Half-a-brain loonies and internet geeks

[Marco]

LOL. We liked the hippies - they were always considered 'cool', so we left them alone to do their shit. I had a few hippy mates at school. Our school was pretty divided, though.

There were the 'geeks' who never dressed 'cool' or tried to keep up with fashion. They were intelligent and always in the top sets at school and passed all their exams with an 'A', but total 'swots' with it, shit at sports, and never seemed to like having a laugh. They very rarely had girlfriends.

There were guys kind of in between, and then there was us - the 'cool dudes' (LOL - I know, but that was the mentality at the time! ) who used to wear all the latest gear, be good at sports, had motorbikes or cars and usually a nice looking girlfriend (although we didn't mind 'doing' the odd growler at a party if we were drunk enough ). We'd always compete with each other about who could 'pull' the nicest looking girl at school, and serious street cred was given to the one who did - that kind of shit, but were also in many cases just as intelligent as the geeks and also usually in the top sets at school. The difference was we didn't have to try as hard to pass exams and get an 'A'...

We'd be out at a party the night before an exam, roll in at funny-o-clock in the morning and still manage (just!) to get up for school (with a boot up the arse from from our parents!) do the exam, mostly passing with flying colours, or wait until the absolute last minute before completing an 'ink exercise' on the bus to school, usually the morning it was due to be handed in, as homework the teacher had given us a week before, but when it was handed in the answers were usually right. The trick was to work smart, not hard, so you paid attention in class when you needed to and larked around the rest of the time!

Whereas the 'geeks' would constantly study and always have their homework done well in advance - even go to the bloody library at lunch break and do homework or read books and stay there until the bell went, even in summer! No way - we were out playing football, smoking dope, and making all sorts of mischief until the last minute, usually coming into class covered in mud and getting 'tut, tut' looks from the 'geeks', and of course the teachers. The 'geeks' became Prefects, and we took the piss out of them. You get the picture...

Ah, those were the days!

Marco.

[Mike]

Anyone remember this bit:

one of the main differences in our mains supply to the USA is unlike our supply where we have a live, neutral, and earth, in the USA they have two lives, and the earth is either connected to true earth ground, or generally the metal chassis of equipment is connected via capacitor to either one of the lives!

I'd forgotten about the way USA mains is supplied. Two 'lives' and an earth eh?..... If you squint a bit does it look a little bit like a balanced supply to anyone else?

And what do we know about balanced systems and noise rejection?... Could it be, that the USA's mains powers system doesn't suffer as badly from noise ingress as our UK system?

Thoughts anyone?

[tfarney]

Paul,



Yes to me it makes sense as it's exactly what I was describing earlier to Tim, but put in more technical way. I completely agree with you.

Tim,

What's your opinion on what Paul has written?

Marco.

Well, to the point that I understand it, Marco, it sounds like the kind of audiophile subtlety, and there are a few of them, that I never hear. I don't assume that's because they don't exist. It could sometimes be because I don't listen for them. Doesn't keep me from questioning them and occasionally fencing with those who obsess over them, though . You and Steve have me pegged as an absolutist, and I'm far from it. A pragmatist is more like it.

Maybe the power conditioners I'm accustomed to are active? They appear to have the opposite effect described -- keeping voltage steadier than it is coming out of the wall, and reporting on it by the second. Of course I don't suppose they couldn't be active regulators containing passive filters? I'm no electrician.

Tim

[anthonyTD]

Anyone remember this bit:



I'd forgotten about the way USA mains is supplied. Two 'lives' and an earth eh?..... If you squint a bit does it look a little bit like a balanced supply to anyone else?

And what do we know about balanced systems and noise rejection?... Could it be, that the USA's mains powers system doesn't suffer as badly from noise ingress as our UK system?

Thoughts anyone?

hi mike,
you would think so, but a lot of the audiophiles i deal with in the states seem to have noise and mains problems, i know they have a wide variation on mains voltage from one state to another, also the two lives would need to be exactly out of phase with each other to get noise cancelation. the other thing most people dont take into acount when designing a piece of equipment which is dual mains ready is the mains frequency diffrence, ours being 50hz theirs 60hz, this means that a mains transformer designed here on 50hz will become more efficient when run on 60hz hence you will have a higher secondary voltage, for the same given primary voltage than over here !!!
anthony,TD...

[Mike]

Just wondered.

I remember Noel Keywood writing about building a balanced supply for his house. Was interesting if perhaps a little extreme.

[DSJR]

I've used mains filters on source components for some years as living in Luton was a nightmare for good sounding audio (it's a nightmare in other ways too, but I'll be kind on this occasion ). I read in HFN that the "filter" should have a 10 times capacity for it to work properly and I found that the Roxburgh 6A filter (£40 from Farnell) worked a treat without killing things (have I mentioned it on here before? - I'm having a senior moment...LOL).

Where we live now, the mains is as good as gold and these things are unnecessary, although I've left one on the CD player, which sounds better for it and another on the tuner, which makes not one iota of difference. The power amps and active ATC's have been left well alone, except for an habitual ferrite on the mains leads....

[anthonyTD]

Just wondered.

I remember Noel Keywood writing about building a balanced supply for his house. Was interesting if perhaps a little extreme.

Its one way of canceling out certain types of noise.
The main problem most audiophiles have is self inflicted i am afraid, they use mains conditioners to filter out the crap coming in, but then re-inject at source by using equipment with err, lets be diplomatic here, less than ideal power supplies!
the only effective way to get anywhere near the ideal is to first of all use a filter "that actualy works" in the main supply, and then one in line with each piece of equipment plugged into it, that way you could be pretty sure that your not cleaning up your mains supply, only to be re-corrupting it further down the line.
anthony,TD...

[anthonyTD]

I've used mains filters on source components for some years as living in Luton was a nightmare for good sounding audio (it's a nightmare in other ways too, but I'll be kind on this occasion ). I read in HFN that the "filter" should have a 10 times capacity for it to work properly and I found that the Roxburgh 6A filter (£40 from Farnell) worked a treat without killing things (have I mentioned it on here before? - I'm having a senior moment...LOL).

Where we live now, the mains is as good as gold and these things are unnecessary, although I've left one on the CD player, which sounds better for it and another on the tuner, which makes not one iota of difference. The power amps and active ATC's have been left well alone, except for an habitual ferrite on the mains leads....

hi dave,
i agree about the current rating on filters, its an absolute nessesity for the filter to have any chance of working without degrading the sound of your system.
anthony,TD...

[Primalsea]

I don't know is USA mains is balanced or not but for balanced lines to reject noise well the load has to be of identical impedance on both lines. I presume the output impedance also has to be identicle on both lines as well.

The other thing for balanced lines is that they are supposed to be twisted so that each line is exposed equally to any interference ie common mode.

The other thing about filters is have you ever thought about where the interference goes once its been filtered out?? It gets dumped on the earth. If your not careful you just end up with the noise getting into your equipment through the earth instead.

[anthonyTD]

I don't know is USA mains is balanced or not but for balanced lines to reject noise well the load has to be of identical impedance on both lines. I presume the output impedance also has to be identicle on both lines as well.

The other thing for balanced lines is that they are supposed to be twisted so that each line is exposed equally to any interference ie common mode.

The other thing about filters is have you ever thought about where the interference goes once its been filtered out?? It gets dumped on the earth.

If your not careful you just end up with the noise getting into your equipment through the earth instead.

agreed,
Thats why a good earth, as short as posible to ground is a must for a good low noise floor.