Speaking of gain, I've been wondering what the overall voltage gain of my system is.
So I measured it. I chose the output of the AKM chip as 0dB (the source) and the terminals of the drivers as the destination. This includes gain adjustment at the amps (volume control) and the L-Pad on the horns.
For the bass section my overall gain is about 9dB.
For highs and mids - minus 6dB.
I would consider that pretty low gain.
So I measured it. I chose the output of the AKM chip as 0dB (the source) and the terminals of the drivers as the destination. This includes gain adjustment at the amps (volume control) and the L-Pad on the horns.
For the bass section my overall gain is about 9dB.
For highs and mids - minus 6dB.
I would consider that pretty low gain.
User-reviews: Behringer Ultradrive PRO DCX2496 - Audiofanzine
Is there any credibility to this review?? I am looking for this unit as an alternative to an active xo, saving me lot of trouble.
Is there any credibility to this review?? I am looking for this unit as an alternative to an active xo, saving me lot of trouble.
That review is maybe done by some DBX's or some other competing firm's stock holder
Is is so full of total bull shite.You can simulate free prosessor power with the software found from the Behringer's website (scroll down). BEHRINGER: DCX2496
With 3-way stereo Linwitz-Relay 48dB config, (x-over points set to 100 and 3000) you will still have 24% of free prosessor power available. (Rememeber that you will not want to use hi-pass for the woofer nor low-pass for the tweeter.)
With 24% of free power one can set approx 24 parametrit EQs.
One can place 9 EQs per each input and each output. After setting EQ no. 1 you have to change the number to 2, and after setting that you have to set the number to 3 etc. This was missed out by the dumb joker who left that mentioned "review" since he stated that he could place only one EQ per input or output
. User's manual is the key to success, but even without it DCX is quite intuitive and you need nothing but general IQ to operate it.X-overs work Exactly as they should, they do not just "attenuate the signal couple of dBs" like was stated at your link (Quote: "The crossover filters are not very effective: they don't really cut the frequency spectrum (they only attenuate a couple dBs) and the slope displayed is not correct.") Also this statement is pure rubbish. X-overs have been tested to work perfectly correct. This test I'm referring to was linked something like 15-10 pages back in this same thread. Test was written in Germany, but google translate helps.
DCX2496 is absolutely fantastic piece of equipment. Don't buy that mentioned "review", which was purely designated to give DCX a bad reputation. The review was even done in 2009 with the newest DCX version! It is total crap from the start to the end.
EDIT: Here's the test, it was on page 215. Quite an expansive thread
: http://www.soundmaennchen.host.sk/Messungen/Ultradrive/Ultradrive.htm ... or Google translate: http://translate.google.com/transla...ungen/Ultradrive/Ultradrive.htm&sl=auto&tl=en
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Wow! That is (mostly) a ridiculous review. Besides his obvious lack of familiarity with the product, I wonder if there was also something wrong with the unit he tested. I'm running Magnepan Tympani IV's with my DCX. The bass panels are crossed in between 40Hz and 401Hz, however, Maggie bass panels are nearly full range in their capability for higher frequencies. If the crossover was "only attenuating a couple of dB", I would certanily hear it. Vice versa, if the bass weren't cut properly to the midrange panel, I would have blown fuses or the panel very quickly indeed.
The only thing I agree with is his statement that you can't pick exact frequencies. I imagine that's something to do with the algorithms used for crossover calculations. But, seriously, why is he hung up that he'd have to pick a frequency that's within 1% of his target, but not exact. The same corner will be available for both high and low pass, and I don't believe at all that anyone is going to be able to tell the difference between a 24dB/octave crossover at 400Hz and the same one at 401Hz. As for the CPU power, I've still got some left over running 4 parametric EQ's and a three way 24dB setup plus summing of sub. In his defence, I will note that one of the DCX firmware updates was to allow for more available CPU processing. Maybe his unit had an early firmware revision installed.
