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HiFi snake oil or i...
 

HiFi snake oil or is it?

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What’s the actual digital source?

Amazon Music. I was using UHD tracks to compare 48bit/192kHz.

Indicate on the source and on the DAC.

I started this thread as a bit of fun, I was shocked at hearing an apparent difference between 2 bits of 50 cm wire.

There's no need to start insulting people.


 
Posted : 12/09/2024 5:57 pm
J-R and J-R reacted
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If you send your 0’s and 1’s from a compressed source , you need to decompress it.

Sure.  But that's nothing to do with the cable.  Lossy compression is a thing, but the fact remains that what is sent down a digital cable must be the same when it comes out the other end or it's unfit for purpose.

If you repeatedly send the same song do you  train’ the decompression to do it better.? That is theoretically possible- don’t Spotify vary quality on demand theyre experiencing?

Left to their own devices, streaming services will generally negotiate a reliable transmission rate.  A system is only as fast as its slowest component, even a regular old HDMI 1.0 cable will absolutely muller a TOSlink cable when it comes to throughput.  But would that cause issues with regular stereo audio?  I'd have to run some numbers but I'd have thought it highly unlikely, I've shoved uncompressed 5.1 PCM across an optical cable without issue.


 
Posted : 12/09/2024 5:58 pm
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Well, yes, Error Checking & Correction exists.  But the net result is the same, either the data is intact or it isn’t.  Reconstructing missing bits doesn’t change the outcome unless you’re having to use a lower bitrate to ensure a reliable connection.

Afaik that isn't quite true for audio.  Yes there will be a bit of error correction but if it can't be corrected then the player will interpolate between the two good points

https://www.soundonsound.com/sound-advice/all-about-digital-audio-part-3


 
Posted : 12/09/2024 6:02 pm
sanername and sanername reacted
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After a quick google,

A PCM stream is in the order of kbps; optical digital craps out at 125Mbps; boggo HDMI is 5Gbps; the latest 'ultra high speed' HDMI is 48Gbps.

Whatever your audio issues, it's nothing to do with digital interconnects unless it is broken.


 
Posted : 12/09/2024 6:05 pm
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For your testing you should use a local source, such as a CD, high bitrate MP3 or FLAC file already stored on your device.

You don't want internet streaming/bandwidth to potentially add more variables/complictations to your experiment.

And just use one song, or maybe 3 songs that are very different,  say one Classical music track, one dance/techno, and one rock/metal track, so you get a fuller picture.


 
Posted : 12/09/2024 6:05 pm
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There is no bandwidth issues, both the streamer and the DAC tell me exactly what bit rate is going into them.


 
Posted : 12/09/2024 6:08 pm
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But the net result is the same, either the data is intact or it isn’t.

Cougar, old chap.

You're talking about objective, measurable facts.

This isn't a place for facts, this is a land for wires that are "subjectively better" and cost the price of a car.

With coax digital interconnets it is hard to get the correct impedance at the plugs apparently – they should be BNC but aren’t. That can have some effect apparently if it is viewed as a transmission line

Reflections on a 500mm digital wire will almost certainly not have any effect on the data integrity. Not at audio type rates. Might be an issue with 4k video speeds, but 48 or 96kHz (or whatever the current woo worshippers want in their system) - not a problem.

But yes, coaxes should be terminated.

Whilst a competent designer might put some internal termination inside the receiving unit, this is the land of audio woo and my guess (and my guess is subjective, so do one, audiophiles) you're more likely to find an amethyst crystal embedded in the volume knob to absorb the bad vibes and negative karma.


 
Posted : 12/09/2024 6:10 pm
hightensionline, funkmasterp, silvine and 7 people reacted
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Snake oil is actually an excellent conductor. But remember it won't have as much value second hand, as it's sound will have been affected by being burnt-in on two different systems.

I say keep the cable if it's pretty. Think of the pleasure you could have tormenting friends by telling them it sounds better and asking if they can hear it too?


 
Posted : 12/09/2024 6:43 pm
funkmasterp, tall_martin, funkmasterp and 1 people reacted
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This isn’t a place for facts, this is a land for wires that are “subjectively better” and cost the price of a car.

:ROFL: emoji.

But remember it won’t have as much value second hand, as it’s sound will have been affected by being burnt-in on two different systems.

That can't be right, the cable on the previous page comes with an optional burn-in service (for a premium).


 
Posted : 12/09/2024 6:53 pm
benos, funkmasterp, funkmasterp and 1 people reacted
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Oh, dear god! They actually do. No emoji can adequately express my despair.


