--- 1GDW <> wrote:
> I asked a question about LINE OUT on mini disks and have done some
> more investigating. Bear in mind that I am not experienced with
> circuitry. I am using a Sharp DR-7. The manual does not give
> explicit directions
> regarding LINE OUT but in the specifications it lists a value for
> the LINEOUT.
> Specified output
> Maximum output level Load impedance
> Earphones - 8 mW + 8 mW 32 ohms
> LINE 250 mV (-12 dB) - 10 k ohms
>
> Are these different values?
8mW into 32 ohms is about 506mV
250mV into 10k ohms is about 6.3mW
What is the meaning of the -12dB for the line out reference? Are they
saying 250mV when the signal is -12dB below full scale? If so, then at
0dB full scale the line out would be 1 volt.
Also, the 8 mW for earphones should state the % distortion to be
meaningful. The apparent output power can look very different (much
larger or smaller) when distortion is specified.
When you use the 'line' output, can you adjust the output level with
the earphone volume control? On my sony d7 portable dat the same jack
is used for earphone and for line out, but there is a switch to
determine which type it is. When switched to 'line' the output cannot
be adjusted.
A 'headphone' output makes a fine 'line' output as long as the driver
circuit can output sufficient voltage (usually they can). A dedicated
'line' output may not make a useful 'headphone' output if it cannot
drive the lower impedance load (32 ohms vs 10k ohms).
bret
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