More 'Audiophile' bullsh*t

[TonyRPH]

Driller said:

stuff

Driller, I sent you a PM - I haven't received a copy so I'm not sure if the PM system is working...

[TonyRPH]

custodian said:

Le TVR said:

While the statement is correct in isolation, they have overlooked the fact that the vast majority of domestic electronics is powered by Switchmode Powersupplies (SMPS). These are great from the cost/weight/efficiency point of view but from an interference pov they are a nightmare that require very considerable common and differential mode filtering to avoid passing RFI back into the mains. Yes there are some that are not that bad but there are also a lot that are 'Chinese'....

SMPS can easily generate harmonics back into the mains supply, again some a not bad but there are others.

Get a line coupler and a spectrum analyser and have a look for yourselves.

The idea that RF above 100kHz stands no chance is unbelievably short sighted. An E-I transformer may be fairly good but a toriodal is much worse. Guess what most equipment uses. Then the capacitors have an effective frequency range of a few decades before they stop acting like a simple capacitance.

So yes, there may be a lot of oily, slithery waffle out there but there are also some valid products. The big problem is how to differentiate between them.

Good post. Seperating the snake oil from the good stuff is the key issue. Ears can help with that. The sort of blanket dogma we keep hearing from Globs and his cronies is not remotely helpful but I suppose has to be expected on here.

Le TVR's post was indeed a good post however...

Mainstream brands such as Panasonic / Samsung etc. have to achieve certification in order to be sold in this country (and of course many others).

Part of this certification requires meeting standards regarding RFI transmission* back into the mains supply - and is why you see many devices with built in mains filters.

These filters are not there to prevent ingress of interference from the mains, but to prevent interference exiting the PSU on to the mains.

Also, SMPS design has improved greatly over the past few years, and interference is less of a problem than it used to be (even without filters).

• this also covers airborne RFI transmission, and has done so for many years.

I have liberated many a good IEC socket with built in mains filter from computer PSUs.

[TonyRPH]

Driller said:

Le TVR said:

While the statement is correct in isolation, they have overlooked the fact that the vast majority of domestic electronics is powered by Switchmode Powersupplies (SMPS). These are great from the cost/weight/efficiency point of view but from an interference pov they are a nightmare that require very considerable common and differential mode filtering to avoid passing RFI back into the mains. Yes there are some that are not that bad but there are also a lot that are 'Chinese'....

I can't claim to be as knowledgeable as you guys when it gets down to the PCB and components but wouldn't any half decent hifi amp power supply have the necessary electronics to deal with this?

Not always, no.

I usually fit a filtered IEC socket to the HiFi projects I build, although I can't say I've noticed any difference to the sound.

What it does do however, is suppress any mains borne interference such as (very) minor spikes on the mains caused by noisy appliances (usually poorly suppressed fridges) switching on.

But as pointed out in a previous post, due to stiffer regulations such interference is comparatively rare with modern appliances.

[TonyRPH]

custodian said:

Not on that particular one, but already done it in double blind testing with Siltech cables and certain others, one in particular that made the system worse. You might try a very simple experiment to test one aspect (assuming you've got a half decent system that you listen to regularly). Get a large Ferrite ring and try with it placed on the mains cable and then without it. Just let us know if you can hear a difference.

It would be interesting to see what (if any) effect these ferrite rings have on the purity of the mains waveform.

For a cable to make a device sound worse (however inconceivable this seems) would suggest that it is significantly distorting the mains waveform (if that could actually happen as such low currents) and hence causing some kind of non linearity in the PSU of the equipment under audition.

I'm also interested to know which types of ferrite were used in these experiments.

[TonyRPH]

custodian said:

Oh yes it can!

As per others on this thread - I would love to know the science behind this (besides the suggestions (and mechanics of) of ferrite suppressors above).

Let us assume a level playing field - e.g. a good quality, relatively noiseless mains supply.

How could a mains lead possibly add more detail* to the sound?