 
Posted : 12/09/2024 7:07 pm
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This isn’t a place for facts, this is a land for wires that are “subjectively better” and cost the price of a car.

I'm abusing that phrazing next I'm after a new ( unnecessary) guitar/ watch/ car/ bike/ Rapha item/ twinkly gadget ans have no actual need for it.

You've made my afternoon @mrmonkfinger


 
Posted : 12/09/2024 7:20 pm
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Similar but different...

My field is 230 / 400V electrics,  a colleague who looks after the IT side of things is currently doing his pieces that data cable runs in a newly finished building are too long. (10% less and it would be ok)

Being a sceptic, who has crunched on dozens of cat 5 connectors to cheap cabling to build a home network, i find out hard to believe that it matters (will Joe Schmo in the new building notice any difference when opening their word doc / tik tok video / etc).

Not saying it is not measurable, just not relevant in this case?

TLDR? Slippery (slithery) slope between audio and IT?

By the way fed up with slow Internet? Click [www.fishedin/sucker.com] to order an air purifier to speed up our home wifi.


 
Posted : 12/09/2024 9:02 pm
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@bigyellowmarin - The Cat 5 thing is real - all cables have a set of LRC characteristics; so we can use this to calculate the losses over a run of cable; for Cat 5 plugged into a normal port; it's somewhere around 100m - and as your guy points out; 10% at that range makes a big difference. And that's the thing about digital signalling; it works perfectly fine as the distance increases / the cable is poorer - until it suddenly stops. You might get a cable that just about works after error correction on the fringe; but chop a metre off and it works fine - add a metre on and it stops altogether.

But we're talking cables that are two orders of magnitude longer here; and probably providing data at 1Gbps rather than 2-300kbps; again orders of magnitude.

For those that don't already know; have a read about eye diagrams.  https://incompliancemag.com/eye-diagram-part1/


 
Posted : 12/09/2024 9:39 pm
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Afaik that isn’t quite true for audio.  Yes there will be a bit of error correction but if it can’t be corrected then the player will interpolate between the two good points

That article is an interesting read, but it's from over 25 years ago (and concludes what I've been saying all along, you won't hear a difference until it breaks).

"The first thing to appreciate is the sheer amount of data created every second by a stereo A‑D converter.
...
If you scale it up for a 48kHz converter with 24‑bit resolution, an hour's worth of recording would require just over 1Gb of storage. That is a lot of data to have to look after — and as yet we have not given any thought to adding error protection data or any auxiliary subcodes for copyright status or timing information."

1GB might have been a "sheer amount of data" in 1998, but if my maths is on point a cheap TOSlink cable could pull that in about 2 minutes, ie you could retransmit it 30 times in an an hour.  Over HDMI you could transfer it six times over in one second.  Today I can stream 4k video in real time over the Internet for gods' sake.

No way, no how is a digital interconnect cable costing four quid per centimetre making the blindest bit of difference on a modern system.  It's a physical impossibility.  If what's going in one end is what's coming out of the other then there is no "better" to be had.


 
Posted : 12/09/2024 10:05 pm
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Not saying it is not measurable, just not relevant in this case?

This is kinda similar but kinda different.

Ethernet "Cats" are standards.  Cat5e - along with other Categories - specify things like maximum length of individual cable run.  If you stay within those limits then it is guaranteed to work, assuming everything is in spec.

Cat5e specifies 100m (including any patch cables at either end), if you have a 110m run will it work?  Probably, if it's in an electrically quiet environment; or maybe not, perhaps it'll only run at 100Mbps rather than 1Gbps, or start dropping packets all over the floor.  It's difficult to say with any certainty.  How about 120m?  101m?  You're out of spec, you're on your own.

This is why I have a bee in my bonnet about Cat6.  The Cat6 standard is far more exacting than Cat5e.  If you're doing a home install using Cat6 you're almost certainly out of spec unless you're actually a network engineer.  What you're actually going to end up with is an install up to Cat5e standard only with awkward, expensive cable.  Which, y'know, is fine but rather pointless.

Coming back to AV: modern HDMI cables are certified.  If it's got the hologram (and it's not counterfeit) then a £5 Amazon Basics "Ultra High Speed" HDMI cable will perform exactly the same as a £500 one with the sheathing hand-rolled on the thighs of Filipino virgins.


 
Posted : 12/09/2024 10:29 pm
Akers and Akers reacted
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just keep the cable, you know you want to

Well I like nice things, don't care if I can't tell a difference in sound. It was basically a freebie, I'd definitely keep it. Same if a paid thousands on speakers no way would I use cheap wires, everything would be in a compatible price range. Why ? Just because.


