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Comment by AdrianB1 | Hacker News Reader

You don't understand the power of naivety, placebo effect, dreams and stupidity composed (multiply all). Not in any way intended to insult these people, I know a few (not as rich) and they simply do not want to understand the basic principles behind digital signals, error corrections etc. I know people that work in IT and still pretend that audio transmission over USB can add jitter to music and that a DAC can "open" or "close" "the stage" by low quality processing of the signal. There is no way to convince these people they are wrong, so I stopped trying many years ago.

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I know people that work in IT and still pretend that audio transmission over USB can add jitter to music and that a DAC can "open" or "close" "the stage" by low quality processing of the signal.

Audio transmission over USB with cheap converters and poorly chosen levels can result in loss of sound quality. I'm pretty sure you can tell the difference between 8 bit, 12 bit, and 16 bit sound. Choosing levels poorly can reduce your resolution.

Also, there are cheap analog to digital converters which use voltage comparison, which basically linearly "search" for the voltage they should be encoding. So those fundamentally do introduce jitter. (Large changes in signal voltage get encoded a bit later than small ones.) I'm sure there are ways that jitter can be introduced the other way around by cheap DACs. However, if you add more bits and increase the sampling speed, those should largely go away.

Devices like DACs also include a small amplifier, and if those aren't properly designed, there can be some distortion introduced there as well.

That said, there are times when people think they hear a difference, and it's woo. There are other times when the difference is real, however. Audio is a real field with some real science and know how behind it. Please don't grant yourself instant superior expertise just because you've read some stuff online.

(On more than one occasion, I've gotten the "all audio is woo" knee-jerk from programmers who were just reacting to hearing the words "frequency response" not knowing what it was, but labeling it as woo. Ironically, they did remember stuff about Fourier transforms. Go figure.)

It's almost as if there's a middle ground to be had somewhere.

There are definitely things which can perceptually detract from audio which people just don't think about.

I'm about to buy a couple power conditioners for my electronics because the wiring in my new apartment is garbage and every little spike in voltage comes through as a loud pop in my speakers and headphones.

But more subtly, my audio is constantly being degraded because I have a few cheap dimmers which cause a constant interference pattern in my electrical circuit that weren't a problem in my last apartments, and I can even hear fluctuations caused by my refrigerator if I listen closely.

And all of these things which can subtly degrade audio are 100x more of an issue when you're recording audio. Run any given song through a spectrogram analyzer and you'll usually see a horizontal line or two which could be anything from a little cable noise to a CRT screen.

Wow, that is pretty bad wiring. I can hear an audible hum from my subwoofer when my wife runs the vacuum or blow dryer but that’s about it. And those are about the highest pulling appliances you could have in a household and the sub is pretty big with pretty powerful amp.

Brushed AC motors degrade power quality, although they're normally equipped with filters.

Right, similarly to my dimmers that constant gating of power draw as the brushes make and break contact just wreck your AC circuit.

Bad wiring and a sub-par setup will make that bleed right through your speakers.

Not sure why you got downvoted, I've seen crappy electricity in my own home office after I got a UPS for my computer system. It would have its fans kick in regularly to modulate the voltage that came in at a crazy high ~255v (Australia).

I got the APC Line-R 1200VA Line Conditioner With AVR installed in front of the UPS and couldn't be happier now - it steps down the voltage and gives the UPS peace of mind.

Try the APC, not the most expensive thing but it's worked well for me.

Installing a UPS behind the conditioner sounds like a good idea. I have been meaning to get one of those... Thanks for the rec on the APC, I bookmarked it for comparison later. What UPS are you using?

I am using the CyberPower Value GP LCD 1500VA/900W Line Interactive UPS, but it looks like it's been updated to be named "SOHO" now:

https://www.scorptec.com.au/product/UPS/UPS/44933-VALUE1500E...

I also have one of their smaller BRICs for my HTPC / home NAS JBOD server: https://www.scorptec.com.au/product/UPS/UPS/40279-BR850ELCD

The voltage in that part of the house appears to be better, but the circuit is easily tripped when running toaster + micro or similar, so having these UPSes has taken a lot of frustration away.

