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HUG-1
15-08-2010, 12:15 PM
This thread looks at how audio can been dynamically enhanced to make it sound (and measure) louder.

kittykat
16-08-2010, 01:02 AM
I guess if a recording doesnít distort or have clipped peaks itís still tolerable even if itís heavily compressed.

Unfortunately, loud, squared off peaks are becoming more and more common, even from reputable labels. I was listening to The Policeís 2 early albums on cd over the weekend, and the volume control was cranked up to 10/11 oíclock on the amp. On modern recordings, this would be an ear splitting position.

Out of curiosity I downloaded the top 1300 highest dynamic recordings from dr loudness war info and plotted the distribution across decade of release (it gets a bit more complex due to re-releases) but what I can see is that the highest dynamic range recordings are from the 80ís (we have to remember that this only represents what has been contributed to the database and not a complete picture of every recording made in history). The red lines denote lower dynamic range recordings while the green ones are higher DR ones. The loudness madness looks like it began in the 90ís.

Heavy compression is one gripe but also looks like technology (apple mac etc) has created the backyard/ kitchen table top recording engineer. Imo, they are opposite to the heavily compressed brethren. Some of the Bjorks etc sound like they lack dynamics and bite, as opposed to the excitement of a finished studio product.

A.S.
16-08-2010, 09:29 AM
... but what I can see is that the highest dynamic range recordings are from the 80ís ....The loudness madness looks like it began in the 90ís...Noted. Now for the benefit of our not so technical readers, can we explain exactly what we mean by dynamic range just using ordinary words - with perhaps an example or two? Could you make a snippet from an 80s album you have compared with the same performance on a modern CD? Just 15-20 seconds each would be within copyright law. I can give you a private folder to upload to. Or we can use the Beatles as I wrote about some while back, here.

kittykat
16-08-2010, 10:37 AM
Dynamic Range in a recording is as i understand it, very simply, the difference between the average loudness of a recording (above a certain threshold) and the loudest point. If a high dynamic range recording is like a black and white photo, it will have many shades and gradations of grey in between the lightest and the darkest.

If we average the grey parts of the photo and compare it with the blackest part of the photo, there will be a big difference in value. On the other hand, a low dynamic range recording is like a photo which is very contrasty and lacks shades (once we set the threshold of say discarding the lightest shades). Yes ill be happy to do graphic and audio snippets.

kittykat
17-08-2010, 12:18 PM
a snippet ....compared with the same performance on a modern CD?

The 80's example is small sample from "Pirates" - Ricki Lee Jones, and the modern one is from Janet Jackson's Discipline. A side by side graphic of the 2 samples is enclosed. Both enjoyable listens in their own way.

Paul G Smith
16-09-2010, 06:01 PM
This thread looks at how audio can been dynamically enhanced to make it sound (and measure) louder.
The main dynamic range reducing tool in a recording engineers armoury whether on a desktop or expensive studio is the compressor. Put simply, the way it works is that when the input signal gets louder, it turns the wick down, and when it gets quieter again it turns it back up.
How good or how bad a recording (or amplified live performance) sounds depends on how these things are set.

Paul G Smith
16-09-2010, 07:38 PM
The 80's example is small sample from "Pirates" - Ricki Lee Jones, and the modern one is from Janet Jackson's Discipline. A side by side graphic of the 2 samples is enclosed. Both enjoyable listens in their own way.Techie question : is the visible PEAK level the same for both samples, as the scale is difficult to read?

{Moderator's comment: Please note the Attachment policy.}

HUG-1
16-09-2010, 08:57 PM
Please note that these attachments do not meet the current Attachment policy (applied after they were posted). Attachment policy is here (http://www.harbeth.co.uk/usergroup/showthread.php?980-Posting-attachments-the-importance-of-explaining-by-Annotation.).

kittykat
16-09-2010, 10:33 PM
Apologies, Yes the scale is exactly the same. The fonts are tiny in Soundforge and when i reduce the screenshot to be uploadable, all detail is lost.

Paul G Smith
17-09-2010, 09:05 AM
Apologies, Yes the scale is exactly the same. The fonts are tiny in Soundforge and when i reduce the screenshot to be uploadable, all detail is lost.To me they demonstrate the difference audio compression can make to the average "volume". The Janet Jackson track must sound over twice as loud as the the Ricky Lee Jones, but I bet the percussion sounds much better in "Pirates".