I'm simply struggling to see how this can be, taking into account the dynamic range of music, the human ear and the kit playing back the music.

If there was *that* much noise on the mains supply, that it reduced the amount of audible detail (note: audible detail - not detail retrieved by the playback medium) then I suggest that any issues are more serious than just a noisy (mains) supply.

I also cannot believe that a mains lead will influence the level of detail retrieved from any playback medium, in case that's your next suggestion.

• I believe this is what you are claiming - do correct me if I'm wrong.

[TonyRPH]

I will address your points by multi quoting (yeah look at me!!!)

custodian said:

Tony, I don't claim any particular expertise in mains cables so my experience is largely practical. I certainly agree that on initial consideration, it is difficult to see 1 metre of fancy cable at the end of several hundred feet of bog standard cable having any effect.

Practical experience seems to show the following

1. Running the HiFi from a seperate 30 amp spur improves the overall sound quality.

This seems to be a popular one - however on a traditional UK ring main, I would have thought the supply would be just as good - although I do take on board the point that it is not shared by any other device.

custodian said:

2. Some of the mains cables I have tried seem to constrain the sound, Isotek being a good example

I have yet to notice any difference with either mains cables, filtered sockets, or even a UPS!

custodian said:

3. Many of the cables I tried didn't make a jot of difference

My exact experience!

custodian said:

4. A rats nest of overlapping or coiled cables was always negative.

I can agree with this - by default I have always maintained good separation between individual signal leads, speaker leads and mains leads.

custodian said:

5. Sometimes the routing of cables relative to the equipment made a surprisingly large difference.

Surely this ties in with point 4? I can't say I have ever noticed any difference moving a cable 2cm to the left / up / down etc..

custodian said:

6. Use of additional ferrite rings was usually negative, making sound constrained

Around signal or speaker cables, I would expect some minor change - but not around mains cables.

custodian said:

7 a small number of cables made a significant improvement to sound quality. These included Siltech, audience, Nordost and others. Improvement seen as improved space in the sound (maybe reduced mush levels)

I've not tried any of the above-mentioned brands so cannot comment.

custodian said:

8. Surprisingly, some simple mechanical damping of mains cables could make a difference

Again, this is one that escapes me. The science of it is simply inconceivable.

custodian said:

The observations were confirmed by several listeners, both anoraks and none anoraks!

How far any of this can be explained in terms of rf, emf or even mechanical pollution, I don't know.

I guess that depends on your individual locality - i.e. were the tests performed in close proximity to any kind of radio transmitter(s) etc.

I did once live within 'spitting distance' of a fairly powerful VHF and TV transmitter, and never noticed any stray pickup on any of my systems.

I did however once pickup a CB radio conversation via my turntable many years ago - but I suspect that was more likely a poorly calibrated aerial setup (causing RF 'splatter') than my particular system being prone to RF interference.

For a brief period, I was quite enthusiastic about CB radio, and had a standard 4w AM transmitter tweaked to produce around 6w - I used to operate this within close vicinity of my HiFi and never once experienced interference.

[TonyRPH]

anonymous said:

[redacted]

Assuming no valve gear (and no class A amps), probably not much more than 2 - 3 amps at idle then...?

[TonyRPH]

Le TVR said:

I would recommend that you look at the circulating currents in the PSU, especially the charge cycle waveforms under transients. You are creating an inductive supply to a transformer. Note also that the effect of an inductive supply will be different for a PSU in a class A amp to a class B one as the mean-peak ratio is totally different.

This is also part of the problem with EMI filtering particularly differential mode.

If I understand correctly, a fancy mains cable won't have any effect on this though?

The current flow in a mains cable feeding a single load will be the same in both cores, resulting in opposite magnetic fields which will virtually cancel.

So the magnetic flux should be minimal (negligible at the low currents we're talking about I would have thought) so placing ferrite / moving the cable / placing the cable in close proximity to another cable will have no effect IMHO.

