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1/3 of People Can't Tell 48Kbps Audio From 160Kbps
An anonymous reader writes "Results of a blind listening test show that a third of people can't tell the difference between music encoded at 48Kbps and the same music encoded at 160Kbps. The test was conducted by CNet to find out whether streaming music service Spotify sounded better than new rival Sky Songs. Spotify uses 160Kbps OGG compression for its free service, whereas Sky Songs uses 48Kbps AAC+ compression. Over a third of participants thought the lower bit rate sounded better."
Are these the same people who prefer MP3 Sizzle?
Remember RFC 873!
(although not as low as 46kbps) and reached the same conclusion. Most people vastly overestimate their ability to distinguish tracks encoded at different bitrates. And I've seen study after study that backs this up. This includes self-professed audiophiles, the original authors of particular tracks of music, and so forth.
Mr. Wizard... why is this place called the Cave of Hopelessness?
on how long they've been cranking their music up to 11.
Lacking <sarcasm> tags,
So, 1/3 of people eh? Hardly a damning assessment when your sampling size is 16 people. Besides, most people I know including myself have some sort of hearing damage from the past or don't really know what to listen for when presented with different types of sound.
I would be more impressed if the same encoding format was used. I think both samples should have been ogg or aac and not a mix. If comparing aac at 48 and 160 are the results different? Same goes for ogg at 48 and 160?
People who can't tell the difference have a 50-50 chance of getting it right. Therefore we can deduce that over *two-thirds* of the population can't tell the difference, by adding in the inferred members who couldn't tell, but guessed right.
Do it with 48kbps AAC vs. 160kbps AAC, or 48kbps OGG vs. 160kbps OGG, and you might have something meaningful.
Or, 48kbps AAC vs. 48kbps OGG, and 160kbps AAC vs. 160kbps OGG, if you want a flamewar...
Village idiot in some extremely smart villages.
You blame the sound, I blame the people.
I think they should see if there is a correlation to the preferred quality, and how much auto-tuned "music" the people listen to.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
In a deaf listening test, 100% couldn't tell the difference between a 160Kbps OGG file and a cannon. Though 3% noted the smell of gunpowder.
If the higher compression audio had simply used this $500 Denon ethernet cable, the results would have been different:
http://www.usa.denon.com/ProductDetails/3429.asp
But seriously, can you make a sweeping statement like "People can't tell 48k audio from 160k" if you're also switching compression technologies? OGG vs. AAC is a whole article on it's own, you just muddy the waters by making this about the compression rate.
This is just a new version of the old megahertz myth of the CPU wars. Two different 2GHZ processors from different manufacturers are not equal, we all finally figured that out for the most part, right? Now we've moved onwards... to the Kbps myth?
Yeah, but they weren't listening through Monster Cable, you can't tell the difference between anything without Monster equipment...
Jan
>> 1/3 of People Can't Tell 48Kbps Audio From 160Kbps
Correction: Over a third of participants thought the lower bit rate sounded better.
Those are not the same thing. To find out how many people thought they sounded exactly the same, I would have to RTFA.
There are a lot of things to mention in this article. They are using VERY high end hardware that can interpolate the sound and cause sound clipping (which makes things sound metallic) to be minimized. They also didn't mention what songs were chosen. A lot of music is mastered to sound good on poor quality speakers and thus the 48 Kbps may actually not be the limiting factor.
At least there going to be a new reason to sell audio snake oil now.
From the article: "We dragged 16 people", I'm no stats engineer but isn't that far too low ?
int main() { while(1) fork(); }
I'd pay for it if I got to watch you do a blind listening test.
Thats strange, I find it trivial to identify differing qualities of compression when listening to my music files.
You look down at the UI, and it tells you what the bitrate is.
(Joking aside, I have advocated 128 kbps for years, not because of sound quality issues, but rather because most people own cheap computer speakers and/or headphones. You only get quality as good as the weakest link in the system.)
HA! I just wasted some of your bandwidth with a frivolous sig!
The summary is quite misleading.
It sounds like 100% of the participants could tell the difference between the two encodings, just 1/3 of the people thought the more simple, clean, highly compressed version sounded better. 2/3 of people thought the high bitrate version sounded better.
When choosing compression, the better way to go is to shoot for transparency versus the uncompressed source, not which audio sounds better to your ears.
That's why ABX is the industry standard for compression comparison, not a simple AB test as in this experiment.
Blessed are the pessimists, for they have made backups.
I say the only valid comparison is listening to the live music, vs the digital format. This way you compare to the original and your not just saying which sounds better (which is subjective). I once worked with a audio system designer and everything was tested using analogue formats with various types of music preferably classical because of it's range in sound.
"Of the 16 people tested"
Good-bye.
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Title of article should be: 2/3 of people CAN tell the difference...
AccountKiller
Considering I can buy a 1TB drive for less than $100, I don't particularly care which percentile I might inhabit ... I see absolutely no reason to rip CD's at anything less than 320.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
this summary is misleading. they were asked to choose which they thought sounded better. the listeners DID notice a difference between the two, and for some reason 1/3 of the participants enjoyed the lower bitrate version better. perhaps it had less harsh high tones or something about it was more pleasurable to them... that doesn't mean that the higher bitrate didn't honestly sound more accurate to the source material. Perhaps uncompressed audio should have also been incorporated into the test. If they still choose the lower bitrate over uncompressed, then it's clear that some listeners prefer the song with the changes inherent to compression.
this was a very unscientific study, with a very small sample size, and really shouldn't be front page on slashdot.
frog blast the vent core
I used to sell audio equipment as a teenager and I recall different people had different ideas about what constituted quality audio. Some people liked deep muddy base, other people liked loud midranges, etc.. I think the study's conclusion is all wrong... it's not that people can't tell the difference, it's that people sometimes prefer the lower quality bitrate. Personally, I just want things to sound representative of the real-life equivalent. :)
CNET - Owned by Rupert Murdoch.
Sky - Owned by Rupert Murdoch.
CBS, actually:
http://www.techcrunch.com/2008/05/15/why-cbs-bought-cnet-and-not-the-other-way-around/
If it'd been a Myspace survey or something from the Times, the Courier-Mail or the WSJ, you'd have had a point.
No, just the headline is massively misleading.
The article actually states that people (a) could hear the difference (b) thought the lower bit rate stuff sounded better.
The key being that the two were encoded with two totally different codecs.
Today's low-bitrate MP3/AAC will be tomorrow's vinyl.
I firmly believe that you prefer what you're accustomed to hearing in the first place. Most kids today have grown up hearing nothing better than highly-compressed FM or low-bitrate MP3 music. They don't know anything better, and given the option of hearing better music, perhaps even uncompressed, with a much larger dynamic range and noise floor, they'll gravitate to what their ears and brain have been trained to appreciate.
Tomorrow's world will have "128Kbps MP3 Afficionado" publications extolling the virtues, "warmth", and "naturalness" of the low-bitrate MP3. And audiophiles will pay top-dollar for crippled hardware and overcompressed, undersampled music tracks.
"we tested with Billie Jean"
I don't hate that song.. but as a testing ground for music hardware/software, it sucks. And you should always test with different types of music.
Also, small sample size (16), only 1 song in 2 versions, presumably always in the same order, on hardware that has nothing to do with what everybody uses (does that lessen or worsen compression characteristics ?), no control group (wanna bet that with 2 exact same versions, song A or song B consistently comes out on top ? Coke and Pepsi worked that one out long ago). No indication how responses were collected (group ? interviewer ? biased ?).
made me chuckle. amateurs.
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The tests have to be very carefully set up: double blind, very carefully calibrated audio levels.
Even a 1/3 db difference makes the louder signal sound sharper / higher quality. It's difficult to run a test that won't run into criticism about how it is conducted.
Many technical considerations for this kind of testing but also is the question "Is the difference in quality perceivable?" or is it "Given how people listen, does any difference between the two matter?"
The key being that the two were encoded with two totally different codecs.
Exactly. And as such they are not comparable.
This certainly does not say a thing about the ability of people to distinguish between a good encoding and a bad one when the only information provided was the bit rate.
At best TFA is a testament to AAC. Says nothing about human ability to distinguish.
You can encode a phone call, typically limited to a frequency response of between, roughly, 350Hz and 3,500Hz at 192kbps. Probably 16kbps would suffice.
Sig Battery depleted. Reverting to safe mode.
I was all excited that my new car came with a satellite radio reciever, then bitterly disappointed with the sound quality and didn't subscribe. I'm considering replacing it with an HD reciever, once I hear one to find out what "HD" really means. Satellite radio is utter crap for sound quality.
CD quality mp3 is 320kbps.I can understand not being able to tell 48kbps from 160kbps (especially when a different codec is used for each, the quality of the codec and the configuration of it is key). It's hard to tell the difference between crap and sh*t. The test is only meaningful as a bitrate test if the same codec and encoding settings are used. Otherwise it's apples to oranges. The bitrate isn't nearly as important as how it's encoded unless both streams are done exactly the same way (except for bitrate).
This test smacks of Apple fanboism. Do a real bitrate test using the same codec and settings (outside of bitrate) and I guarantee you'll get better listener accuracy.
Why on earth would you do a bitrate test with two different codecs unless the test was really marketing propaganda for one of the codecs? /filed in the Apple marketing bullshit drawer
This is a codec test, not a bitrate test. As a "can a user tell the difference between these bitrates" test, the results are completely worthless. It's more like a "AAC rulez! look a 48k AAC stream sounds as good as a 160kbps Ogg stream!" /barf
Don't kid yourself. It's the size of the regexp AND how you use it that counts.
Then the summary is misleading in presenting this as a comparison of bitrates. The article is really comparing the audio quality of the two services.
Over a third of participants thought the lower bit rate sounded better.
Another thing is that majority of people actually have quite crappy speakers, atleast on computers. Lower bitrate sounds "better" on cheap speakers because it dumbs down highest frequency changes in the song.
I was going to say I have no idea why they would compare entirely different codecs here. Not to mention that lots of people are simply not audiophiles or not folks with extremely discerning ears to quality. Plenty of people show that AAC/Vorbis is situational and sometimes one can work better or vice versa.
As a musician, I've had lots of times where irrespective of my quality that I play people think everything is amazing/fantastic.
Based on the article, the testing seems to have very little in the way of meaningful results.
A single instance of a single song with two different encoders given to listeners who hear "more bass" as a quality where the results were so close to split (two people shy of 50/50).
To gather meaningful data: songs must be switched quickly: you should go through a variety of materials (it's worth noting that some compressions have more trouble with certain types of sounds than others), and (ideally) there should be a reference from which to work.
The goal of compression, in theory at least, is to maintain meaningful fedility. Yes, that means that "the part we notice most" is most important: but that's no excuse for causeing "a pleasent error" better than "correct reproduction".
Of course, I've never tested these encoders. It's possible that the lower bitrate encoder did a better job.
but my friend, who has been deaf since childhood, does listen too music but from the point of how it feels. His tastes weren't very different from many others of the time period (album rock which has distinctive beats/etc).
Really didn't crank the base, but it was not loud enough that people around him would stop and point, let alone gesture.
I only asked after asking why he played his music so much and my level ignorance about deafness was high enough to ask.
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it said 48Kbps, not kHZ.
Most lossy music formats totally submarine a lot of detail at 48Kbps and I would wager that almost everyone has the auditory acuity to recognize it. They simply don't have the mental acuity to care.
I agree, so much auto-tone (big air quotes) "music" and they hardly notice gross clipping and drastic tone flattening. :-)
There's no news here. The HE AAC codec (called AAC+ in the Coding Technologies implementation, and now called Dolby Pulse after Dolby's acquisition) is a highly advanced spectral band replication codec, and can be pretty darn transparent down to around 48 Kbps. That there was about a 2:1 preference for the high bitrate Ogg in a highly nonscientific small sample size test like this is a yawner. http://en.wikipedia.org/wiki/HE_AAC
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I paid to get my TV ISF calibrated. It looks amazing. But if you brought it inside a Best Buy and sat it next to their other TVs your average Joe would think it looks like crap.
The TV manufacturers increase the amount of blue to make things appear brighter. People's faces turn green so they up the amount of Red. Then they over-sharpen which introduces artifacts and over-contrast which creates banding.
Encoding audio in a lossy format no doubtingly does the same thing. They make sure the music still "pop"s to the point where it is exaggerated causing the music to "sound" better.
The people who say that 48Kbps sounds better than 160 would probably say the same thing compared to the original.
Since the 16 subjects were asked "which sounds better" and were not given an alternative "there's no difference" then it's actually possible that 12 of the 16 thought there was no difference, and so they randomly picked A or B. And 6 picked A.
So it's possible that only 25% could tell the difference and selected the higher bit rate.
Great study. Very Scientific.
This 'test' seems rather lacking. It doesn't note if the AAC is HE or LC. That can have a very big impact on quality as HE takes more processing power but delivers much better quality at low bitrates. Each codec would also have it's quirks and 'tricks' that establish it's strong and weak points. Some people will simply like one aspect of a codecs compression methods over another, whether that pertains to filterout out high frequency, chopping out repetitive or white noise that is typically not heard, or whatnot.
The fact that they also only tested 16 people should tell the rest of the story. It's not even remotely a good sampling of users and considering the source, it probably consists of users who are 'in the know' about compression techniques and what to listen for.
I would be very interested in a larger study with a random sampling of the users of these two services, with a much larger study group to see what it shows.
CDs are encoded at 44.1 kHz, 16-bit stereo. If you do a little math, this comes out to 1.4 Mbps, meaning that to get you audio down to such a low bit rate you need to eliminate 29 out of every 30 bits. If anybody out there is incapable of hearing the difference, they need to go get a hearing test right away, as that level of compression is EXTREMELY destructive to the quality of the audio.
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This test isn't a complete experimental fiasco (like some of the Microsoft-sponsored listening tests that deem WMA to sound as good at 64k as MP3 at 128k).
But there are a couple of significant flaws with it, that make the results pretty useless:
If you want to know about some methodologically-better comparisons of audio codec quality, please see the Codec listening test page at Wikipedia. Full disclosure: I wrote most of this article, and have attempted to compile the results of all the carefully-conducted independent tests that I could find.
Finally, none of this is to say that we should all demand 160kbps streaming audio if 48kbps can be made to sound just as good. It's just that this study doesn't establish that, not by a long shot. The headline is also wrong in claiming that 1/3 of the participants couldn't distinguish 48k from 160k audio: in fact, they preferred the 48k audio. And preferring one format is very different from claiming that it is of a high-fidelity: for example, audio with a compressed dynamic range is by definition degraded, and yet it persists in commercial rock recordings because uniformly loud music grabs listeners' attention more easily.
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You blame the people, I blame the editors.
There is no study here, from TFA (which itself is barely longer than TFS), sixteen people were asked to state which song clip they thought sounded better. I'm surprised the results were better than 50/50. From TFA, all listeners could *tell* a difference and the report was on which one they *prefer*
Really, there's nothing to see here.
+1 Disagree
But, but... in those expensive digital cables a bit is much more 1 than in a cheap cable where a bit is more like... 1-ish. The hardware and software still sees that as 1, but you have to admit it dramatically impacts audio quality to have a true 1 instead of something which is 1 but not quite as 1 as a real 1.
Now if your amplifier was made out of huge tesla coils, a better shielded cable might improve audio quality a bit.
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I think a LOT of this has to do with so many of today's kids not KNOWING what good sound reproduction CAN sound like.
I've been building my stereo system ever since I was a kid. I walked into a high end audio shop at about age 12...and first heard Klipschorn's hooked to McIntosh tube amp, and I couldn't believe my ears...
It was right then, that I started building my system so I could have that some day. And, today...after buying piece here..piece there, deal on this..selling it and improving one piece at time (ok, thieves and insurance helped with the speakers at the end), I almost have that set up.
People that come over and hear it...are often amazed how good it sounds....they often exclaim they hear new things and nuances in familiar songs they'd never heard before.
Sure, I like an iPod, I have a couple of them...a shuffle for the gym, and a classic for travel, in the car..etc. I have good earphones for them, Shure 530's I think....but, I do realize that these are for very POOR listening environments. I try to get my music in the best source I can (this means CD's at this time, can't buy lossless online yet), I rip them to flac for home stereo usage..and decently high quality mp3 for portable use.
Unfortunately, somewhere between now and when I was a kid...people stopped buying good home audio systems. I don't quite know what or what happened. Somewhere along the line...ONLY portable players came into vogue...and it is sad that so many are losing out how good sound reproduction can be. I dunno if it is cause or effect....but, so much of todays music is mixed so poorly, overly compressed with no dynamic headroom anymore. So, maybe there isn't much point to getting good gear, if new music is no longer mixed to get the most out of it.
But, as far as good gear goes....you needn't go overboard on the super audiophile non-sense and voodoo that is out there, but, with respect to solid audio gear...to a certain extent, you do get what you pay for...
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
People deteriorate over time, too.
As a young man, I could tell a difference in the quality of recordings on vinyl or on tape. Today? Meh. I lost a good portion of my ability to hear just by being around 5 inch guns. Lost some more in industrial work environments. Lost some more to big trucks and heavy equipment.
When it comes to music, I'm a rundown old wreck of my former self. *sigh*
All that said, I suspect a lot of other people have similar histories, and yet more people have health problems that contribute to crappy hearing.
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Hertz and bits are independent. You can sample something at 150kHz but then compress it to 14kbps. You can likewise, sample something at 14kHz and then encode it at 1.5Mbps.
There was absolutely no (none, zero) discussion on the sampling rate and I was correcting that.
Not to mention how poorly the results were considered. TFA states that over 1/3 of participants thought 48Kbps sounded better than 160 Kbps, but automatically assumed that meant 1/3 of participants couldn't tell the difference.
I'd be more willing to believe that 2/3 of participants can't tell the difference, and half of the 2/3rds just guessed wrong...
That is a sad state of affairs....
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Pop music is engineered to be played on cheap equipment. After all, that's what most people have. Practically nobody has ever heard Michael Jackson without a ton of electronics between them. You want a real comparison, use classical or jazz, where folks know what a *real* live performance sounds like.
It's also notable that the people who liked the lower bit rate recording said "more bass == better". "More bass" has been the "gold standard" in pop music for a good number of years -- the harder it punches you in the stomach, the "better" it is.
Welcome to the Turing Tarpit, where everything is possible but nothing interesting is easy.
Unfortunately, somewhere between now and when I was a kid...people stopped buying good home audio systems. I don't quite know what or what happened.
Maybe they didnt enjoy it.
Why do you think people enjoy music and songs ? Most likely, not because its reproduced faithfully, or because they care about the nuances.
Almost nobody cares about the nuances, they like beats and bass or dancy tunes, gansta lyrics or love stories, stuff that is accessible and they can relate to.
Sure, some people care about that little uptick from the violin on the 3rd measure of the 6th symphony of whoever that you can only hear with an hi-fi system in a quiet room. But most people just listen to music to either give them some energy for their workout, have fun at parties or concert, or drone the sounds of their miserable commutes, dreary jog run or boring life.
Same reasons people eat fast food instead of fine cuisine I guess.
And the equipment they use. The chain is never stronger than its weakest link. There is no point in testing say 24bit@96kHz uncompressed if the audio equipment cannot deliver it.
People that come over and hear it...are often amazed how good it sounds....they often exclaim they hear new things and nuances in familiar songs they'd never heard before.
Same is true when I turn up the treble, or turn up the bass. I can hear different "parts" of a song. My headphones sound differently than my speakers, both have unique sounds that I hear the song differently. Which version is better is entirely subjective and opinionated to a certain point. Sure, hearing clipping will be a dead giveaway on poor quality, but not when (in effect) the equalizer settings are different from each system.
My brother loves songs with no bass, and higher treble. I prefer songs with middle to lots of bass and middle to no treble. He can hear a song on my speakers and hate it, but take it to his system and love it. Song enjoyment based on people's preferences is not scientific.
Disclaimer: I am not god.
We may not be created equal
But we can be treated equal.
I grew up in the 80s and early 90s and most people I knew just had off-the-shelf radio/cassette/record-players from Target or wherever. Myself included. And the music always sounded good enough. It still does. I had a couple friends who turned audio hobbyist but I never saw the point. They spent loads of money and seemed to enjoy the music less.
And nowadays, emphasis should really be on enjoying music live, anyway. I might be wrong but I expect distribution will bring less and less money, but not less fame - and fame will bring performances and money.
If I want to carry my favorite artists with me, or listen to them at home, I have bigger things to worry about and spend on than the quality of the audio. Good enough is good enough for that.
Not all bits have equal significance. Example: Suppose I have a perfect-fidelity 30-second recording of a pure 440 Hz sine wave. On a CD this would require 16 bytes/channel * 2 channels/sample * 44,100 samples/second * 30 seconds = 42,336,000 bits.
This same signal can be compressed to the formula "L(t)=R(t)=sin(440*(2*pi)*t)*u(30-t)" (where u(t) is the unit step function { 0, t=0 }). Using string representation, this compressed version requires 25 bytes, or 280 bits. In other words, we eliminated 151,199 of every 151,200 bits—and the compressed version actually has better fidelity than the CD version, since it can be losslessly decoded to an arbitrarily high sampling rate.
This is obviously a contrived example, but it suffices to demonstrate the reducing the bitrate, even drastically, does not have to negatively impact the quality of the audio.
"The state is that great fiction by which everyone tries to live at the expense of everyone else." - Bastiat
It's not even "FM" quality, since even on FM, a song that is mastered well will sound very decent and authentic.
It's that the advent of compression in mastering, *in general*, has been so gradual that unless you knew about it beforehand, you wouldn't have noticed it.
Anecdote: I have two friends who heard me complaining about the shitty mastering and compression that has been happening in hard rock and metal for a while now. They finally made me sit down and explain what was happening, and then I found some examples on YouTube for them to listen to (of songs they knew, best of all).
Now they hate me, because now they *notice* it, but can't do anything about it :P
You can have all the greatest audio equipment in the world (leaving aside the argument about audiophiles and their dubiously useful accessories and beliefs about what results in "better audio quality), but the real problem is at the mastering stage, not the consumer output stage.
While I agree that part of it can be blamed on the Loudness War, and that is one of the reasons I prefer buying CDs from local artists as they don't compress the hell out of their music, I have always thought that the bitrate should depend on what you were going to do with the music.
For example, while I'm sure the audiophiles would have a coronary all the music on my MP3 player I've got encoded at 64k. Why? Because I use it when I'm out and about and frankly with all the outside noise I really can't tell enough of a difference to make the larger files worth it. With 64k I have 75 hours worth of tunes on my 4Gb Sandisk, with 1.5Gb left over for adding new stuff. The same goes for my Truck's Sony MP3 CD player, which sounds great but with me needing to hear traffic noise it is more "background" music than actually listening, and the smaller size means i can have just about every song I like to listen to on the road fit onto two CDs.
Now when I'm at home listening on my nice phones I'm listening at 256k, but that is because ALL I am doing at that time is enjoying music and can actually listen to it closely and tell the difference. But if most folks are using these services like radio stations it is probably more "background" music than anything and frankly why waste the bandwidth on something you can't really tell the difference on? Most folks aren't gonna be using audiophile equipment at the office anyway.
I think for most of us, especially those that grew up in the age of scratchy records and fuzzy radio stations most of this stuff is "good enough" for the things we are doing with them. But after helping a friend convert his old LPs to CD and comparing them to the CD "remasters" I have to say what they've done to older music is obscene and has nothing to do with bitrate. They have compressed the older rock albums so damned much thanks to the loudness war that when compared to the analog original they sound like they are being played through a bad compressor foot pedal. All the dynamics are gone and it just sounds...well it just sounds nasty. Compression artifacts from using low bitrates is one thing, but when my 64k rip of his analog still sounds better than the CD thanks to all the compression they used on the master, well that is just sad. Listening to classic Rush and Styx VS the CDs were just like night and day.
ACs don't waste your time replying, your posts are never seen by me.