Behringer Ultracurve DEQ2496 - ways to use it?

[paulspencer]

I have plans to get hold of the Behringer Ultracurve DEQ2496 and I'm looking for ideas/advice/discussion on ways it might be used.

My system:
* 2 way MTM TL speakers with Vifa P17 & D25AG - soon to have an active analogue crossover added (DIY)
* 2 x ~30L AE speakers AV12 subs - sealed

I intend to place the subs either side of the couch and cross at 60 - 80 Hz. This seems to get a fairly smooth response to start with. Then I can eq the whole system (before the signal goes to the active crossover).

Having looked further into the user manual, I find a very powerful set of options, on which I'd like some comments. These include:

* Dynamic EQ to protect drivers from overexcursion - I could set it up so that it's not possible to drive anything beyond xmax

* Dynamic EQ to reduce the impact of power compression - most subs tend to change the frequency response as you turn it up due to power compression - at a preset point I could cut back the midbass so the response stays the same

* Dynamic EQ to compensate for the changing sensitivity of the ear to LF at lower volumes

* Digital delay either to the tweeter, or the subs

* Widen stereo image (not sure if this would be gimmicky)

* Dynamics processors - compressor - reduces extreme dynamic range when it's too much for the system at high output; expander - reduces signals below a threshold (noise)

* EQ to get the bass response I want - previously I was boosting the overall sub level, but with an active xo this would raise the crossover point - by using eq the xo point is not messed up

* EQ to improve poor recording mix - I find a lot of recordings are objectionable - treble is overdone, bass is thin and lacking depth, midrange is glaring

* EQ to deal with room modes - I can reduce them by placement quite a lot, but don't have the option of room treatment at the moment

* EQ to suit preferences - BBC dip etc - in place of my tweeter pad which I have at the moment

Suggestions, comments, criticisms, and in particular shared experinces welcome

[paulspencer]

For those not familiar with what I'm talking about (and some who are) ...

Behringer Ultracurve DEQ2496

A review of Ultracurve's little brother by Thorsten Loesch

Here's what it looks like:

[dswiston]

So far I've used only the auto-eq feature of my Ultra Curve extensively, it works rather nicely to help correct room problems (mostly for your listening spot, it won't EQ so the entire room is flat), especially when you are renting and have limited room treatment options. I have yet to use but am planning on using the dynamic limiter so as to protect my open baffle projects. I've left compressing/expanding alone for now. I've poked around with manually EQ'ing by ear but auto-eq works just fine. You can also set targets for the auto-eq meaning you don't have to target a flat response. If you want a tame high frequency, you can. Want to get bass crazy? You can. Want that $10,000 overpriced audiophile speaker at the local shop, boost up the treble (hehe cheap shot).

I'm pleased with the unit. It also serves as my DAC seeing as how I'm poor and can only afford a cheap DVD player and buying soley a high quality DAC is not economical. For equalizing a favorite listening spot, auto-eq works wonders. To an extent, baffle step problems because of room response and OB low frequency roll off can also be fixed.

Did I mention I also like to have the RTA on showing me a neat light show of the frequency domain of the music playing.

The only downfall is that I seem to incur digital clipping often if the EQ'ing requires a large boost in an area. Its most likely caused by the music I listen to being compressed and on the verge of digital clipping already, so its not all peaches and cream.

[paulspencer]

I spoke to a PA guy recently who thinks there is no worthwhile bass below 50 Hz. Yet when I heard his bandpass sub tuned at that point, I could tell he could gain a sense of depth and weight in the bass by going 10 Hz lower. I'd like to be able to demonstrate that I'm not insane in shooting for 20 - 25 Hz in room extension. IOW, I'm thinking RTA would be very handy, novelty factor aside.

Could you elaborate a little more on using it as a DAC? I'm not really clear on this, what exactly it means, what are the advantages, and how to do it.

I assume this means getting digital out from your source (hence bypassing the dvd/cd player DAC), then sending the analogue signal to the preamp. If so, how good is the DAC?

Question for the aussies:

Looks like I will start to need quite a lot of connections now that use XLR connections. Any suggestions on how to do this cheaply? My first thought is to get XLR - RCA adaptors but I wonder if there is a cheaper way. Suggestions for good cheap suppliers?

[sfdoddsy]

Are you able to do any measurements on your room so you can tell exactly what is needed?

