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Old 06-06-2005, 04:52 AM   #16
thylantyr

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Originally Posted by RonS
Victor, can you elaborate on your remote control solution? I'm very tempted to go with the AD VCA parts (I have them at hand) but remote control would be a very nice addition to Davey's efforts.


Certainly Ron, - here it is,

My volume control project was motivated by the need to have quite a few channels, - at least 12. You see, my HT has dipole speakers in all 4 corners, - the fronts are 3-way and the rears are 2-way. I use two DCX2496 to control them. So far I need 10 channels, but I may need as many as 16 once I add some subwoofers and possibly side surrounds. I do not use a front center channel.

So, the volume controller must have better then 1% tracking error, have infrared remote capability and can also be used as a kind of balance control, i.e. any combination of channels must be independently controlled. To top it off,- I also wanted to use good old mechanical potentiometers.

In order to solve the tracking problem I needed linear pots. The solution is simple, - turn linear pot in to the log pot by adding a resistor from the wiper to ground. The pot to resistor ratio is about 1:7. So, my pots are 10k linear and I use 1.46k resistor. The parallel combination of the resistor and the pot forces the overall resistance value to be dominated by the 1.46k resistor while giving me a logarithmic law. Also, this resistor can be a high quality 1% unit which goes nicely with one of my compulsions of using good parts whenever possible. In the end all pots are now tracking to better then 1 %.

Next problem was to fix the rotation speed of the pots. The pots I got are Alps 2-channel motorized units and I have 10 of them. You can get them for $3.50US here

http://www.allelectronics.com/cgi-bi...010&type=store

The motors track to within 2 seconds from each other for the full turn. Naturally this is a problem. After all I need at least 3-channel pot for my front speakers and I must have all 3 channels turning together at the same rate. So my solution was to turn 2 channel pot into a 4 channel pot. I place 2 pots back to back and use a shaft connector to bind the shafts together. Now the entire thing acts as one 4-channel pot. Actually because of how those pots are wired internally it becomes only a 3-channel pot, which is also fine for my purposes. All I have to do is wire one of the pots electrically as a mirror image of another. Pairing up the pots also solves the rotational tracking problem to a greatest degree. Additionally the resistors can be used to completely optimize the rotation speed so it is identical for all pots.

Finally, I got a module on the net that give me a motor control with infrared remote using standard Philips codes. I also got a relay switching matrix board that enabled me to activate any or all of the relays with the same remote control. The motor control board gets wired to the potís motors through the relay board.

And here you have it, - out of 10 dual motorized pots I now have five 3-channels pots that I can control independently. No tracking problems at all. All pots rotate with the same speed and show identical resistance with the required logarithmic law. It takes about 40 seconds for a full turn, which makes the control very sensitive.

I know that my approach is kind of out of the left field, but with the overall cost of about $120US I now have what is considered to be a very high quality multi-channel volume control with remote.

The VCA approach is also very credible, particularly with Analog Devices chips. You will have no tracking problems with VCAís and multiple identical channels are possible. The THD of the VCA approach is also low enough. You can easily add a remote control to the VCA design by simply getting a cheap single channel motorized linear pot and an motor control board with remote capability and you are done.



***

re: hiss/noise

... snip ...

This is normal for the DCX. You have to remember that we audiophiles are operating this thing in a totally different configuration than the folks in the pro world. The "fix" is a straightforward concept....you have to get the signal level inside the unit much higher so it's well above the noise. You do this by using a post-DCX multi-channel volume control or adding fixed attenuators of 10-20db on each of the outputs and using a conventional pre-DCX two-channel control.

Also, when constructing XLR-RCA cables (or using adaptors) on the outputs disable the pin 1-3 connection so the DCX doesn't auto-increase the gain by 6db internally.

Some DCX users have noted crackling/noise problems above and beyond this "normal" noise and have traced the problem to a faulty connector(s) on the ribbon cable that connects the rear board to the DSP board.

These are common issues that have been discussed on various forums for the past few years. The DCX is a nice unit, but it's not really Behringers fault that most of the non-professional users out here don't know how to operate it properly.


