Behringer DCX2496 digital X-over

[MurphyUHF10]

Originally Posted by Davey

The modified DCX solutions (like Jan's) solve that problem and many others.

Based on your avatar, it appears you already have a Didden modified DCX? I'm not sure of the clipping behavior of the analog input portion of that unit.

Cheers,

Dave.

Yes I have the full Pilgham mods (apart from 4396's which i haven't installed yet).. And yes, having analog input adjust via the Didden mod is pricelsess,, so clipping on analog input is never an issue (only Digital)

Thanks Dave and Jan for explaining the issue of digital input clipping..
I must have poorly 'mixed' digital music then, because they all seem to have this 'max code' issue.. Any examples/sample of a 'good' digital mixing so I can better see for myself ??

Thanks
Murphy

[Pano]

For your calibration pleasure, here are 3 FLAC files to test your DCX input. (604KB)
All 3 tones are middle C sine wave. 44.1KHz, 16 bits, mono. 15 seconds each.

There is full scale, -1dB and -3dB. None of these are clipped, but the 0dBFS file is at the max it can go without clipping. If you set your DCX inputs to 0dBFS gain and have no EQ on the inputs, then the 0dB file is the hottest you'll get without clipping.

Certainly the -3dB file should show no red light. You can play around with the input gain to see where the red lights come on and off.

Any good CD burner should burn these to CD once you unzip them.

[Davey]

None of those three files will clip the outputs of the DCX.....IF you have no crossover or EQ programmed.
The red clipping indicators on the input channels will certainly illuminate with the 0dbFS file, but the output indicators should show amber and not red.

However, once you program a crossover the increased peak level of the outputs can slightly exceed the clipping threshold and flash the red indicators. (Even with no EQ programmed.)

Cheers,

Dave.

[AndrewT]

Thanks Pano.

Could you describe the method of creating these test signals and files?
A TEST CD with various R&L levels from -60dB to 0dB, single tones, twin tones, 20Hz to 20kHz would be a good tool.

[Pano]

Having a section of files for download is something the moderation team has briefly discussed. It would be very useful to our members.

I used a wave editing software called Goldwave that I've used for years. Very handy.
The procedure for those file was basically this:

• Open Goldwave and create a 15 second blank file. (mono, 16bit, 44.1 in this case)
• Open the "Expression Evaluator" in Goldwave.
• Choose the Sine preset from the menu
• Type in desired frequency (261.6255 for middle C)
• A full modulation sine is generated in the blank file.
• Double check by zooming in on waveform
• Save into desired format - e.g., wave, FLAC, MP3, AIFF, OGG, etc.
• Use "Maximize Volume" control to set peaks to desired level. -1, -3, -8.2, -32, whatever.
• Save each of these reduced volume files.

Sounds complicated, but it isn't. The Expression Evaluator can do all sorts of things, not just sine waves. It's a cool tool.

FLAC is a great format for this as it is lossless and yet these sine wave files go from about 1.2 Meg down to 256K. Quite a saving.

[MurphyUHF10]

Originally Posted by panomaniac

For your calibration pleasure, here are 3 FLAC files to test your DCX input. (604KB)
All 3 tones are middle C sine wave. 44.1KHz, 16 bits, mono. 15 seconds each.

There is full scale, -1dB and -3dB. None of these are clipped, but the 0dBFS file is at the max it can go without clipping. If you set your DCX inputs to 0dBFS gain and have no EQ on the inputs, then the 0dB file is the hottest you'll get without clipping.

Certainly the -3dB file should show no red light. You can play around with the input gain to see where the red lights come on and off.

Any good CD burner should burn these to CD once you unzip them.

Thanks Panomaniac..

I will download these files and report back with my findings!!

Cheers..

[AR2]

Happy New Year to all great people on this thread!

It has been a while that I have been playing with my DCX. I tried a lot with it. I think it is a good time to look at something else. So I did and wanted to share it with you. It is made by our member Thuneau. Check it out.
DSP Crossover for PC. Frequency Allocator.
I am sure some of you tried it already. I decided to purchase the full version since I do have a need for second active set up, plus it is great for playing with. My favorite feature is cappability to load .frd files of your speaker and place it as an overlay to your crossover. Than you work out EQ until you make it flat. Very cool! What is even more cool is that is made for ASIO drivers and my RME Fireface 800 sings with it perfectly.

Now what would be rally cool thing to do is to add outboard DA converters in order to have the ultimate system. That is nice that all these audio interfaces output analog and digital signals out, unlike DCX. Hmm, here is something for New Year.

[linsheng8]

How to join two DCX2496 divided into 4 stereo, (2 into 8) with a digital port input? Thank you

[AndrewT]

feed the same digital stereo signal to both DCX2496.

Then set up 4channels in each to drive a 4way or set up 6channels in one to drive two 3ways and 2channels in the other to drive two bass channels.

Depending on which drivers need more equalisation, the most resource hungry drivers should be fed from different DCX.

[linsheng8]

Each has only one digital input port DCX2496, DCX2496 can be configured for each to 4 mono-frequency, how allocated to the two DCX2496, thank you