The Apple TV seems like a nice solution to stream Apple Lossless but I’ve never experienced a nice audio quality on mine because it was fixed at 48kHz and my files are usually 44kHz. Maybe that has changed, or maybe there will be a lot of 48kHz files…

Hi Frederik,

Regarding your sampling rate question: I'll write up a blog posting on my website to discuss this. It's too long to put here, and I need to make a bunch of graphs in Matlab first... However, this mistake that most people make is to assume that the only reason to have a higher sampling rate is to have a higher frequency bandwidth with some link to the limits of human hearing - that link is only one of many arguments for and against high sampling rates. It's the easiest one to explain and understand, but possibly the least relevant...

Regarding your bit depth statement: it's standard to use TPDF dither on LPCM signals, so there is no quantisation error on the signal. The quantisation error is randomised and turned into a program-independent noise floor at 6*nbits+3 dB below the maximum possible signal level. So, for example, in the case of 16-bit LPCM, the white noise from the dither is 93 dB below the level of a full-scale sine wave.

HOWEVER (as one example) if you have a 16-bit recording played through a 16-bit DAC to an analogue volume control set so that the sound pressure level of a full-scale sine wave is, say 50 dB SPL (which is a good guess of the level of the radio in the background as I type this on a Saturday morning while half of the house is still sleeping...) then the noise floor is 50 dB  - 93 dB = -43 dB SPL, which is much quieter than the noise of the fridge compressor...

HOWEVER, if I play a recording like the "Banditen-Gallopp" from Telarc's "Straussfest" cd, and I connect the digital output of the CD player to the digital input of a pair of Beolab 90s, and I turn the volume up to maximum, then the spike from the gun firing is going to hit a theoretical 122 dB SPL. This means that the noise floor of the 16-bit recording is 122 - 93 = 29 dB SPL, which is easily audible in the listening room. The 16-bit TPDF noise floor is the weakest link in this particular chain.

And yes, I play that track at that volume level often. It's an excellent demo of dynamic range, the spikes hit maximum - but they're so far above the RMS and they're so short in duration, that there's no harm done to anyone or anything.

cheers

-geoff

laseralex wrote:

Geoff Martin wrote:

(remember that the CD Redbook format is about to turn 40)

I'd feel much better if we could all just pretend it's turning 20!

🙁

The first LP record was introduced in 1948.

The first CD was released in 1983 - 35 years later.

Now it's 2021 - 38 years later - and we think it's news when a streaming service announces that it can deliver CD quality.

Then again, cargo pants are back in fashion according to my son, so I shouldn't be surprised. Time to put away my 78s to make room for the cassette collection coming out of storage. It'll be interesting to hear Falco again after all these years... Rock me Amadeus...

Cheers

-geoff

Hi Geoff,

Thank you very much for you response, I am looking forward to your blog post!

Also a word of appreciation for your blog in general, you provide some excellent material. I regularly refer my students to some of your articles.

All the best,
Frederik 

Does your screenshot indicate that you have listened to Spotify in lossless-16/44.1?

MM

Hi, does it mean that I would be able to appreciate a better sound quality playing Apple music through my ATV connected to my BV11 (via Airplay)?

Thanks

The Apple Music app on the Apple TV gets the streams itself, and not via Airplay from your phone.

You can Airplay other stuff to it but if you are using the Apple Music app on your phone to play to the ATV, the ATV unit will get the stream itself.

i.e. its not playing an Airplay stream.

fredpert wrote:

Hi, does it mean that I would be able to appreciate a better sound quality playing Apple music through my ATV connected to my BV11 (via Airplay)?

Thanks