Cheers,

Davey.



****

Thanks Davey. I'm using AES digital in to the DCX, so no problem with having sufficient levels coming into the unit. I don't find the noise objectionable, in my case I have to move pretty close to the speaker to hear it. At this point I still don't have any post DCX attenuation, so I'm running the digital input at -15dB. I had thought that that was the cause of the hiss, so I wasn't going to concern myself with it.

Cheers,
Ron


http://www.htguide.com/forum/showthr...hlight=dcx2496

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Old 06-06-2005, 04:57 AM   #17
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re: DIY XLR cables for outputs

You want to cut the wire that shorts pin 1 and 3. Having pins one and 3 open will cause the DCX to have 6 db less gain.
This will improve the system Signal to noise for Consumer audio amplifires, that have more gain than the pro amps.

If the 6db attenuation isn't sufficient, an attenuator on the output can be used. This can consist of a pot / stepped attenuator or a fixed attenuation. I personally haven't found that necessary for my system.

HTH

Doug


OK, I disconnected pin 1 (shield) from pin 3 (-V) on one side. And I do hear a lower noise level. So I'm going to disconnect pin 3 from 1 for all the outputs.

Does this applies to the inputs as well? In other words, should I go ahead disconnect pin 1 from 3 for the inputs?

Thanks,

SBM

****

On the inputs it doesn't matter since there is no internal circuitry to sense a single-ended input.

Davey.



http://www.htguide.com/forum/showthr...hlight=dcx2496
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Old 06-06-2005, 05:00 AM   #18
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Ron/Doug

I disconnected pins 1 from 3 for all outputs. The noise/hiss is lower than before. In addition, I just noticed that each output has a gain control. It can be adjusted to +/-15dB. I increased the gain, and noticed the increased noise. Now I set mine to -10dB. This seemed to help reduce the noise, in addition to disconnecting pins 1 from 3 on all outputs.

Am I doing the right thing, Davey?

Thanks,

SBM
P.S. I'm new to all this stuff; so bear with me if I sound somewhat audiophile illiterate...

****

You're going the right direction. The internal attenuators are operating in the digital domain which is not preferable to analog attenuation...in this case. Ultimately you'd want to perform all the attenuation outside the DCX box. You could add fixed attenuators to each of the six outputs or use a six-channel volume control which how I operate mine. In that case all the noise is effectively "removed" and you won't hear anything from your speakers but silence.

If you're using a digital input (as Ron is) you're fairly limited in how to implement a proper volume control without using a six-channel type.

Make sense?

Davey.

****

Yeah, I wouldn't buy commercial attenuators, but you can easily put a few resistors inside an XLR connector or a little box for just a few dollars. Until you get a multi-channel volume control that would be the way to go.

Davey.


****

http://www.htguide.com/forum/showthr...hlight=dcx2496
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Old 06-06-2005, 05:01 AM   #19
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/// I wonder how much of this is audible vs. theory? \\\

We shall see Mr. Frodo
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Old 06-06-2005, 05:36 AM   #20
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/// DIYaudio.com babble ///

Post #69
awolf,

You need to ensure that a fairly large signal is presented at the analog inputs of the DCX2496 in order to maximize its S/N. If you look at the specs, it says there that 22 dBu is a max input level. It would seem that around 10 V is what you need to aim for. However, since DCX2496 is a unity gain device, such a huge input would create all kinds of problems, like the once you are talking about.

When it comes to the digital input, I would imagine you are using the SPDI/F, the level does not really matter as long as it is within specs. However, that still may appear to be too loud.

You need a multi-channel volume control placed after the DCX2496 and you also need a line level amplifier to boost the input signal to the required levels. If you do that, then expected S/N of the Behringer is 113 dB and that is better then the 16 bits you are getting, and that on a good day, from your CD or SACD. So DCX2496 should be fine. I am waiting for mine along with the DEQ2496. By the way I think that 113 dB is an A-weighted value, so in the real world that number must be lower, but still most likely better then 16 bits.

