Power cord blind test

[digicidal]

Shine your flashlight inside your amplifier and look at the size of the wires at you first solder point, then look at the size of the wire wrappings on your transformer... I’ll keep sipping my beer and wait for you to get back to me...

Well sure... but it has all that magic smoke inside (unless it already escaped that is)... so it's not a fair comparison.

I will say the one thing jewelry cables have going for them is that they're available in custom lengths... not worth what they charge, but it would make organization a little easier in some cases than just having 1m & 2m lengths.

 

[g29]

I wonder what power cable this guy uses with his personal transformer.

 

[Jim777]

I think I'm going to start selling audiophile breakers and breaker boxes, every connection counts

 

[Thomas savage]

I think I'm going to start selling audiophile breakers and breaker boxes, every connection counts

https://www.russandrews.com/upgraded-rcd-consumer-unit-metal-case/

Unfortunately not cryogenically treated lol

 

[Wombat]

I like the way he hooks up that fancy outlet to 50 cent construction back box and of course, ordinary drywall. Wonder why they don't sell the backbox and new drywall to go with it.

Thomas, a market for specialised drywall for listening rooms/studios.. Try lead impregnated, silverfoil backed, cryogenically treated, constrained layer damping. Hey some of it could actually work if installed knowingly.

 

[Theo]

They definitely sounded different to me. So I downloaded the video and extracted the track in my audio edior. Here is the outcome:
As you see in the Left channel on top, the level suddenly drops with "the other cable." But nothing like that happens in the other channel. So either through mistake or on purpose, there is a problem with the capture of one channel. No way a power cord impacts one channel this way.

I did the same. The guy is a cheat. We don't even know how the recording was done. Certainly not a room caption, there's no way the sound would be such as what we hear. I did the same as you, and there are real differences in the signal. I did the same with the other video with the NFC stuff, and there are differences too.
I did the null test and differences are in the range of 20-15 dB peak. There's no way such devices would do something like that. I also did a A-A difference as there is a repeat of the recording with the same set-up, and it's not null either, much lower though...
I suspect the guy has added some compression in one of the signals, or a filter ? in the middle...

 

[Hypnotoad]

I did the same. The guy is a cheat. We don't even know how the recording was done. Certainly not a room caption, there's no way the sound would be such as what we hear. I did the same as you, and there are real differences in the signal. I did the same with the other video with the NFC stuff, and there are differences too.

He seems to be mad keen on the expensive stuff, I wonder if he gets a kick back in some way from the manufacturers?

 

[digicidal]

He seems to be mad keen on the expensive stuff, I wonder if he gets a kick back in some way from the manufacturers?

I read a comment from @amirm on one of the other cables threads which would seem to confirm that likelihood. He indicated that in response to sales pressure to purchase exotic cables with gear he was buying - they were willing to discount the equipment by the price of the cables in order to add them to the sale - because the commissions were so much better. Hence, he got the exotic cable for free... but they still made more money.

If you are selling something for $5K that costs you $50 to produce... paying a 50% commission is nothing. If you can find a few people to proactively attribute fantastical results, even better - you maintain plausible deniability that way.

 

[solderdude]

What do you guys think about this? Any issues? Objections?

Thanks Theo (and Amir) for taking the time, the issues and objections are clear.
Rigged and not truly blind.
The motivation behind the creation of the video is clearly money driven, not truth finding.

The guy is a cheat. We don't even know how the recording was done. Certainly not a room caption, there's no way the sound would be such as what we hear. I did the same as you, and there are real differences in the signal. I did the same with the other video with the NFC stuff, and there are differences too.
I did the null test and differences are in the range of 20-15 dB peak. There's no way such devices would do something like that. I also did a A-A difference as there is a repeat of the recording with the same set-up, and it's not null either, much lower though...
I suspect the guy has added some compression in one of the signals, or a filter ? in the middle...

Besides that, the heard differences cannot possibly come from power cables.

 

[Dimitrov]

I posted on his Youtube video just for kicks regarding the channel imbalance. This was his response :

I will investigate later today but If I was messing with any balance controls anywhere it would make the cable sound worse - not clearer with better bass?? The opposite effect would happen. the sound would not get clearer its impossible I am sure you will agree.

 

[solderdude]

The only way I see the mains cables having an influence is when they are run in parallel and close proximity (ty-wrapped together or in a cable conduit) of not, or poorly, screened interlinks.
When one insists on using those (because they sound so good) then in that particular case you may prevent induced hum when using a screened mains cable. These don't have to cost a lot though.

It makes more sense, however, to separate mains and interlink wires and when they do need to cross should do so under a 90 degree angle.
Using decent interlinks will help here as well.

The spectrum plots shown show the 'nasty' character of that possible induced hum which isn't a neat 50Hz or 60Hz sinewave.
Change the tonal balance, details or amplitudes of the speaker output terminals .. nope....

