Higher Output impedance, better?

jenson

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Player A (CD player / Dac) - 47 ohms
Player B (CD player / Dac) - 76 ohms

what would be the primary difference one would notice
 
What is the typical output impendance of a CD player and what it constitute... Gain or volune...
 
Output impedance (Z) in isolation doesn't give the full picture.
When two devices are chained, like in an audio rig, the source has an output impedance and the destination has in input impedance.
In theory, for max transfer of power, Z(out) should be 0 and Z(in) should be infinity.
In real world, Z(out) should be low and Z(in) should be high; like order/s of magnitude high.
An acceptable ratio when using chains of SS equipment is Z(in)/Z(out) = 10

Eg.
CD player Z(out) = 76 ohm
Preamp section Z(in) = 20 Kohm
Z(in)/Z(out) = 260 (much higher than 10)

This chaining will have very less power loss during transfer of signal.
If the ratio is very low, the source will start seeing the destination as a load and it may affect gain/volume/performance.
This matching was important in tube systems due to output coupled components like transformers, etc.
In the SS world today, one doesn't need to worry about this. The ratio is most of the time orders of magnitude.

Cheers,
Raghu
 
Thnx for such detailed insight!

Could you pls elaborate further wrt tube amps, what should one take care of.. Especially let's say integrated tube amps.
 
Thnx for such detailed insight!

Could you pls elaborate further wrt tube amps, what should one take care of.. Especially let's say integrated tube amps.
Just use the "rule-of-thumb" stated above. Ratio of Z(in)/Z(out) > 10
Cheers,
Raghu
 
Perfect, could you incorporate input impedance in this calculation, any such calculation..
 
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