Home
AudioAsylum Trader
Digital Drive

Upsamplers, DACs, jitter, shakes and analogue withdrawals, this is it.

For Sale Ads

FAQ / News / Events

 

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.

You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login


Login to access features only available to registered Asylum Inmates.
    By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username:

The Name that you picked or by default, your email.
Forgot Moniker?

 
 

Examples "Rapper", "Bob W", "joe@aol.com".

Password:    

Forgot Password?

 Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:  
Your Email:  
Subject:  

Message Comments

   

Original Message

bit perfect DSD

Posted by Tony Lauck on February 29, 2012 at 11:34:17:

"I'm not at all clear on what it means to have (or not have) bit-perfect SACD. I certainly understand "bit perfect" -- just not in an SACD context."

I should think that bit perfect SACD would mean that the DSD bits on the disk are transferred to the DAC unchanged. Specifically, the bits going to the DAC would correspond to the DSD master file produced during the mastering process. (The actual pits on the disk would be the result of losslessly compressing the bit stream, encrypting with a DRM key, and then encoding with the optical disk format coding. All of these operations, undone correctly, should produce the original bit stream.)

What the DAC does with these bits are something else. If the bit stream is sent to a flip flop and this is clocked and low pass filtered then the DAC itself is a pure DSD implementation. If the DAC upsamples the DSD to even higher sampling rates then I would say this is still a pure DSD implementation. (Example, the ESS SABRE chips.) However, if the DAC downsamples to a lower sample rate then this would not constitute pure DSD, wherever done. Among other reasons, transients would be smeared due to the necessary filtering.

There is no fundamental difference between PCM and DSD once one considers the application of dither and noise shaping in the PCM environment, as is common today. DSD64 is nothing but noise shaped PCM with a sample rate of 2,822,400 Hz and a word length of 1 bit.