Thanks for posting this. I also use an RDQ1, and have been leery of the Behringer because I thought it couldn't possibly be as transparent. Can you give more detail on your experience with the auto-EQ?
33 responses Add your response
The auto-eq works by emitting pink noise and measuring it through a microphone. I bought the $50 Behringer mic for this purpose. I then makes a series of adjustments using its 31 band graphic EQ. Although it may measure properly, I prefer the following method (I disable the graphic EQ module and use the Parametric EQ:
I used the Rives Audio Test CD2 with a Radio Shack Sound Level Meter. The Rives Audio CD has a set of corrected tracks that work with this meter. I take the measurements of all the frequencies, and make some initial adjustments with the EQ corresponding to these frequencies. I find this works particularly well to clean up bass modes. I then use my ear to tweak levels to my liking. My preference is to use a shelving filter on the EQ to slightly reduce frequences above 3K or so, and a slightly bumped lower midrange.
Like I mentioned before, I think the Behringer used completely in the digital domain is very transparent, and I cannot tell a difference between it and the RDQ-1. I would imagine (although not confirmed) that the use of the interal DACS would diminish this transparency. I really was not expecting the Behringer to work this well, but as much as I 'wanted' to hear a difference in sound quality (I had a hard time believing the quality/features can be this good for so little money), I cannot as of yet. Although I think I have pretty good ears, others might be able to tell the difference.
I am very curious what other experiences people have had with this unit. If you decide to try it, please report back as to what you think.
I posted a review on the DEC2496. It worked so well for the front channels of my multichannel system, that I bought a second one for the rears.
IMHO, this unit is an example of how pro sound equipment, at reasonable cost, is rapidly approaching high end performance. High end manufacturers may still have a slight advantage, but must realize that the free ride is over.
Smeyers...I used to do the Rives audio disc and RS meter thing. The autoeq feature of the DEQ2496 is much better, and takes about 2 minutes vs an hour. If you don't want flat response, you can set in the "target" response for the autoeq to work to. Also, the "Room Corr" feature provides the high frequency tilt that you mention, and which I also like.
You might be right about the autoeq feature being better... but then again why do you think that? One of the problems I see with the autoeq feature is it's use of the graphic eq for correction. The graphic eq has predefined center frequences which cannot be adjusted. Since there are only 31 of them, it cannot get very precise as to the frequency being adjusted. The parametric eq has a much finer range of adjustments.
I am now trying a combination of auto-eq and additional adjustment by ear. I'm letting the Behringer auto adjust to a flat tonal curve (which uses the graphic eq), then using the parameteric eq to tailer the tone to taste. This seems to work pretty well. It's very cool to be able to save many different profiles, then recall each one to compare to the next. This is a good way to determine what our preference is.
This kind of device is a phenomenally handy "tool" and can also be used to compensate for very poor recordings. The fact that you can save various EQ curves and select them at the flip of a switch is very handy indeed. Got a disc that sounds "digital" i.e. lean and glaring? No problem. Program in the right "correction curve" and you've got a whole new presentation of that specific material. Next disc sounds thick on the bottom and closed in up top? No problem there either. Modern technology hard at work.
Smeyers: Sometimes it's not a matter of having "great" quality parts so much as how those parts are implimented i.e. circuit design. One can use the finest parts in a poor circuit and / or a circuit that is less than optimally laid out ( impedance problems ) and come out worse than a circuit using lower grade parts with better execution. If you check in another thread, i make mention of folks modifying the Behringer's for better sonics. Most of these are basic mods, but like anything else, one can get as "crazy" as they'd like to in terms of how far they want to take these modifications. Sean
Smeyers...The internal A/D and D/A are fine IMHO. To check this out, set the EQ flat, and then compare the EQ output using Bypass mode of the unit. Of course having the option of digital in and out is nice if it suits your system. But, you might consider if the Behringer A/D and D/A could actually be better than other equipment.
The graphic EQ is 1/3 octave, and this works for me. I actually do have an analog parametric equalizer, 7 bands, for my center channel, (which is an identical set of speaker and subwoofer) so I can do a good comparison. The Behringer does a better job, and there is no comparison of the effort required. The parametric Eq settings in my system are all more than 1/3 octave width.
Well, I'm not convinced how well the auto-eq function works. I tried just a few times with and without 'room correction' turned on and off. It just seems to do some wierd stuff in the midrange and treble, leaving the sound somewhat hollow and bright. Maybe the Behringer mic is at fault. I think I would rather have the unit process a sweeping sine wave rather than pink noise, but what do I know. So far I think my ears along with the parametric eq is the best method so far.
The Behringer is a cheap mic, lacks quality control and isn't "flat" according to the published spec's. As such, any / all of the readings that the unit processes is based on the irregular output of the mic that you're using as a reference source. You want better results, get a better mic. Otherwise, what you are trying to do with an uncalibrated, mass produced mic would be equivalent to trying to build a house using a ruler that you "think" has 12 inches to a foot, but really doesn't. Whether or not it is "close enough" will depend on how far off the calibration really is.