If you buy the DCX from someplace like Zzounds, you get a pretty long, no questions asked, return for refund policy. You really don't have anything to lose trying it out, and I'm pretty sure you'll like it. FWIW, on mine the sound is reliable and good. The only thing that's not reliable are the front panel level LEDs, which stop lighting after the unit has been on for a few weeks. Power cycling it will then make them start working again. Still, this is just cosmetic, even without the meter LEDs, the crossover functions are correct. It's actually even a bit ironic, in that, on the Yahoo DCX forum, there was one guy who's project goal was to permanently disable the LEDs, which were bugging him.
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Has anyone tried Behringer's Ultramatch Pro SRC249 - BEHRINGER: SRC2496 - in front of the DCX?
With this in between pre amp and DCX one would get volume control and digital input to DCX. And it is quite cheap. I have to consider this option.
Any opinions or user experiences?
With this in between pre amp and DCX one would get volume control and digital input to DCX. And it is quite cheap. I have to consider this option.
Any opinions or user experiences?
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Behringer SRC2496 and DEQ in front of your DCX
I use a Behringer SRC2496 and a DEQ in front of my DCX in a digital chain. Well actually, I'm in between active cross projects for the last couple years while I have been working on developing various diy amplifiers which is easier when running my speakers with the passive crossover, so I have been using the direct out modified DEQ as my digital source but the SRC is useful in front of the DCX as well.
Since I run my main volume control at the amps and the modified DEQ/DCX doesn't have the high gain problems of the stock units, I like the SRC2496 for analog in as it has a level control that the other units lack - so as to accept the analog from the source with no preamp and properly saturate the ADCs into full resolution. I have switched to internet radio and don't play my turntable much anymore so the analog in isn't used much, only for tv once in a while or if somebody wants to play something off of their phone.
I normally play all my music from the digital out of a laptop/ M-Audio FireWire 410 digital in to the SRC for upsampling and then digital out. The upsampling actually works wonders with the DEQ, with 24/88.2 sounding noticeably deeper and more delicate. Better than 24/96 for some reason and much better than the straight,"external clock" pass through setting with either the 410 or my EAD T1000 transport. With the DCX, the differences that the SRC make with digital in are smaller and seem to favor the 24/96 over the 88.2 and the pass through only slightly. But for the price it is a very cool piece of gear and looks super trick sitting under the DEQ and DCX in a stack!
I have found some really transparent, cheap, digital cable, the twisted pairs pulled from Belden 1701A, to make my digital cables out of, so there is no draw back to running the digital stack. It's only a few bucks for the cables. The DEQ makes putting the final dashes of room EQ into your active cross (or passive cross) so much easier with it's graphic EQ and you may even find that you like a little stereo widening/balance and dynamic expansion.
For some reason, many DCX users take offense to the mention of the DEQ as being redundant but I find the graphic EQ more intuitive for fine adjustments. The SRC2496 also has a decent headphone amp built in which I use at night and would be worth most of the cost by it's self.
I use a Behringer SRC2496 and a DEQ in front of my DCX in a digital chain. Well actually, I'm in between active cross projects for the last couple years while I have been working on developing various diy amplifiers which is easier when running my speakers with the passive crossover, so I have been using the direct out modified DEQ as my digital source but the SRC is useful in front of the DCX as well.
Since I run my main volume control at the amps and the modified DEQ/DCX doesn't have the high gain problems of the stock units, I like the SRC2496 for analog in as it has a level control that the other units lack - so as to accept the analog from the source with no preamp and properly saturate the ADCs into full resolution. I have switched to internet radio and don't play my turntable much anymore so the analog in isn't used much, only for tv once in a while or if somebody wants to play something off of their phone.
I normally play all my music from the digital out of a laptop/ M-Audio FireWire 410 digital in to the SRC for upsampling and then digital out. The upsampling actually works wonders with the DEQ, with 24/88.2 sounding noticeably deeper and more delicate. Better than 24/96 for some reason and much better than the straight,"external clock" pass through setting with either the 410 or my EAD T1000 transport. With the DCX, the differences that the SRC make with digital in are smaller and seem to favor the 24/96 over the 88.2 and the pass through only slightly. But for the price it is a very cool piece of gear and looks super trick sitting under the DEQ and DCX in a stack!
