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Has anyone tried out their digital 24/96 crossover? I am thinking about a pair run as mono 3-ways but frankly, I'm a little leary about going digital at this point in the playback chain.
Vinyl playback will never be the same.......! :rotfl:
I'm interested in hearing from those of you who have neurotic Audiophile tendencies like me.
Charles.
I am absolutely in the digital is not quite here yet camp. It is damn close and at the SACD or high end Meridian level it is great, but as for the inexpensive and probably even expensive pro-audio route, nothing I have heard is there yet. It does the digital part well and I suppose if you used an outboard DAC you could be happy with it, but then you run the risk of jitter and clock problems. My feeling is we need to be patient and it will come.Quote:
Originally posted by Chas
I'm interested in hearing from those of you who have neurotic Audiophile tendencies like me.
Charles.
I am considering using a digital low end for EQ and low pass, but running it parallel and not letting it get in the audio band above say 50-80 Hz.
Widget
Yeah, I think the same as you Mr. Widget. I wouldn't worry if a digital xover was handling something like, say low pass feeding a sub. But, full range I dunno...........?
The thing has some useful features, like EQing a SUB1500 in a small box. My thinking was to use two in mono to triamp the combination of two SUB1500's with my 4333's.
The delay feature might be interesting too.
Sometime someone here is bound to audition one in a monitor set up (rather than a SR application) at some point.
Charles.
I don't have the experience of a Widget, but what I have learnt, and re-learnt again..., with digital is, if it isn't completely out of your price range, it ain't worth considering... :rolleyes:
I am leary too. I have a Behringer 8024 for RTA only. My crossovers and EQ's are analog. It makes no sense to me to digitize SACD/DVD-A or any analog source. Once you do you loose any benefits to be had. Especially with the Hi-Res digital media like SACD/DVD-A. Any experience with the JBL digital crossovers 260/280??
Rob:)
Hello fellow JBL nuts
I just wanted to add some info.
I've been using the DCX2496 a few months now and have also had the opportunity to compare it with other analog, passive and other digital filters.
One needs to recognize a few things when entering into the digital world that really differs from the analog world, to get it right.
Maybe I’m breaking in open doors here, but keeping to these simple guidelines have given me pretty good results and also helped others.
1. Signal levels.
Unlike in the analog world where too much signal causes clip in the digital world the clip normally means heavy distortion due to loss of information. The same goes for to low levels in the digital domain. Especially if you try to run a too low signal into the AD converter, through the DSP to change it and then back to analog again. So, always keep an eye on the levels, not too high but not to low either.
2. Amount of changes in the DSP.
Few of us are using our digital XO only to do the crossover work. We tend to use (over use??) most of the other brilliant trix that it can do. I find that the more I try to have it do the more I lose resolution. These things give us the possibility to go +/- 15 db both with graphical filters and parametrical filters AND stack them. -Things that is completely impossible in the analog world, or at least very difficult. I guess that when stacking these “changes” on top of each other it becomes complicated to realise with out negative consequences. If this is due to too little computing power or bad algorithms I can’t say. On the other hand moderate use of filters gives a excellent result. Don’t try to make a bad system good but rather go for limited improvements in a good system.
3. Do NOT use the built in attenuators.
Most of these filters and DSP gadgets are equipped with built-in volume controls for inputs and outputs. These tend be based upon the cheap built-in VCA’s in the DSP or AD/DA chips or pieces of the actual DSP algorithms rather than high quality stand-alone VCA’s. Probably to keep costs down. These are no good since they sometimes lower the volume by “dropping bits”, hence actually degrading the information. A few high profile players like British BSS and the above-mentioned Meridian seem to use the proper technology with excellent sonical quality as a result. But look at the price tag differences. If you don’t use the built in volume controls but rather the analog controls on the power amp the quality will stay good. There are “real” stand-alone digital volume control units on the market but they are very expensive.
4. Sampling mismatch and possible jitter.
I find the AD portion of the DCX probably being the weakest part. When running analog input with no XO or filters activated there is a small audible difference with the DCX in the loop. Why it’s there or where the difference comes from I can’t say, but it’s there. -Very small and barely measurable but audible all the same. The audible difference is smaller with the DBX Driverack but its there. I guess that it comes from the sheer fact that it takes your analog signal converts it to digital, then up-sample to what ever level the unit uses (DCX uses 24bits@96kHz), then run it through the DSP and then convert it back to analog again. With the Omnidrive unit from BSS there is no audible degrading but they cost 10 times as much.
On the other hand if I use digital inputs (DCX can handle both AES/EBU and SPDIF in) and run it without XO’s activated and no filters it is not audible compared to my reasonable good stand-alone DAC. It’s sonically gone…… :D What that means is that the DA are pretty decent I guess and that the analog circuits on the outputs are OK.
Regarding Jitter it should not be an issue with digital input as the unit locks onto the input signal. I think it can lock on most PCM streams below 24bits@96kHz. As for analog I don’t really have any input.
Now, where does this leave us?
