8 channel LPCM over HDMI, It's Multi Amp for Everyone

[phofman]

Hi KOON3876,

I am by no means trying to tell you what you should do. I just wanted to bring up the question of making a library with documented (probably very simple) API and perhaps your existing example use. The library would allow other people easily incorporate the functionality into other projects, send back patches, etc. Something like the CUDA image manipulation library http://cvtool.sourceforge.net/.

BTW, what is the license of your code?

Thanks.

[KOON3876]

library or separated source?
int CUDAFIR_Initialize(int taps, int channels)
int CUDAFIR_Close()
int CUDAFIR_PrepareCoeff(int channel, EQ * pEQParams, FREQ * pFreqParams)
int CUDAFIR_DelayAndOffset(int channel, int delay, float offset)
int CUDAFIR_Execute(int channel, float * indata, float *outdata, int length)

looks nice, it can organize source
but there are bad effect, users will not study CUDA. will think later.

License, MIT?
I avoid download / look "GPL" source codes, so there will be no problem to say it's MIT licensed.
Same as PortAudio license.

[KOON3876]

I uploaded GPUFIR_20080901.zip,
Now there are 4 components.
(1) Tiny player / controller.
(2) FIR Output process, with File read / buffer function.
(3) ShareDLL, command / responce communication and 256KB FIFO.
(4) Input Streamer.

Most interesting thing will be codes are so small.
(1) VB2005 220 lines
(2) VC2005, 850 lines
(3) VC2005, 120 lines + data segment
(4) VC2005, 180 lines
Total below 1500 lines.

(1) is simple player written from scratch.
(2) GPUFIR output program, has it's own Linear buffer for file.
This player reads all of data into RAM first, then start playing.
Pros: there are no hardware access to disks while playing.
Cons: Slow when NAS connected by Wifi. I'm not sure I can play 2GB wave file .
(3) is DLL which connects C and VB, also it stores fixed 256KB FIFO for (2)-(4) communication.
(4) is "Input Only" PortAudio program.

Screen: GPU FIR / Input Streamer / Controller.
I just drag / drop folder or file, then play / pause / stop / FWD / REW. so simple!
or by checking "Streamer Mode", I can listen to CD player.
So far (3 hours) no problem about CD/HDMI async issue. When FIFO goes almost FULL/EMPTY, program remove or insert one packet.


OK now I can go to next, where I want to go
6 way LAN I2S device (netburner+cheap FPGA) - full digital amplifier.

[soundcheck]

Originally posted by KOON3876

OK now I can go to next, where I want to go
6 way LAN I2S device (netburner+cheap FPGA) - full digital amplifier.

Good to see that you start with the 6 way ethernet device.
Perhaps you should start up a new thread for that.

Cheers

[adelias]

Originally posted by KOON3876


That sounds interesting, We don't need Lynx anymore?
If Mod Xonar can output 8 channel I2S, Or 6 channel I2S is on the main-daughter cable, any DAC DIYer can enjoy.

Not PortAudio->CUDA->Xonar
some APP -> PortAudio -> Xonar

Using PortAudio is very easy and platform (almost) free,
I recommend any Sunday DIYAudio programmer to learn PortAudio.

So has anyone got a Xonar HDAV1.3 yet and can verify that it passes I2S on to its daughterboard?

[soundcheck]

It has to be 3*2*I2S, since the DACs are sitting on the daughterboard.

1. I am wondering at what frequency ( X*fs?) they are running
2. I was also wondering if the card is able to handle native 44.1/16

It seems that the card is also - partially - running under Linux (Alsa 1.0.18)

[phofman]

I do not have the card, just inferring from ALSA source code and datasheets.

CMI8788 supports 192/24 I2S, so do PCM1796 codecs, Asus specifies 192/24 too.

CMI8788 supports 44.1kHz (OXYGEN_RATE_44100 in alsa). However, it has only one 24,576 MHz crystal, i.e. the 44.1kHz support is provided via PLL, no direct clock.

Unfortunately I do not know any PCI-express card with direct clock pro 44.1kHz.

[soundcheck]

In general the card looks promising to me.

Especially from a DIY tweaking perspective.

There is no other card offering so easy access to a multichannel I2S bus.
Feeding Koon's full-digi-amps with the I2S signal might be a very nice way forward.
That's what I am looking for, for quite some time.

Koon: Are you listening?

[KOON3876]

Hi is this the one we want?

http://www.newegg.com/Product/Produc...82E16829132008

Package photo shows it has daughter card.

I was pretty busy to keep my assets in financial storm and business. From last week I started thinking how to implement LAN I2S to NetBurner.

I will consider Xonar later! (my pocket money is pretty poor now... I bought Dell 3008 / 64GB SLC SSD / 128GB MLC SSD this month)

[soundcheck]

Yep.

That's the one. The Deluxe package comes with a daughter-board.

It also delivers quite some nice features for multimedia/blue-ray/HDMI-audio asf.
But I doubt that Linux is supporting the fancy stuff. We (The Linux community) will never get rid of a dual-boot machines. That's for sure.