Actually just checked my invoice and I got them both in 2012, which is a little while ago now, and they're still good with their original batteries.

Regarding your usage of 'cheap', I would read this as the difference between a 50c or $5 component. I can understand spending more to get a reputable brand compared to buying the cheapest no name item from AliExpress.

However audiophiles are a whole different level. People spend tens of thousands of dollars on items that have questionable difference in quality. I guess people do the same with cars though, a Toyota Corolla will get you to work just as well as a Rolls Royce Phantom.

Wine might be a better comparison (at least a Rolls and a Toyota look different). Many could tell the difference pretty well between a $5 and $20 bottle (hint: the $20 one is the one not loaded with sugar), but not a whole lot of people can tell the difference between a $20 bottle and a $200 bottle. The law of diminishing returns kicks in pretty quick with both wine and audio. I think with audio once you’re in over a few hundred bucks for your set that wall comes up pretty quickly.

You got it. There are degrees here. You can be an "audiophile" and not break the bank.

> difference pretty well between a $5 and $20 bottle (hint: the $20 one is the one not loaded with sugar)

Wine loaded with sugar??? AFAIK, in a dry wine all the sugar is converted to alcohol- even in the case it's been added before the fermentation, which is still pretty rare, at least in major wine producing countries. That is definitely not the difference between a $5 and $20 bottle of wine (in Italy you can still get excellent wine for $5 a bottle if you buy it from the producer, btw).

whether it's rare depends on the wine. most champagne has added sugar before fermentation.

search for "brut nature" which for cava, champagne and the like means it's only the sugar in the grapes themselves.

If it's added before fermentation, it's still not in the final product, as it's been converted to alcohol. But you're right, champagne, even the best brands, has some sugar added after the fermentation, about 12g/l. It's part of the method. It's still a rather tiny amount if you consider that an orange juice without added sugar has about 90g/l (and you do drink it by the litre, as opposed to champagne...)

This is incorrect, there is always "Residual Sugar" [0] in wine, even when it's dry. Of course, GP is also not correct as there are plenty of wines with high RS that are very expensive while I can get a 7g/L RS wine for around 4€ here.

[0]: https://en.wikipedia.org/wiki/Sweetness_of_wine#Residual_sug...

It also depends on the wine... The difference between a typical $10 bottle of pinot noir and a better $30 bottle is like night and day... But most varieties aren't as delicate and hard to make, so the differences get way more subtle.

Yeah, and sometimes one car is better than another car, even if they have the same engine ($5 wolfson DAC), because more love is given to everything around the engine.

If you just want to put together a cheap car with a good engine, that's a different thing from wanting to build a comfortable or speedy car with a good engine. Someone who isn't in the market for that extra level will just be a sceptic and say "this Audi is just a volkswagen with a prettier body", but if you sit in one you'll feel the difference. (not sure if Audi's have VW engines)

"More love" in this case doesn't have to mean more than maybe a retail price of $50 or so, to get a DAC with a frequency response so flat and a noise level so low that any difference to more expensive items is purely academic.

Digital to analog conversion is a solved problem, with inexpensive commodity parts. Even if you buy an expensive DAC, the studio gear used to produce the music you listen to has gone through dozens of A->D->A conversions, all done using standard commodity parts. No one builds fancy audiophile-approved DACs and ADCs into mixer or studio gear.

In my home setup, I'm using a DBX DriveRack PX as a DSP EQ and crossover between my main monitors and subs. It's almost a decade old, but its signal/noise ratio is on par with the newest gear you can buy. Any competently built pro gear from the last ~10-15 years with 24-bit conversion can be plugged right into any analog signal chain and be 100% audibly transparent.

People worry way too much about the electronics, and way too little about their speakers and rooms.

You think they're overpriced, but I bet you no one is getting (very) rich off these $400 DACs. Even more, I think many of them profit so little every once in a while a company pivots or goes out of business.

An Audi also has just a couple thousand of extra love worth of physical cost added to it, but the retail price is easily upwards of $20.000 above the equivalent VW car. That's because if you sell fewer units, the r&d and marketing costs per unit are much higher, as well as the required profit per car sold.

