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DAC for CD Player and Media Streamer (and Bluetooth media player).

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navin

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The RPi4 has 4 X USB ports. So yes, you can connect an external hard drive, or a flash drive, directly to the Pi. Alternatively, you can stream from your PC hard drive as well.

All of the DACs you mention have slightly different measurements (see the reviews on here). However, these measurements do not translate into differences in sound quality. Unless a DAC measurers really badly, or it's faulty, you won't hear differences.

Thanks. Let me investigate this RPi4 more deeply. My goal is to buy (or build) a media streamer/server/player than can both stream audio and video from the internet and play from a local hard drive. I have about 1000 Movies and 2500 CDs ripped to a hard drive and also subscribe to streaming services.

Are there some good ready-built RPi4 based media players/streamers/servers (or kits) available?

I googled a few links but don't know which ones are worth putting my money on.
Amazon.com: CanaKit Raspberry Pi 4 8GB Starter Kit - 8GB RAM: Computers & Accessories

(2) Building a Digital Music Player with I2S?! What is I2S! EB#45 - YouTube
 
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navin

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You're confusing "different" with "better".

If you compare 2 products that measure well (thereby indicating that there should be no audible differences), the only way to establish an objectively verifiable difference in sound is through double-blind testing. Without this, it is impossible to isolate the cause of the perceived difference. In other words, any differences in sound are far more likely to originate in cognitive bias rather than in the audio equipment used.

I agree. Which is why I put "better" in quotes since it is subjective. It's like the amount of salt you want in your food or the amount of sugar, you like in your tea.

On the flip side, there have been ABX tests with devices that measure pretty much the same (where there should be no audible difference) that have shown that an "educated" listener (by "educated" I mean some familiar with both the products being tested) is able to distinguish with a degree of regularity that is more than random. I am not referring to any snake oil stuff (I do not subscribe to the Peter Belt mindset).

In the "old days" have been part of a few such tests myself. The DIYer/Cheapskate in me always hopes the less expensive product wins a test (besides who doesn't like a David vs Goliath story) but even given this bias I have had to concede that in many cases while the price of the more expensive amplifier may not be justifiable, it did have more authority; or that the more expensive CD player (this was the day when Wolfson, BurrBrown, TI and Cirrus Logic DACs were considered to be the ones to compare) was more "musical"/ "organic" or less "digital".

Audio is both, objective because we like to be able to measure what we are hearing; and subjective because we all have our preferences (sometimes these may be subconscious).

When it comes to DACs, most people will say it is the implementation that matters most. At the same time, we hear whispers and opinions of AKM-chip based DACs being smoother (in general), and ESS-chip based DACs having a hotter, more extended high end. Without even getting into other DAC topologies, even chip-based DACs are "said" to sound more different, than their measurements would suggest.

Unfortunately, I now live in a country where access to outboard DACs is almost non-existant. We don't have any "high end" audio market. Otherwise, I would happily subject myself to ABX tests and report my experiences.

Which is why I am on this forum. I hope to live vicariously and learn from you guys!

"You can take the boy from audio, but you cant take the audio from the boy"
 
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navin

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Now, as to whether DACs that measure significantly differently (where one is in the 70-80 SINAD range (or the lowest quartile on the old ASR chart) sound different- again it is a test I would love to see performed.

But my real question is if the outputs from the DACs (as Amir tests ) show incredibly low noise and distortion added to the source signal, where might these perceptible differences exist? What are they? That's around the point people start throwing in "transients", "plankton", "time domain"- which I confess start to lose me.

Anyway, we have different views. I don't believe the different chip or different price logic in itself is proof of anything.

I don't think our views are much different. In the end, we all want the best possible audio (be it subjective or objective) for the cheapest possible price.

One aspect we can consider is that many of the "reputed" recording engineers and music conductors are past 50, some even past 70. Any ear specialist (ENT) would tell you that hearing slowly diminishes after 40, and by 50, 60 and 70 we all lose a lot of our "top end" (the pun on senility is intended). Yet these engineers and conductors are able to continue to function (oftentimes better than their younger counterparts) because the is something they are listening for that only comes with tons of exposure, experience and learning. Maybe there are some aspects of sound that we cannot as yet measure because we yet don't know enough. Science is an evolving discipline.

In the 80s, Bob Carver was part of a famous amplifier challenge. He pretty much succeeded in using this to market his M200, M400, M1.0t (the amplifier that was part of the test) and M4.0t power amplifiers and also almost embarrassing the publishers of Stereophile. Too bad, he couldn't nail that coffin. Most of us sitting on the sidelines wanted him to win convincingly.

I can understand (at least in theory) the time domain and transient nature of music (the understanding of plankton, however, I will leave to Sponge Bob Square Pants). I can understand (again in theory) how amplifier topology and build can affect damping factor, slew rate, etc. but beyond a certain threshold am unable to determine without an ABX test which amplifier will sound better (or if they will sound the same) just by seeing their specifications. I have heard amplifiers from companies like Conrad Johnson, Krell, Audio Research and while they all sound lovely, they all sound different too. Yet they measure pretty much the same. This is why I believe that we may need to resort to some degree of subjectivity to fine-tune our scientific findings.

Back to the subject of that RPi4 machine. I have very limited abilities when it comes to computer technology. If you guys can point me towards a good media player that can work as a media player/server/streamer or a nice kit that I can buy and build, I would be much obliged. I don't need to have an internal DAC (as shown in the videos below). A 2 box design is fine.

(2) Raspberry Pi 4 based music server - YouTube
(2) Tonik Audio - YouTube

Have a good weekend guys (and gals). Thank you for allowing me the space to debate this freely and without ridicule.
 
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