[neil74]

As someone who regularly switches between an idevice and Droid (currently p2xl and ipx) I think that the lack of aptx is preferable to the lack of aac.

Using say an aac only headphone on Android will probably be close near as damn it to aptx especially if listening to aac files (apple music, Amazon or tidal non HiFi). Whereas using an aptx set with no aac (Sennheiser!) Will likely be noticeably worse on an iPhone?

This of course assumes compressed files rather than lossless.

 

[Monstieur]

AAC is superior to aptX in every case, with the exception of aptX Low Latency for apps and games. The source format is also irrelevant since AAC @ 256 kb/s is transparent, so even with lossless files AAC will be audibly better than aptX. aptX HD is a marketing gimmick since high resolution and bit-depth are useless on a playback device - they are only useful for audio editing.

 

[LajostheHun]

AAC is superior to aptX in every case, with the exception of aptX Low Latency for apps and games. The source format is also irrelevant since AAC @ 256 kb/s is transparent, so even with lossless files AAC will be audibly better than aptX. aptX HD is a marketing gimmick since high resolution and bit-depth are useless on a playback device - they are only useful for audio editing.

This is the science forum so you will need to back up those claims....

 

[bigshot]

I’m not familiar with aptX, but if it achieves audible transparency at a bigger data rate than AAC 256, then it’s safe to say that it’s inferior for playback of music intended to be heard by human ears.

 

[LajostheHun]

I’m not familiar with aptX, but if it achieves audible transparency at a bigger data rate than AAC 256, then it’s safe to say that it’s inferior for playback of music intended to be heard by human ears.

These codecs works differently from one another [AAC/Aptx]so they can't be compared directly like that and making blanket statements .Aptx splits the audio into 4 different sub bands and apply data reduction independently from one another, AAC works differently much closer and basically an improved version to MPEG and MP3 . All this reminds me of the old DD/DTS debate, where people just made up a bunch of incorrect theories why the preferred DTS over Dolby.

 

[bigshot]

Audibly transparent is audibly transparent whatever way they achieve it. Is aptX audibly transparent at a particular bitrate?

 

[Monstieur]

Audibly transparent is audibly transparent whatever way they achieve it. Is aptX audibly transparent at a particular bitrate?

No it's not transparent at the default bit rate (whatever that is) and you can't change the bit rate on most aptX transmitters. It has audible artefacts on certain low frequency notes. I believed it was good enough until I heard a particular song where the low notes distort on aptX but not AAC, and now I can't un-hear it.

However, I archive in AAC 256 and not lossless so if there were artefacts in AAC I wouldn't know from my library. But it's reasonable to conclude that aptX is objectively inferior to AAC 256.

 

[castleofargh]

Audibly transparent is audibly transparent whatever way they achieve it. Is aptX audibly transparent at a particular bitrate?

it's often hard to test, what would we use to know what the transparent sound is like? the headphone wired? almost never sounds right because the headphone is built to work with the internal crap it has. so you can never be sure the difference comes from the codec and not the change in DAC and amp.

No it's not transparent at the default bit rate (whatever that is) and you can't change the bit rate on most aptX transmitters. It has audible artefacts on certain low frequency notes. I believed it was good enough until I heard a particular song where the low notes distort on aptX but not AAC, and now I can't un-hear it.

However, I archive in AAC 256 and not lossless so if there were artefacts in AAC I wouldn't know from my library. But it's reasonable to conclude that aptX is objectively inferior to AAC 256.

disagree with your last sentence. your experience is anecdotal at best when it comes to judging the codecs in general. I'm not saying it's the other way around for superiority, only that your setup is at best conclusive for your setup until we have more data.

 

[Monstieur]

it's often hard to test, what would we use to know what the transparent sound is like? the headphone wired? almost never sounds right because the headphone is built to work with the internal crap it has. so you can never be sure the difference comes from the codec and not the change in DAC and amp.


disagree with your last sentence. your experience is anecdotal at best when it comes to judging the codecs in general. I'm not saying it's the other way around for superiority, only that your setup is at best conclusive for your setup until we have more data.

I forgot the name of the test which measures audio codec transparency. I believe it begins with the letter M. 5 is a perfect score and is transparent to humans. AAC 256 got a 5 (or very close), AAC 128 a 4.something and aptX even lower. The scores were calculated from multiple people.

In my case I'm using a Sony MUC-M2BT1 connected to my Shure SE846. It's not scientific grade, but the same amp and DAC are used for both aptX and AAC. If the aptX decoder is flawed I still consider the comparison valid because aptX was designed as an end-to-end hardware codec to be licensed to manufacturers of transmitter and receiver chipsets, while AAC is only an algorithm. A failure in any part of the chain is a failure of the aptX ecosystem.

 

[castleofargh]

whether AAC is indeed superior is not what I reacted to. you mentioned your anecdotal experience, then went from that alone to conclude it was objective evidence of AAC's superiority. it's a logical fallacy.
if I had to judge aptx based only on using it with my sony A15, I would agree that it's a crap and have no opinion on AAC because that's not an option on the A15 ^_^. but then I used aptx on my cellphone, it worked just fine and sounded pretty much the same to me as other options. one isolated experience is not necessarily more than that.

 

[bigshot]

it's often hard to test, what would we use to know what the transparent sound is like? the headphone wired? almost never sounds right because the headphone is built to work with the internal crap it has. so you can never be sure the difference comes from the codec and not the change in DAC and amp.

You do a simple listening comparison test. DACs and amps aren't going to introduce compression artifacting. If you can hear compression artifacting, then you can be pretty doggone sure the codec isn't transparent. AAC 256 is audibly transparent. I've done a lot of comparison tests to determine that, So if you can hear artifacting with aptX, it is inferior to AAC 256.

AAC192 is audibly transparent on just about all music but there are exceptions. AAC128 sounds good but there is a tiny bit of artifacting here and there with certain kinds of sounds. aptX would probably fit in that range somewhere I would guess.

 

[LajostheHun]

Audibly transparent is audibly transparent whatever way they achieve it. Is aptX audibly transparent at a particular bitrate?

That would require extensive DBTs to determine it objectively.

 

[LajostheHun]

No it's not transparent at the default bit rate (whatever that is) and you can't change the bit rate on most aptX transmitters. It has audible artefacts on certain low frequency notes. I believed it was good enough until I heard a particular song where the low notes distort on aptX but not AAC, and now I can't un-hear it.

However, I archive in AAC 256 and not lossless so if there were artefacts in AAC I wouldn't know from my library. But it's reasonable to conclude that aptX is objectively inferior to AAC 256.

All of that is anecdotal and not objective in any form!!!!

 

[LajostheHun]

You do a simple listening comparison test. DACs and amps aren't going to introduce compression artifacting. If you can hear compression artifacting, then you can be pretty doggone sure the codec isn't transparent. AAC 256 is audibly transparent. I've done a lot of comparison tests to determine that, So if you can hear artifacting with aptX, it is inferior to AAC 256.

AAC192 is audibly transparent on just about all music but there are exceptions. AAC128 sounds good but there is a tiny bit of artifacting here and there with certain kinds of sounds. aptX would probably fit in that range somewhere I would guess.

Again one listener's opinion won't cut it one way or another.

 

[Monstieur]

Testing both codecs with the same file on the same Bluetooth receiver is sufficiently accurate, given the degree of audible difference between the codecs. Just like you don’t need the sensors from the Large Hadron Collider to detect something as simple as light in a dark room. Even if the receiver introduced the artefact, it’s an aptX failure because aptX is a hardware codec.

Anything more is just mental masturbation.