As the Beatles once wrote, in a song, ‘Help, I need somebody’. In this case, somebody particularly familiar with the Behringer DCX2496 and its foibles.
Here’s my weird situation with my Behringer set up, and it’s driving me crazy. I apologize for the wordy post but I thought it best to explain as best I can.
First, the setup: Tunes are typically FLAC, ripped from CDs and saved to a Mac Mini. It’s then USB out to an S.M.S.L. device which takes the USB and converts it to SP/DIF through coaxial. That feeds into a Behringer SRC2496. The SRC feeds into a DEQ2496 via an AES/EBU cable, and then, also with an AES/EBU cable, to a DCX2496. The DCX2496 then feeds two PP tube amps which connect to a pair of Beyma 12KX coaxials.
The problem: Some tunes sound fine, though I’m so gun shy at this point, I’m not sure, but at least they don’t have the same issue. The weird thing? On some songs, the vocals disappear. Example: The Beatles Eleanor Rigby where the chorus is fine but after a couple words of the verse, the vocals recede dramatically, but come back for the chorus. Jimi Hendrix’s ‘Are You Experienced’ album where the first track sounds alright, but on the second the vocals are gone. Not faint, gone. Third track, normal. The Stones ‘Gimmee Shelter’: Mic I can barely hear you. I don’t just listen to old ‘stuff’, and it generally seems newer recordings don’t do this - or perhaps I just haven’t found one yet. Diana Krall seems fine, Adele, too. Black Pumas, all good.
What I’ve done: I’ve tried LR2, and LR4, on the DCX with no effect (xover at 1.19 or 1.21 Khz). I’ve checked, with a meter, the polarity on all the cables. I’ve tested the woofers with batteries to ensure they move out with the + to the positive post (just in case I miswired internally). I’ve tried different apps on the Mac, with the same results. I’ve aligned the drivers (receding the woofer by 28mm according to the DCX, and checked polarity.) I’ve measured the 12KX with REW and with the DEQ clean (no house curve, no eq) have set up PEQs on the DCX hoping that would linearize the drivers before being crossed. (I don’t know if the DCX does it in that order, ‘cause the manual wouldn’t tell one that). Anyway, the problem was still there..
I brought over my pair of Dynaco A25s shop speakers and hooked up each amp, in turn, from the DEQ’s outputs to test the chain other than the DCX, and those problematic songs were normal.
I have a rough set of small test boxes with a PRV 5MR450-NDY in each. I’ve put them on the 12KX cabinets and crossed them at 303 hz with the 12KX woofer, using an LR2, so they’re functioning as a WAW or FAST (depending on the flavour of the week). The 5MR450 is delayed by 68 mm, according to the DCX. The result … still weird.
My summation is that the problem is not in the 12KX speakers themselves, or the chain from the Mac Mini through to the DEQ. That seems to leave the DCX as being the issue.
What setting, or settings, on the DCX would be causing this? I’m using digital input A, the configuration is LF-HF-LF-HF-LF-HF, with outputs 5 & 6 muted. I’m not using (or don’t think I am) anything other than PEQ (and that really only as noted above as I just want it to work before I get fiddely).
Does anyone have any insight? Any suggestions? Any relevant questions? (Don’t need ‘why didn’t I buy a MiniDSP instead’ ….) My alternative is to build a passive crossover for the 12KX - I’ve measured them and have used Xsim to design something. However, if I don’t need to drop several hundred for crossover parts, I’d rather not. And, besides, this is just really annoying and I’d like to find an answer.
Here’s my weird situation with my Behringer set up, and it’s driving me crazy. I apologize for the wordy post but I thought it best to explain as best I can.
First, the setup: Tunes are typically FLAC, ripped from CDs and saved to a Mac Mini. It’s then USB out to an S.M.S.L. device which takes the USB and converts it to SP/DIF through coaxial. That feeds into a Behringer SRC2496. The SRC feeds into a DEQ2496 via an AES/EBU cable, and then, also with an AES/EBU cable, to a DCX2496. The DCX2496 then feeds two PP tube amps which connect to a pair of Beyma 12KX coaxials.
The problem: Some tunes sound fine, though I’m so gun shy at this point, I’m not sure, but at least they don’t have the same issue. The weird thing? On some songs, the vocals disappear. Example: The Beatles Eleanor Rigby where the chorus is fine but after a couple words of the verse, the vocals recede dramatically, but come back for the chorus. Jimi Hendrix’s ‘Are You Experienced’ album where the first track sounds alright, but on the second the vocals are gone. Not faint, gone. Third track, normal. The Stones ‘Gimmee Shelter’: Mic I can barely hear you. I don’t just listen to old ‘stuff’, and it generally seems newer recordings don’t do this - or perhaps I just haven’t found one yet. Diana Krall seems fine, Adele, too. Black Pumas, all good.
