DSP Xover project (part 2)

Wow, looks great JC!

Yes, that looks very nice indeed.

Thanks,
I listened to it quite extensively on my headphones (Senheiser HD580 / Westone 4) as a pass through 96 kHz (USB amanero input / sym output to a RME Fireface 400) and... I like the transparency. Next step will be on my three ways active system but for this I need a little more free time to make measurements and calculate adequate filters ! Hopefully later this month

JC
 
Chris,
Nothing fancy here I followed the design sheet.

as I' decided not to touch the Najda board itself, I've just added input- output boards to the existing circuits. So yes, it is connected to the back of the RCA connectors because of its reversibility.

Due to the box I selected I had size constraint so 50 mm max for the 2 inputs board and 100 mm for each of the 4 output boards. (25 mm between each XLR)

I selected That Corporation IC 1200 serie for the input and 1646 for outputs for their good performances.

I added also RFI protection on inputs so I had to use CMS for that specific small board. Output board uses "normal" components.

To increase the input margin from 1V RMS to 2 VRMS, I selected 1206 chips (-6dB) but of course 1200 model (0 dB) could be soldered too.

here are the top and bottom of input board

Hope this helps

For the input board,
 

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New feature request:

I would like to be able to choose which channels are enabled for a particular setup. At the moment, all channels are always set to feed through a signal. But I would like to switch off specific channels. Specifically, I want to configure Najda to be a 2x3-way crossover in one setup (, 3, 5, 6, 7) and a feed-through DAC (using channels 4, 8) in another. Whichever preset I select, I want the other outputs to be muted.
 
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Hi Shaun,

I'll look at enabling and disabling channels in the context of processing optimisation for those who use 192 kHz sampling rate in particular.

In the meantime, you can achieve your goal with custom biquads: for those channels that you want disabled, simply load one custom biquad with all coefs 0.

If you switch to FIR at some point, you can also get the same result by loading for each of the disabled channels an empty coef file (which is the default when creating a new setup).

Best,

Nick
 
@ JLOP:

I use Najda for my main loudspeakers (active, of course), but I also build passive loudspeakers, and then I sometimes like to listen to my second pair of speakers, Yamaha NS-1000s (also passive - for now :devily:).

If you are comparing passive vs active versions of the same speaker configuration, I guess you should do it with a single speaker active and the other passive. Keeping the passive filter connected while trying to listen active is not workable, IMO.