does anyone use subwoofers in their setup?

[Antoine]

Thanks guys for waking up those previously dormant questions in my head again. They certainly are valid questions IMO. I remember I asked Thierry Massoubre about it a long time ago as well. I had to dive deep into my email archive but found the email discussion, it's from October 2012! From even before I bought my subwoofer.

My question:

If I may  I have a question. I’m planning to add an active subwoofer to my 2.0 set. Although my loudspeakers (Von Schweikert VR-5 Anniversary) are quite full range I’m doing this because of the peaks and nulls in the bass region present in my room. In the last few years I’ve placed an acoustic ceiling, optimized loudspeaker orientation/placement within the limits imposed by the room and even added a RPG Modex Plate basstrap. Although the sound reproduction has improved immensely in my room it hasn’t been enough for the bass region. Of course I was warned about this as you need BIG basstraps or a better room. Both options aren’t really options for me now. ;-)
 
I  have seen the options/settings in the online configurator for the subwoofer cut off frequency/crossover filter order but as I understand it may also be necessary to delay the output of the D-Premier because of the delay always created in/by a subwoofer. Many surround receivers/processors have this option but it seems to be missing in the D-Premier configurator. Now finally my question: is it possible to configure a delay setting for the sub output on the D-Premier? If not in a standard way or at the moment is/will it possible in a future firmware upgrade or through a custom configuration?

Thierry's answer:

All time-delays are basically already compensated inside the D-Premier. We can increase this delay up to 10ms upon request. You simply need to tell us what you want and we will program a configuration for you.

So yes, at least back then it was possible for Devialet to make a custom config for a customer in which they could add a delay up to 10ms. I have no idea if this is still possible/if the same conditions apply.

I remember I also sent an emails to JL Audio to try to get them to share the delays due to internal processing. Of course before asking Devialet to configure a delay I had to know the actual delays.

Q to JL Audio

I’ve bought a JL Audio Fathom F112 and to help me with the setup process (integration with two stereo loudspeakers) I’ve got two short questions I hope I can ask you.

2.     Do you know/have you measured the delay in milliseconds the F112 adds in between it’s input and output and does ARO influence this number?

Answer from JL Audio/Barry Ober from Sounddoctor.com. (Now you guys know where I found these links I shared on the previous page! )

2)  You are only the 2nd person to astutely ask that question!
I have a white paper about just that entire matching issue...
 
My white papers are here:
www.soundoctor.com/whitepapers
Look for the SUBS paper: www.soundoctor.com/whitepapers/subs.htm 
This is an in-depth discussion of every method of "adding a sub".
...and while you're there, enjoy the movie!
 
There's also my newest TEST CD , with the accompanying setup hints, here:
www.soundoctor.com/testcd 
The Test CD setup has guidelines about how to 'fix' the sub's group delay issue when using a Home Theater
receiver in a 2-channel critical music setup.
 
Here's a secret page (not linked on any menu, not indexed) which describes a professional mastering studio:
www.soundoctor.com/studio 
What this proves is just what a pair of correctly installed and set up 112's (not even 113's !!!) can do - it's astonishing.
 
Since room acoustics is certainly some 70% of the battle, Art Noxon has some great acoustic articles:
http://www.asc-home-theater.com/ht-articles.htm 
 
If you're interested in MORE acoustics links, see here:
http://www.bostonaudiosociety.org/links3.htm 
 
Please let me know if I can be of further help. This integration issue is not nearly as simple as it initially seems, and
you deserve the absolute best performance from  your sub(s) and their integration.

If you tell me the specific brands and models of what you have it would be good to know.
 
If you feel it necessary or useful for me to talk to you directly, tell me the phone and best times and I can call you
via the JL direct lines or even skype.
If you wish to call me directly, you can use xxxxxxxxx  11AM - 11PM Eastern time (GMT-5)

As you can see, there was no real answer to my question. I believe I gave up after this although I once thought about using Dirac and I even asked the Dirac developer if his software would be able to recognize/correct any delay in lower frequencies only.

Currently the only 'source' I am using is a PC so I am very much interested in Dirac Live for DRC and foremost for an optimal subwoofer integration (both time and frequency correction) but I am not sure if I can fit in Dirac Live in my current setup.

I own a Devialet 250 which is an integrated amplifier with integrated DAC and WiFi/wired ethernet streaming appliance. To this Devialet are connected two main front loudspeakers and a DSpeaker Anti-Mode 2.0 Dual Core. To the Anti-Mode is connected a single JL Audio Fathom F112 subwoofer.

The Devialet applies a 2nd order high-pass crossover @80Hz to the main loudspeakers and sends a full range analog output signal to the Anti-Mode. The Anti-mode in turn applies a 4th order low-pass crossover filter to the subwoofer and corrects the output for room anomalies. All processing on the subwoofer itself is turned off.

Can Dirac Live fit in this setup and if so how would be the best way? I could turn off the correction functionality/-filters in the Anti-Mode and only keep the crossover filters. Since both the subwoofer and Anti-Mode generate a certain (unknown) delay and are not "part" of the main loudspeakers would Dirac be able to recognize this/have large enough buffers to correct for any delay in the lower frequencies? In other words; will I still benefit/be able to use the impulse response and other functionality of Dirac?

I hope you can help me and I thank you in advance for your response.

Couldn't find an answer to that question.


So as you can see I indeed gave it a lot of thought and tried to find out what was possible but I didn't get far. I have to say though that I can't really hear/recognize any delay that may be there so at least the benefits outweigh any possible drawbacks. Of course this is in my situation, YMMV. My sub is close to and behind my left loudspeaker.

I also expressed some disappointment with Devialet pausing the plans for room correction as I had hoped to then be able to get rid of the Anti-Mode which of course also adds a bit of delay/latency due to processing. http://devialetchat.com/showthread.php?t...523#pid523