If you get a good deal on your hardware, you might have that good DAC in a nice box with a pretty manual for $50 physical costs, then put it on a prime shelf in a nice Hi-Fi store for $130 (30% of $400), maybe $50 to target and prime your customer, and then use $150 to pay your audio engineer, your CEO, maybe outsource the rest of the company infrastructure, and then 8% interest to your lenders. That's 1.7M profit at 10.000 units sold (assuming that you do all of this within a year).

I have no idea if 10.000 units is close to reasonable for an indie hardware startup, but calculations become a little more complex if we're going to have to take a multi year ramp up in account..

edit: Sorry I got caught up a little in the startup aspect of it. Your system sounds great, but your DAC (and DSP+crossover system) also cost $400, so you're not making a point?

No one is getting rich off DACs, except for the makers of outrageously overpriced 4- or even 5-figure retail price units. After all, DACs are commodity hardware, boutique devices serve primarily serve as audio jewelry, with no technical benefit.

The DAC I use cost less than $30, yet performs well beyond the limits of human hearing. The DriveRack did have an MSRP around $300 when it was new, but usually $200 on sale, but it does do a whole lot more than a DAC, and the base price level for pro gear is somewhat higher than for consumer gear.

As I said, people focus way too much on electronics, when even basic devices are more than good enough. I don't even have to use the DAC anymore, after I switched to DisplayPort for my monitor, which has a perfectly good analog stereo output. The only reason I keep the Toslink DAC hooked up is pure laziness.

Good DACs and ADCs are useful for recording studios who have a lot of analog outboard gear (where the signal leaves and enters their digital setup multiple times). But for normal listening where there are only one or a few conversions, the point of diminishing returns is pretty low.

Most of the perceived gains in quality of higher end equipment (DACs, Amps etc.) come from the higher voltage of the outputs (where you connect your speakers and headphones), this translates into an increased loudness/volume level.

So if you want to do blind tests between different kind of equipment, you have to measure that voltage and make sure it's equal across different pieces of equipment (you can adjust in realtime by volume knobs), otherwise the louder one will always win and perceived as higher quality.

I have a decent hi-fi audio system at home, and there is a clearly audible difference between playing from my high-end CD player, and playing FLAC from the audio out of my Macbook.

The difference is not one of loudness but of 'energy'. A snare hit played from the high-end cd player sounds like someone actually hitting a snare; you can feel there's actual energy in the hit, while the macbook out sounds flat, even at higher loudness.

I'm not sure what is the exact cause but I've always guessed that it comes from the qualities of the built-in amps in the DACs.

> The difference is not one of loudness but of 'energy'

Aren't those the same? Put more joules into the speaker wire and more joules of sound pressure waves will come out of the speaker cone, which just means the sound will be louder (until you reach the mechanical limits of the speaker, of course, but no DAC in the world could possibly change those).

>Aren't those the same?

Not really. If you take some of the transients out of recorded drums they will sound lifeless, without "energy", but not necessarily quieter.

That sounds like amp presets to drop bass, which would make perfect sense on an Amp expected to be used on laptop speakers.

I think the general problem is mid-range speakers and reasonable settings is all it really takes to have quality sound, but people want to be above average and therefore look for ways to discriminate between better sound and worse sound differences they can't "yet" hear. From there you get into placebo and random correlations.

It can be the case that the output of your Macbook isn't really flat, or that you have some kind of software processing enabled. You could test a $20 class compliant Behringer UCA202 USB interface against it, which is flat, and try to disable processing or use a software which just passes the signal to the interface.

It can also be your room. If you're not exactly located in the same listening position the listening experience can change a lot, even with the same setup.

Your room is basically an equalizer and should be regarded as a part of your audio system. That's how some Hifi sellers can trick you into more expensive setups, they just change the speaker positions or your location to optimized defaults. It's crazy how they can trick people.

A harder hitting snare can be caused by changes to the upper mids and lower highs, by anything that is located between you and the speakers, and then the later reflections of the room which also add up.

Consider audio benchmarking.

