[DanBa]

Thanks Kabeer !

I do some Google search.

“Compressed audio decoder with embedded USB host / controller: uPD63901
By just adding uPD63901 to the existing car audio system, iPod compatible system can be built easily.”
ESEC 2008 | Events Archive | Events | News & Event | NEC Electronics


“The AE1 (uPD63901) is the first SoC ever that integrates a USB 2.0-compatible (Full Speed at 12 Mbps) host controller, a digital signal processor (DSP) for decoding audio data recorded in MP3, WMA, and ACC formats, and a CPU for USB control.
Built-in components: USB host controller, MP3/MWA/AAC decoder, 1Mbit SRAM, 32KB SRAM for data retention, audio DAC”
AE1 | Car Audio System LSI | Automotive ASSP | Automotive | Products | NEC Electronics

“NEC AE1-30x iPod connectivity update
Audio (both 301 & 302)
• G1, G2 & G3 nano ? OK
• G5, G5.5 iPod ? OK
• iPod Classic ? OK
• iPod Touch ? OK
• Apple requires a new contract for iPhone.
− NEC Electronics will finalize contract with Apple by the end of December 2007 in order to obtain spec changes to the iAP protocol in order to support the iPhone.”
http://www.pcbfans.cn/upload/file/or...70d7771a92.pdf


The NEC chip is rather for low-end audio solution (car audio system …).
It is a USB host. It is able to access to the mass storage of a USB client device like USB memory stick or iPod.
It integrates some Apple authentication feature, an audio player, an audio DAC.

Some chip of the NEC AEx line can decode only MP3 / AAC files of the iPod storage.
It is not clear if the audio DAC of a NEC AEx chip can be bypassed: there is an audio digital output I2S according to the AE1 block diagram.

 

[Kabeer]

Quote:

Originally Posted by DanBa /img/forum/go_quote.gif Some chip of the NEC AEx line can decode only MP3 / AAC files of the iPod storage. It is not clear if the audio DAC of a NEC AEx chip can be bypassed: there is an audio digital output I2S according to the AE1 block diagram.

Thing is, Marantz claims that the digital audio signal is sent from this USB controller chip straight into the main Cirrus DAC processor. Which means an audiophile level DAC conversion.

The only person contesting it is that one reviewer. If he is correct, Marantz are lying in two of their CS replies, does this seem likely?

 

[insomniac_ut]

Hi Kabeer,

Did you ever get to the bottom of this? I'm interested in plugging my online library into my rig and am trying to juggle between the right pieces of equipment: a good CD player (the Marantz CD6003 comes to mind), a good DAC, the Onkyo NDS1 and a Squeezebox.

I'm leaning towards a DAC, the Onkyo dock and the Squeezebox. But if the 6003 is really perfoming the DAC conversion rather than taking a line input from the iPod, I'd be interested in this and will skip the DAC/dock altogether.

Thanks.

 

[Nak Man]

 
Quote:

These seem like excellent solutions for many Head-Fiers.
 

Well, it is, at least for me.
 
Glad to inform that my denon 710 gives digital output for ipod and even thumb usb.  It's now playing ipod thru optical with no rca connected. 
Almost pulled the trigger on onkyo 'transport' but thanks to this thread I got a real transport and the ability to play usb drives as a bonus ... neat.
 
UI itself is more than acceptable, I can browse by playslists, artists and also set shuffle /random mode from the remote.  So far older ipods don't work at all though.
 
cheers,
sm

 

[.Sup]

What iPod do you have NM?

 

[Nak Man]

I tried mini 2nd gen, 6gb model -> no go.
No sound coming off RCA even with ipod in play mode.
 
With a friend's classic 80gb (5th or 5.5th gen ?), UI works as promised. 
Best part for me is that it resumes last playback when powered off (from play or pause).
 
I can try with even older 40gb 4th gen, nano (not sure which gen, the shortie wide model) and touch 1st gen but I'd assume it will do what the manual said.
 
I was more interested on digital output part instead of UI, and quite surprised to see it can serve as digital dock ... since from the marantz review above mentioned that it doesn't allow digital out from usb.
  
Quote:

The uPD63901 does its own D/A conversion, so files read from the USB input completely bypass Marantz' CS4398-based digital section (and cannot be output via the Marantz digital outputs).

 
Would be a strange dumbed down method if Denon uses same chip.
There's a chance the reviewer didn't actually try it though ...

 

[.Sup]

I've been reading on Yamaha cd-s700 which also has usb input and it only does mp3 and acc though it but not wave. Have you tried playing wave files through the usb input?

 

[Nak Man]

Now that's strange.
 
Wavs inside ipod classic 80 played fine, however that same file when copied to USB thumb was not recognized.  Haven't tried apple lossless. 
 
Also noted similar behaviour to pinoeer HU which has USB input in that my 4gb usb was not recognized or caused the unit to 'hang'.  2gb is ok though.

 

[aspenx]

Any confirmation yet on whether it's really the CS4398 or the UPD63901 that does the work?
 
Quote:

Found it, the discussion was based on the CD8003 (which was the model the CD6003 was based on):
Questions about my Marantz SA8003 CD/SACD player [Archive] - SH Forums
Quote:

04-20-2009, 10:16 AM I just received a nice detailed response from Clarke Robinson, the reviewer from enjoythemusic.com: 2. The information about the USB input bypassing the unit's digital section I obtained by taking the unit apart and investigating the circuit myself. The UPD63901 is on a small board near the front panel of the unit (and it has a crystal oscillator on it, which it wouldn't need if it weren't doing D/A conversion). There is a single ribbon cable out of the USB board that leads directly to the unit's analog section. That's why you can't output USB to the digital outputs...the USB signal never touches the SA8003's digital circuitry. and then this from Marantz: Customer (James Hamilton) - 04/16/2009 10:09 AM when using an iPod with the SA8003 are the files decoded by the Cirrus CS4398 DAC or by the NEC uPD63901 microcontroller? Response (Ean Levy) - 04/20/2009 11:38 AM It is decoded by the Cirrus CS4398 DAC.