Multi-channel volume is a tricky project, but I just read the Apox thread and am quite impressed. I just might make one for my HT system here. I will need to control two 3-way channels (the fronts), two 2-way channels (the rears), and two single channels (center and the sub). So a total of 12 lines. Iíll need 6 boards and it is possible with Apox design. Each board can be individually controlled, - nice.

Vadim



****


/////////// funny //////////

I have two units and I do not regret buying them.
From my point of view the D/A section is not so bad. I coud point a couple of "proffessional" devices here, costing several K, that sound worse.
What I did was, like previously suggested by another poster, cleaning the supplys, adding decoupling capacitors and that improved the sound a bit.
I;m happy with the units but I'm ready to jump and do any mods to improve them.
How difficult would be to get the schematics? Do Behringer sells a "tech manual" or something like that?



same guy later;


Right now is running from the SMPS. I did a fast swap with a linear supply and didn't notice any improvement. Granted, that linear supply was a very simple one, with 3 leg regulators and a few bypass caps (pretty basic), so I returned to the midly modified original SMPS.
I'd really like to get some schematics for this unit in order to do a more in deepth mod.



/// so he tries a linear powersupply to replace the switch mode power supply and hears no difference ////


Cheers! for inaudible mods!


http://www.diyaudio.com/forums/showt...0&pagenumber=9

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Old 06-06-2005, 06:02 AM   #21
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Hi

I just receive this new wonder - DCX2496, but have problems with the levels.
I use it with the digital input on A directly from the digital output from a Teac vrds 10.
Most of the times the level meters go up in the red on the inputs and on the outputs I have to lower the level up to 9 dBs before clipping.
My questions is how do others use the digital input and is it possible to lower the digital level?

br


****

br,

For digital input you can use the input sliders to reduce the level if required. It can be a bit confusing however because the level indicators don't reflect this change and might still be bouncing up into the red even though the unit is not clipping internally.

If you have any equalization programmed that is boosting levels above 0db then you risk clipping. I would suggest set the input sliders no higher than -3db, and even lower if there is some EQ boost programmed. The clipping indicators may still be flashing, but it's probably okay. You need an oscilloscope and test CD with some 0dFS recorded tracks to really confirm this.

RCA/XLR adaptors are available from many outlets for cheap. Check MCMelectronics.com.

Some of the Behringer units adjust the gain automatically if using unbalanced interfaces so there really isn't any penalty for doing this. The 12db reduction in SN ratio mentioned by Ric is actually a different subject. Pro units generally operate at a level 12db higher than consumer units. It's good to take advantage of this extra headroom if you can, but if it means interfacing with transformers and/or outboard active devices it's probably not worth the trouble.

The most important thing to consider with the DCX is volume control implementation. If you're using a digital input then you need a good quality four/six channel attenuator or VCA or something similar.

Cheers,

Davey.



http://www.diyaudio.com/forums/showt...&pagenumber=11
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Old 06-06-2005, 06:21 AM   #22
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This thing has now confused the **** out of me
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Old 06-06-2005, 07:20 AM   #23
thylantyr

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Quote:
Originally Posted by madpoet
This thing has now confused the **** out of me


I'm going to do the simple test, analog in and drive my
Adcom with the XLR to RCA cable, and test it, also try it
with the -6dB gain on the output to hear if I get less noise. The QSC amp will run balanced, XLR to XLR.

I will try it with a weak source and a stronger preout voltage {source}, I have a preamp with adjustable gain I
can use.

Later, I need to buy a real CD player to try the digital outputs.

I did a preliminary test using a single NSB with my preamp
and I didn't hear anything weird.

I think many folks are trying to operate their unit at the
extreme ideal conditions.
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Old 06-06-2005, 07:31 AM   #24
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// back to data collecting //

DEQ2496
Received mine to convert analog to AES/EBU for testing some boards. I have three Audio Precisions in my lab. THD+N is in the area of .005%. Am very happy with the performance and sound quality.

Tho SHARC AD21065 DSPs in it as well as mostly AKM A/D and D/A converters, far better than consumer gear uses. Loads of features too.


