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From: Patent Tactics, George Brock-Nannestad

Hello, again,

I did not express myself very clearly when I wrote:

(on the extra-low output from the linear preamp at very low frequencies)


> So, we have to amplify, boost, it, either in the pre-amp or
> digitally, by shifting the digital words representing this low frequency
> "to the right". The least significant bit now represents a higher step, so our
> resolution in the digital representation has suffered.
 ............. 
> I do not really see in which way this loss of resolution should have any
> practical importance if you use 24 bits, unless it is because the 24 bits 
> are not accurate as to resolution when you go below 14-16 bit at the sample
> rates used. In other words, if the steps that are not at all equidistant when
> you get into the less significant bits suddenly mean more, then you have non-
> equidistant steps at levels where this becomes audible distortion. So my
> question is: is this the most plausible explanation for digital EQ
> sounding worse?

----- it is actually the other way round: the low level input has only 
exercised the least significant bits, and if each small step is not identical 
from time to time and does not provide the possibility of providing a 
staircase with uniform steps, then we have a digital word representing that 
sample with an erroneous reference. When we shift everything to the right 
(i.e. multiplying it by 2 for each shift), then these erroneous steps 
suddenly represent something that the D-A converter has a good reference to 
and is much more able to provide with uniform steps. However, in order to be 
a correct multiplication the steps should have been unequal to the same 
extent that they were when the A-D conversion took place. And so we get 
distortion. And the zero-crossings must become doubtful.

Kind regards,


George