Why does sound quality vary?

[Matt]

I was listing to the podcast about the Denon 1730 and they mention the sound was a lot better. Now if you are taking the digital signal from the DVD and sending it to a processor, surely its the amp thats doing the decoding. The digital signal from the player would be identical whatever the player.
How can this be?

[lunker]

I've always wondered this...

Also why do you need a decent digital audio connection between your DVD and Amp?

I thought digital was all or nothing?

[ninjafeel1970]

I found the same thing with my yamaha dvds1500 the sound from coaxial was not as good as a cheap philips dvd player, the chap i spoke to said sometimes its due to all the processing than goes on inside some dvd players. I dont know if there is any truth in this maybe some one else has other ideas

[Peter Galbavy]

A variety of DVD players have built in volume controls - this implies processing of the digital data, if the volume control has any effect on the output of the amp.

[trailer]

Originally Posted by Matt

I was listing to the podcast about the Denon 1730 and they mention the sound was a lot better. Now if you are taking the digital signal from the DVD and sending it to a processor, surely its the amp thats doing the decoding. The digital signal from the player would be identical whatever the player.
How can this be?

You have to get the data off the disc and out to the co-axial/optical socket.

Theres a lot involved in doing this.

[dor146]

Originally Posted by Matt

I was listing to the podcast about the Denon 1730 and they mention the sound was a lot better. Now if you are taking the digital signal from the DVD and sending it to a processor, surely its the amp thats doing the decoding. The digital signal from the player would be identical whatever the player.
How can this be?

I have wondered about this too. Like using a dvd player to play audio cds, the player reads the pcm of the disk and sends it out the back. It is the receiver that converts it to analog and i'll accept some do a better job at this than others.

[Matt]

Originally Posted by dor146

I have wondered about this too. Like using a dvd player to play audio cds, the player reads the pcm of the disk and sends it out the back. It is the receiver that converts it to analog and i'll accept some do a better job at this than others.

I accecpt that DACs can vary but i would have thought reading a digital signal from the disc and sending it to a decoder would be the same on every player, otherwise computers with different drivers wouldnt be able to read data discs.

[trailer]

Originally Posted by Matt

I accecpt that DACs can vary but i would have thought reading a digital signal from the disc and sending it to a decoder would be the same on every player, otherwise computers with different drivers wouldnt be able to read data discs.

A computer reading a data disc is surely different to running a DVD/CD. For instance a spreadsheet or word document is a "one time load". An audio CD or DVD is a continuous data process which needs to be synchronised to a clock and processed in a real time manner to the digital output.
Admittedly present day transports are far superior to earlier ones technically. The requirement for people to "Trichord clock" their transports now brings less of a benefit.

There is also the quality issue of the hardware involved. Cheap soldering and wiring, cheap connectors which don't fit snugly, poor power supplies, poor shielding etc etc can all make a difference!!!