__________________
Dan Fraser



****

Anyway...
The more I think about how the unit works internally, the more I realize I do not have a clue about it.
The only thing I'm completely sure is that I'm using it alongside pro gear that cost +30K and it is sounding ok. Could it be improved? You bet. But in the mean time is working just right.
Today I put capacitors between my gainclones and the 2496 to take care of the 10 mv offset at the outputs. Also I'm working into band-limiting each band with R-C networks and that is sounding outstanding.
I think is key here to manage the levels right, trying to use every bit of resolution. I'm also attenuating the signal directly at the input of the amplifiers -hitting the input of the crossover as hot as the headroom lets me-and that helps too.

Ric



//// $30,000 pro gear vs. the $250 Behringer .... hehehe ///


***


I'm using the behringer with Urei coaxial speakers that I'm modifying.(I added a super-tweeter so they are 3 way speakers now) .

I can not insist enought how important is to use the full resolution of the unit, otherwise you'll get a grainy and veiled sound.
Last night I went to a friend's house that was blaming his unit for grainy sound. When I arrived I noticed he was injecting a -10db signal into it, And also the volume was in the preamplifier, BEFORE the Behringer. So most of the time, the signal meters of the unit were barely lit. That's too low a signal. You'll loose resolution, and in digital that's a no-no. The cure was to inject a healty signal thru it and then, attenuate the output with a passive potentiometer between the output of the Eq and the input of the power amp. The sound was great after that. He couldn't believe it.

Currently I'm using 6 gainclones after the Behringer. They have a gain of 22 times, so injecting a +4db at the amps inputs is way to hot. I could lower the gain of the amps but this is not recommended.Sound suffers.
The solution was to add internally a couple of resistors to atenuate the signal (14 db in my case) and now I can use most of the resolution of the unit. The sound is clearer, no hiss or noise.
I think the Rane unit is better, but at the price of the Behringer, I'd say is money well spent.
I'm still testing my new triamplified speakers+Behringer+GClones combiination. I still have problems at the crossover points and I couldn't make the phase control do anything meaninfull. Also, the auto align feature does not work propely, but otherwise everything else is great.


cheers

Ric



****

Bonjour Jean,

This entire thing about proper levels is simpler than it seems to be.

I understand what you want to do: Your audio chain would be:
Preamp with volume control->Behringer->Amp.

That would work reasonably good, but is better if you can send to the Behringer a hot signal at all times and put some kind of volume control after the crossover.
Thereís a thread at this site about the DIY Apox volume control kit that you could consider. Many people have built it and they are happy.

If you can compromise somewhat, you can live with the volume control BEFORE the crossover, like I do.
BUT if you do so, youíll have to optimize the levels in your audio chain. How do you optimize?

1-Make sure the output of the preamplifier is hot enough for the crossover. Most likely, your Rotel is a Ė10 device with RCA outs, right? Letís assume it is. So the signal that outputs is a bit low for the 2496, which is a +4 device (Actually, almost 12 db low!). You need to amplify the signal at least 4 times (11.8 db). If you fail to do so, your signal to noise ratio will be worse in exactly 12 db! And you also loose those 12 dbs of resolution.
Would you dare to modify the output stage of your preamp?

2-After the Crossover you are going directly to the power amps, right? I assume that your system:Pream+ crossover+ power amps are all close together, right? So you do not need balanced lines. You just use pin 2 and 1 on the XLR out of the Behringer and go unbalanced to the amp.
Are they consumer devices (-10) or pro devices (+4)? If they are expecting a Ė10 signal, you need to provide attenuation; this can be done cleanly with a couple of resistors at the input connector of every amp. You do not even need to open them, Give me more detail of your amp and I can suggest the resistor values.

In a few hours Iím leaving on summer vacations. Iíll return by the end of January, if you have any questions Iíll be more than happy to answer them in a few days.

Cheers

Ric



http://www.diyaudio.com/forums/showt...&pagenumber=15
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Old 06-06-2005, 07:53 AM   #25
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// DIYaudio is down, off to Audio Circle I go ///

Thread: Behringer DCX2496 DAC sound quality?

