by crwilli

Randy, If the inherent delay of the sub is equal to the time it takes to go 12' AND your sub is exactly in the same position as your Mains, this works. What would do if your sub is 5' 6" from the LP and the Mains are 11' from my LP? Eg the mains are already slightly delayed from the sub. Craig

The Rane is adjustable from 2 to 999 milliseconds in .1 millisecond increments on a per channel or stereo basis. Thus, I think each sub could be individually set regardless of differing distances of actual sub location.

[crwilli]

Originally Posted by chessman

The Rane is adjustable from 2 to 999 milliseconds in .1 millisecond increments on a per channel or stereo basis. Thus, I think each sub could be individually set regardless of differing distances of actual sub location.

but is the delay set no matter where the individual speakers are either relative to the LP or to each other?

Sent from my iPad using A.Aficionado

[chessman]

Originally Posted by crwilli

but is the delay set no matter where the individual speakers are either relative to the LP or to each other?

Sent from my iPad using A.Aficionado

Keeping in mind that I do not have the actual unit yet, I believe that the delay is being applied to the mains (NOT the subs). I would think the delay being applied to each main speaker has to be the same or the stereo image would crash. Thus, I also think that one sub could be integrated, but that two subs (unless equidistant) would not.

[Anerol]

Dear sirs,

im very interested in this subject since I am experimenting in the same filed. Here is what I do.

My electronics are from Accuphase including the DG-58 voicing equaliser and the DF-55 digital x-over. The latter allows time alignment of each speaker benefitting from his own channel.

My speakers are a set of Sonus Faber Minima driven by two A-46 and a Sonus Faber active sub. While all this allows to adjust fairly easily the delay the problem is how much.

My dealer is also at home in pro audio and PA systems hence knows his way around. He has come to my house with his quite expensive measurement equipment and we have set the DF-55 to compensate for delay differences. The result? Absolutely stunning. An integration of the sub to the music never heard better. Maybe it's normal that I am blown away but others have stepped by for a listen and are confirming what I am hearing. If ever you have a capable Accuphase dealer around you who has gained experience in this don't hesitate to go and listen. Sound staging, depth of the image, flow, integration - fantastic.

Here comes my point. Each time I change something I would have to have my dealer come around and measure again to redo a proper setting. While this fun each time we do this it is also an expensive exercise.

As an alternative to this I downloaded the digital six audio app and in app downloads to measure the (group) delay of each speaker. While this shows some results it is clearly not as good as the pro measurement and setting. Does anyone of you have experience with group delay measurement equipment or software that works and is affordable?


Anerol

[srosenberg]

I cross my Wilson mains to my Seaton Submersive sub using an electronic crossover (XTA) and the absolute best integration I've ever achieved was once I introduced a delay on the signal to my mains.

Distance measurements of the speakers to the listening position, according to Barry's theory, indicated that the optimal delay on the mains would be around 9 msec. So, I started at 0 msec and ran a sweep in my room using REW to plot the results. I tested at 1 msec increments up to 12 msec, then narrowed in testing the best range in 0.1 msec increments. The optimal results were in fact at 9 msec, so in my case at least, the theory proved correct.

I've been high passing my mains for a long time, as I easily hear the benefits of doing so, even with speakers that play down to 30 cycles. With some work, I could usually get the integration to be pretty good. Once I started time delaying the mains, everything just snapped right into focus. There is absolutely no localization of the sub whatsoever - just one beautifully cohesive sound field.

If you have the equipment, try it - you'll likely be surprised at what you hear.

[chessman]

srosenberg, what are you using to delay the signal on your mains?

[vinod_david]

Anerol, welcome to AA.

[o0OBillO0o]

Originally Posted by crwilli

The MEN220, which I am using now as only an active crossover, allows you to set the distance from the listener to adjust timing. You can adjust to your hearts content to set the relative timing of each speaker to the others. I don't have the elixir yet but I am getting closer getting my Fathom F113 v2 to merge well with my Strads.

+1

It's so simple and straightforward with the MEN220.