 
Posted : 13/09/2024 12:39 am
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Just as easy to keep it and treat it like the free bag of haribo that wiggle used to send with an order, you’d be lucky to get £30 if you sell it as without full packaging and purchase receipt it could easily be an aliexpress knockoff


 
Posted : 13/09/2024 12:50 am
J-R and J-R reacted
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On your home hifi set up I doubt you could tell. This type is kit is usually paired with speakers and amps/etc that start in the 5 figures.


 
Posted : 13/09/2024 1:28 am
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Don't forget the wooden cable lifters!


 
Posted : 13/09/2024 6:57 am
funkmasterp, leffeboy, funkmasterp and 1 people reacted
 wbo
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Yes there will be a bit of error correction but if it can’t be corrected then the player will interpolate between the two good points

Ultimately all digital to analog reconstruction is interpolation, it's just how smooth an interpolation do you want to do? FWIW I have a bit of experience with the display, storage, handling of seismic data, which ultimately is sound data, and how that is stored, and redisplayed.  I can immediately think of a good few things that are going to have a subtle effect on that reconstruction, and the quality of digital cable isn't top. Ergo my loaded questions on how people like spotify handle the compression and decompression of data.

I'm not even sure if I'd trust blind testing - if you play a song once from a digital source once, then play it again with the same kit I don't think it would be exactly the same as something outside of your control will have changed


 
Posted : 13/09/2024 8:56 am
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There's no point argueing about what should or should not be happening - double blind test it - if you can reliably tell a difference then that's when you need to look for why there are differences, and if you can't then that's when you wonder abouot how powerful the various forms of expectation bias are.


 
Posted : 13/09/2024 11:09 am
multi21 and multi21 reacted
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I’m not even sure if I’d trust blind testing – if you play a song once from a digital source once, then play it again with the same kit I don’t think it would be exactly the same as something outside of your control will have changed

should really be double blind - unless you can find someone who is completely disinterested in what they are switching, or use some audible signal to indicate that it's changed.

And you need to do the tests multple times with random switches to prove that you can reliably identify the better cable, or not. Don't do things like open the windows/doors, drink a glass of water, blow your nose, etc in the middle of the test.


 
Posted : 13/09/2024 11:14 am
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Thanks stevehine, thanks cougar, really appreciate your replies.

Would i be correct to takeaway from this:

If the install meets all the parameters of the Category the result is pretty much guaranteed.  Start abusing them and all bets are off.

Abuse could result in reduced performance (1Gb/s to 100kb/s to... ),

but the effect of the abuse is not linear, at some point the last extra meter will change it from a 'far less than optimal but maybe 'serviceable'' to 'plain broken'.

In a professional environment, it all comes down to risk appetite.

Not the risk of it not working, but the risk that lazy Shaun blames his lack of output on his spreadsheet taking too long to save, and everyone at his tribunal looking at you to answer "is it correct that his connection did not meet recognised  international standards".


 
Posted : 13/09/2024 11:17 am
DrT and DrT reacted
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Dowotmate?


 
Posted : 13/09/2024 11:45 am
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BYM > That's broadly my understanding, yes.  I Am Not A Network Engineer.

As cable length increases, so does the likelihood of introducing problems.  Exactly what you'll see and when I wouldn't like to predict. Increased latency/lag, reduced speeds, retransmission, out-of-order or outright failure of packets... From the user's perspective it's going to be most noticeable if they're streaming video or using Voice over IP (people generally have a low tolerance to even minor degradation of VoIP; a couple of extra seconds in saving a document would probably go unnoticed, a couple of seconds break in the middle of a sentence on a Teams call will rapidly have people climbing the walls).

A cheap nasty cable which is in spec but only barely might well see issues before a more expensive cable which comfortably exceeds it.  Some people argue in favour of full copper rather than copper-coated aluminium, the jury's out here for me personally but if you are right on the edge of tolerance then it may make a difference I suppose?  If you're running long cable runs parallel to mains power cables or through a machine shop full of lathes then environment could become a complicating factor (though really you should be running STP - ie, shielded cable - here).  And so on.


 
Posted : 13/09/2024 1:46 pm
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Conduction's all in the surface layer Cougar.

Alu is almost as conductive anyway, IIRC.

Don’t forget the wooden cable lifters!

I knew using plastic cable lifters would come back to bite me.


 
Posted : 13/09/2024 4:17 pm
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Conduction’s all in the surface layer Cougar.

Aye, which is exactly why I said I'm unconvinced.


 
Posted : 13/09/2024 4:25 pm
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I can’t think of any other industry which routinely trots out such astonishingly abject bollocks and not only gets away with it but has a legion of fans who lap it up. 

