radiotoday said:
But in reality what we hear at the end through our...TUNER ON AIR, this isnt what the listener is hearing with us. And this is something which - at the most occasions - isnt what we here from the mpx out from any processor. So whats happening is that we are speaking in a way, about what we could do in a ...laboratory, but when the sound goes per example trough a radio link and a fm exciter which isnt dual speed, or , something very ordinary, we use a cheap, second class trasmitter ( since the budget is always ..less then it should), then, we are hearing definately something else then we should.
What i say is this. WE TRY TO SEE THE TREE, BUT WE CANT SEE THE FOREST.
Wow..I like you and Fonorban!
;D
You speak the absolute truth here! Several of my colleagues (who lurk and read, but don't post here) and I were talking about this very topic. Things like STL's, Exciters, THE TRANSMITTER, THE ANTENNA do play a HUGE role in how the sound of the station comes across...and the processor is NOT the end-all be-all in this process.
There's been lots of discussions about what NYC radio station sounded the best back in the day...I kind of giggle to myself knowing that these stations were, for the most part, on the old Alford antenna during the era of the analog boxes, and operating through that complicated combiner, which played games with everyone's sound...some worse than others depending on their particular situation (bandwidth-wise).
This isn't a knock on the Alford system...all combiners do SOMETHING to the audio...just depends on how critical the filters have to be. When the majority of a market's radio stations are all combined like that, all kinds of goofy stuff comes into play.
The bandwidth of the main RF amplifier on the transmitter (and how well it is -or can be- tuned) also plays a role.
How can RF amplifiers and antennas do this to AUDIO?
Because most of audio is in the form of sidebands -- which extend a ways to either side of the main carrier. If the side bands are truncated by "close filters" (tight bandwidth constraints), then the audio quality suffers -- mostly in the form of lost detail (kind of like "vasoline smear" on the high frequencies). Even worse if the filtering is asymmetrical.
Composite and discrete channel analog STL radio links can also degrade audio quality (some by a surprising amount). Especially ones that have been in continuous service with little attention payed to them over the years! Most do have issues passing low frequency square waves...which is not too uncommon to have on the output of audio processors these days!
The typical real world conditions that even the biggest broadcast stations operate in, and the amount of audio quality that is compromised by means out of the engineer's control can be surprising! Some processors tend to perform much better than others when placed in certain situations.
I'm not going to BEGIN to talk about the issues that various FM tuners have that really muck up the integrity of processed audio heard over the air!
PLL's, IF bandwidth, De-Emphasis, 19 kHz pilot filters that start rolling off severely after 10 kHz.
OY! :-X
This is why several of us feel that it is really silly to try to truly judge a recording made in a closed loop test with what you hear over the air. Folks like Goran, Kevin and all
seem to realize this, but many others might not. So, I'm speaking to the "others".
-C