As Far as I know, the PCM2707 is stereo(2 channel)
DO you want to stream the encoded 5.1 data from your PC? I am not sure you will be able to do that via USB, i think that that has not been developed as of yet, but I am not sure. You can stream it encoded via SPDIF to a 5.1 decoder, i am sure there are many available chips out there to decode 5.1..
This is just a hobby of mine, I am not an expert at this, but i have done loads of reading and research in the net..
If you have not yet, Check the AVS forum. They have a Home theater Computer section.. They know some stuff and do have many 'Experts' on the forum.
will this help you guys:
The WM8522 is a multi-channel audio DAC ideal for DVD and surround sound processing applications for home hi-fi, automotive and other audio visual equipment.
Three stereo 24-bit multi-bit sigma delta DACs are used with oversampling digital interpolation filters. Digital audio input word lengths from 16-32 bits and sampling rates from 8kHz to 192kHz are supported.
Each DAC channel has independent digital volume and mute control, and provides 1.7Vrms line drive capability from a 5V supply. This makes the device ideal for cost-sensitive consumer applications requiring high line drive audio outputs.
The audio data interface supports I2S, left justified, right justified and DSP digital audio formats.
The device is controlled via a 3 wire serial interface or directly using the hardware interface. These interfaces provide access to features including channel selection, volume controls, mutes, de-emphasis and power management facilities. The device is available in a 28-lead SSOP.edit: crap...it's 6 chan, you want 8
* 6-Channel DAC with 1.7Vrms line driver from 5V analogue supply
* Audio performance
* - SNR 102dB (‘A’ weighted @ 48kHz)
* - THD -85dB (48kHz)
* DAC sampling frequency: 8kHz – 192kHz
* 3-Wire SPI serial or hardware control interface
* Programmable audio data interface modes
* - I2S, left, right justified or DSP
* - 16/20/24/32 bit word lengths
* Three independent stereo DAC outputs with independent digital volume controls
* Master or slave audio data interface
* 4.5V to 5.5V analogue, 2.7V to 3.6V digital supply operation
* Pin compatible with WM8766
* 28-lead SSOP package
edit (again): AH-HA!! They have an 8 chan version too!
The WM8768 is a multi-channel audio DAC ideal for DVD and surround sound processing applications for home hi-fi, automotive and other audio visual equipment.
Four stereo 24-bit multi-bit sigma delta DACs are used with oversampling digital interpolation filters. Digital audio input word lengths from 16-32 bits and sampling rates from 8kHz to 192kHz are supported. Each DAC channel has independent digital volume and mute control.
The audio data interface supports I2S, left justified, right justified and DSP digital audio formats.The device is controlled either via a 3 wire serial interface or directly using the hardware interface. These interfaces provide access to features including channel selection, volume controls, mutes, de-emphasis and power management facilities. The device is available in a 28-pin SSOP.
8-Channel DAC with PCM
103dB SNR (‘A’ weighted @ 48kHz) DAC
DAC Sampling Frequency: 8kHz – 192kHz
3-Wire SPI Serial or Hardware Control Interface
Programmable Audio Data Interface Modes
I2S, Left, Right Justified or DSP
16/20/24/32 bit Word Lengths
Four independent stereo DAC outputs with independent digital volume controls
Master or Slave Audio Data Interface
2.7V to 5.5V Analogue, 2.7V to 3.6V Digital Supply Operation
28 pin SSOP Package
Even better (Sorry had to trump you) : AK4358
Now if only we could find a chip to communicate to that via USB...1. Sampling Rate Ranging from 8kHz to 192kHz
2. 24Bit 8 times Digital Filter with Slow roll-off option
3. THD+N: -94dB
4. DR, S/N: 112dB
5. High Tolerance to Clock Jitter
6. Low Distortion Differential Output
7. DSD Data input available
8. Digital De-emphasis for 32, 44.1 & 48kHz sampling
9. Zero Detect function
10. Channel Independent Digital Attenuator with soft-transition (3 Speed mode)
11. Soft Mute
12. 3-wire Serial and I2C Bus µP I/F for mode setting
13. I/F format: MSB justified, LSB justified (16bit, 20bit, 24bit), I2S, TDM or DSD
14. Master clock: 256fs, 384fs, 512fs or 768fs (PCM Normal Speed Mode)
128fs, 192fs, 256fs or 384fs (PCM Double Speed Mode)
128fs or 192fs (PCM Quad Speed Mode)
512fs or 768fs (DSD Mode)
15. Power Supply: 4.75 to 5.25V
16. 48pin LQFP Package
17. Evaluation Board: AKD4358
I saw those as well (see post #160 and #180) and they would work for the DAC/CODEC processing part. What I am looking specificly for is an USB to I2S chip that is more than 2 channels, but more like 5.1 or even 7.1. This is proving hard to find. I have started to read about I2S to see if there are limitations and therefore no 5.1 on the I2S bus.
I looked at some Realtek's and other makers' soundchips, but they tap PCM outputs from the MB. So they won't work either, unless I find a USB to 7.1 PCM chip.
Thanks for also looking!
Oops missed that post Roaddog, Felix also posted about the wolfson one.
So here are our contenders for the DAC section, we still need the USB to DAC communication chip
1) TI Burr Brown PCM4104 (4 channel DAC)x2
2) AK4358 (8 channel)
3) Wolfson WM8768 (8channel DAC)
If two 4 channels can be strung together on the EVAL board like Felix said, then we should be able to string 4-5, 2 channel higher quality DACS.
oh sorry man, this thread moves so fast and I just stumbled apon those while looking for a solution for turbocad's install and thought i'd post it.
how about this:
i believe this is who made the eval board for my dac...sorry again if it was posted earlier
here is a link ot more on the site:
I may not write clearly, so it could have been my fault. Red made that apparent to me.
I really would like to find a USB audio to 7.1 <something> chip for the front end instead of trying to write a media player that has to split the channels out to send it down the USB bus to 4 or so seperate converters to put it back together for the listener. I would think this is a nightmare and a band-aid.
I have seen tons of USB to 4 1/8 inch jacks (or properitary like Turtle Beach's Roadie) for 7.1. I wondering if I should get my hands on one of them and tear it apart? Maybe it is not a bad idea. Be back!
No doubt the thread moves right along..
The PCM4104 eval board::
It has (2) of the 4 channel chips on the same board.. It has I2S inputs among other(AES/EBU, S/PDIF)
From looking around, it seems there are quite a few of the digital receiver chips to get from USB to I2S. Most are 16 bit/ 48KHZ max, but i am not sure that is a problem.
Here are a few USB to I2S chips
BB PCM 2707, 2706
TI TAS1020, TUSB3200 (need to write drivers)
The M-Audio Transit uses the TAS1020 and will do higher resolution, it will do 24/96.
The Edirol UA-1EX uses the TUSB3200 chip and also does 24/96.
I2S is designed to go between chips, so it will only travel a few inches.
There ya Go, ENjoy!