For Widows there is Rightmark, maybe you could run the Macbook's output against a decent Windows DAW.

audio.rightmark.org

Another possibility is that your CD player might not be flat. Marantz, Yamaha and other manufacturers add their slight sound signatures to their higher and models.

I never benchmarked my Yamaha CD-S300 to other devices, but its flyers and web site never says it's completely flat on the analog outputs. The reviews of the player notes that it has the distinct Yamaha signature too.

Also "Monitor" and "Flat" devices as their name implies sounds pretty flat and dull.

All-in-all you should consider taking response graphs of your devices rightmark.

> Also, there are cheap analog to digital converters which use voltage comparison, which basically linearly "search" for the voltage they should be encoding.

Integration type ADCs are not necessarily cheap. And you always put a sample-and-hold circuit in front of integration type ADCs, which completely eliminates the sampling time variance.

Also many people are unaware that the Nyquist theorem states, that the _average_ sampling frequency must be at least twice the highest signal frequency. The sampling points may indeed jitter around a little bit, as long as the jitter is distributed evenly. As a matter of fact, adding a little bit of sample jitter can be used as a poor man's dithering, to shift the LSB noise spectrum above the reconstruction filter cutoff frequency.

Jitter is mostly a problem with sample clock distribution. Too much jitter and the sample clock no longer arrives with the right delay with respect to the data, which may create large transients, e.g. whenever the numeric value rolls over some power of 2 (a lot of bits change); this problem could be avoided using Gray codes, though.

Oh, and then there's Sigma-Delta Modulation.

> a DAC can "open" or "close" "the stage" by low quality processing of the signal

In principle a low enough quality DAC certainly could affect "the stage", but in reality even cheap ones are likely good enough.

> There is no way to convince these people they are wrong

I'm pretty sure many of them don't want to be convinced since it would make their hobby pretty boring. I also wouldn't be surprised if industry players actively spread myths like these to sell more (expensive) products.

No, cheap DACs are not “good enough” unless you’re completely indifferent to audio quality.

There’s certainly woo and outright fraud in audio. But there’s also attention to detail.

Professional studio engineers will spend $3000 on a high-precision digital clock for their DACs because it makes a clearly audible difference.

Software people don’t understand that human hearing, and human sensitivity to timbre and distortion, is spectacularly non-linear.

Hearing isn’t a linear counting device with x volume levels. It’s an incredibly sophisticated neural network that performs real time classification and source separation based on spatial and ambient cues, spectral analysis, predictive modelling, and entropy estimation.

Some people’s brains and ears are better at all of this than others. Those people can hear things other people can’t.

In music, someone with a trained ear can name the notes in a chord. Someone with exceptional skill can name the notes in a random cluster of pitches on the lowest octave of a piano.

Audio quality has analogous levels of sensitivity. People who have neither shouldn’t be telling people who do what they can and can’t perceive.

Can you elaborate more about $3000 digital clock for DAC?

> Professional studio engineers will spend $3000 on a high-precision digital clock for their DACs because it makes a clearly audible difference.

I don't know what kind of frequency stability you really need (please enlighten me), but I checked on one of the components retailer websites, and found that even the most stable MEMS oscillators are only a few bucks a piece, any DAC or ADC manufacturer that claims that's worth a $3000 markup is running a scam.

> Software people don’t understand that human hearing, and human sensitivity to timbre and distortion, is spectacularly non-linear. Hearing isn’t a linear counting device with x volume levels.

As a "software person" I take exception to this. Who exactly of my colleagues claimed that it was? Not even the cheapest, most terribly sounding, incompetently designed child's toy's "what sound do cows make" 8-bit 8kHz DAC produces output with x discrete volume levels, it produces a continuous signal. A bad sounding signal perhaps, but a continuous one nonetheless. Plenty of software people know this, but do audiophiles?

The main kind of clock you can spend $3000 on is an atomic clock (usually a rubidium frequency reference). There's absolutely no point in this for an audio system, but it's a quite trendy money sink (especially because atomic clocks are if anything worse than a good crystal over short time periods and only dominant over very long time periods: if you need both you can combine them).

