Help with compression and dynamic range


I'm 51. After a 15 year period of dealing with mortgage payments and childcare needs, I'm trying to get back into higher-end audio quality - especially when it comes to dynamic range in concert DVDs. I've recently spent countless hours trying to research CDs, MP3s and compression issues - with no resolve.

How can I tell which concert DVDs offer wider dynamic ranges? Or, for that matter,CDs? Is there a rating on the covers? I'm willing to do my homework if anyone can give me a reference. I've just read "Get Better Sound" by Jim Smith with no resolve.

Also, I'm looking to purchase a DVD player which will maximize sound quality when I can determine which DVDs and CDs are recorded with minimum compression and wider dynamic range. Can anyone explain what to look for when purchasing a higher-end DVD player. I've seen ratings for DACs, but am unsure what they mean.

ANY help is appreciated.
kewadinbob
Whty do you think that the problem lies solely with the software CDs and DVDs? It may be your speakers.
Speaker/amplifier match is the main thing to get right in order to optimize for dynamics.

Source quality is important also but tends to be less problematic overall and only matters after you get the speakers and matching amp right. There are many ways to go wrong there! Main thing is to assure amp clipping is avoided at all costs and that speakers are up to the task of delivering what the amp then provides.
Hello youngster, re concert DVD/Blu-rays most recent ones have better specs than cd's and sound very good. I do not think the specs are printed on the jackets, etc but your player / TV should display the specs if there is a menu choice for it. What music do you like - I can post a few good ones if we have similar tastes.

Re a player, many will point you to an Oppo machine. I am happy with my Sony (have 2) and it only cost $150 or so. Look for units that have analogue outs to connect to your system.
"Source quality is important also but tends to be less problematic overall and only matters after you get the speakers and matching amp right."---Um, source quality is the #1 issue. If the source is greatly compressed it's over. The music is not going to sound dynamic. Obviously a better system well matched will enhance dynamics. If you don't care about dynamics source may not be as big a problem but some recordings are so compressed they are close to unlistenable. This guy obviously cares about dynamics. I don't know how you find dynamic sources other than reading what other people think of the recordings. Beware of someone who just says it sounds really good and clear. That tells you nothing about dynamics or compression. Eventually someone will mention compression and if they say it is, then it probably is.
You might try an old DBX compresser/expander but, of course, you are then introducing more noise and distortion into your system.
Look for an amp with 3db or more headroom...to simplify it...NAD amps are known for this...as others...
IMHO, you'll want a Bluray player for video and audio discs (Oppo is a popular choice). At that point you'll buy the discs of your favorite artists and that's what you will be stuck with. Some will be good and some wont. You wont know until you get them home and play them on your system. You'll find that the sound quality of a video is just one part of the video experience and that the video production, camera work and performance are just as important for a rewarding viewer experience. Dynamic range will be far down the list of important criteria.
Can anyone explain WHY they would compress a recording ?
What is the purpose ?
I find it extremely aggravating and the ruination of good music !
I hear it not only on digital music but analog (LP) as well .

Happy Tunes
One valid reason to compress a recording is so they can be heard better over background noise. Only audiophile types lock themselves in quiet rooms when listening to music.
Synthfreek ;
Do you believe that cutting off the highs and lows makes the music sound better , on your equipment , than recordings that don't reduce these extremes ?
Just curious .

Happy Tunes
Compressors and limiters (very fast acting compressors) are required so that music can be comfortably transposed or carried by the medium. They reduce the musical peaks and raise the low level signals. For instance, on vinyl records if the music is recorded too softly it can be overwhelmed by the noise floor. If too loud, playback time per side is greatly reduced and the stylus may literally pop out of the groove. FM radio and reel to reel tape also have dynamic range limitations that virtually mandated the use of dynamic compression in order to fit the music within the medium.

With modern digital recording and playback equipment there's no technical reason to use compressors or limiters. However, in pop/rock recordings there are any number of artistic reasons to use compressors. Bonham's classic drum sound or Santana's mid-to recent period guitar tone are dependent upon compressors.

To address Saki70's question: some music just doesn't sound right without compression. Rock without compression doesn't sound like rock and roll. Do you really want to take the crunch out of the guitars?