I have found some really transparent, cheap, digital cable, the twisted pairs pulled from Belden 1701A, to make my digital cables out of, so there is no draw back to running the digital stack. It's only a few bucks for the cables. The DEQ makes putting the final dashes of room EQ into your active cross (or passive cross) so much easier with it's graphic EQ and you may even find that you like a little stereo widening/balance and dynamic expansion.
For some reason, many DCX users take offense to the mention of the DEQ as being redundant but I find the graphic EQ more intuitive for fine adjustments. The SRC2496 also has a decent headphone amp built in which I use at night and would be worth most of the cost by it's self.
How it would work in a chain where 1) analog signal is taken from preamp to SRC2496 and from there 2) the signal is taken digitally to DCX and 3) finally from DCX to power amps that don't have gain control?
I will be using 2 DCXs. Is it (in SRC) possible to route the same analog signal to two digital outs or do I have to use some Y-piece in order to be able to pass the signal to those two DCXs?
edit: what ADC and DAC is used is SRC? I saw from user's manual that they are also AK's chips, are they the same that are used in DCX?
I will be using 2 DCXs. Is it (in SRC) possible to route the same analog signal to two digital outs or do I have to use some Y-piece in order to be able to pass the signal to those two DCXs?
edit: what ADC and DAC is used is SRC? I saw from user's manual that they are also AK's chips, are they the same that are used in DCX?
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Any opinions? Considering my setup should I get one SRC so I would be able to give DCX digital signal? I have tested that DCX hisses less with digital input, so am I able to reduce DCX's hiss by digitalizing the signal before DCX with SRC? Or would the hiss be the same to analog inputs because the SRC would also add hiss, and that would negate the benefit of using digital input in DCX?
The best option would be of course a preamp with volume controlled digital output but I don't know any such preamps.
The best option would be of course a preamp with volume controlled digital output but I don't know any such preamps.
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Hi Legis - have you tried to understand what's been said by several people here?
Again - you are wrong in your assumption that the DCX has too much noise (what you hear as hiss when keeping your ear close to the tweeter).
Forget about that !
To put things into perspective you *always* have to relate noise to the signal - the S/N figure you can look up in specs is what you have to understand first.
So again - attenuate both - signal AND noise to the appropriate level by a voltage divider - very simple ...
You already have got guidance about gain structure - just re-read those postings - try it - and then ! come back
Michael
Again - you are wrong in your assumption that the DCX has too much noise (what you hear as hiss when keeping your ear close to the tweeter).
Forget about that !
To put things into perspective you *always* have to relate noise to the signal - the S/N figure you can look up in specs is what you have to understand first.
So again - attenuate both - signal AND noise to the appropriate level by a voltage divider - very simple ...
You already have got guidance about gain structure - just re-read those postings - try it - and then !
come backMichael
After trying a stock DCX, and found it noisy (in 112dB efficient horns!), I bought a dbx DriveRack 260. Just as noisy. Did the full DIY-routine, swapped all opamps to LM4562 (big handfull), some coupling-caps, to BG, and it did sound slightly better, but hardly worth the effort. And still just as noisy.
I sold it, got a new (used) DCX, and the kit from http://www.linearaudio.nl/6chan-1.htm .
After some initial struggle, I got it running, and my analog x-over-project was posponed...
-now I have silence !!! (when wanted). Even without lowering the output-volume. The new front-end is that much better.
Arne K
BTW, I run the DCX with analog inputs...
I sold it, got a new (used) DCX, and the kit from http://www.linearaudio.nl/6chan-1.htm .
After some initial struggle, I got it running, and my analog x-over-project was posponed...
-now I have silence !!! (when wanted). Even without lowering the output-volume. The new front-end is that much better.
Arne K
BTW, I run the DCX with analog inputs...
