BEHRINGER Ultracurve Pro DEQ2496

Behringer devices are very well known in the professional audio community – I mean sound engineers, mastering suites, recording studios and musicians, both pros and amateurs. The German company can provide you with a bulky catalogue of audio gear and gadgets that an audiophile will not ever need, however, there are also some devices that may come in handy even in high end audio.

Small but mighty

The Behringer Ultracurve Pro DEQ2496 is a mastering processor – its role is in fine tuning recordings before they are sent to a “printing” house. On top of that it is a very useful tool for concert PA systems as it helps suppress feedbacks, optimize stereo field or handle the proper amount of reverb. The Behringer is an extremely versatile device with dozens of different settings and I can guarantee that many of them will keep you, the audiophile, busy for weeks.

I spent several weeks with the DEQ2496 during which period I wrote a book of notes from listening sessions. The following text is an extract of the most essential findings. If you need to know all the functionalities that the processor offers I’d rather recommend visiting their website and download the manual – it is very well written and will guide you through all the settings and functions.

Your new LEGO

The Ultracurve Pro is a modular system, alike the Lego blocks. The software modules can be activated and deactivated independently of each other, daisy chained or pooled. That is basically how the device works. With the help of push buttons a user goes through a system of menus (similarly to your mobile phone operating system) and sets the parameters. Should you do something wrong it is possible to either correct it or reset the default. All information is shown on a monochromatic orange display which is dimmable in several steps.

For most hifi users the equalizing module is one of the most attractive. Though some abbreviations may sound unfamiliar once you test them you will understand what they are about immediately.
The paragraphic EQ is a standard “graphic equalizer” that can control 31 audio bands from 20Hz-20kHz. There is 31 virtual sliders on the screen that can boost or attenuate the band in the range of +/-15dB. The processor allows you to choose to which extent the adjacent bands should be affected too (creating the characteristic bell shape of the frequency response) or you can apply a SHELVING filter. It is possible to choose if those (or any other) adjustments should affect both channels simultaneously in a stereo mode or just one channel at a moment.

The parametric equalizer (PEQ) is even more powerful. There are 10 open positions, each of them can be assigned any center frequency you like and decide, how wide the audioband should be (from 1/10 octave to 10 octaves) and what the gain (positive or negative) should be. The shelving filter is available too as well as high and low pass filters with the roll off up to 12dB/octave.
The PEQ is extremely effective in taming acoustic modes in listening rooms – with a bit of patience it is possible to achieve a ruler flat response from your speakers. The Behringer provides the user with a build in generator of pink noise so a measuring microphone is the only tool that is required.

The dynamic equalizer (DEQ) is sophisticated software that allows to set THRESHOLD, RATIO and GAIN plus ATTACK and RELEASE – there are 3 such equalizers available for each channel. At home such a function can be useful to prevent too high dynamic peaks (when you listen at high volume) or to boost the dynamics at low volumes, typical for night listening sessions.

There is another great tool that affects the dynamics: in the DYN mode the Behringer works as a dynamic compressor or expander. The options include limiting (cutting off the dynamic peaks), soft limiting (the same but with gentle rounding of the cut-off peaks) or expanding (again with the THRESHOLD, RATIO, GAIN, ATTACK and RELEASE, all independently adjustable). I do not assume that the limiter is something to bother about in hifi as audiophiles have the opposite problem – the recordings come limited and squashed so it may be worthwhile trying expand them.

Let’s suppose that your listening environment is assymetrical or has assymetrical acoustic parameters (like when one wall is reflective and the other wall absorbing, which is often the case in modern interiors full of glass and gypsum boards). Or let’s pretend that, for some reasons, you are forced placing the main speakers assymetrically to your listening position. That’s why the Behringer features the WIDTH module. It enables to virtually simulate any width of stereo base to the point when both channels become separate music sources and the stereo ceases to exist or, vice versa, when both channels become one in mono sound. The WIDTH module also allows rotating the stereo image – thus you can optimize the stereo field for a listener that sits off axis. The WIDTH module also allows you to compensate the imaging for individual audio bands (lows are less directional than highs, for instance, so you may require only certain frequencies to be affected).

