I hate to think, you don't expect the guy to tell everyone his voodoo
secrets?
I suppose you also use a valve to do the rectification. I suggest the 5y3
myself, though you need a specially cleaned supply for the heaters to avoid
heater/cathode intermediation distortion....

grin.

Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Bill Borland" wrote in message
...
In article
.com,
writes
On 2 Jan, 12:33, "Nick" wrote:


Don't skimp on quality, go for the best!

http://www.russandrews.com/product.a...UK&currency=GB...

In Russ's quest to extract even more

money from his customers' wallets

performance from his Hi-Fi system, he's
identified a new way of cleaning your mains supply that's even more
effective than our Ultra Purifier mains filters.

The new product 'balances' the mains and cleans the mains supply in a
completely new way; it's quite capable of lifting the performance of
your
system to a completely new level.

The principle is sound, like balanced audio circuits, it uses a
transformer with two secondaries of half the primary voltage,
connected in series, with the junction earthed and the load supplied
across the two outer ends. You could get a suitable transformer made
for much less than Russ charges.

Do you simply mean a transformer with a centre-tapped secondary, or
is there more to it than that?
--
Bill Borland
(G3EFS)

My spell checker invented the type of distortion, but actually its quite apt
considering all that heated discussion this has caused...
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Brian Gaff" wrote in message
m...
I hate to think, you don't expect the guy to tell everyone his voodoo
secrets?
I suppose you also use a valve to do the rectification. I suggest the 5y3
myself, though you need a specially cleaned supply for the heaters to
avoid heater/cathode intermediation distortion....

grin.

Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Bill Borland" wrote in message
...
In article
.com,
writes
On 2 Jan, 12:33, "Nick" wrote:


Don't skimp on quality, go for the best!

http://www.russandrews.com/product.a...UK&currency=GB...

In Russ's quest to extract even more

money from his customers' wallets

performance from his Hi-Fi system, he's
identified a new way of cleaning your mains supply that's even more
effective than our Ultra Purifier mains filters.

The new product 'balances' the mains and cleans the mains supply in a
completely new way; it's quite capable of lifting the performance of
your
system to a completely new level.

The principle is sound, like balanced audio circuits, it uses a
transformer with two secondaries of half the primary voltage,
connected in series, with the junction earthed and the load supplied
across the two outer ends. You could get a suitable transformer made
for much less than Russ charges.

Do you simply mean a transformer with a centre-tapped secondary, or
is there more to it than that?
--
Bill Borland
(G3EFS)

"Spike" wrote in message
...


Modern low-noise systems can be expected to be very much more
sensitive than those of ~75 years ago,

Do you actually mean "sensitive"? (i.e.. the input signal necessary for full
output) in which case modern domestic audio systems are no more sensitive
than those of the 1970s. Or are you saying that, being low-noise, hum will
be more apparent? But amplifier noise levels have more than adequate for
decades too, it's the background acoustic noise levels in homes which matter
here, and they have, in general, got worse in the last 50 years or so due to
higher levels of traffic noise etc.

Could it be that
bonding the neutral line to earth unbalances the mains wiring,

Well of course it unbalances it! That's the very definition of unbalanced!

leading
to residual effects that could be detected?

What "residual effects" did you have in mind?


The ADSL broadband system works as it does because the two-wire system
is balanced. Adding imbalance at the consumer end, an all-too-often
occurrence, can lead to severe MW pickup at night, and during the day
if close enough to a MW transmitter, leading to some combination of
lowered noise margins or connection speeds.


The telephone system has used balanced wiring since the 1880s, for very good
reasons. But here we are talking about a power supply. Mains transformers
inherently reject common-mode noise so it's hard to see what benefit running
balanced mains to an amplifier could have.

If you can come up with either a properly thought through theory as to the
benefits of balanced mains (not a "could it be... residual effects" kind of
half-baked hypothesis) or, better still, real evidence of an audible
improvement I'd be interested to see it. But if not.......

David.

David Looser wrote:

"Spike" wrote in message
.. .


Modern low-noise systems can be expected to be very much more
sensitive than those of ~75 years ago,

Do you actually mean "sensitive"? (i.e.. the input signal necessary for full
output) in which case modern domestic audio systems are no more sensitive
than those of the 1970s. Or are you saying that, being low-noise, hum will
be more apparent? But amplifier noise levels have more than adequate for
decades too, it's the background acoustic noise levels in homes which matter
here, and they have, in general, got worse in the last 50 years or so due to
higher levels of traffic noise etc.

I meant 'sensitive' as 'being able to detect ever smaller signals and
any previously unrecognised effects'.

Could it be that
bonding the neutral line to earth unbalances the mains wiring,

Well of course it unbalances it! That's the very definition of unbalanced!

I know that. The 'could be' was a bland way of leading on the main
point, which was:

leading to residual effects that could be detected?

What "residual effects" did you have in mind?

E/m fields affecting electron flow in valves (seen that enough times)
and perhaps conduction processes in semiconductors (not a field I'm
interested in). Doubtless there are others.

I am, like you I suspect, not an expert in low noise audio systems.