 

[Shadrach]

The only way I see the mains cables having an influence is when they are run in parallel and close proximity (ty-wrapped together or in a cable conduit) of not, or poorly, screened interlinks.
When one insists on using those (because they sound so good) then in that particular case you may prevent induced hum when using a screened mains cable. These don't have to cost a lot though.

It makes more sense, however, to separate mains and interlink wires and when they do need to cross should do so under a 90 degree angle.
Using decent interlinks will help here as well.

The spectrum plots shown show the 'nasty' character of that possible induced hum which isn't a neat 50Hz or 60Hz sinewave.
Change the tonal balance, details or amplitudes of the speaker output terminals .. nope....

You're joking right?
The radial house wiring systems in the EU all run mains cable hopefully in a conduit, in parallel formation. None of these wires are screened.

 

[solderdude]

You're joking right?

Nope... are your (not or poorly screened) interlinks from DAC to amp for instance running in the same wall conduits ?

I am talking about the mains wires from say a DAC or amp or whatever device in a stereo system 'neatly ty-wrapped' together with non-screened interlinks directly behind the stereo system because it looks so nice and tidy.

This has nothing to do with house wiring at all.

When some unscreened motor wires or mains wires to and from machinery next to sensitive sensor wires and had to find out where sometimes a seemingly random malfunction comes from you'll appreciate properly screened mains wiring.

The screening might (in some specific cases) only be needed directly behind the audio equipment to say an extension cord.
In 99.99% of the situations normal unscreened run-of-the-mill generic mains cables will be problem free.

Also this won't change the sound.
It might only add some hum.

 

[Shadrach]

Nope... are your (not or poorly screened) interlinks from DAC to amp for instance running in the same wall conduits ?

I am talking about the mains wires from say a DAC or amp or whatever device in a stereo system 'neatly ty-wrapped' together with non-screened interlinks directly behind the stereo system because it looks so nice and tidy.

This has nothing to do with house wiring at all.

When some unscreened motor wires or mains wires to and from machinery next to sensitive sensor wires and had to find out where sometimes a seemingly random malfunction comes from you'll appreciate properly screened mains wiring.

The screening might (in some specific cases) only be needed directly behind the audio equipment to say an extension cord.
In 99.99% of the situations normal unscreened run-of-the-mill generic mains cables will be problem free.

Also this won't change the sound.
It might only add some hum.

Okay, I see what you're getting at now.
Cable tidiness isn't an issue here.
I had misunderstood your post. I thought you were suggesting that because of the Lornetz force mains cables in house wiring and in extension cords would produce hum.
It is I agree quite possible to induce hum in badly shielded interconnects if run parallel to power cords but as you write, this has no effect on the signal as such, it just adds mains induced hum on top.

 

[ahofer]

Alan Shaw also checked the audio levels and came to the same conclusion.

When I bought my Harbeths I had no idea Shaw was such a harsh critic of audio woo. It's been a delight to discover it. It always made me feel dirty to even contemplate buying things that were marketed with obvious snake oil. (but I still have in storage 2 VTL 225 deluxe amps and a Systemdek turntable to prove I did it, many years ago)

 

[Dimitrov]

I have been checking the original recordings and there is no imbalance at all - the great news I can make another A/B where you can hear the differences again - this one might need turning up a little louder as I will not correct the volume of the whole video before rendering just leave the files as is. Might take me a day or more to make it I am very busy

His latest reply.

 

[solderdude]

fortunately we have pauls software to compare the files.

he should 'shuffle' A and B and not give clues and in the comments should reveal what was cable A and what was B.

 

[diegooo1972]

The small difference we are supposed to hear it's completely destroyed by compression in youtube.
A different level on only one chanell may delete a sound mostly registered on that channel at low volume.
That really seems to be done with purpuse.
I don't trust in this comparison. He don't say the way it was recorded. Still smoke on the water full a snakes oil.
When they will start to talk about science I'll listen. I don't care about their impressions.
Smoke smoke e then smoke again and again.

 

[Speedskater]

Cryogenically treating any AC power component or part will void it's UL rating. Cryo is way colder than the storage temperature limit.

 

[Hypnotoad]

Probably been posted before but here's an albeit old ABX blind test by Home Theatre HiFi to see if participants could tell the difference between stock power cords and the much lauded $2500 Nordost Valhalla power cords.

The Absolute Sound Golden Ear Award Winner – Harry Pearson, Dec/Jan 2005
“the Valhalla signal leads [interconnects and speaker cables] were a towering achievement, but one that has now been eclipsed by the power leads. The arguments for using the Valhalla power cords are even more compelling. Listen and you will buy!” Roy Gregory, HiFi+, Issue 28

Mr Gregory might want to invest in some ear cleaner?

If you want the readers digest version test results:

"The total number of correct answers was 73 out of 149, which amounts to 49% accuracy. That is no more accurate than flipping a coin, and therefore, no statistically significant detection of power cable differences.'

https://hometheaterhifi.com/volume_11_4/feature-article-blind-test-power-cords-12-2004.html