Re: Audio quality degradation over FM transmission

Charlie Edmondson <edmondson@xxxxxxxx> wrote:
> kristian.hermansen@xxxxxxxxx wrote:
>
>> Ian Stirling wrote:
>>
>>>For a good signal, pretty much the only thing that you could notice is that
>>>the bandwidth is a bit lower, as the FM signals bandwidth is about 15Khz,
>>>compared to the CD bandwidth of about 20Khz.
<snip>
>>>These are generally designed down to a price, not up to best audio quality.
>>
>>
>> What if I had a high-quality transmitter?
>>
>> Kristian Hermansen
>>
> Nope, the MP3 player doesn't have that quality. The reason there are
> MP3s is because of compression, they eliminate some of the 'unneeded'
> data that is stored on the CD so that it will take up less space. This
> compression means that there is more noise and less dynamic range in an
> MP3 than the original. You also loose some of the highs.

Which is usually unnoticable, except for the lowest bitrates, and the
best listening conditions.

>
> Next, you have your MP3 player. When he said designed down to a price,
> he was talking about the MP3 player, not the transmitter. They often do
> not have the 'best' audio stages, being just good enough to not sound

I've measured the outputs of my cheap MP3 player with single tone outputs.
It vastly outperforms my ears, and shows good results on test equipment,
coming up with a dynamic range of about the same as my CD player.

Many/most low-power FM transmitters are of very bad quality, and come
nowhere near what FM can achieve.
.

Relevant Pages

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