Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Login


Options
View
Go to last post Go to first unread
fmak  
#1 Posted : Friday, April 4, 2008 4:56:15 AM(UTC)
fmak

Rank: Member

Groups: Member
Joined: 4/2/2008(UTC)
Posts: 15
Location: Cyprus

I was delighted with the module unitl I tried to get it to work at 176.4kHz which it should support.

Everthing else works including 88.2k and 192k even though I have had to reset.

Can Russ please help?

Fred Mak
Russ White  
#2 Posted : Friday, April 4, 2008 6:18:05 AM(UTC)
Russ White

Rank: Administration

Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN

Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
This is just the way the chip works in hardware mode. Read page 37 of the WM8804 datasheet.

If you want to be able to use 176.4khz you need to program a register via control interface (3 wire or 2 wire).

The WM8804 does not distinguish between 192 and 176.4khz in hardware more, so it will not correctly lock onto 176.4 unless you operate it in software mode. It expects anything > 96khz to be 192khz.

The current board does support software mode if you need to use 176.4khz. This would be an advanced configuration so you will need to do some research. I will help in any way I can.

Cheers!
Russ

Edited by user Friday, April 4, 2008 6:22:27 AM(UTC)  | Reason: Not specified

fmak  
#3 Posted : Friday, April 4, 2008 10:35:38 AM(UTC)
fmak

Rank: Member

Groups: Member
Joined: 4/2/2008(UTC)
Posts: 15
Location: Cyprus

Russ White wrote:
This is just the way the chip works in hardware mode. Read page 37 of the WM8804 datasheet.

The WM8804 does not distinguish between 192 and 176.4khz in hardware more, so it will not correctly lock onto 176.4 unless you operate it in software mode. It expects anything > 96khz to be 192khz.

The current board does support software mode if you need to use 176.4khz. This would be an advanced configuration so you will need to do some research. I will help in any way I can.

Cheers!
Russ


Sad that WM should have chosen to do this. Implementing 176.4k in Mode 1 doesn't seem easy and there is a question of auto switching back to Modes 2,3,4.

Are you likely to implement this on a new board as the WM seems (and sounds) good as a dejitter tool? And there are few good ones that support high sampling rates. To assume that asrc from 44.1 to 196 or 192k is the right choice is just plain wrong - integer upsampling on my dCS sounds much better. 192k from 44.1 can sound impressive but loses the naturalness of 176.4.

Fred
Hercules  
#4 Posted : Friday, September 16, 2011 5:14:27 AM(UTC)
Hercules

Rank: Advanced Member

Groups: Member
Joined: 4/16/2009(UTC)
Posts: 56
Location: Hong Kong

Hi Russ:

Just received WM8804 from Brian, so I finished my Opus 2.1, works with 44, 88, 96 and 192K but not 176.4, any solution now? Opus in software mode, Volumite with Opus Stereo Firmware, PB1 and PB3 to GND.
Russ White  
#5 Posted : Friday, September 16, 2011 5:40:19 AM(UTC)
Russ White

Rank: Administration

Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN

Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
This is a well known issue with the WM8804 in hardware mode. See the datasheet for more info. It is simply the way that the receiver is designed.

Edited by user Friday, September 16, 2011 6:04:32 PM(UTC)  | Reason: Not specified

Rss Feed  Atom Feed
Users browsing this topic
GuestUser (2)
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.