There are many other modules, filters and settings – when you are done with all of them it is possible to store the configuration in one out of 64 memory slots.The slot can be renamed according your preference. Thus one can optimize its listening field or equalizing preferences for individual music genres, day or night, one or more listeners, one or another speaker set, open or closed windows, your favourite album, you name it. The BYPASS function is an easy way to compare the before and after sound on-the-fly.

So, even now when you are done and ready to listen there is so much to do with the Behringer. The RTA spectral analyser analyses the audio signal in real time – the user can select the resolution of the RTA as well as the peak hold time and how fast it should react. One can also choose which input or output should be monitored. As you know from (now vintage, time flies) tape decks the moving graphic bars can be almost hypnotic but here they are also very informative as they show the numeric values of peaks and corresponding frequencies. Good for learning, especially at low frequencies – you may be surprised how high the center frequency of your favourite “deep” bass is, for instance.
Do you want another gadget? The METER module has two modes – digital (LED bars) and analogue (VU meters simulation) with the indication of clippings like we know from tape saturation control.

The real world evidence

I was like a kid with a new toy. I was busy with the DEQ2496 for 24/7. Each recording can be improved in one way or another. Fortunately, after few days the initial excitement settled down and I took a bit more systematic approach to exploit all the Behringer offered. Long story made short there are four modules that will be indispensable for an audiophile life:

• Equalizing the in-room speaker response, alias the parametric equalizer.
• Analyzing the audio signal, alias the real time spectral analyser.
• Manupulating the soundstage depth and width, alias the stereo imager.
• Healing the loudness war victims, alias dynamic expander.

How appealing is the ruler-flat sound?

With the help of other measuring software I knew exactly where the peaks and throughs in my listening seat are. So I knew exactly how where to add and where to subtract. It was not that simple though...
In each position in a listening room what we hear is the result of pretty complex interaction of multiple waveforms that collide, multiply or cancel in impredictable fashion. Well, it is predictable to some extent so the rough adjustment is pretty straightforward (and the Behringer has an auto-routine for this), but real fine tuning is a chore. The act of programming the right correction at six center frequencies to arrive to the smoothest response possible took me whole day. Late at night I ended up with the response that was within +/-2dB between 30Hz and 20kHz and went to bed.

The next morning, energized by a cup of coffee, I set to critical listening. The hypnotically moving segments of real time analysers informed me that for the most time I was listening to a clipped signal: Goldfrapp (Black Cherry, Mute, CD STUMM 196). The red alert diode was flickering all the time – perhaps it would be useful to install a thousand-watt spotlights in all mastering suites to prevent this from happening? Anyway, Goldfrapp is a nice piece of music so let’s listen to how it sounds when optimized for the ruler-flat response.

The difference wass short of dramatic but was clearly audible. The bottom end was more articulate and punchier, more focus less smear. The whole sonic picture became denser, I could hear more of the instruments. Some sounds that were buried deep in the mix before (like a tambourine, for instance) had become better discernible.

And I Don´t Want to Fall in Love

Chrise Isaak’s Wicked Game (Reprise, 7599-26513-2) also improved in the equalized system. The bass guitar was fuller and heftier with beautiful round and analogue timbre. The soundstage was very legible, each instrument had precise focus and was distinctive within the soundstage. The strings appeared with breathtaking resolution, the voice became fleshy and full. Let’s see what the BYPASS does...

The sonic character through the bypassed processor did not change, yet there was a profound difference. The guitars became wiry and mechanical sounding. The natural music flow disappeared and the amount of detail dropped. The choir that sings ´...this world is only gonna break your heart...´ was more muffled and the voices became mashed together. The snare drum that I liked in the equalized system lost its ‘snariness’. The most important music instruments, the Isaak’s voice, became sleepy, veiled and inarticulate. When I switched back to the EQ mode the music got back to life and acquired more tangibility.

At the crater's edge

The piece Craters Edge (Malgorzata Zalewska, Master and Margarita, MEG 18057) is basically quite minimalistic composition of harp glissandos and low-level synthesized sounds. The lows reach to 18Hz and the harp soars up to 17,000Hz (0dB), 20,000Hz respectively (-10dB). Listening to such a recording on a lesser system means listening to the harp with continuous rumbling in the background, more hum than music. The sustained tones soon excite room modes so turning the volume up results into unlistenable stuff. And that was more or less what I was receiving in the bypassed system.
Once the parametric equalizer was called to action the sound changed. The low-frequency noise actually became a synthesized melody. On top of that I found out that there were more than just one synthetic bass line in the background – the interweaving structure was now clearly discernible.