• in all honesty, I'm bordering on the edge of my knowledge here, so the above could be absolute codswallop.

[TonyRPH]

kayc said:

Personally i think you are incorrect..all cables affect the sound of a system from mains/interconnect to speaker...where people do talk rubbish is that they expect a cable to improve a system..it can never do that..what it can do is reduce the failings of a poor cable..no cable would be the ideal solution.

So, what you're saying is, that if I remove the traditional mains cable from my amp, and hardwire it with 2 core + earth mains cable as is run in the wall from the distribution board, this is better than using a 'standard' mains cable?

Obviously, no cable is impossible, unless the equipment is powered by batteries.

But this opens up a whole new can of worms, wrt to the internal impedance of batteries and the noise generated by them...

[TonyRPH]

kayc said:

TonyRPH said:

So, what you're saying is, that if I remove the traditional mains cable from my amp, and hardwire it with 2 core + earth mains cable as is run in the wall from the distribution board, this is better than using a 'standard' mains cable?

Obviously, no cable is impossible, unless the equipment is powered by batteries.

But this opens up a whole new can of worms, wrt to the internal impedance of batteries and the noise generated by them...

What i am saying is all cables affect the sound..what those cables are made of will clearly make them sound different...ever heard Van den Hul cables?If you cant tell the difference between them and any of the Nordost range i would have to suggest hearing difficulties.And im not implying one is better than the other..just different.

Edited by kayc on Friday 25th January 11:09

I don't dispute the fact that different interconnects sound different.

I was referring to the primary debate about mains cables, and the claims that they themselves can affect the sound.

I note that mains cables / filters etc. seem to be less popular with vision products.

Perhaps this is because we trust our eyes more than our ears?

[TonyRPH]

kayc said:

It my opinion it can improve the sound if the item it replaces is of poor construction/materials etc..as i say all cables affect sound..the better the cable the less destructive it is...i have actually heard a Naim system with a certain mains cable being used that added so much bass to the sound that it was unbearable and a kettle lead was definately better.

Dare I say it, but IMHO the Naim kit is poorly designed in the first place.

After all, any amplifier that *only* works properly with their own branded speaker cable is a disaster waiting to happen IMHO.

All for the sake of eliminating a Zobel network on the output.

Of course it makes sense to sell kit that is designed to sound better with your own range of cables, doesn't it?

/cynic mode off.

[TonyRPH]

BliarOut said:

<snip>
The only thing I think has the possibility to affect the sound *might* be a UPS to clean up the supply, however a decent PSU should be doing that anyway.
<snip>

I recently read a review of a mains regenerator.

The review was going well, until the reviewer stated that he tried a 'boutique' mains cable between the regenerator and the amp under test.

Suddenly the sound improved even more apparently.

If the mains generator was that good in the first place, why should an additional cable improve the sound I wonder?

It simply has to be a placebo effect.

I do note that many of these reviewers refuse to participate in blind tests - I guess they simply don't trust their ears, without seeing what's happening too.

[TonyRPH]

Le TVR said:

Go back to the principle of the AC port of any equipment being bi-directional.
You must consider the cable attached to this port as being an open wire transmission line and as such it will transmit/receive and couple to and from.

It's widely recognised that cables can act as antennae (I assume that's what your statement above implies).

Le TVR said:

This is why physical separation and avoidance of rat's nests is important.
However, the properties of a transmission line are directly affected by physical size, shape and spacing.

Again, I don't think there's any argument regarding separation of cables etc. and of course length will determine resonance frequency, just like an antenna.

Le TVR said:

I have never heard it but there may be a rationale behind certain cables. BUT to me that would indicate a problem elsewhere between the equipment in question for being susceptible in the first place. Therefore the likelyhood of any cable working better than any other is extremely equipment and physical placing dependant etc etc.

Having spent many years working on various electronic equipment (mostly domestic) - it's abundantly clear that not all equipment is created equally (certainly with regard to PSU design / filtering / mains input treatment).