Well, there's this thing called Religion... have you heard of it?

Is it time for this again?  https://www.enjoythemusic.com/hificritic/vol5_no3/listening_to_storage.htm

I genuinely cannot tell if that is satire or an actual thing.


 
Posted : 13/09/2024 4:31 pm
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I genuinely cannot tell if that is satire or an actual thing.

"The various storage drives were sited in another room, connected to a Cisco Linksys E4200 wireless gigabit router in the listening room via 25m of Belkin Cat 6 Ethernet cable".

25m of bog standard Belkin Cat6?


 
Posted : 13/09/2024 5:02 pm
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Connected to a Netgear GS108. If that doesn’t contribute to a dull and uninspiring sound, I don’t know what will.


 
Posted : 13/09/2024 5:38 pm
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Don't turn valuable listening time into some kind of shite science experiment, just pour yourself a whiskey and enjoy the free upgrade!

I do also find that the more whiskey I drink, the better my equipment gets. Can any of the boring engineers on here going on about whatever boring physics they remember from 6th form explain that?? How does the whiskey manage to affect the signal from amp to speakers? I don't know or care but perhaps it's quantum.


 
Posted : 13/09/2024 5:59 pm
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I genuinely cannot tell if that is satire or an actual thing.

That has to be satire otherwise nothing makes sense any more


 
Posted : 13/09/2024 5:59 pm
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No problem with the OP raising this.

This is my take on this particular situation.

Some where in the uk a file of the song i want to listen sat on a server. It’s probably 100s of miles away. When i listen to that song you send a signal and that server starts sending the song to you. The 1s and 0s come off the hard disc as electrical signals. These are then converted to flashing light and go into a fibre optic. At least every 30km the signal goes back to being electrical to be cleaned up and boosted. It will also be converted to electrical signals for rerouting. Terrifyingly all the songs 1s and Os are multiplexed (mixed up with) everyone else’s 1s amd 0s in each fibre. Eventually it gets to a green box in my road and is then converted to an electrical signal for the last time. It then goes into a 1950s pair of copper wires. This wire then goes down my road under ground then up a telegraph pole, across the road to a horrible leaky plastic box hanging off my gutter. It then comes in though the front door to another horrible plastic box. It’s then about 3m to the router. Now my mate knows about this stuff and says the industry standard is that with error correction I’m getting only 1 bit wrong in every million million bits (10^12). Now you might be able to interpret between missing bits in songs but not software. I can save have downloaded things like photoshop and and they work! So this bit I’m struggling with. Having made this incredible journey the bit where the digital signal gets lost and degraded and we have to start interpolating is the last 50 cm.

You can see why I’m sceptical


 
Posted : 13/09/2024 6:03 pm
hightensionline, funkmasterp, somafunk and 3 people reacted
 wbo
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Despite what your kit is telling you Amazon music might be a source of variation . They're sending you a compressed signal - do they guarantee a rate? I used to be able to tell the difference between good and bad days on Spotify,  but going to premium fixed that as you go from streamed ( variable quality) to a download


 
Posted : 13/09/2024 6:07 pm
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Well I think I've come to my own conclusion.

I bought a 3rd cable for £12.

So I have a £5 cable, which I originally ordered to replace the £200 snake oil cable, as I did not believe it would sound any different.

I still think I can hear a difference in the sound from the cheapest cable but I can't from the other two.

The £12 and £200 cable sound the same.

So there seems to be something going on with the cheap cable. It can go back to Amazon and I'll get my fiver back.

I'm still not 100% on any of this and do wonder on the placebo effect of it all?

I didn't mention in my OP, that it also came with a fancy 3rd party power supply, still retails at £300.

I replaced it with a £35 Audiolab one. the thing is, the stock one by all accounts, a very good quality unit and supplies both AC and DC for different parts of the DAC.

It makes no difference.

There is even a fancy, super chunky, £50 mains cable.

So I'll be punting the 3 on ebay, a value of £550 new.

Even if I can only get 40% of their new price, (on things in good condition it's normally 50-60% IME), it will greatly decrease my original outlay of £260 for the initial purchase.

I wonder if I have just missed falling down the seperate ring main, mains conditioners, cable lifters, rabbit hole?


 
Posted : 13/09/2024 6:36 pm
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Coming back to AV: modern HDMI cables are certified.  If it’s got the hologram (and it’s not counterfeit) then a £5 Amazon Basics “Ultra High Speed” HDMI cable will perform exactly the same as a £500 one with the sheathing hand-rolled on the thighs of Filipino virgins.

