What's your favourite voltage regs?
 

For 5 years of my life my job was running double-blind listening tests
etc..

I'm in complete agreement that to pass on a conclusion to a third
party who had nothing to do with an experiment needs an objective and
repeatable method.

But what if circumstances don't provide this? What if all you have is
a rank order of preference? Such a rank order could be with one, two
or twenty listeners. We admit that the method is flawed, but what do
we do with this rank order:
a) Decide that it is no better than chance and ignore it?
b) Decide that if you had to chose unknown items with no other
information than such a rank order, that your initial assumption would
be that the rank order would be a better bet than chance?

What's your favourite voltage regs?
 

On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:

It is.

but these DHT filaments are very sensitive


'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...


And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d

--
Pearce Consulting
http://www.pearce.uk.com

What's your favourite voltage regs?
 

Don Pearce wrote:
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:


It is.


but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...



And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d


Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

Having said that, it can't be that simple, a 6c33c is indirectly heated,
but it does have a huge cathode.

Anyway, more files, I emailed these links to you yesterday Don, but
maybe they got lost after the night out :-).

http://www.lurcher.org/nick/heater/2a3-sq-V.wav
http://www.lurcher.org/nick/heater/2a3-sq-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-V.wav

--
Nick

What's your favourite voltage regs?
 

In article ,
Nick Gorham wrote:
Don Pearce wrote:
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:


It is.


but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...

And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

I'm following this thread with interest. If only I understood a 10th of it.

--
*How many roads must a man travel down before he admits he is lost? *

Dave Plowman London SW
To e-mail, change noise into sound.

What's your favourite voltage regs?
 

On Wed, 23 Jan 2008 23:56:54 +0000, Nick Gorham
wrote:

Don Pearce wrote:
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:


It is.


but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...



And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d


Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

Having said that, it can't be that simple, a 6c33c is indirectly heated,
but it does have a huge cathode.

Anyway, more files, I emailed these links to you yesterday Don, but
maybe they got lost after the night out :-).

http://www.lurcher.org/nick/heater/2a3-sq-V.wav
http://www.lurcher.org/nick/heater/2a3-sq-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-V.wav

No sign of them in the inbox, I'm afraid. I'll have a listen now.


d
--
Pearce Consulting
http://www.pearce.uk.com

What's your favourite voltage regs?
 

On Thu, 24 Jan 2008 00:38:01 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Nick Gorham wrote:
Don Pearce wrote:
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:


It is.


but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...

And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

I'm following this thread with interest. If only I understood a 10th of it.

It really helps that I did all my early design work in valves. It just
wasn't audio back then - apart from the trivial amount in the TVs I
was designing.

d

--
Pearce Consulting
http://www.pearce.uk.com

What's your favourite voltage regs?
 

On Wed, 23 Jan 2008 23:56:54 +0000, Nick Gorham
wrote:

Don Pearce wrote:
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:


It is.


but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...



And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d


Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

Having said that, it can't be that simple, a 6c33c is indirectly heated,
but it does have a huge cathode.

Anyway, more files, I emailed these links to you yesterday Don, but
maybe they got lost after the night out :-).

http://www.lurcher.org/nick/heater/2a3-sq-V.wav
http://www.lurcher.org/nick/heater/2a3-sq-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-V.wav

Well, apart from a tiny difference around 25Hz which I'm pretty sure
is some interaction with the leakage inductance of the output tranny,
those curves overlay each other perfectly right up to 46kHz. The
difference you were identifying aurally was at the top end, wasn't it?
They are both on here.

http://81.174.169.10/odds/dual_fr.gif

If there is a difference it isn't in the frequency response. Do you
want to try the distortion test again in case something shows that we
didn't see using the shunt C method? Incidentally did you listen to
the test amp with and without the shunt C to check if you could still
hear the difference in that mode?

d

--
Pearce Consulting
http://www.pearce.uk.com

What's your favourite voltage regs?
 

Don Pearce wrote:

On Wed, 23 Jan 2008 23:56:54 +0000, Nick Gorham
wrote:


Don Pearce wrote:

On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:



It is.



but these DHT filaments are very sensitive

'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...



And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d


Unless the new emmiter couldn't supply enough electrons at high current
peaks or for class C use, then you might still prefer a thorated fill.

Having said that, it can't be that simple, a 6c33c is indirectly heated,
but it does have a huge cathode.

Anyway, more files, I emailed these links to you yesterday Don, but
maybe they got lost after the night out :-).

http://www.lurcher.org/nick/heater/2a3-sq-V.wav
http://www.lurcher.org/nick/heater/2a3-sq-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-I.wav
http://www.lurcher.org/nick/heater/2a3-sweep-V.wav


Well, apart from a tiny difference around 25Hz which I'm pretty sure
is some interaction with the leakage inductance of the output tranny,
those curves overlay each other perfectly right up to 46kHz. The
difference you were identifying aurally was at the top end, wasn't it?
They are both on here.

http://81.174.169.10/odds/dual_fr.gif

If there is a difference it isn't in the frequency response. Do you
want to try the distortion test again in case something shows that we
didn't see using the shunt C method? Incidentally did you listen to
the test amp with and without the shunt C to check if you could still
hear the difference in that mode?

d

Its still using the shunt C, I haven't had chance to hook up the reg
yet. I will, but it might not be until the weekend.

I could try and listen to it, ut of course I only threw one chan together.

I could try the shunt C on my 211 that I do listen to, but would have
been a pain to measure.

--
Nick

What's your favourite voltage regs?
 

"Andy Evans" wrote in message
...
For 5 years of my life my job was running double-blind listening tests
etc..

I'm in complete agreement that to pass on a conclusion to a third
party who had nothing to do with an experiment needs an objective and
repeatable method.

But what if circumstances don't provide this? What if all you have is
a rank order of preference? Such a rank order could be with one, two
or twenty listeners. We admit that the method is flawed, but what do
we do with this rank order:
a) Decide that it is no better than chance and ignore it?
b) Decide that if you had to chose unknown items with no other
information than such a rank order, that your initial assumption would
be that the rank order would be a better bet than chance?


It's your amp, and you are going to be the one listening to it, so if you
think that particular filament PSU makes the amp sound best go with it. I
don't have a problem with that. What a *do* have a problem with (and this is
not addressed to you) is when people make assertions that A *does* sound
better than B, based entirely on their own non-blind listening.

To be honest I remain unconvinced that there actually is any objective
difference in the sound of a DHT amp caused by the form of filament PSU
(unless it is grossly unsuitable). I know that sometimes my own system
sounds really good to me, and othertimes it sounds crap. The difference is
not in the system, it's in me. Human perception is a very fallible thing,
what we apparently experience is not necessarily what is objectively there.

David.

What's your favourite voltage regs?
 

In article , Don Pearce
scribeth thus
On Wed, 23 Jan 2008 20:31:49 +0000, tony sayer
wrote:

It is.

but these DHT filaments are very sensitive


'ere wot abaht puttin summatt around the filament to keep it in?.

This might catch on;!...


And suppose you coated it with something that was really good at
boiling off electrons. And suppose you gave it a bit of thermal mass
so you could use AC rather than DC to heat it. That would make a much
better valve - wouldn't it?

d

Yeah right!!, it would save the weight of all those trannies;)..
--
Tony Sayer