-=> Quoting Vladimir Koptev to Cameron Hall <=-
 VK> Hm... I've always thought that Dolby B is a compression/expansion
 VK> system, too. Am I wrong? And whether Dolby C system is just a pair of
 VK> Dolby B systems, working in two different frequency bands?
 
They both are a form of "modified companding" but much more sifisticated
as both level and frequency response are modified.  B type mainly
acts on upper frequency ranges and C type is broad banded, but still
dynmically alters the frequency response also.
 VK> One another question: I know that recording/playback channels must be
 VK> absolutely equal to prevent losses when using Dolby B and especially
 VK> C. But during using tape deck, heads (both recording and playback) are
 VK> wearing and loosing their perfomance. So the characteristics of
 VK> recording/playback channels would not be the same. I wonder, how much
That is true.  However, that is why most 3 head units allow either
automatic or manual setup to deal with both the differences between tape
brands and also different manufacturing "runs".  Also, the aging of the
componants can also be compensated for.
 VK> time would pass before this effect take place? (I have AIWA ADF-850
 VK> deck with "super DX" heads). 
I think that was then next model line to supercede mine.  That "super DX
head seems to have done very well in the wear department.  I keep mine
extreamly clean so it's done very well.
See ya, Cameron Hall
cameron.hall@bluebeam.gryn.org | ad121@freenet.hamilton.on.ca
Blue Beam BBS | 905 662 5784 | Stoney Creek Ontario Canada | v34 vFC FAX
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