They don’t make ‘em like this any more! The do-it-all Denon PMA 850

culturecrammer

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Steve
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Ooh, get you!
Talking of which, another fuse went on the amp today. I’ve replaced it again but something is clearly amiss.  :|   On both occasions I had just turned the amp on and put the stylus on a record. Any ideas? (Apart from faking it to an engineer which currently I can’t do...)

 
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rabidlistener

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Something missing from an Oriental amp of this vintage - Meters! When I had my Accuphase E-202 the meters could be quite hypnotic. Even the Advance Acoustic X-i125 amp I use now has them. They appeal to that section of the community that has no interest in hifi.

Mike

 

ThomasL

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I was lucky to find an 850 a couple of months ago. Really love this amp! About the self adjusting riaa - can anyone explain how this feature is supposed to work? Sometimes (not every time) when I change between my stereo and mono cartridge (both low output mc’s) the volume goes up and down for a little while before it seems to find the right level.
 

oldius

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I was lucky to find an 850 a couple of months ago. Really love this amp! About the self adjusting riaa - can anyone explain how this feature is supposed to work? Sometimes (not every time) when I change between my stereo and mono cartridge (both low output mc’s) the volume goes up and down for a little while before it seems to find the right level.
The amplifier has a separate head amp for the MC input. Here is a quote which might explain:
The gain of the MC head amplifier of the PMA 850 is inversely proportional to the impedance of the connected cartridge depending on the construction principle of the circuit used.
Cartridge impedance and output voltage are almost directly proportional, and the output of the MC head amp is automatically equalized, eliminating the need for extensive volume adjustment for each cartridge.
 

ThomasL

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The amplifier has a separate head amp for the MC input. Here is a quote which might explain:
The gain of the MC head amplifier of the PMA 850 is inversely proportional to the impedance of the connected cartridge depending on the construction principle of the circuit used.
Cartridge impedance and output voltage are almost directly proportional, and the output of the MC head amp is automatically equalized, eliminating the need for extensive volume adjustment for each cartridge.
Thanks, Oldius. I’ve come across this myself. I guess it must be from a Denon brochure. I was just wondering how automatic equalization works?
Did you or anybody else ever happen to find the user manual online? I can only find the service manual?

Best, Thomas
 

It Cost How Much!?!

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Thanks, Oldius. I’ve come across this myself. I guess it must be from a Denon brochure. I was just wondering how automatic equalization works?
Did you or anybody else ever happen to find the user manual online? I can only find the service manual?

Best, Thomas
I think I have a user manual when I got mine. Yep, just found it.
 

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ThomasL

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Thanks, that’s great! Would it be too much to ask you to post pictures of the rest of the manual?

Best, Thomas
 
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