Other than that, these types of devices are NOT "cure-all's". They are strictly a band-aid and that's why i said that they are very handy tools. Nothing more, nothing less. One needs to get the system and room dialed in as best possible BEFORE using this type of "error correction". Using this type of approach, the results are FAR superior to just relying on the "band-aid" approach to try and heal the gaping wounds that most systems / rooms suffer from. What has to be done to the room will depend on the room dimensions, speaker placement, speaker dispersion pattern, seated listening position, etc...
Nothing is free and nothing is perfect. Anybody that tells you that a product is perfect or can solve all your problems obviously has something to sell. Sean
Forgot to touch base on this, but the reason that they use pink noise is that it offers simultaneous full spectrum output for time-domain measurements. You can't do that nearly as quickly or effectively when using a frequency sweep. Pink noise is also a far more complex signal, which can cause the speaker & room to respond slightly differently than if it was being excited with a sweeping narrow band signal. Sean
I never thought the product is perfect, nor am I willing to completely rearrange my living room for the sake of perfect sound. I've already taken many steps and have acquired some very good equipment, but need to take some steps to cure some tonality issues without rearranging the room.
As far as the mic is concerned, you certainly might be correct. I do happen to have a Shure SM57 which I'll try out, although I believe since this mic is generally used for vocals, might be tilted a bit in the midrange.
I would guess that the reference mic sold for the Behringer is corrected for in the RTA (that should be the way it works). That has been true of every RTA that I've used. My old standby is an Audio Control 3050A and its reference mic, a C15360. I usually use Alesis digital eq's (two to eight channels). A couple weeks ago I purchased a dBX DriveRack Studio (partly to check out how well the auto eq works) but I'm now waiting for the reference mic (dBX RTA-M) to arrive as it was on backorder. I'd recommend sticking with the mic made for the system.
Danner: I hear ya and understand where you're coming from. The problem is that they can skew the response of the device to compensate for the mic's response, but who's to say that all the cheap mass produced mic's will have the same non-linearities / frequency response abberations to them? As such, if you can find a mic that looks similar to the factory supplied mic in terms of response, but would be more consistent from unit to unit, you'll probably get results that are even more accurate.
Other than that, i've tried contacting Behringer to verify if the circuitry was built for "max linearity" of it has a non-linearity built into it to compensate for the mic that they sell. No response from them on several different attempts.
For the record, i've used a Shure SM-81 with great results. Then again, this mic cost more than any of the Behringer components themselves. In this case though, you get what you pay for. Sean
Danner, you may be right. I just tried a SM57 and what happened is what I thought might happen. Since the SM57 has a somewhat tilted midrange, and not great response at the extremes, the Behringer produced a tonal curve that was severely boosted in the bass and high treble. As it stands now, I'm still trusting my ears!
Smeyers: The Behringer acted as if the system was lacking bass and treble due to the SM-57's lack of extension and corrected accordingly i.e. increased the lows and highs. As such, i would "assume" that the Behringer is taking things in stride in a relatively linear fashion.
This is why i said that the "flatter" the mic is, the more accurate the correction factor will be and vice-versa. That's because the Behringer will correct for the non-linear frequency response that the mic itself introduces into the equation, not what the system / room interface is actually doing.
Compare the results of the SM-81 to that of the SM-57. Now look at the response curve of the ECM8000. You'll have to go to the Behringer website and then click on "spec sheet, PDF 145 kb" to see it though as i can't do a direct link.
As a side note, the response curve Behringer has posted seems to be slightly different from the curve i saw about two years ago or so. As such, they might have changed the mic, changed the spec sheet or both. If the Behrigner ECM8000 actually tests out as this chart shows, and the mics are consistent from mic to mic, it is a tremendous bargain. This is true even if the cost of the mic went up 25% in the last year or so.
One more thing. The ECM8000 is an omni mic. In other words, it picks up relatively evenly in all directions around it. While this may be beneficial in some instances, i don't think that it is here. The Shure SM-81 that i mentioned above is not an omni, but uses a cardiod pattern. That means that it is more sensitive to sounds coming from directly in front of it and off to the sides, but response falls off as you get further behind it. This is somewhat how our hearing works too as our ears act as horns facing slightly forward. Obviously, some folks have larger / smaller ears and some are more stream-lined clinging to the sides of their heads whereas others are more "focused", sticking out and facing more towards their front. This will affect what we hear as individuals and is part of why a machine can only correct for each of our own hearing attributes to a percentage.
