DSP Xover project (part 2)

I did think Octo is a DAC. Does it do DSP also or is there a special configuration?

Maybe it has a Raspberry inside. If so then is the question of how many tapps can it do FIR.

On Octoresearch homepages are stated that the lead time is long. But nothing that it would not be delivered if ordered.
"Our current lead time is 6-8 weeks. Please contact us if you have an EU VAT number and want to make a purchase with VAT excluded."

They briefly released a DSP version that used the Nano SHARC DSP. I think they do about 4096 TAPS @ 96kHz.HOWEVER, the cool thing about this unit is you can mix both IIR and FIR filters. The frustrating thing about NAJDA was it was one or the other.
 
thanks, but didnt really tell me anything I didnt know :) I was hoping for some news on AKM. I literally had AK4499 in my cart when the fire happened and it is because of companies like danville taking precedence that those parts suddenly became unavailable a the distributors and I had to redesign my dacs that I was working on, to use ESS parts. Not happy Jan!! Cheers for the link though mate.
 
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Anybody know if it is possible to download the internal memories from the najda?
I burned the hd with all the memories! ��
I've searched for a method, but nothing coming up.
I've never done it or seen options in the Najda in Control menu to allow it.
Always have to load the file (usually latest in my case), and connect and to store a changed or live changed one back as a preset.

It would have been a good feature of files lost.

Not much help now but I always store them in the cloud with local copy just for backup.
 
Does anyone has unused analog expansion board laying around and wanting to sell it?

I need one additional analog output channel with volume control
Hehe, join the orderly queue behind me[emoji3]

I think they are like hens teeth.
I gave up asking around 2014 or so. Got used to my passive tweeter cross in and in that time, they had been produced, sold and all gone!
Boat missed.
 
Today I sent the split output (no upper X/O) that goes to my upper mid and tweeter channels, so that it goes to the upper mid channel and off to a second Najda and into its analogue input.
There the 2nd Najda performs X/O for tweeters and out to the tweeter amp.

I have been able to quickly evaluate
2nd order, 3rd order and 4th order LR and BS X/Os at a range of frequencies.
9000, 10000, 11000 and 12000.

As far as my ears can tell the 2nd Najda is transparent and works very well, set on 0dB there is no volume difference.

I'm still evaluating but it's a toss up between 3rd order BS or 4th order LR.

Thought I'd mention it for general interest.
 
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Hey!

Pointing out some dumb questions, after using Najda solely digital over the last years, I have now managed to fix my turntable and would like to run that through the chain as well. It is Transcriptor Hydraulic Reference that I got for little money and had to fix up, I am using a Musical Fidelity V90 LPS as a pre-amp, but I am getting AD clipping every now and then and I can't adjust the pre-amp volume.

Do I just up the dip switch on the input jack to 2Vrms?

I am by no means an electrical engineer, I rather ask before doing something that I don't even know about what it does.

Same for the output, I am using PAS Audio 2002PCA amplifiers that work just fine, but never go from showing "ready" (orange) to "signal" (green), I assume the output level from the Najda is just too low for the power amplifier., from the manual I can read this might be adjustable as well, but can't remember my board layout on that end. The manual from PAS Audio states Input Sensitivity for full Power(260W/4Ohm) 1,07V, which makes me wonder what the problem is.

Any small hints appreciated!
Cheers, Alex
 
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Hello, you will find the appropriate tools in NUC (thé Najda software) that will let you adjust thé input level (I run it at-3db to avoir clipping) and voltage output. Yours must be set at 1V but you can go up to 6V.
Off course you need to install NUC and connect with a proper Usb cable !
 
Hi,

Cheers for the reply. I am running a simple pass-through routing, the clipping is already at the AD conversion step and I don't think lowering gain at the input stage thereafter will sort the problem, but happy to test. It might be that I have completely misunderstood the block diagram.

If anyone could explain what the difference is of 1V and 2V RMS nominal input level, that would be superb!

Cheers, Alex