I've been shopping around for a reasonably-priced decent-quality external DAC, and I've also been toying with the idea of digital crossovers and bi- or tri-amping. The Behringer DCX2496 appears to offer everything that I've been looking for in a fairly cheap package (under $300) -- it offers analog and digital inputs and six analog outputs. Here's what I'm thinking:

1. As a "normal" external DAC -- I hook up my digital source to the digital input and set the first two outputs to full range. I can then hook up my stereo pre-amp to the first two outputs.

2. As an external DAC and crossover -- I hook up my digital source to the digital input and use two pairs of outputs. I can set the crossover to have one pair of outputs be high frequency and the other be low. I then drive four channels of amplification and bi-amp my speakers.

I'm pretty sure that both of these scenarios would work, but the big question is, "is it worth it?". How does the scenario 1 compare to using a comparably priced external DAC? Being able to play around with a digital crossover is a nice-to-have feature, but if the audio quality of the DAC isn't as good as a regular external DAC, I'd probably be happier with the DAC. Any opinions?

By the way, the external DACs that I'm considering are:
- Scott Nixon Chibi DAC or TubeDAC+
- M-Audio SuperDAC 2496
- ART DI/O
- diyparadise.com Monica2
- Channel Islands VDA-1

Have I missed any decent sub-$500 external DACs that are worth considering?

-Rob



****

The DAC in my Behringer DEQ2496 is excellent sounding. Enough so that it has replaced my (unmodded) ART DI/O. I think we're learning from the wave of cheap digital amps and receivers everyone seems to be raving about that just because something doesn't cost an arm and a leg doesn't mean it can't sound excellent. I purchased mine from Musician's Friend which has a 45 day money back policy. Just give the DAC some time to break in.

Tweaker


****

I went from the stock DAC in an entry level denon DVD player to a behringer deq2496, to a CIaudio. The denon and the behringer sounded very similar, the CI was noticeably better. Mostly in the detail and seperation of the soundfield, and focus of the image, for lack of better words. Granted, the behringer was new and the CI was well broken in.

Ryan


****

The Behringer, like any component, will take some time to sound it's best. Don't judge the sound new. For the money, especially considering what else you get, I think it's very good. Probably not a giant killer, but very good. Not surpised to hear that the CI DAC is better sounding, though. They make good stuff.

Tweaker




****

I haven't tried it with as you described but I have read numerous posts over at the Audio Asylum of people using it that way and seeming to have good results. One thing I would not recommend is using the optical input (true with any DA). A good coax sounds much better. The way I have mine set up is transport to a GW Labs DSP (with a coax), which does do some jitter removal, and then I use the balanced outputs of the DSP (with a balanced digital cable) to the Behringer. The DSP converts from 75 ohm to 110 ohm. Keep in mind that the Behringer has XLR connections which are 110 ohm balanced. Chances are your transports output is 75 ohms. That might not produce the best sound that the Behringer is capable of. There is an inexpensive solution, though that will do the conversion and remove jitter without spending the money on a GW Labs or Monarchy DSP. It's also made by Behringer and can be purchase for about $69.00 at Musicians Friend. (I'm starting to sound like a shill for them, aren't I?)

Tweaker



****

I can't say how the DAC compares to others because I haven't used it except as a digital crossover. I've noticed an excellent improvement in clarity since I removed the passive networks in my speakers and started using the Behringer. For me it was definitly worth it. I can't say what will happen with other speakers and amps.

Timbley



http://www.audiocircle.com/circles/v...hlight=dcx2496


/// Fyi, I don't believe in the equipment 'break-in' BS, a form of audio voodoo ///

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Old 06-06-2005, 08:01 AM   #26
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Thread: DEQX,TacT, and DSP

fyi, the DEQX is an interesting piece;

http://www.e-speakers.com/products/deqx-new.html

Price is ~3,000 - $3,750

//// An interesting comment from Davey, who seems to
be the internet resident 'guru' on the DCX ///


John,

Most of those six DEQX advantages can be pretty much achieved by much cheaper DSP-based crossovers in conjunction with a integrated or separate parametric EQ unit. Manually of course, and with much tediousness and no fancy Windows GUI.