If so, I would use the parametric EQs to fix bass peaks, and then use the auto-EQ for more minor EQ of the whole system. You probably shouldn't use any of the compression or limiting options, they've designed for pro audio use. The dynamic EQ can be handy if you play your music really loud.

However, since you plan on doing an active crossover for your mains anyway, I can't help wondering if you wouldn't be better off with Behringer DCX 2496.

Then you can have one box that will give you your crossovers, allow you to EQ each driver (especially important for the subs), do delays and dynamic EQ if you want it. And the price is about the same.

For your situation the DCX would be a much finer tool, especially if you are going to have the subs so far away from your mains.

Cheers

Steve

[ThorstenL]

Konnichiwa,

Originally posted by paulspencer
I have plans to get hold of the Behringer Ultracurve DEQ2496 and I'm looking for ideas/advice/discussion on ways it might be used.

I have written a moderatly complete set of notes, please look here (Yahoo subscription to my discussion group is forced by Yahoo, not by me):

Suggested target curves and setup techniques for Pro Audio Digital Equalisers in home systems for Room correction and general system EQ

I'd leave the dynamic EQ alone, too unpredictable as you will have a hard time know what to compensate, even with good basic measurement setups.

Originally posted by paulspencer
* Digital delay either to the tweeter, or the subs

The second output is of much lower quality than the main one, use only for uncrittical stuff, so IMHO not the tweeter.

Originally posted by paulspencer
* Widen stereo image (not sure if this would be gimmicky)

Works well if used the right way (eg. ONLY widen the LF stereo-base, not at high frequencies).

Originally posted by paulspencer
* Dynamics processors - compressor - reduces extreme dynamic range when it's too much for the system at high output; expander - reduces signals below a threshold (noise)

I found the dynamics to suffer from the problems as all single way compressor/expanders, not quite good enough. You can sometimes use the DEQ Expander to get dynamic range from compressed recodrings, but the time constant settings are tricky for an ex studio pro (eg me) to get right.

Originally posted by paulspencer
* EQ to get the bass response I want - previously I was boosting the overall sub level, but with an active xo this would raise the crossover point - by using eq the xo point is not messed up

That you can do.

Originally posted by paulspencer
* EQ to improve poor recording mix - I find a lot of recordings are objectionable - treble is overdone, bass is thin and lacking depth, midrange is glaring

* EQ to suit preferences - BBC dip etc - in place of my tweeter pad which I have at the moment

That too, and well.

Originally posted by paulspencer
* EQ to deal with room modes - I can reduce them by placement quite a lot, but don't have the option of room treatment at the moment

Yes, this too can be made to work well.

I would see the DEQ primarily as room EQ and as "re-equaliser" for recording (eg re-mastering).

Sayonara

[paulspencer]

Steve,

I have an opportunity to get the DEQ cheap, considerably more so than the DCX and it appears it will do things I want that DCX will not do. I'd like to add DCX later.

DCX is a crossover more than an eq unit. The DEQ is an eq unit, which is what I want as I can do an active xo very cheaply (although with less functionality and power). Ideally, I'd like to use both in the future. I will need to get a mic or borrow one to do this right.

It has previously been suggested to get the DCX, but for reasons I'd rather not go into, this isn't an option right now.

[paulspencer]

Paul Spencer:

Could you elaborate a little more on using it as a DAC? I'm not really clear on this, what exactly it means, what are the advantages, and how to do it.

bump!

I'm still looking for an answer to this!

Does DEQ actually have a better DAC than typical DVD players?

[ThorstenL]

Konnichiwa,

Originally posted by paulspencer
Does DEQ actually have a better DAC than typical DVD players?

Absolutely, when compared to typhical low budget DVD Players, no if you are asking about High End DVD/Multiformat/AV Players.

Sayonara

[paulspencer]

What else do I need with DEQ? ... I am contemplating a DIY mic, or the Behringer ECM8000 mic or an SPL meter. With the latter, I can also use it to get levels, which I would like to have.

The problem is, it's response is not flat. However, with the autoeq, I understand that I can set the target curve as the inverse of its response. This would then yield a flat response. I'm not sure if I can get around the response of the meter where it may be required to be flat for other uses, either with DEQ or measurement in general.

Is it possible to calibrate the response of an SPL meter in speaker workshop if I have the correction factors (say with the Radioshack analogue meter?)