I wrote:
>> I sure would like to see a block diagram of the entire Hi-MD input
>> stage. I tried all kinds of search combinations with no luck. Anyone
>> luckier than me?
stoatwizard replied:
> I have the service manual for the NH700. Downloaded from those nice
> chaps at MDCF, They imply that the RH-1 uses the same part
>
> http://forums.minidisc.org/index.php?showtopic=16220&st=0
>
> which is worth knowing before splurging on one, though the improved
> operational controls are probably worth it even is sound quality is
> probably similar :)
>
> The analogue input stage and ADC is the AK-5356VN-L. Read more about
> it at http://www.analogzone.com/avp_0804.htm
>
> You can see the datasheet at
>
> http://www.asahi-kasei.co.jp/akm/en/product/ak5356/ak5356_f00e.pdf
>
> And the surmise that the hi/low sensitivity is achieved by gain
> variation rather than a input pad is borne out on page 14. The
> feedback resistor of the non-inverting preamp can adjust by software
> the gain to 13,18,28 or 33dB. We presume Sony use the 33dB and 13dB
> gains for Mic-Hi and Mic-L respectively, which is why there is a 20dB
> difference between the two.
>
> That lot should address your curiosity on the innards of your MD ;-)
Thank you again! Your surmise helps distill it down. I also appreciate
your operational bottom line advice... to down shift to "Low Sens" when
hitting full scale with level setting of <12.
Curt Olson
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