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Good for you - dont know what output level Didden's mod actually provides - but from mere spec he is at -112 dB for THD & noise - whereas the stock unit is spec'ed at -112 dB for THD & noise - see what I mean ?
Have not measured, but don't think stock spec are way off...
So - what actually is the undistorted max output voltage of your modified unit ?
Michael
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Yes THD+N *is* usually measured at 1 kHz.
What I wanted to make clear - you do not know about output *signal* of your mod.
Again - look at the relation of THD+N with respect to signal - anything else is pretty worthless .
There are two possibilities - disconnect your input (or switch to digital-IN) turn fully up your volume and then tell us if there is lower noise as with stock unit.
If you have more or less the same noise - well...
If you have considerable lower noise - you have to check if you get the same signal strength as with stock unit....
If you have checked back that way - *then* and only then , you can tell how much the mod actually reduced noise of the unit - anything else are the benefits of voltage divider attenuation (or in case of the didden mod - VCO attenuation) - also known as the ominous "gain structure"
Michael
What I wanted to make clear - you do not know about output *signal* of your mod.
Again - look at the relation of THD+N with respect to signal - anything else is pretty worthless .
There are two possibilities - disconnect your input (or switch to digital-IN) turn fully up your volume and then tell us if there is lower noise as with stock unit.
If you have more or less the same noise - well...
If you have considerable lower noise - you have to check if you get the same signal strength as with stock unit....
If you have checked back that way - *then* and only then
, you can tell how much the mod actually reduced noise of the unit - anything else are the benefits of voltage divider attenuation (or in case of the didden mod - VCO attenuation) - also known as the ominous "gain structure" Michael
Yes THD+N *is* usually measured at 1 kHz.
What I wanted to make clear - you do not know about output *signal* of your mod.
Again - look at the relation of THD+N with respect to signal - anything else is pretty worthless .
There are two possibilities - disconnect your input (or switch to digital-IN) turn fully up your volume and then tell us if there is lower noise as with stock unit.
If you have more or less the same noise - well...
If you have considerable lower noise - you have to check if you get the same signal strength as with stock unit....
If you have checked back that way - *then* and only then
Michael
Not sure whether Jan's kit has the same 0dB out, but, regardless, it has a 6-channel attenuator after the DAC's, so, at anything but max volume, it will be attenuating background noise.
You both nail it – again - and again - and again - - - -
- S/N seems to be the most difficult lesson to learn in audio
Michael
Quick update. I got my DCX set up to drive my subs (AVR sub out > DCX > Class D amps with low impedance input). I set the preamp output on the AVR sub output at +10db and the DCX input gain at 0 db. I adjusted the balance between the subs and mains by turning down the output levels on the DCX (they ended up at -9 and -12 db for the two subs). Then I just used the receiver to control volume. Works fine. No noise at all when the Reciever volume is turned up loud (I did find there to be a bit of noise with pins 1 and 3 disconnected on the output XLR>RCA cables; this went away when I connected them). So the stock DCX seems to work fine for this application.
- Doug
- Doug
The perceived volume is the same, -analog settings are set at +3dB in, max(+6) at output,
All digital-settings are equal (maybe even increased the treble-shelf-lift slightly), -still use the same preamp(buffer), I use the same volume-range as before.
Difference is without "Linear-kit", I had a top-hiss I could hear more than 10m away on the Altec 909(or 299)/& MantaRays.
Now, I have to go closer than 1m just to hear the faint noise.
Arne K
All digital-settings are equal (maybe even increased the treble-shelf-lift slightly), -still use the same preamp(buffer), I use the same volume-range as before.
Difference is without "Linear-kit", I had a top-hiss I could hear more than 10m away on the Altec 909(or 299)/& MantaRays.
Now, I have to go closer than 1m just to hear the faint noise.
Arne K
you have cranked up your volume control of the modified DCX to full ?
Sanity check:
usually SPL falls -6dB each doubling of listening distance - so in your case from 1m to 10m its roughly 3 times -6dB = ~20dB
See ? - hard to believe....
Michael
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