Chambers wrote:
> Warp wrote:
>>   I clearly remember how they advertised digital TV as increasing the
>> image quality compared to analog broadcasts. BS.
> 
> One of my hobbies is explaining to people how it is actually impossible 
> for a digital system to rival the quality of an analog.
> 

Define impossible. ;)

The relevant concept here is the signal to disturbance ratio. An AD 
converter theoretically* adds noise with a RMS value of 1/sqrt(12) the 
level of 1 bit. Take Warp's 24 bit converter. Assuming an input level of 
+- 1 V the noise added by the AD conversion process is about 34nV RMS. 
In order for an analog system to rival that it should add less than 
that. Take again Warp's 96 kHz sampler, if correctly designed that will 
have a bandwidth of about 25-30 kHz, any resistor in the amplifier that 
is larger than 4 Ohm will add a thermal noise that exceeds the 
specification. In short, IMHO it is not impossible and 24 bit is overkill.

* Assuming it meets the specification of linearity and no missing codes. 
I still have to meet one that does. *And* assuming the internal analog 
components are better than that 34nV.

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