One of the tell tale signs of an untrained musician is their wildly fluctuating dynamics. Such dynamics are also considered a sign of poor recording engineering. In a single recording the music shouldn't be so soft that you turn the volume up and then later have to turn the volume down because it's now too loud.

Compressors and limiters I'm referring to are conceptually different than and have nothing to do with data compressors such as MP4.
Onhwy61 ;
Maybe we are talking about two different things here .
What I am referring to when I speak of compression is the
omission of the highs and lows . This is what is done , as you mentioned , on FM radio . I get the same kind of reduction on some CD's and LP's . It kind of sucks the life out of the music . It is akin to putting a blanket over your speakers . And then on other recordings the highs and lows are present and the music just sings ! Not so much about the dynamics or loud and quiet passages but the extension .

Thank you
Kewadinbob ;
Doing your homework will consist of reading recording reviews , if you can find them , or just taking a chance . There may be 2 , 3 or more prints of the same album that may or may not contain the same sound qualities often from different manufacturers . I've had three different prints of 'Dark Side of the Moon' on CD . They all were compressed . I have a LP that is not . I have George Harrison 'All Things Must Pass' LP set . The first song on side A of the first record is pretty good . All of the rest of the songs are compressed ! It sounds like somebody covered the mic's .
My experience has shown it to be pretty much a hit and miss situation . I hit the thrift stores to try them . Then donate the misses and keep the hits , sometimes having to repurchase better condition copies from resellers .
Good luck and enjoy the hunt !
This is the first time I've ever heard compression defined as "the omission of the highs and lows."
Some of us have different definitions for terms than others .
I look at compression as taking away the highs and lows and compressing the audible signal into a narrower frequency range . For instance reducing a 20hz.-20k.hz band range ( an average audible range) and compressing it down to say 150hz.-16k.hz.
I am not ignoring dynamics , soft to loud . It's just that I find compressing the audible signal range to be more deleterious and experienced more often .
But this discussion is off topic .

Happy Tunes
That's not a definition of audio compression. What you're referring to is bandwidth limiting. In the example you suggested 3 octaves of bass, but less than a half octave of treble are removed. With anything approaching a full range musical passage that level of bandwidth limiting would sound unnatural.
Onhw61. You're right. Compression is basically making the softer parts of the song louder so that there is no longer any or little volume difference between the loud and soft passages. That's why it's called the loudness wars. It's worse when they kick up the volume of the loud passages too. Then you barely need to turn your volume knob and it's blasting horribly. I did read an article that the recordings today are made to sound better on poor sounding equipment, ear pods, car stereos etc., where you wouldn't be able to hear the soft passages very well on low compression recordings.
You are at that age where your hearing could be deteriorating perhaps you should get a hearing test? Hope you find your problem soon. Best of Luck
Different strokes for different folks .
What I am referring , to by whatever term , is indeed very real .

" With anything approaching a full range musical passage that level of bandwidth limiting would sound unnatural. "

And that sir is exactly what I have been describing !

Happy Tunes
But compressing is not limiting the high frequencies or the low frequencies. It is raising the volume of all frequencies of the soft passages of a song so the volume equals that of the loud passages of the song.
Ok , I'll bite . Just to get this thread back on course to help the original poster .

What do you call the act of limiting the high and low frequencies ?
"What do you call the act of limiting the high and low frequencies ? "

I'd call it "filtering".

The term compression relates to dynamic range. It should be easy to verify this with a good Google search. I'd start with Wikipedia.
But you are the one who took the thread off course Saki by creating your own definitions to common audio terms. You're making it sound like you're being the moderator and getting things back on track when it was you who caused the derailment to begin with.
Ok , I was using the term incorrectly . Case closed .

Kewadinbob ;
I apologize for your thread getting hijacked .
Please stay tuned .
Kewadinbob ;
Try these , they are a start .

http://www.audioholics.com/music-reviews/allContents

http://www.avsforum.com/t/1393736/top-10-albums-for-sound-quality-in-discussion

Good luck .
I was just thinking about this last night after the CSN show I attended. It occurred to me that the dynamic range is what gives the music life, the organic feel it produces. When compressing the dynamic range music just isn't the same. Maybe this is why so many prefer live music over recorded.
Or live recordings over studio; I realize live recordings are compressed too but I seem to prefer live recordings. Is it the "sense" of dynamic range, arrangements of songs, the more raw and powerful feel of live? I don't know.