IMHO the digital filters used in a proper way are light years ahead of what can be done with the existing alternatives. As much as 80-85% of the overall sound quality may come from the speakers ability to translate electric impulses to sounds. By using some of the possibilities that comes with entering the digital domain the improvements in sound quality is clear and very present. By using high quality components and good designs, the need for correction is brought down to levels that these units can handle in a good way. Even with the alternatives available I see no way going back to analog equipment for myself. In my room I can get a +/- 2.5db curve from 150Hz to 25k IN MY ACTUAL LISTENING ROOM IN MY CHAIR. 10-15 years ago that was a decent curve in an anechoic chamber. It sounds spectacular.
I’m right now on the look-out for a used Meridian 561 or 568 pre-amp with digital outputs to feed my DCX XO’s. The Meridian is about the only pre that I have seen with digital and analog outs after the DSP = 5.1/7.1 out.
It’s eventually going to be a HT set up so I’m going to use two or possibly three DCX units fed by digital signals. The main speakers are 3-way active, the centre and the rears are 2-way active + 2 subs. With this set up I can keep the signal in the digital domain all the way down from the CD/DVD to the power amps and control all of it trough the Laptop sitting in my listening chair. :D
Hope this may have given a somewhat different view on digital filters.
Best regards
//Robert
"I find the AD portion of the DCX probably being the weakest part. When running analog input with no XO or filters activated there is a small audible difference with the DCX in the loop. Why it’s there or where the difference comes from I can’t say, but it’s there. -Very small and barely measurable but audible all the same."
I think that you summed it up perfectly. In live music, or in a HT environment where there are visual components/distractions, I can live with that "difference", but for pure two channel audio playback, my benchmark, it doesn't cut it.
Last night Johnaec came over and dropped off his newly acquired JBL DSC260A. He is letting me play with it for the next couple of weeks. After giving it a run through, I'll give it a mini review.
Widget
BTW Robert thanks for the thorough overview.
Robert, thanks so much for your insight, I found it very informative. You have confirmed my suspicions about the calibre of the A/D in an under $1,000.00 machine.
It's good to know that if the A/D is bypassed by going digital in, the results are positive.
Thanks again,
Charles.
Hello
Coming from a pro equipment users stand point, the Behringer
or better known as the "B" word equipment is the bottom of the audio barrel. There price does look very attractive but you get what you pay for. People who have tried them say everything from not too bad to they lock up, will not boot up on power up and the list goes on, and your in for a long wait if you need service. Companies such as XTA, DBX, Lake, BSS all make highly
respected digital and analog audio equipment.
For what it is worth I still use 6 analog crossovers in my live sound
PA systems with excellent results, but the digital day will come....
Mike Caldwell
Hello Mike
I think you are absolutely right regarding the older Behringer stuff. These new 2496 series units seems to have been copied from someone with better designs. :D
They also differ electrically and mechanically quite substantially form the older units. The cases are rather well made and would easily stand tour use. The power supplies are of switch type and if one opens the lid they are pretty well shielded.
The electronics also differ. In the newer units (I only know of the DEQ2496 and DCX2496 since I have had both) the PCBs are well made, the digital circuits are typically decent quality, both DA/AD (AKA) and the DSP (AD Shark 32bit floating point). They also seem to have learns the lesson regarding the well-justified critic over the years regarding using cheapo OP amps so in these units they are pretty OK (4580).
Regarding algoritms there is probably som groud to cover. Although Analog Devices are supplying lost of stuff for the Shark as many others (som high profile brands) are using it. I guess that they will keep updating them as they fins new ways of improving. The third FW just got available on their site and it frees up a lot of computing capacity.
Check this huge thread:
http://www.diyaudio.com/forums/showt...threadid=15943
I do not know how it would behave under tour use but I have played around with my unit done all sorts of changes including all possible programming and updated the FW twice without as much a hick-up. For home use it is just fine IF you use the digital inputs. Never had a look-up so far.
I’m going to use three of these things digitally fed in my HT. I will cost me 14 power amps, but hey it seems worth it. :D Power is sexy...
//Robert
Hello
As for the Behringer stuff being copies of other companies
designs, Mackie, Aphex and BSS all suied them and won
for patent violations.
They just came out with a line of power amps that look very
close to the QSC RMX line right down to the style of knobs and the
color of the LEDS, as far as what's inside I have no idea.
As for a good low cost digital processor to try out take a look at
the DBX Drive Rack or the DBX 260.
Mike Caldwell
Hi again.
I think you're right regarding the copy stuff. Wonder what they will do next :D
I have tried the DriveRack and if you are in the analog domain (input and output) it is a better choise, allthough a little more expensive. :)
The drawback is that neither of them have digital input as the Behringer and that is what I need. And the Behringer does sound real good with digital in and 24/48 or 96kHz signal. :rockon1:
Better than the Driverack in analog mode I would say.
The BSS os without doubt the best and most expensive of them. Would not mind three of them.... :biting:
Best reards
//Robert
It’s offered amazing ability at crazy low price and the trade offs aren’t as bad as before with the passive crossover. I can select or experiment with the crossover and the many features to give a smoother sound rather than having my ears obliterated with too high mid range highs.
Dynamic EQ PB/LP/HP
EQ BP/LP/HP
Audio limiters
Time delay
Temperature
Selectable customized crossover filters
Individual barograph display of main and all outputs
All this and more under one bonnet!
It’s an amazing value for a digital crossover in this price range.:applaud: