[peskypesky]

Really love how even at 96kbps Opus is still transparent 99.5% of the time, On par with 160k AAC/Vorbis & 192Kbps Lame mp3. Could fit 12,500 Songs on my 128gb card since many of them are either <7 min or 56+ min Noise/Ambient/Noise metal freak outs, Which I'm still floored even possible at 96kbps since HA only expected above 128kbps for it. Wish xHE AAC support grows since that even better at 96kbps with Exhale 1.8.0

With USAC/xHE AAC cue better than FM stereo on AM stations, For the USA.

My ears are getting old (I'm 54) and I went to a LOT of loud rock concerts...so my transparency bitrates are quite low. I've been doing a lot of ABX tests in the past couple of weeks and have found that AAC/CoreAudio is transparent for me most of the time at 128k. Opus at 96k.

It is ASTOUNDING to me that I cannot hear the difference between an Opus file and a FLAC that is 8 times the size. I mean, how can that be possible? One eight the file-size, and I can't hear a difference....

Could I have heard a difference in my teens? Probably. In my 20's, probably. In my 30s, maybe. But I have a feeling that by my 40s, I wouldn't have been able to tell the difference consistently.

And without ABX testing...I would NEVER in a million years have believed this.

 

[Sterling2]

My ears are getting old (I'm 54) and I went to a LOT of loud rock concerts...so my transparency bitrates are quite low. I've been doing a lot of ABX tests in the past couple of weeks and have found that AAC/CoreAudio is transparent for me most of the time at 128k. Opus at 96k.

It is ASTOUNDING to me that I cannot hear the difference between an Opus file and a FLAC that is 8 times the size. I mean, how can that be possible? One eight the file-size, and I can't hear a difference....

Could I have heard a difference in my teens? Probably. In my 20's, probably. In my 30s, maybe. But I have a feeling that by my 40s, I wouldn't have been able to tell the difference consistently.

And without ABX testing...I would NEVER in a million years have believed this.

I just compared and contrasted “Classis Hauser” on LP, CD, 24/96 FLAC, and 256k AAC (Apple Music) via Airport Express, as well as usb to OPPO DAC. I expected the 24/96 would be most satisfactory. This was not the case they all sounded so similar as to be indistinguishable; therefore, I concluded Apple Music from Airport Express being most convenient as well as most inexpensive was the route to take and I’m taking it. Yeah imagine that going with AAC.

 

[sonitus mirus]

Music is a bit like an iceberg when it comes to auditory masking and perceptual coding. While the lossless file may contain the entire "iceberg", the lossy version only needs to make the section above the water visible and behave like a real iceberg. In calm waters this is easier to do than in choppy waters with huge waves; just as certain music can be more difficult to encode in a lossy format without introducing audible artifacts. With AAC 256 or higher, the biggest concern I have personally seen is how to handle conversions of tracks at or near 0 dB to avoid clipping. If clipping is properly avoided, this may introduce slight volume differences with some frequencies that may be detectable in certain situations with a small number of individuals. At least, that is what the research has shown that I have read.

 

[bigshot]

The iTunes encoder tends to boost the level a tiny bit. I've seen hot tracks bump a little into clipping too. I don't think that is AAC doing that. I think it is iTunes.

 

[Plumbus the Wise]

The iTunes encoder tends to boost the level a tiny bit. I've seen hot tracks bump a little into clipping too. I don't think that is AAC doing that. I think it is iTunes.

Boost via compression?

 

[bigshot]

No, just a very slight overall volume boost. Less than a percent, but sometimes it's enough to push into clipping. Rare, but I have noticed it a couple of times on hot mastered albums.

 

[Blackwoof]

Music is a bit like an iceberg when it comes to auditory masking and perceptual coding. While the lossless file may contain the entire "iceberg", the lossy version only needs to make the section above the water visible and behave like a real iceberg. In calm waters this is easier to do than in choppy waters with huge waves; just as certain music can be more difficult to encode in a lossy format without introducing audible artifacts. With AAC 256 or higher, the biggest concern I have personally seen is how to handle conversions of tracks at or near 0 dB to avoid clipping. If clipping is properly avoided, this may introduce slight volume differences with some frequencies that may be detectable in certain situations with a small number of individuals. At least, that is what the research has shown that I have read.

Codecs like Musepack are a odd one, It transparent on really hard samples at 175kbps but being VBR it can use bit rates at 384 ~ 800kbps while AAC 256 only peaks at 495kbps. I have a 30 min track at near the end average 605kbps pretty much near 1mbit. So it a lossy codec that can contain the whole "iceberg" only if it needs too.

 

[Plumbus the Wise]

No, just a very slight overall volume boost. Less than a percent, but sometimes it's enough to push into clipping. Rare, but I have noticed it a couple of times on hot mastered albums.

Well I hope no one plays Californication or Death Magnetic on it...

 

[bigshot]

Though might not hear the clipping through all the clipping. I’ve only run across it in classical music where there is a huge surge in volume all of a sudden.

 

[gerelmx1986]

The iTunes encoder tends to boost the level a tiny bit. I've seen hot tracks bump a little into clipping too. I don't think that is AAC doing that. I think it is iTunes.

I use personally, dbpower amp with FAAK, codec pack, that is AAC from fraunhoffer institut. This is the original German encoder. Better than itunes (american made sidtware)

 

[Sterling2]

Though might not hear the clipping through all the clipping. I’ve only run across it in classical music where there is a huge surge in volume all of a sudden.

I sometimes record iTunes to DAT at 16/44.1 and clipping is apparent occasionally on Dance music as seen from recording level meters when DAT recorder is set for 0 db input.

 

[bigshot]

iTunes is fine for almost all commercial tracks, and normalizing down a hair takes care of the rest. In the real world, causing clipping is extremely rare. I’ve only encountered it in two tracks out of tens of thousands myself.

 

[Sterling2]

iTunes is fine for almost all commercial tracks, and normalizing down a hair takes care of the rest. In the real world, causing clipping is extremely rare. I’ve only encountered it in two tracks out of tens of thousands myself.

Unless you digitally recorded everything you’ve listened to from iTunes you would not know how often you have encountered it.

 

[bigshot]

All my music library is encoded at AAC256 VBR in iTunes. I’ve ripped tens of thousands of CDs. Whenever I encounter clipping when listening, I pull the CD and check the rip against it. That has only happened a handful of times. Usually, it’s clipping in the master. I can only think of a couple of times when it was a sound peak up at 100% that peaked the iTunes encoder. Those were both orchestral recordings. I think they were both on the BIS label. Sibelius? Can’t remember the other instance.

 

[Sterling2]

All my music library is encoded at AAC256 VBR in iTunes. I’ve ripped tens of thousands of CDs. Whenever I encounter clipping when listening, I pull the CD and check the rip against it. That has only happened a handful of times. Usually, it’s clipping in the master. I can only think of a couple of times when it was a sound peak up at 100% that peaked the iTunes encoder. Those were both orchestral recordings. I think they were both on the BIS label. Sibelius? Can’t remember the other instance.

I sometimes record iTunes to a Sony PCM-7010F DAT Recorder, which is set to 0 db input gain. The unit’s meters occasionally reveal clipping, which is too brief to hear. I have only noticed this from Dance genre streaming.