1. "Lowering distortion" is a broad statement. I assume you mean distortion reduction related to the steeper filter slopes. This would be true, but steeper slopes than 24db/octave electrical reach a point of diminishing returns rather quickly. A 300db/octave crossover doesn't really have any advantage (distortion-reduction-wise) over a 48db/octave crossover. Reduction of driver linear distortion for out-of-band issues would fall into that category, but driver non-linear distortion can't be improved with this or any other crossover.

2. "Increasing dispersion" is an interesting statement. I would like you to explain how the DEQX can increase dispersion (in a good way, and relative to another active crossover option with steepish slopes) by shaping of the frequency response curves and filter slopes.

3. "FR correction" is possible with many DSP-based parametric EQ units that have multiple bands. For example, the Behringer DSP1124P has 12 adjustable parametric filters per channel. (Ruler-flat frequency response is not necessary anyway.)

4. "Time/phase." Time alignment (of each filter section) is possible with any of the current DSP-based crossovers. "Phase alignment" or "phase shift" or "linear-phase" or whatever you want to call it (related to FIR-based crossovers) still doesn't have any audible advantages in my (or many others) opinion. There have been some interesting experiments along these lines and in all cases listeners have not been able to identify an audible difference....assuming the testing scenario is valid. I have an interesting test for this that you might like to challenge yourself with sometime.

5. "Room correction." Same as FR correction and time alignment used together....kind of. Also, I hope you understand room correction is only valid at a single (listening) point in space.

6. "No lossy crossover." Yep, but no advantage over any active line-level crossover system.

So, as an example, a Behringer DCX2496 used in conjunction with a Behringer DEQ2496 could provide 95% of the capability of the DEQX at about 15% of the cost. These types of units (albeit at higher cost than the Behringers) have been available to folks in the prosound world for many years. In many ways those folks are light years ahead of the "audiophile" manufacturers. Please check out some of the many units from Rane, BSS, XTA, Driverack, Ashley, etc, etc.

Also, there are a number of advantages that analog active crossovers have over any digital units, but that's a topic for a different thread.

Cheers,

Davey.



****

Well, I'm going to disagree with this somewhat. 75-80% in a well executed implementation maybe, but not 95. The FIR filter capability of the DEQX really is a differentiator. I have been playing around with DSP xover/correction techniques for a while using a PC, and the IIR approach used by Behringer etc is just limited in ways that a *well conceived* set of FIR filters isn't. Particularly in the room correction domain, a parametric eq is just not the same thing as FIR correction.

Of course, the FIR is much harder to get right, but when done correctly it really puts things into a different league. A poorly implemented FIR approach can easily be *worse* than a well-tailored IIR approach, though, so it certainly is not a panacea.



dwk

****

Maybe we should start a new thread with Davey's post as the questions of discussion as I have a few questions of my own on these matters.

As far as Behringer vs. TACT or DEQX is concerned it seems as though the Behringer "as is, or off the shelf" has a few less than stellar qualities about it related to manufacturing for a price point. So far as I know, those who say "there is no comparison" have done nothing to address the few simple things that the DIY community has talked about for some time now to really make the Behringer perform in line with the big boys.

Davey I know has designed a 6ch VCA volume control (in the analog domain) that he shared with me that allows for the volume to be done, not in the Behringer which apparent the Behringer isn't very good at. *Thanks Davey for sharing your design, I still need to find some time to mock it up*. That is one of the first things that can be done and relatively inexpensively (~$250 to make the 6ch VCA). Issue #2 involves tackling a few issues with the PSU, such as adding a little extra filtering. #3 is admittingly a little less straight forward but doesn't sound too intimidating to novice DIYer such as myself, and that is cleaning up the S/PDIF incoming signal and correctly loading the signal. Those who I have read that have done these few simple things have reported excellent results, whereas before they said the units were lackluster.