The imaging magic

The WIDTH module uses a sophisticated Stereo Imager that can manipulate the size and the symmetry of the stereo image. Do we really need it? If you, for example, play back a mono recording and the sound you hear does not come from the dead center, and if you are not able to make it coming from the center even after moving your speakers, then you will make a use of the Stereo Imager.
It allows to adjust the relative strength of each channel within +/-90°without moving the center image and to adjust the width of the image. I used a single-miked Underground piece from The New York Girls´Club (Rebecca Pidgeon, Chesky JD141) to see what I could do. The good news is that I could move the speakers closer to each other and further apart electronically, that is without moving them at all, without any loss in audio quality. Of course certain amount of discipline is required if you do not want to end up with unnatural sound with a bathroom reverberation. Still, because my room is actually without any issues as far as the imaging is concerned I always preferred the bypassed sound. However, I found out, that when I limit the Stereo Imager function to only the very low octaves (leaving the mids and highs untouched) I can spatialize the soundstage without losing the tinniest bit of focus.The best results I got with the settings somewhere between 1.5 to 2.0 (1 is for the bypassed system) / the music got completely detached from speakers as if the side walls evaporated. In other words - by activating the optimized Stereo Imager the width of the stereo picture expanded by 80cm to each side – enough to recreate the ambience of a small concert stage at home.

Dynamics

The key for correct setting of the dynamic expander is to find the right THRESHOLD value, that is the value from where the limited peaks will be helped to become higher peaks again.If the THRESHOLD is set too low then we are expanding a big part of the audio signal and there is no real benefit. The really dynamic material does not require any treatment, most of the modern music that came out after 2000 is usually squashed to 6dB or lower with no headroom.
The aforementioned Underground of Rebecca Pidgeon shows 16dB peaks that do not touch the 0dB line. With the THRESHOLD set to -5dB and expander set to +3dB the music became more alive and fresh, but it got to clipping values here and there. The good thing was that there was not change to instrumental colours neither I heard any other artifacts that would alter the original score. It seems that the DEQ2496 does its job well.

Well, this was exceptionally well recorded material – how about something that is not that good. The last Motorhead’s album (Motorizer, SPV 916 32) is less impressive. Its dynamic peaks are within only 8dB range and there was no surprise that the music benefited a lot from the Behringer’s treatment. To be honest the only depressive information was the relentless signaling of the clipping-indicating LED. You don’t need to be afraid that you overload the output as this is protected by the Behringer’s internal circuitry but the visual information is quite merciless in its message.
The aural information, on the other hand, was pleasant to my ears. Not that I improved what could not be improved but at least I could listen to the whole album without getting tired after a song or two.

An iceberg

There was an iceberg for Titanic and there is one for the DEQ2496 too. It has generous connectivity options – try to find a standard that the Behringer does not support – but it is an entry level device so the quality of its D/A coverters is not what you require from a high end device. The DACs are approximately at the same level as ones that can be found in CD players within 500 € range. So if you plan to use analog connections then you may be disappointed.

Fortunately there are several digital connection options including AES/EBU ( XLR) and Toslink optics so it easy to bypass the DEQ2496’s DACs and process the signal entirely in the digital domain. Thus the Behringer actually runs as an external DSP processor for the output from a CD player and the D/A conversion can be handled by a dedicated highend DAC. Some players, like Accuphase for instance, also allow to route the signal from the CD transport section to an external DSP and then back to the player’s DAC section. Because parallel to the Behringer review our magazine ran the extensive test of optical cables (look elsewhere on our web for the results) I could test a lot of optical fibre cables, including Nordost Whitelight which I found to be the nicest looking (not sounding as we have found that there are no audible differences between the optical cables for short runs).

All good things come to the end

When I packed the Behringer Ultracurve Pro DEQ2496 in its box and returned it to the dealer I spent some time contemplating whether or not to buy one. Well, maybe it is not expensive enough to be called an “audiophile device” (would that change if its asking price, now at ridiculously low 300€ was higher by the order?) bjut it does what it does with aplomb. Highly rcommended!

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