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matching amps input voltage to source output volta

If I have a digital (cd) source that has a max output of only 0.5 volts driving a SS power amp directly ( cd has digital volume) which has a power rating of 100 watts at an input voltage of 2 volts.
So how much power is the amp actually capable of. Is it for example only 25 watts max ?( a quarter) or does it not work that way.

I ask because with these settings above my Wadia 381's volume levels can be used between the mid 80s to high 90's ( max is 100) which I know is good.
But alternatively I could either increase my cd's output voltage to 1 volt or lower my amps (Nagra PSA) input voltage to just 1 volt to get a better input /output voltage match and hence more available watts if needed for sudden peaks?
But then the volume on my Wadia goes down to between low 70s to mid 80's which means more digital bit loss .So which on paper at least is the better option. Thanks.
( please do not recommend a separate line stage an I have no more money!)
128x128pcoombs

Showing 2 responses by pcoombs

pcoombs's avatar
pcoombs OP
84 posts
 
Thanks Al for the info.
If I'm right by changing my amps input voltage down to just 1 volt ( instead of 2) I'll get about 25 watts available of my amps 100watts rather than just the six I was currently getting. I think my Speakers (Harbeth M40.1s 84db) would appreciate a little more!.

Maybe I should also change my Wadia's output up to 1 volt to match the amps 1v input but I'm sure this would then put my volume range around the 50s-60s and wadia recommends 75+ as below will start 16 bit loss (although your posts suggests it could be a lower volume level before this happens.

Its interesting that most people and Wadia encourage owners to change the internal voltage settings to enable the volume control to stay as high as possible and above 75( which surely in most cases would be to a lower voltage than the amps input voltage) but do they realize that by doing so they are seriously reducing there amps output as in my case from 100 watts available to only 6! I certainly didn't.

As Harbeth recommends between 50-150 watts Maybe i need to get a 200-400 watt amp with an input voltage of 1 volt to enable me to still get my 50-100watts!
pcoombs's avatar
pcoombs OP
84 posts
 
Thanks again Al for taking the time explaining all this. I'm not very technical minded .But yes I am using XLR cables mainly because the Nagra amp only has these available on back ( supposedly due to lack of space which does seem odd as they have generally recommended single ended conections!).

don't know if I'll be able to find out how Nagra defines its inputs as they don't always respond to questions but I'll try asking them .
All I know about the Wadia is that there is no change in volume levels (unusual) when switching between the rca and XLR outputs ( this has been confirmed from may other postings) whereas I know for most cd player etc the balanced output is 6db louder. But I think the Wadia is still a 'proper' balanced design but not certain.

One other question/ if what you suggested is possibly the case what amonut of powers is my Nagra possible capable of with the wadia at 0.5 v and the Nagra at 1 volt (we think 25 watts presently but maybe moreif what you said above is infact the case
)Thanks again Philip.
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