The ADSL broadband system works as it does because the two-wire system
is balanced. Adding imbalance at the consumer end, an all-too-often
occurrence, can lead to severe MW pickup at night, and during the day
if close enough to a MW transmitter, leading to some combination of
lowered noise margins or connection speeds.


The telephone system has used balanced wiring since the 1880s, for very good
reasons. But here we are talking about a power supply. Mains transformers
inherently reject common-mode noise so it's hard to see what benefit running
balanced mains to an amplifier could have.

If you can come up with either a properly thought through theory as to the
benefits of balanced mains (not a "could it be... residual effects" kind of
half-baked hypothesis) or, better still, real evidence of an audible
improvement I'd be interested to see it. But if not.......

I've no intention of coming up with 'a properly thought through
theory', and I suspect that if you could, you would have done so
before now. But to take the line that because you can't think of
something that has not yet been detected simply isn't a viable
methodology. The reverse is usually true: LHC, anyone?

--
from
Aero Spike
Not a member of the RSGB since 1959

"Spike" wrote in message
...

David Looser wrote:


Modern low-noise systems can be expected to be very much more
sensitive than those of ~75 years ago,

Do you actually mean "sensitive"?

I meant 'sensitive' as 'being able to detect ever smaller signals and
any previously unrecognised effects'.

Funnily enough many of the *real* audiphools will tell you how much better
audio is with the technology of the past. Not just valves, but directly
heated triodes, real 1930s technology.

As for "smaller signals", the dynamic range of audio really hasn't changed
that much. The limits on "smaller signals" is set by the limits of human
hearing and the acoustic environment in which we live. And, "unrecognised
effects"?, when was the last occasion a previously "unrecognised effect" was
found to matter in audio?


What "residual effects" did you have in mind?

E/m fields affecting electron flow in valves (seen that enough times)

Care to elaborate?


I've no intention of coming up with 'a properly thought through
theory',

I thought not :-) But if you think there's something in it give it a go, buy
a mains isolating transformer with a centre-tapped secondary and try it out.
Let us know how you get on.

But to take the line that because you can't think of
something that has not yet been detected simply isn't a viable
methodology.

The whole field of audio is simply crawling with half-baked nonsense There
are audiphools who fall for this crap and shysters like Russ Andrews
prepared to fleece the gullible in order to make a quick buck.

The reverse is usually true:

Not in the case of audio it isn't. Real advances are few and far between,
bogus claims like this are ten a penny.

LHC, anyone?

What on earth has the LHC got to do with it?

David.

"Brian Gaff" wrote in message
m...
When I were a lad, this was the cheapest way to get full wave
rectification.

Only two diodes needed, but wait, maybe these are special Russ
low noise matched diodes?

Brian



Ah, so what. I still have a copy of the Radio and TV valve and
transistor data book which has page headers for Geranium
transistors!

Maybe an early version of flower power?




--
Woody

harrogate three at ntlworld dot com

On 02/01/2010 22:09, Spike wrote:


Have a Google for 'humdinger' (and/or 'hum dinger').


I often wondered why the hifi brigade didn't go down the road of heating
the valves with regulated DC to minimise any induced hum, especially
where they use directly heated stuff with no cathode.

Maybe they do and I'm just not aware of it?

--
All the best for 2010 de Walter.

"Walter Raleigh" wrote in message
...
On 02/01/2010 22:09, Spike wrote:


Have a Google for 'humdinger' (and/or 'hum dinger').


I often wondered why the hifi brigade didn't go down the road of heating
the valves with regulated DC to minimise any induced hum, especially where
they use directly heated stuff with no cathode.


If you rectify AC you replace the 50Hz sinusoidal "hum" with a 100Hz "rasp".
True, you can regulate and filter but anything left will be more "hash" and
probably more in the hearing range of the ear.

As the audio guys who have joined this thread have generally acknowledged, a
lot of this "noise reduction" is in the sphere of counting angels dancing on
pin heads.

--
73
Brian G8OSN/W8OSN
www.g8osn.net

"Walter Raleigh" wrote in message
...
I often wondered why the hifi brigade didn't go down the road of heating
the valves with regulated DC to minimise any induced hum, especially where
they use directly heated stuff with no cathode.

Ah, I did that many years ago - it was a hybrid. The unit was a microphone
mixer and I used cascode triodes for the front end - decent low noise
transistors had yet to be invented. I fed the heaters via a stabilised DC
supply, using an OC35 and a zener. The result was great. Absolutely no hum
and the noise figure was within 3dB of the theoretical.
That was in the sixties. The unit is still in service.

Les.

In article , David Looser
wrote:
"Spike" wrote in message
...


I meant 'sensitive' as 'being able to detect ever smaller signals and
any previously unrecognised effects'.

As for "smaller signals", the dynamic range of audio really hasn't
changed that much. The limits on "smaller signals" is set by the limits
of human hearing and the acoustic environment in which we live.

Yes. And in addition to that, much of recorded/broadcast music in recent
years has become level-compressed, etc, to occupy far smaller dynamic
ranges that even half-decent home electronics can handle. Then stir into
the mix the use of methods like mp3... Chances are that most people are
listening to music that never needs anything like the dynamic range that
their hearing could handle, let alone that of a decent audio amp.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html