What I’ve done: I’ve tried LR2, and LR4, on the DCX with no effect (xover at 1.19 or 1.21 Khz). I’ve checked, with a meter, the polarity on all the cables. I’ve tested the woofers with batteries to ensure they move out with the + to the positive post (just in case I miswired internally). I’ve tried different apps on the Mac, with the same results. I’ve aligned the drivers (receding the woofer by 28mm according to the DCX, and checked polarity.) I’ve measured the 12KX with REW and with the DEQ clean (no house curve, no eq) have set up PEQs on the DCX hoping that would linearize the drivers before being crossed. (I don’t know if the DCX does it in that order, ‘cause the manual wouldn’t tell one that). Anyway, the problem was still there..
I brought over my pair of Dynaco A25s shop speakers and hooked up each amp, in turn, from the DEQ’s outputs to test the chain other than the DCX, and those problematic songs were normal.
I have a rough set of small test boxes with a PRV 5MR450-NDY in each. I’ve put them on the 12KX cabinets and crossed them at 303 hz with the 12KX woofer, using an LR2, so they’re functioning as a WAW or FAST (depending on the flavour of the week). The 5MR450 is delayed by 68 mm, according to the DCX. The result … still weird.
My summation is that the problem is not in the 12KX speakers themselves, or the chain from the Mac Mini through to the DEQ. That seems to leave the DCX as being the issue.
What setting, or settings, on the DCX would be causing this? I’m using digital input A, the configuration is LF-HF-LF-HF-LF-HF, with outputs 5 & 6 muted. I’m not using (or don’t think I am) anything other than PEQ (and that really only as noted above as I just want it to work before I get fiddely).
Does anyone have any insight? Any suggestions? Any relevant questions? (Don’t need ‘why didn’t I buy a MiniDSP instead’ ….) My alternative is to build a passive crossover for the 12KX - I’ve measured them and have used Xsim to design something. However, if I don’t need to drop several hundred for crossover parts, I’d rather not. And, besides, this is just really annoying and I’d like to find an answer.
HI
I have used the DCX for many years and I don't know what your problem could be. It never failed me.
But I do remember any problems with the SRC. You can eliminate it without problems from your setup. Both the DEQ and DCX work directly with spdif signal. You just have to get cable.
Also try to do without the DEQ. With the DCX you should have plenty of EQ options.
I have used the DCX for many years and I don't know what your problem could be. It never failed me.
But I do remember any problems with the SRC. You can eliminate it without problems from your setup. Both the DEQ and DCX work directly with spdif signal. You just have to get cable.
Also try to do without the DEQ. With the DCX you should have plenty of EQ options.
I agree the SRC is rather redundant. Unfortunately, given what I'm experiencing removing either, or both, the SRC and DEQ still won't solve my problem. 😰
What routing do you have setup in the DCX?
Anything summed in the DCX or the DEQ? Should not be.
Also check that there is no polarity reversal set anywhere in the processing.
How are the amps configured, can they be set to bridged mode? They should be set to stereo or dual channel mode.
What you describe sounds like a summing cancellation, something similar can occur if an unbalanced stereo signal is fed to a balanced mono input, everything common on the two channels.. usually vocals without any effects, gets cancelled.
Anything summed in the DCX or the DEQ? Should not be.
Also check that there is no polarity reversal set anywhere in the processing.
How are the amps configured, can they be set to bridged mode? They should be set to stereo or dual channel mode.
What you describe sounds like a summing cancellation, something similar can occur if an unbalanced stereo signal is fed to a balanced mono input, everything common on the two channels.. usually vocals without any effects, gets cancelled.
Hmm, I'll check the routing and whether anything is summed. No polarity reversal, other than if, after using a mic and DCX, it wants a reversal. I have checked all the balanced to unbalanced cables to ensure they're correct. Ah, tube amps, so no bridging, just stereo.
Thanks for the tip on routing, that's today's project once I move snow after our big wind event.
Thanks for the tip on routing, that's today's project once I move snow after our big wind event.
I checked several things:
Routing:
In A - to #1 #2 #3 #4 (5 & 6 unconnected).