Not sure this is correct, or there's a lot of counterfeit cables out there. Had a lot of trial and error getting my Oculus Rift working reliably with USB and HDMI extension cables. Finding reliable DisplayPort cables for high refresh rate displays has been difficult too, even when they meet the spec on paper.

Still, those are issues of high bandwidth requirements and i'm sceptical that would be an issue with audio even with cheap cables.


 
Posted : 13/09/2024 6:37 pm
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Well, USB is a whole other dumpster fire of protocols, vaguely-met standards and cabling from AliExpress.  I've been tempted more than once to purge the entire drawerful and start again.

I've never had issues with DisplayPort but I've never really had a reason to push it to its limits.


 
Posted : 13/09/2024 7:12 pm
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Apparently 'Owner of a lonely heart' by Yes is the go to track to weed out snake oil upgrades.


 
Posted : 13/09/2024 7:41 pm
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because you need to give your ears chance to acclimatise

Brilliant!


 
Posted : 13/09/2024 8:13 pm
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I’ve never had issues with DisplayPort but I’ve never really had a reason to push it to its limits.

in a simmilar fasion to HDMI, you do need a certain standard of display port cable (and compatible hardware each end of the cable) if you want to see super high refresh rates and stuff like that.

For example I can't run my gaming monitor at 1440p/165hz with HDR unless I use a DP 1.4 or better cable.


 
Posted : 13/09/2024 8:33 pm
 pk13
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All of this ∆∆∆∆∆∆∆∆∆∆∆∆∆∆∆\

Is mosty why I sacked off working with audio snobs I've seen Harry potters spells make more sense than some of the HiFi geeked out equipment.

If you need better power supplies to stop interfering with the music enjoyment. You need to have a word with the amp/audio manufacturer as they have put rubbish shielding or non into the unit.

In the days of old people using L/R audio leads with terrible plastic ends and rub off gold paint then yes spending $$$$  made a difference.

High speed HD leads that are cert are more than good enough.

I genuinely did see a scart lead on a B&O TV that gave as good as  720p once hd into dvi connection if your old enough to remember those.

Oh and cat5e definitely falls off a cliff over 100mts for HD video transfer.

But if it makes you happy then fine I think old cars drive better than new ones and obviously that's just wrong


 
Posted : 14/09/2024 11:06 pm
robola, ossify, welshfarmer and 7 people reacted
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We spend a lot of time blinding our experiments, because placebo works.

@batfink the reason for having placebo is that it does not work. It does however make it possible to measure the variability of the ‘no treatment’ influences [edit- on the endpoint measure(s)] to which all participants are exposed to varying degrees. this is composed of many variables. This may be what you meant with the shorthand ‘placebo effect’. I expect it is what many folks mean. Well, until an RCT shows that their putative drug has limited effect in the study. Then they start believing that filler or vehicle has a mysterious and variable benefit.

My, harsh, conclusion when folks claim that ‘the placebo effect was strong in our study’ is not that, say, steroids as standard care were unusually efficacious or that the placebo was remarkably effective but just that the control arm did OK. If this is in line with past variability measures of standard care then the conclusion that the investigational product is not a drug is just that bit easier.

This editorial on placebo makes for fun reading. https://academic.oup.com/aje/article/190/1/2/5876955?login=false

As for the amazing digital coax cable. Hey, OP if it sounds better to you that sounds like a win. Keep it

As part of your comparison testing Why not compare it with your old cable but wrap £100 around your old one? Then do the blinded test with an impartial assistant. When you finish the test and tally the results hold the cables and see which one you prefer.

Your blinded test will come nowhere near the standards of a clinical, or even psychology, study but it might be enough to persuade you either way.


 
Posted : 15/09/2024 8:14 am
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Your blinded test will come nowhere near the standards of a clinical, or even psychology, study but it might be enough to persuade you either way.

Surely it doesn't need to as the only relevant effect is that on a particular person?


 
Posted : 15/09/2024 10:27 am
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If your amplifier is not especially well shielded then maybe it's picking up interference from the cable. Perhaps a better cable picks up and radiates less RFI. Dunno.


 
Posted : 15/09/2024 10:43 am
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Have you got your DAC on a concrete slab?

Not exactly practical in my case; it’s attached to the back of my phone using a MagSafe case. Which has me wondering, do the magnets in the case and the cut-down piece of case the DAC is attached to have any effect on the audio information going from the phone to the wired headphones?

Which are studio grade Røde ‘phones.
I’m being slightly facetious, but magnets do affect audio, as indeed they affect light, so the curious side of my mind does wonder if there might be some very slight interaction or interference caused by the magnetic field.


 
Posted : 17/09/2024 1:36 am
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