Le TVR said:

The hypothesis is extremely tenuous but that seems to be what a lot of snake oil products exploit.
I would rather search for the root problem that adopt a sticking plaster solution.

Tenuous indeed - but if it keeps the money rolling in..

Le TVR said:

My supply is also a dedicated spur but L+N are made up as a twisted pair in 4mm with separate earth. Equipment AC cables are also similar twisted pair.

I'm not so sure about twisted mains cables - I can certainly see a beneficial screening (and possibly even reduction of radiated field) effect, but I'm not sure if the additional inductance created is in any way beneficial?

[TonyRPH]

custodian said:

Well, in a controlled series of listening tests with several listeners of different backgrounds, there were consistent conclusions where some were better, some were worse and some couldn't be differentiated. Nobody knew which cables they were listening to. How does a placebo effect play out in that scenario. Placebo effect, by definition, requires a particular expectation.

Surely expectations are set by the very purpose of the listening panel being there in the first place?

[TonyRPH]

BliarOut said:

<snip>
You ever seen a UPS input graph? UK mains is all over the shop.

Where I am, my mains is reasonably stable and noise free.

Here is a graph from one of my UPS'

Apologies for the resolution - it's relatively coarse.

[TonyRPH]

custodian said:

Tony, you are very fortunate where you live. Ours is nothing like that!

I reckon I must be.

Unfortunately, we're more challenged by the proximity of the Leeds Bradford airport, which is approximately 2 miles away 'as the crow flies' and getting decent FM reception is quite difficult for long distance stations.

I have a dipole antenna in my loft, directed away from the airport, so I can receive most of the strong stations, but DX'ing is a non starter.

Manually tuning through the FM waveband results in a variety of whistles, whines and various other 'interesting' sounds in between the stronger stations.

But I digress...

[TonyRPH]

For those interested in mains voltage and frequency - you may find this site to be of interest.

It's particularly interesting to watch during Coronation Street when the adverts come on.

[TonyRPH]

tank slapper said:

I think the point is that the electricity supply varies in both voltage and frequency and noise, sometimes quite considerably. If the minuscule electrical effects of changing a mains cable are audible, then surely these much larger effects must also be audible. What is more, since they are comparatively huge, their effect must be catastrophic on the sound you hear.

Mains voltage fluctuations should pass unnoticed to equipment with (properly) regulated supplies.

This will include the vast majority of HiFi equipment, with the exception of power amplifiers, which rarely have regulated supplies.

And power amplifiers usually have large value reservoir capacitors, which (when the amp is idle) will soak up these fluctuations.

During music playback, the power supply within the amp will be showing some fluctuation anyway, so unless the mains voltage changes dramatically (and suddenly) it's likely that such an event will pass unnoticed by the listener.

Many of the amps I build do not have protection relays on the speaker outputs, and when playing music at a relatively low level, it is actually possible to turn the power off, and the music will continue playing for 10 - 15 seconds (depending on volume level).

[TonyRPH]

tank slapper said:

Yes, I realise all that. I was trying to point out the absurdity of suggesting that the absolutely tiny differences between various mains cables make a difference to how a system sounds, yet the very much larger differences that occur from minute to minute in the mains supply are somehow not audible. Any system that it is possible to hear such a difference on has a pretty stty designed power supply in my opinion. This whole mains lead thing is completely ridiculous.

Agreed.

[TonyRPH]

anonymous said:

[redacted]

From what I can tell from the pictures, very little (if any) of the actual signal is carried by any internal wiring.

It looks as though it's all concentrated on the two PCBs (for each channel).

I'm not quite sure why they required two stepper motors to drive the balanced volume control though, given that they are (apparently) linked mechanically via a belt drive.

The chassis, although a work of art, looks to be massively over engineered however - and looks to have been machined from a solid billet of aluminium. This can't be cheap to make.