I know that even a few TACT owners has discussed the need to do #2 above to their units to make it perform top notch, so even these product supposedly in a 'completely different class' are not without some of the same problems. My only problem is unless the more expensive products have some 'killer ap' that can't be done with the cheaper products and a little bit of research and work then I don't see the point.
_________________
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Some back and forth debates after this...

Last edited by thylantyr; 06-06-2005 at 08:04 AM.
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Old 06-06-2005, 08:11 AM   #27
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... continued


Hey folks, Roger here, I finally got a chance to get on and read through the thread (don't do too much surfing)and thought I would put in my 2 cents on behringer vs. DEQX. I used the combo of the Behringer DEQ and DCX from about June '03 until January '04, this was with a pair of dipole line arrays using 8 of the 5.25 pinchusion frame seas excels per side (basically the same as the 6" excel) coupled with a 45" newform ribbon and that time (dont laugh) a pair of Yamaha powered subs, now I have Linkwitz style dipole subs with the Peerless XLS drivers (2 per cabinet).

To compare the behringer combo with the DEQX I set up the DEQX to feed the same amplifier (a modified Panny XR-45) with basically the same settings in the DEQX as had been loaded in the DCX and using analog out of the DEQX. I will preface this with a short statement, of course people want to beleive that they made a good choice, but honestly I had already gone through the whole learning process of the DEQ and DCX and was really of the opinion that if it didn't improve the sound "enough" I would sell the DEQX. Drum roll please, to use Daveys analysis, I think using analog out on the DEQX as the comparison, the behringer delivers about 73.25% of the sound quality of the DEQX for of course a lot less money.

I won't wax eloquenlty about the differences, but basically there is just more inner detail and information with the DEQX, individual instruments just stood out more, especially percussive instruments down in the mix. Don't get me wrong, the behringer stuff can make a big improvement compared to a passive crossover, and as a stand alone setup doesn't do anything bad, there is just more there with the DEQX. I only ran my arrays with passive for a short time since it was a compromised solution because of efficiency differences between the midrange array and the ribbons before I went with the behringer stuff.

I really wanted to drive 3 modified panny XR-45's with digital signals and looked into modifying the behringer for digital out, but it was going to be too involved, so the deqx I bought has the digital out option, and setting the sytem up that way was the next change in the systemthat was the next change in the system.

Last thing about Behringer vs DEQX, as Rick pointed out the DEQX is very flexible, but that also means that it is somewhat more complicated than the behringer, but ultimatley I think it has more to offer if money isn't a problem and one is willing to take the time to learn the features and use it fully, it's more of an audiophile product whereas the behringer is geared much more toward the pro sound crowd and is a little difficult to integrate into a homeaudio system although Davey has done some great work with his 6 channel volume control.

Roger
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Old 06-06-2005, 08:21 AM   #28
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thread: I got a Behringer DCX2496 crossover


I'm using it wih my Panasonic SA-XR50 to bi-amp my Klipsch RF-7s, inspired by the folks at Newform, and it really is a huge upgrade over using passive crossovers. I'm also using the DEQ2496 with the calibrated microphone, which I found indispensable for getting the speakers EQ'd. The passive crossovers were doing a pretty impressive job at creating fairly flat response from drivers that aren't very flat.

"Caps coils and resistors, you did a fine job, but from now on you must stay away from my speakers!"

If any of you have been thinking of trying this setup, I heartily recommend that you do. Getting everyhing EQ'd correctly takes some patience. But once you get it set up right, the sound is improved in just about every way.

timbley


****

I've got a DEQ2496, EQ but no XO, but digital I/O. I found it hard to EQ with just the behringer, the resolutions not all that great. I just got hooked up with true rta, what a difference. 1/24 per octave resolution lets you use the parametric EQ rather than the graphic. Software $100, new soundcard $30, mic preamp $50, and a couple of cheap cables from the shack. If the DCX has parametric EQ's, it's worth it.