Like i said, these devices are great tools, but you've got to learn how to use them. They aren't perfect and you have to be able to interpret the data that they provide and tweak it accordingly to the given installation. Sean
Maril555...A XLR connector can be used for a single ended (unbalanced) signal. My DEQ2496 are single ended in. The unit detects whether the input and/or output is balanced or unbalanced, and adjusts gain to compensate.
Sean...The graph that comes with the Behringer ECM800 mic (which BTW is omnidirectional) looks "flat" to me, although it obviously wasn't drawn with a ruler. There is no broad band of boost or cut that would affect overall sound, and the small deviations that are shown are tiny compared with the frequency aberations (room effects) which the unit is measuring and correcting. Furthermore, these deviations are similar to those of the Shure mics, away from the high and low frequency ranges where the Shure mics are (deliberately) very nonlinear.
Of course it would be nice to design the living room for acoustic properties, but I agee with Smeyers that this is not going to happen. Even Rives audio, of room treatment fame, says that it doesn't work for low frequency problems, where active equalization is needed.
Smeyers...Regardless of what Sean says, the Behringer mic is a calibrated instrumentation mic. If your ears give different results, perhaps you ought to get your ears calibrated. I have just been through the process of having my wife's ears tested and hearing aids "installed". What you are doing with equalization and your audio system is very similar to what the audioligist did when she set up the algorithms in the hearing aids.
I had the Behringer 2496 and the mic in my system for a couple of months. In the end, I found it seriously lacking in transparency and it had a high noise floor. The build quality is just not there, the DACs are cheap, and the PC-based user interface needs work.
The EQ functions are impressive, but the side effects were worse than an unequlaized system. The auto-EQ function didn't work well in my system, but I suspect that the bi-polar radiation pattern of my ribbon speakers caused problems with their algorithms.
The DBX DriveRack EQ products sound much, much better, as about 3 times the price...
Rgodin, have you been able to try the Behringer in pure digital mode without going through the DAC's? I have not tried going through the DAC's, but find the unit to be very tranparent if kept in the digital domain. I cannot hear any difference between this unit and the many times more expensive Z-Systems RDQ1 when used in this manner.
Rgodin...When I was shopping I got turned off on the DBX because of (would you believe) high noise complaints. My Behringer is dead quiet. Maybe yours was defective.
The auto equalization works perfectly, even in the SW range where Behringer suggests that there might be a problem. My three front speakers are bipolar MG1.6, with three colocated SW.
Abrahavt...If you use the DAC in the CDP you have an analog signal, which must be input to the DEQ2496 as an analog signal. If you did not want to use the DAC in the CDP you could input a digital signal to the DEQ2496, and you could take a digital output from the DEQ2496 to some other piece of equipment with a DAC...even to a power amp with provision for digital input.
Lewinskih01, I don't have a DAC so I am stuck with analog for now.
"I am a little disappointed that, while the DEQ does not add colorations per se, it does add a slight haze to everything. Sound is slightly less clear, less crisp, and a bit more shut-in. The haze in analog mode is not as bad as, say, the Creek 4330R's "Mosfet mist". Got rid of the Creek in a hurry May keep the DEQ but still don't like it though."
"Using my CDB's digital output instead, the DEQ2496 DAC sounded horrible. My ear was hurting (like my B&W's) within 5 minutes. Guess I'll have to buy another component :-(, DAC, so I can use the DEQ2496 digitally without its on-board DAC. I think the [enjoythemusic.com] review said there was some loss in analog mode but none digital. Although I can't find the exact quote now."
Paul, is that true even with digital EQ?
Well, I guess my system is resolving then. I tried it 2 ways. First flat EQ with the Behringer in and out of the system. Second using the EQ on my Denon UD-M31 and comparing to the Behringer.
Interesting how the Denon EQ was virtually inaudibly worse. Could be either that it is digital and digital is better or all the wires and XLR/RCA adapters I had to use when hooking up the Behringer.
I use Behringer DCX for crossover, room and speaker correction. Mine is a highly modified unit, but my following comments are for the fully stock version. Although not a 2496 it has similar characteristics.
If used as a DAC it does sound thin, bright and sibilant just as mentioned in an above post. However, if used going analog in allowing both the internal ADC and DAC to work together, it sounds very transparent. In fact the quality is so good that several speaker manufactures use this unit specifically in this way and supply it with their systems.
VMPS is one company, although they also offer modified units. Another is Roger Sanders of Sanders Sound. I had the chance to listen to one of his demos at the RMAF and it was quite good. I had asked him about modifying those units and he told me that there was absolutely no reason to.
All I'm saying is that a stock DCX stuck into a system that didn't have one before - just as an xover, not DAC and no EQ - introducing a quite noticeable loss of fidelity. I've had two completely different but very resolving (and good) systems where this was evident.
(One was based on Supravox field coil driver on open baffles and the other compression-driver horns. SET amps in both cases.)
Never had a modded unit. I have no doubts the right mods could make the unit close to transparent. Because a DEQX is.