The aptX website says that aptX HD is backwards compatible, but the extend of this compatibility does not seem to be defined for customers.
I am considering the Sony WH-1000XM2 headphones. If they support aptX LL then my decision is made. If not, more thought is needed.
Thanks
Oh I just realised I put this in CD-R hardware. Could a mod please move it for me? Thanks
You put it in the right place. "CD-R *and* Audio Hardware".
Sony says SBC, AAC, aptX, aptX HD, LDAC
https://www.sony.com/electronics/headband-headphones/wh-1000xm2/specifications
Qualcomm doesn't list the Sony
https://www.aptx.com/products?field_aptx_type_tid=484
Given the limited number of products supporting aptx LL, do you have a sender supporting LL?
My question is more concerned with whether the aptX HD spec includes compatibility with aptX LL and whether this is the reason that aptX LL is not listed separately.
My question is more concerned with whether the aptX HD spec includes compatibility with aptX LL and whether this is the reason that aptX LL is not listed separately.
Since one is a lossless codec and the other is a low latency lossy codec, "backwards compatibility" probably means that if one is not supported, it will fallback to whatever common formats are available.
Since one is a lossless codec
Is aptx HD lossless? Where this info from? I can't find info that it is lossless on Qualcomm site (https://www.aptx.com/aptx-hd or https://www.qualcomm.com/products/features/aptx). It only says "Data rates: 576kbps". Lossless with 576kbps?
I’m afraid history is repeating itself.
APT is a lossless low latency codec developed by CSR.
When they introduced aptX the claim was CD audio quality over Bluetooth.
This made a lot of people believe aptX is lossless.
What is CD quality?
Is it a mathematically lossless transmission or a perceptual lossless transmission.
With a data rate of 352 kbs obvious not mathematically lossless.
Perceptually lossless, why not, high bitrate MP3 (320 kbs) is also very hard to distinguish from the original.
The same applies for aptX HD, it supports 24-bit 48 kHz.
Makes one believe it is lossless too.
With a data rate of 576kbps it is unlikely to be mathematically lossless.
Since one is a lossless codec
Is aptx HD lossless? Where this info from? I can't find info that it is lossless on Qualcomm site (https://www.aptx.com/aptx-hd or https://www.qualcomm.com/products/features/aptx). It only says "Data rates: 576kbps". Lossless with 576kbps?
Wikipedia says its a rebrand of APT-X Lossless after qualcomm bought the technology, which is a hybrid lossless codec (presumably not all of the residual signal is sent when the lossless bandwidth exceeds the channel's bandwidth). The features look very similar, so I think this is correct.
No they do not, unfortunately.