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The Pono Player and Promises Fulfilled

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Re: The Pono Player and Promises Fulfilled

#31

Post by tonyarkles »

badsock wrote: post #24
tonyarkles wrote: post #22

Earlier quoted context omitted.

> Yes, a 192k playback sampling rate is a joke and maybe even superstitious. There's not much of a reason for anything to play back at over 96k and many argue 41k is sufficient for mixed/mastered material. Point granted. Please don't interpret what I'm about to say as audiophoolery. I'm an EE. I haven't worked in audio a whole lot, but I've looked at things enough that I feel like I could do a reasonable job at desig…

But that's why we've got oversampling. The higher sample rate can be in the conversion stage, it doesn't have to be in the transmission format.

I'd be super curious to see what the frequency spectrum of the input files looks like too. If your source material is being directly sampled at 44k1, then you're going to need a brick wall filter on the input of that too (or you can oversample with a high rate ADC and do the brick wall digitally). If the source material is cut off hard due to the sample rate, no amount of oversampling can fix that.

For robustness sake, I really really love keeping as many filters as possible in the "gentle" range of design specs. Sometimes that's not possible, but if it's possible to do it start to finish through the signal chain, that makes me very happy.

Re: The Pono Player and Promises Fulfilled

#33

Post by badsock »

tonyarkles wrote: post #31
badsock wrote: post #24

Earlier quoted context omitted.

But that's why we've got oversampling. The higher sample rate can be in the conversion stage, it doesn't have to be in the transmission format.

I'd be super curious to see what the frequency spectrum of the input files looks like too. If your source material is being directly sampled at 44k1, then you're going to need a brick wall filter on the input of that too (or you can oversample with a high rate ADC and do the brick wall digitally). If the source material is cut off hard due to the sample rate, no amount of oversampling can fix that. For robustness sak…

Agreed, which is why I don't think anyone argues against, say, 192kHz/24bit on the production side. Unfortunately, I think that people look at what the studios use and interpret that as a quality signifier when it really has no use once the signal is mixed down for transmission.

Re: The Pono Player and Promises Fulfilled

#34

Post by bigdubs »

TheCondor wrote: post #29
bigdubs wrote: post #3

Earlier quoted context omitted.

I love vinyl not for the audio quality but for the ritual and commitment of putting the needle down on a side and listening to the whole thing. It's a really nice, anti-add way to listen to music.

That's what is different. When you bought an album, brought it home and put it on, you really relished the moments listening, you put more effort in to listening, you put more effort in to experiencing the entire product... The song ordering, the album art, etc.. U2 gave away a new album last year, it has song great U2 tracks in it, it's a strong album from them. The entire discussion about it revolved around not the…

Yeah most of my friends are content with a laptop with Spotify and a cheap pair of headphones. Definitely a different mentality.

Re: The Pono Player and Promises Fulfilled

#35

Post by tonyarkles »

badsock wrote: post #33
tonyarkles wrote: post #31

Earlier quoted context omitted.

I'd be super curious to see what the frequency spectrum of the input files looks like too. If your source material is being directly sampled at 44k1, then you're going to need a brick wall filter on the input of that too (or you can oversample with a high rate ADC and do the brick wall digitally). If the source material is cut off hard due to the sample rate, no amount of oversampling can fix that. For robustness sak…

Agreed, which is why I don't think anyone argues against, say, 192kHz/24bit on the production side. Unfortunately, I think that people look at what the studios use and interpret that as a quality signifier when it really has no use once the signal is mixed down for transmission.

What I'm getting at though, is that if the source material goes from 192/24 in the studio and then downsampled to 44.1/16 into the final file that gets distributed, that material is going to have a brick wall filter applied to it in the downsampling process. If new systems like this are actually distributing real 192/24 streams that haven't ever been downsampled to 44.1/16, I'd expect to get better results from it than from 44.1/16 oversampled back up to 176.4/16.

I'm not saying that we can hear stuff on the recording at 30kHz, but the stuff right at the edge of our hearing around 20kHz will get less messed up.

My gut feeling is that it's way easier to make a well-engineered audio system when there aren't any sample frequencies that cause any of the stopbands to be close to audible frequencies.

Re: The Pono Player and Promises Fulfilled

#36

Post by gwern »

SloopJon wrote: post #30
gwern wrote: post #14

Earlier quoted context omitted.

> "Usually it would take me 5-15 minutes of listening and slowly switching back and forth between sources before I could determine which was the Pono Player." Yes, I'm not clear on how his blinding setup works, but this sounds like the sort of activity that could easily unblind oneself.

> I'm not clear on how his blinding setup works Search for "Blind Testing" on the first page: "I use a passive three-way switch to route the outputs from the three sources to a pair of headphones. ... without looking, I scramble the cables in each hand."

Can that possibly work? I would not expect cables to be perfectly indistinguishable (human touch is pretty sensitive), if only because of slight differences in tension/position/direction.

Re: The Pono Player and Promises Fulfilled

#37

Post by stolio »

badsock wrote: post #23
stolio wrote: post #18

I almost get a kick out of the cries of "science" debunking the Pono player. Yes, a 192k playback sampling rate is a joke and maybe even superstitious. There's not much of a reason for anything to play back at over 96k and many argue 41k is sufficient for mixed/mastered material. Point granted. However good engineering is most definitely not a joke. Using higher quality DAC's (digital-to-analog converters) and better…

The thing is, we've long past the point where it's a difficult task to exceed the the perceptual limits of the human ear. Even the middle-of-the-road DACs are indistinguishable from perfection now, and the rest of the circuit is just ensuring that any noise in the power supply and the output traces are below a certain threshold - not trivial, but the industry has built techniques and for doing this in much, much more…

Isn't this the middlebrow dismissal we're supposed to avoid here? I'm not sure where the ubiquitous, portable, high-quality music players are that make Pono redundant. Are you referring to smartphones?

If you look at actual studies of the performance of smartphone audio you see it's not a trivial task to get right[0], if we're seeing problems on a large company's flagship model like Samsung's Galaxy S5 then this isn't a solved problem.

Playback at home while plugged into a 120V power grid with equipment that only needs to fit into a shoebox is a bit different from playback from a device that's simultaneously a computer and a phone which also happens to have severe space and power constraints (and a giant color touch-screen to boot.)

[0] - http://www.anandtech.com/show/8078/smartphone-audio-testing-...

Re: The Pono Player and Promises Fulfilled

#38

Post by badsock »

tonyarkles wrote: post #35
badsock wrote: post #33

Earlier quoted context omitted.

Agreed, which is why I don't think anyone argues against, say, 192kHz/24bit on the production side. Unfortunately, I think that people look at what the studios use and interpret that as a quality signifier when it really has no use once the signal is mixed down for transmission.

What I'm getting at though, is that if the source material goes from 192/24 in the studio and then downsampled to 44.1/16 into the final file that gets distributed, that material is going to have a brick wall filter applied to it in the downsampling process. If new systems like this are actually distributing real 192/24 streams that haven't ever been downsampled to 44.1/16, I'd expect to get better results from it th…

Ah, I get what you're saying now. On the downsampling side, correct me if I'm wrong, but my understanding is that resampling in general is a well-solved problem (brick wall included), given reasonable target rates.

In terms of it being easier to filter an orginal signal than to filter a downsampled->upsampled one... my gut goes the other way, but it's something I'd definitely have to look into before I'd comment either way. Interesting question though.

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