In B - blank
In C - to #5 & #6
'Sum' no connection
Setup In/Out:
Out - LH LH LH
Out - 'Link On'
In - Stereo Line A + B
In - A + B Source AES/EBU (which is A)
Sum (Button):
In select: 'Off'
In (Button):
In A - connects to #1 #2 #3 #4
'Sum' no connection
And .... still does the same weird thing. WTH am I missing?
Routing:
In A - to #1 #2 #3 #4 (5 & 6 unconnected).
In B - blank
In C - to #5 & #6
'Sum' no connection
Setup In/Out:
Out - LH LH LH
Out - 'Link On'
In - Stereo Line A + B
In - A + B Source AES/EBU (which is A)
Sum (Button):
In select: 'Off'
In (Button):
In A - connects to #1 #2 #3 #4
'Sum' no connection
And .... still does the same weird thing. WTH am I missing?
So you have a single XLR cable between the SRC and the DCX supplying the digital link?
Have you tried simply using the analog outputs of the SRC to feed the DCX.. even as a test? If that works fine then there is something going on with the way you have the DCX configured for a digital input. If that doesn't change anything then the problem is elsewhere
I have 2 DCX I use for PA stuff but have never tried to put a digital signal into them.
Have you tried simply using the analog outputs of the SRC to feed the DCX.. even as a test? If that works fine then there is something going on with the way you have the DCX configured for a digital input. If that doesn't change anything then the problem is elsewhere
I have 2 DCX I use for PA stuff but have never tried to put a digital signal into them.
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Yes, an XLR from the SRC to the DEQ and another from the DEQ to the DCX. I have never used the analog ins or outs, but it's a good test. I have optical cables, too, so will try bypassing the SRC - not really needed - and see what happens.
I use the dcx for speaker setup to one of my small 3 way PA system feed with aes digital all the time for years and it sounds perfect the only problem is for one time the frying eggs sound and solvent with remove and set back and glued the ribbon cable.Note your crossover curves type and frequency numbers on paper or take few photos with your phone and do factory reset the unit.Maybe is something wrong set and you get this problem.
If I remember right when I used a DEQ->a pair of DCX for a stereo 4-way left is A and right is B. I think you are running one channel. I think you want 1 connected to A, 2 connected to B, 3 connected to A and 4 connected to B. Its been awhile though, I switched to a different system.
WAIT
That firmware will brick older units, I believe that release is only compatible with the latest LE models.
I don't think this will solve your issue but I did note that my DCX/DEQ needed an async DAC to work properly, also a 110ohm AES cable
Take a lok at the block diagram for the DCX, once a digital input is recieved (on input A) it automatically routes L and R signals to the A & B busses.
What MikeATX is saying is it looks like you have all your DCX outputs tied to the A bus in the routing which is the L channel only in a stereo feed, you need some of those tied to the B bus for the right channel.
What MikeATX is saying is it looks like you have all your DCX outputs tied to the A bus in the routing which is the L channel only in a stereo feed, you need some of those tied to the B bus for the right channel.
Hmm ... thanks. I'll take a look.
This is with the Setup button
Setup -> In/Out
In Stereo Link A + B
In A + B Source: AES/EBU
I can't see a) how this isn't providing a digital signal to both A + B. Also under 'A' button (left most button) there are no routing options.
This is with the Setup button
Setup -> In/Out
In Stereo Link A + B
In A + B Source: AES/EBU
I can't see a) how this isn't providing a digital signal to both A + B. Also under 'A' button (left most button) there are no routing options.
Do you want some test signals? I can make up a few and post them.
I have owned and modified several DCX over the years and driven them with digital signals from a laptop[ or from a DEQ. You should not be having this problem.
I have owned and modified several DCX over the years and driven them with digital signals from a laptop[ or from a DEQ. You should not be having this problem.
Anything that would help, Pano. 🙂
From looking at the block diagram (back of the manual) input A, when digital, provide signal to both A and B.
Also, a quick check shows I already have 1.18A, so no fear of bricking with a firmware update.
From looking at the block diagram (back of the manual) input A, when digital, provide signal to both A and B.
Also, a quick check shows I already have 1.18A, so no fear of bricking with a firmware update.
Okay, I'm officially an idiot - several times over. (Should have posted my issue on here a long time ago ....) My outputs #2 and #4 (left channel LF and HF) were on A. A quick switch to B and voila ...
You guys were right, so big thanks to Conanski and MikeATX. I was stuck on A as an input and never thought of another channel ....
You guys were right, so big thanks to Conanski and MikeATX. I was stuck on A as an input and never thought of another channel ....