> People who have neither shouldn’t be telling people who do what they can and can’t perceive.

Even if every properly conducted blind placebo test seems to indicate otherwise?

Or even if it makes no physical sense so it even seems worth doing a test. It is depressing to be told people shouldn't do science, especially for the benefit of consumers.

"Some people’s brains and ears are better at all of this than others. Those people can hear things other people can’t."

Well, a lot of this Audiophile stuff is voodoo but if it makes them happy, who cares. But I am skeptical about your statement. The easiest way is to always do a blind or double blind study. A German computer magazine did this once with CD vs. mp3:

https://www.heise.de/ct/artikel/Kreuzverhoertest-287592.html

The guy who was best in spotting the difference and assign it correctly had an ear damage. Since mp3 was developed for "healthy" ears this is not too surprising.

"People who have neither shouldn’t be telling people who do what they can and can’t perceive. "

Let's agree on the scientific method. Anything that shows a significant difference in a double blind study, even for a specific individual I accept.

By the way, I hear my music on my computer via mp3 and send it into my super old tube amplifier. :-)

>Professional studio engineers will spend $3000 on a high-precision digital clock for their DACs because it makes a clearly audible difference.

No, this is pure steaming BS. $0.2 crystal has 50 ppm stability.

>Some people’s brains and ears are better at all of this than others.

Better than radio receivers operating at GHz ranges I guess.

What kind of arguments you've been using? Are you talking specifically about the DA chips or the black boxes containing them? I pretty much can agree with you regarding the digital side of things, but could the actual appliances have notable differences in their analogue side or configuration? Maybe the actual value of having a $400 DAC appliance (built around a $2 Wolfson DAC chip) is going around problems in a computer's noisy or badly pre-amplified integrated audio output.

I don't mean to question your expertise on the subject, I'm just after an explanation what are the exact reasons why the setups with separate DAC and amp boxes have made me find new musical instruments on my audio files. And of course it would be nice to know if there is an inexpensive way of getting the analogue signal to a good amplifier without somehow ruining it.

Spend a lot of money on object —> Expect difference that doesn't exist —> Listen for this difference —> Careful listening reveals previously unnoticed nuance —> Revelation is attributed to new object.

Rinse, repeat.

to an extent, it's often part of the ~value of new devices too. your new computer seems so much better when most people have zero idea if it is or where it is.

I fully agree that an external USB DAC can have a much better output quality than the motherboard output that can be influenced by interference; I have an external DAC myself, but I bought it for about $50 (list price was $200 in a hi-fi store, I ordered it from a small reseller). Not talking about the $400 box with $5 parts in it, but about common sense (plus some physics and math) in understanding what a DAC does and does not. Not an audiophile myself (well, not that kind of audiophile, but with some passion for the music), I cannot provide good and trusty advice to others, but a digital-out (very common) to an amplifier with a digital-in (very common) is a very simple and cheap way to do it; I am not aware of a cheap way to get very good quality analogue signal out of a PC, for example, as add-on sound cards are very rare these days and very good audio on motherboard is fairly restrictive, but the digital path is wide open. Coax or optical out is the cheapest, a DAC is the next, but the difference between a $50 DAC and a $500 DAC is negligible.

I do agree. I think it has to do with the fact that most motherboards have pretty terrible analog audio support. Every motherboard I've ever had has sounded meh compared to a cheap USB DAC.

It would be super interesting to compare an iPhone analog vs iPhone with a DAC.

I guess you'd have to use an old iPhone with an audio jack though :(

Even the motherboards have gotten better over time. I recall being over at a friend's house in the early 2000's and he was saying, "my speakers are so bad, I guess I need new ones" and I said, "wait, try plugging those into a different source", which we had in the form of another friend's laptop. The audio immediately went from tin can quality to reasonably transparent. The issue was with the cheap DAC in his computer.

But I usually go with onboard sound these days. I did get a FiiO E10K when I got new headphones recently, but I've put it away even though the sound is noticably smoother and less compressed-sounding than my onboard sound - it's another cable and associated hassle.

