WTB: VU Meters
 

"Eeyore" wrote in message
...


"Dave Plowman (News)" wrote:

Don Pearce wrote:

Don't forget 1 - 2 - 3 - TEST - 5 - 6 - 7 where TEST would correspond
to 0VU on a VU meter.

[Sharp intake of breath]
What a VU should read at 'zero level' is the source of many a debate. ;-)

Is it ?

It reads '0' with a 1.228 V input and loads the circuit with 7.5 kohms.


A 1.228V rms sinewave to be precise. What voltage of a non-sinewave signal
corresponds to 0VU is another thing entirely. All that matters is that all
true VU meters read the same.


David.

WTB: VU Meters
 

On Thu, 7 Feb 2008 09:19:52 -0000, "David Looser"
wrote:

"Eeyore" wrote in message
...


"Dave Plowman (News)" wrote:

Don Pearce wrote:

Don't forget 1 - 2 - 3 - TEST - 5 - 6 - 7 where TEST would correspond
to 0VU on a VU meter.

[Sharp intake of breath]
What a VU should read at 'zero level' is the source of many a debate. ;-)

Is it ?

It reads '0' with a 1.228 V input and loads the circuit with 7.5 kohms.


A 1.228V rms sinewave to be precise. What voltage of a non-sinewave signal
corresponds to 0VU is another thing entirely. All that matters is that all
true VU meters read the same.


David.


Oops, when I said 0VU, what I meant was 0dBu. 0VU is +4dBu. So a sine
wave that shows 0 on a VU meter will read 4dB above the TEST level on
a PPM.

So a 0VU sine wave will read

Almost + 6 on a Nordic PPM (IEC 60268-10/1)
5 on a BBC PPM (IEC 60268-10/11a)
+4 on an EBU PPM (IEC 60268-10/11b)

d

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

WTB: VU Meters
 

In article i,
Iain Churches wrote:
Don't forget 1 - 2 - 3 - TEST - 5 - 6 - 7 where TEST would
correspond to 0VU on a VU meter.

[Sharp intake of breath] What a VU should read at 'zero level' is the
source of many a debate. ;-)

Is it ?

It reads '0' with a 1.228 V input and loads the circuit with 7.5 kohms.

Indeed. And has done so since May 1939:-)

Well yes. Now define zero level. Which I'd guess even Decca used for line
up purposes.

VU meter characteristics were precisely defined by
ANSI specification "Volume Measurements of
Electrical Speech and Program waves" C16.5-1942
(which is now incorporated into IEC 60268-17).

On the odd occasion I've visited pro recording studios where a pop session
was in progress the VUs on the multi-track seemed to be permanently on the
end stops...;-) IMHO they're pretty useless devices for monitoring or
setting audio levels.

[Ducks] ;-)

--
*When did my wild oats turn to prunes and all bran?

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

WTB: VU Meters
 

Don Pearce wrote:

Oops, when I said 0VU, what I meant was 0dBu.

You CRIMINAL ! ;~)

Graham

WTB: VU Meters
 

"Dave Plowman (News)" wrote:

Now define zero level.

In nW/mm ?

185
200
320
something else (elevated level) when using Ampex 406/456 etc.

Graham

WTB: VU Meters
 

On Thu, 07 Feb 2008 12:46:32 +0000, Eeyore
wrote:



Don Pearce wrote:

Oops, when I said 0VU, what I meant was 0dBu.

You CRIMINAL ! ;~)

Graham

I've been beating myself with a sharp whip ever since :-)

d

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

WTB: VU Meters
 

In article ,
Eeyore wrote:


"Dave Plowman (News)" wrote:

Now define zero level.

In nW/mm ?

185
200
320
something else (elevated level) when using Ampex 406/456 etc.

It's not tape flux density. Just plain ol' 1 mW across 600 ohms.

--
*Dancing is a perpendicular expression of a horizontal desire *

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

WTB: VU Meters
 

"Don Pearce" wrote in message
...
On Thu, 07 Feb 2008 12:46:32 +0000, Eeyore
wrote:



Don Pearce wrote:

Oops, when I said 0VU, what I meant was 0dBu.

You CRIMINAL ! ;~)

Graham

I've been beating myself with a sharp whip ever since :-)



Don. We expect better of you:-)

The sentence of this court is that you be
condemned to listen to two Matt Monro
albums (vinyl of course) in succession,
on a Dansette record-player. Which during,
you shall have the succour of no man, nor the
comfort of either bread or water.

You have no right of appeal. Protest and we
shall add the complete collection of Russ Conway
singles to your already considerable punishment.

Take him down!


George Jeffreys
Judge and Solicitor General to the Duke of York

WTB: VU Meters
 

On Thu, 7 Feb 2008 19:39:42 +0200, "Iain Churches"
wrote:



"Don Pearce" wrote in message
...
On Thu, 07 Feb 2008 12:46:32 +0000, Eeyore
wrote:



Don Pearce wrote:

Oops, when I said 0VU, what I meant was 0dBu.

You CRIMINAL ! ;~)

Graham

I've been beating myself with a sharp whip ever since :-)



Don. We expect better of you:-)

The sentence of this court is that you be
condemned to listen to two Matt Monro
albums (vinyl of course) in succession,
on a Dansette record-player. Which during,
you shall have the succour of no man, nor the
comfort of either bread or water.

You have no right of appeal. Protest and we
shall add the complete collection of Russ Conway
singles to your already considerable punishment.

Take him down!


Hah! I can withstand that. At least you didn't add Mrs Mills and Max
Bygraves. That would have finished me.

d

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

WTB: VU Meters & PPMs
 

"Iain Churches" wrote in message
ti.fi...


"David Looser" wrote in message
...
"Iain Churches" wrote in message
ti.fi...



But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.


It's 28 years since I saw one, but yes I am sure they
were calibrated in dBm I may have some photos of the Neves
in Studio II, and at Tollington Park, and the Decca mixer in
Studio III. I will try to find them. The meters in copying
and cutting rooms had a red line at +8dBm, but other
versions had a red segment from +8dBm and the later
faster meters in Remix II had the red segment starting
at +12dBm.

There must have been many hundreds of these meters
in use at Decca.

Iain



I believe the larger PPM instrument showing +12dB meter scale, still with
peak 4 as 0 line-up, it had no red segment - just white characters on black
b/g, was known as the European standard PPM. It still used virtually the
same meter driver cct on a card often available in those days from the
designers Audio Engineering of Soho.
Jim