Ryan


****

True RTA sounds very interesting. The DCX does have parametric EQ. Strangely, I find it very difficult to get good result with the parametric unless I'm going after a spike. For general curve shaping, I have a much easier time with the 31 band graphic EQ on the DEQ.

timbley


****

In the behringers, all EQ and XO are done in the digital domain. You don't have the phase shifts and other nasties associated with analog EQ's. I know DEQX also has phase correction and I'm sure better DAC's. I used the DAC in my DEQ2496, no XO, and it sounded similar to the entry level denon DVD I was using as a transport. When I add a CIaudio DAC, there was a big improvement. Bigger soundstage, better imaging. I'd love to go with the DCX2496, includes XO, but it only has analog out. Still looking for a budget EQ/XO with digital I/O.

Ryan



****

How is this so? I don't think Behringer claims this. FIR filters are ones that are suppose to be phase linear, not the IIRs done in Behringer. IIRs still do the same phase shifts as regular analog xos.
_________________
Josh


****

Yep, that is true. The phase shifts associated with the crossovers and EQ's in the DCX2496 are exactly the same as analog equivalents.

Cheers,

Davey.
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Old 06-06-2005, 08:27 AM   #29
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thread: DBX DriveRack vs. Behringer DCX2496

Has anybody compared these units?

I am looking for a crossover and parametric eq for my VMPS Larger subs.

Thanks,

George


****

everyone says to get the dbx over the behringer. the behringer is the rock bottom cheapest. on the other hand, i heard one guy at audioasylum had a driverack 260 and dcx2496 and couldn't hear the difference b/t the two so he sold the DR260.

i have the Driverack PA. it's a great unit. are your other pieces XLR? or will you have to get XLR to RCA cables?

mike


****

Mon Jul 05, 2004 5:41 pm

--------------------------------------------------------------------------------

Mike,

My amps are balanced and my preamp is balanced out only as well.

How is ease of use on the Driverack?

George



****

extremely easy. there's no problem in that dept. you should have it all understood the first day. you should like how easy it is to set-up. is it just gonna be a lp x-over? or maybe band-passed. 18-70hz, for example. it has a feature for managing subwoofers. something about making them less boomy, if necessay, and other stuff. that's all in the sub-harmonic synthesizer program.

when considering digital pieces, do people ever give consideration to the DAC inside?

mike


****

$499 w/ a free mic

Mine works great. I have done an A/B with and w/o the driverack. The driverack does not adversely affect the sound. With EQ and X over the sound is awesome

bingentio


http://www.musiciansbuy.com/mb/item....OVMTC=standard


****


... snip


Most digital EQ manual definitely states you have to switch power amp off before you cycle the EQ or you can damage the speakers.

Concerning the Driverack I've tried it and definitely did not like it. It was quiet, but as soon as the music played there was a definite haze of noise behind the music. True, I've used it for extreme freqs ( e.g 40Hz low pass) so it could be the accumulated rounding errors.

I've build a direct i2s I/O for it, but it did not help, the noise remained.

I still prefer the older DSPs uising 48 bit fixed point algorytms (EV, RANE) to the newer floating point ones.

Csero




http://www.audiocircle.com/circles/v...hlight=dcx2496
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Old 06-06-2005, 08:30 AM   #30
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re: Behringer


Behringer has a few new models that have a 31 band EQ with the feedback destroyer that can even act as a DAC. Do any of you have experience with any of the newer models and whether they would be good as either an active crossover for a two way speaker or as a crossover for passive subs powered by say a Crown amp?

The ULTRAGRAPH DIGITAL DEQ1024 seems the best but the ULTRAGRAPH PRO FBQ6200 might also be good.

Any opinions?

Krister



****


Hi Krister,
Just saw your message.
I use the DCX2496 with great success on my upper echelon speaker systems.
The DCX is your best choice for active crossover duty, WITH EQ. You will eventually learn that 31 bands is not necessary for proper EQ. In my reference system I use just 3 EQ's: trap a single room mode in the bass, use another for overall bass level, and a PEQ in the mid treble.
Have a look at my site for more inside info on DCX real-world applications.
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