The reason to go for pricier stuff in my mind is to get more I/O. Good audio interfaces for recording can run you hundreds, and you're paying there mostly for having more channels and some recording features. There's more of an expectation of getting what you paid for.

The biggest problem with onboard audio generally isn’t the DAC but the amp, especially with higher end headphones.

I don't disagree with the point you're trying to make, but I'm not sure if USB is the best example to make that point.

Case in point: when I used a USB DAC with my NUC there's an intermittent electrical noise that's actually quite audible and distracting (even when nothing is playing). I ended up switching to another cheap DAC that accepts optical input, and the noise completely disappeared. I'm not entirely sure what caused the electrical noise to begin with, but that it existed means there's some potential for USB to mess with the audio signal.

It could be a ground loop hum, not USB's fault really, but you do get electrical isolation with toslink.

Can confirm. Using my SPL Crimson audio interface with a cheap USB hub leads to clearly noticeable noise and distortion (particularly when silent). Connecting the interface directly to the Mac Mini removes the issue.

Power audiophiles don't do digital. Noise is a very real thing in analog. Go to any rehearsal studio and ask about the power conditioning: almost sure they're not using power as coming from the steet.

To me, my iPod Shuffles, launch day iPhone, and modern iPhone all sound very different from one another when I play the same song. (I prefer the Shuffles.)

Is this a real thing, or should I upgrade to a better brand of crack?

Could you have a couple friends help you set up some double blind comparisons? I'd be interested if learning the results.

Forgot to mention in my other response... the volume is the biggest influence in perceived sound quality. Equalising that in such devices can be tricky in an impromptu setup.

Then maybe you don't need to equalize it? Run your experiment with both sources at a wide range of volumes. If there's actually a noticeable difference, it should come across in the data.

Probably mostly the latter. The headphone adapter with recent iPhones measures remarkably well for such a tiny device: https://www.head-fi.org/threads/what-is-the-sound-quality-of... (scroll down a little for lots of geeky measurements).

It's hard for our brain to comprehend that such a tiny gadget can sound so good, so I suspect that accounts for a lot of the perceived difference. Also, some music can sound better with a poorer output device by e.g. smearing noise in the treble or rolling off excessive bass.

I've always wondered if the headphone adapter contains a DAC or if it just acts as a breakout box for a DAC already in the phone. I found some people claiming it does, but none that I can see cite a source for it.

As far as I know, lightning connectors (as opposed to their 30 pin predecessors) carry no analog signals, so the DAC necessarily has to reside in the headphone adapter.

I also have a 6th generation iPod Nano, an iPhone 5 and an iPhone X. I can hear the difference between the Nano and the iPhone 5.

The difference is not much. iPhone has slightly better highs and slightly tighter lows. The headphones I'm using is Sennheiser MM70i (They use the same buds with CX400-II, I also have these).

I didn't found the difference with "critical listening". One night I just started listening it, and it sounded different to my iPhone. Then I played the same song on the iPhone and found out the difference.

The difference maybe due to different generations of DACs, different OPAMPS, different power budget, different decoders, etc. As I said before, the difference is not that much, but normal for the evolution of these types of electronics. Nano honestly sounds impressive for a device that compact.

P.S.: I used to play euphonium in a large band and double bass in a symphony orchestra, so I have trained my ears for separation and tracking of instruments and rhythm. This is why I'm a bit more sensitive to these things than most of the people around.

Power, DAC'S and headphones are pretty much all that matter when it comes to sound quality. Power matters the most. "You don't understand the power of naivety, placebo effect, dreams and stupidity composed (multiply all)." Its not that simple.

If you use speakers add amplifiers, speakers and (most important) acoustics

>You don't understand the power of naivety, placebo effect, dreams and stupidity composed (multiply all). Not in any way intended to insult these people, I know a few (not as rich) and they simply do not want to understand the basic principles behind digital signals, error corrections etc.

You also don't understand that these people have found a pastime that makes them happy and engaged. Who cares about the actual difference in sound compared to that?

Whatever your basic statement was, it's proven valid. Tremendous how much you can discuss it in such a wide small area. AD, wine, Jitter ...

:-)

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