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What is the least compressed signal?

Hello everyone.I was wondering what everyone's thoughts might be about what is the least compressed front end signal? A friend of mine recently told me that radio signal is compressed. So I thought maybe a direct connection to a CD player? Or, since CDs are pretty compressed, maybe a record player? Thoughts?
the reason I ask is, my friend recently gave me a fantastic pair of speakers. And I've been listening to the radio through them. He had a disgusted look on his face and told me I was not using these speakers how they were meant to be used, because the radio signal is kind of crappy and compressed. I would love to use the speakers as they were intended. Meadowlark kestrel hot rods hooked up to an Integra receiver w/ kimbers
ddjr
n80
2,117 posts
 
Agree with Geoff on the top two paragraphs. kosst seems to be missing the point. As Geoff says, what the DR database data shows, correlates almost perfectly with the listening experience. It is eminently useful in that practical application regardless of technical minutia. And for the end listener that makes it the most valuable and accurate tool available to assess DR compression prior to purchase.

As for Geoff's last paragraph, it seems "quibbling" remains necessary. The severe and even moderate dynamic range compression on so many CDs is due to a dubious practice, not a limitation of the medium itself.


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cleeds
5,967 posts
 
kosst_amojan
Bass is this giant, power sucking waveform that would send the needle sailing off the surface and crashing into the record were it physically represented in accurate proportion to the treble. And the treble is cranked WAY up just so the needle can pick it up ... the massive pre-amp connected to the needle that undoes an insane amount of dynamic compression ...
That is a very colorful dramatization of the LP process but it doesn't really mean anything. There's nothing at all insane about the RIAA curve and if you disagree, then you'd have to acknowledge that it's a pretty simple, straightforward process when compared to something such as CD, which relies on things like block-based error correcting codes, filtering, complex servo mechanisms and the like.
The only conclusion I can come to given the facts is that people generally like a dynamic range limited to about 60 or 70 dB, which would explain why some like vinyl with it's limited range so much.
Actually, a 60 to 70 dB dynamic range is quite broad - much more so than you'll find on most CDs. That's the simple fact you're choosing to dismiss. It's rather moot that CD is capable of much greater dynamic range because it's rarely needed musically, and even more rarely actually utilized. If ever.
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cleeds
5,967 posts
 
n80
kosst seems to be missing the point. As Geoff says, what the DR database data shows, correlates almost perfectly with the listening experience.
Exactly! And if kosst actually bothered to consider some of the data and listen for himself, he'd understand that. That doesn't mean that the database is perfect, but it's certainly useful.
erik_squires
16,212 posts
 
What is dynamic compression if it's not equalizing all of the wave forms to have a uniform amplitude? That's EXACTLY what RIAA equalization is designed to undo.

Hi kosst,
Sorry but the RIAA curve does not alter dynamic range, nor does it attempt to reduce all wave forms to a uniform amplitude.

Look at it this way. If I turn the treble down on my amp, I have not altered the dynamic range, at all. The tweeter now just plays 4 dB softer than it did before, but the range, the delta between softest and loudest, remains up to the music. 

Best,

Erik
erik_squires
16,212 posts
 
Without even going into room acoustics and vibration isolation and rf, the primary culprits are the stray scattered laser light getting into the photodetector and the vibration, wobbling and fluttering of the disc itself. Both of those problems together I estimate to constrain and limit full dynamic range by at least 3 to 6 dB, probably even more.


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