Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

Seems I don't have a clue. All I can think of is that
it may be could acronym for power attenuation device,
but that sounds like a stretch. The dictionary at hand
didn't help.

Can anybody out there refresh my memory?

Later...

Ron Capik
--

Ron Capik wrote:
Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

Seems I don't have a clue. All I can think of is that
it may be could acronym for power attenuation device,
but that sounds like a stretch. The dictionary at hand
didn't help.

Can anybody out there refresh my memory?

Later...

Ron Capik
--

I don't think you're off in assuming it means Power Attenuation Device.

According to http://www.ciena.com/resources/resou...ronymguide.htm
it is.
That's also what I was told it stood for.

Mg

i kind of like the term. i think of it like those air bag pads that
stunt people jump into off of buildings. if the signal is hitting the
next device too hard, the pad softens the blow.

Because it would be embarassing to call them "tampons"????

Seriously, I always assumed it was a metaphor for the function it performs.

Now, since you brought it up, I wonder what the origins are of calling
certain chord-appropriate synth patches, "pads"?

malachi

"Ron Capik" wrote in message
...
Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

Seems I don't have a clue. All I can think of is that
it may be could acronym for power attenuation device,
but that sounds like a stretch. The dictionary at hand
didn't help.

Can anybody out there refresh my memory?

Later...

Ron Capik
--

I've always assumed it was by analogy with pads used to dampen the sound
of drums, strings, etc. (BTW, it's spelled "attenuators".)

Joe Kesselman wrote:

I've always assumed it was by analogy with pads used to dampen the sound
of drums, strings, etc. (BTW, it's spelled "attenuators".)

And, unless those drums and strings and things get wet, their pads are
used to damp, not dampen, them.

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mrkesti at comcast dot net | - The Who, Bargain

Michael R. Kesti wrote:
And, unless those drums and strings and things get wet, their pads are
used to damp, not dampen, them.

I sit corrected. Sorry; running tired...

Joe Kesselman wrote:

Michael R. Kesti wrote:
And, unless those drums and strings and things get wet, their pads are
used to damp, not dampen, them.

I sit corrected. Sorry; running tired...

Nothing to add....

Later...

Ron Capik
--

To pad something is to make it softer and less dangerous, as in a
padded cell. I think that's the sense in which the word is being used.

Not wanting to attenuate anyone's enthusiasm, but I strongly suspect
that the phrase "power attenuation device" was thought up long after
"pad" came into use. It just sounds too much like all those
unconvincing ideas about what "OK" or "SOS" supposedly stand for. Also,
as a tech writer I think it's wrong to say that anything attenuates
power. "Dissipates" power, sure--but I think of attenuation as applying
more to voltage. I really have a hard time believing that "power
attenuation device" is a correct or authentic term at all.

--best regards

"Michael R. Kesti" wrote in message
...


And, unless those drums and strings and things get wet, their pads are
used to damp, not dampen, them.


Ain't that back to 'tampons' again ?

geoff

David Satz wrote:

I really have a hard time believing that "power
attenuation device" is a correct or authentic term at all.

Passive attenuation dookickey?

--
ha

David Satz wrote:
To pad something is to make it softer and less dangerous, as in a
padded cell. I think that's the sense in which the word is being used.

here I always thought it referred to the large pad of phenolic board in
said devices...

--
Aaron J. Grier | "Not your ordinary poofy goof." |
"silly brewer, saaz are for pils!" -- virt

"Ron Capik" wrote in message
...
Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

Seems I don't have a clue. All I can think of is that
it may be could acronym for power attenuation device,
but that sounds like a stretch. The dictionary at hand
didn't help.

Can anybody out there refresh my memory?

Later...

Ron Capik
--




A pad absorbs some of the abnormal shock imparted inadvertently to an
object.
To cushion = to pad.
(Clawed quadruped animals usually have spongey pads in their paws.)
"pad" is a slang term for an attenuator which is the means of cushioning
(usually passively) an excessive voltage level prior to making it usable.
It's quicker and cuter to say.
Not just found in audio, a pad can be fashioned for any medium, quoted in dB
insertion loss. Eg, a Volume control is a variable pad with a logarithmic
law.

On Wed, 26 Oct 2005 19:57:01 +0000, Malachi wrote:

Because it would be embarassing to call them "tampons"????

Seriously, I always assumed it was a metaphor for the function it performs.

Now, since you brought it up, I wonder what the origins are of calling
certain chord-appropriate synth patches, "pads"?

I guess it's because they pad out the sound.
I wonder when 'pad' was first used to describe a keyboard synth pad sound?
Probably around 1978?



malachi

I heard that it was from the very earl audio mixing desks, which didn't
have variable resistors for level, etc. but a rotary switch, with a
number of PADs to connect with as you moved the rotary switch,
connecting the signal via different resistors (thus different
attenuations). They were open to the elements, with the metal pads
visible. I remember seeing a picture of one somewhere.

Chris
(REAL string for realistic prices
http://www.chris-melchior.com/strings.htm )

Ron Capik wrote:

"why's the switch in a DI box called a pad?"

Because it switches in a pad.

Here's a better one for which I can make up a plausable answer or
three:

Q: Why is the phantom power switch on a mixer labeled "48V"

A1: Because there isn't enough room on the panel to print "PHANTOM
POWER"
A2: If they abbreviated it PH people whould think it meant "Phase"
A3: Because it's not 30V

wrote:
I heard that it was from the very earl audio mixing desks, which didn't
have variable resistors for level, etc. but a rotary switch, with a
number of PADs to connect with as you moved the rotary switch,
connecting the signal via different resistors (thus different
attenuations). They were open to the elements, with the metal pads
visible. I remember seeing a picture of one somewhere.

Plausible. I don't _think_ it's correct, but it should be. smile/

"hank alrich" wrote in message
. ..
David Satz wrote:

I really have a hard time believing that "power
attenuation device" is a correct or authentic term at all.

Passive attenuation dookickey?

--
ha\

percentage anti-gain declinator?

Ron Capik wrote in
:

Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

Seems I don't have a clue. All I can think of is that
it may be could acronym for power attenuation device,
but that sounds like a stretch. The dictionary at hand
didn't help.

Can anybody out there refresh my memory?

Later...

Ron Capik
--
The use of pad comes from the early days of 600 Ohm transformer
coupled devices, where direct connection of the output of one to
the input of a second would result in all sorts of resonant
peaks in the frequency response and instability due to reflected
impedances.

An attenuator was inserted in order to pad (as in provide a
buffer, like padding a ceramic vase for transport) the output of
one device from the input of the next.


--
Bob Quintal

PA is y I've altered my email address.

hank alrich wrote:

David Satz wrote:


I really have a hard time believing that "power
attenuation device" is a correct or authentic term at all.


Passive attenuation dookickey?

--
ha

Potentiating Attenuationizing Device?

(I first seen the term in Radio Shack
catalogs *way* back, L-pads for speaker
networks ta' take egregious tweeter
overampfullousness away ).

I figger there's a puercussion-intensive
explanation JUST AROUN' THE CORNER!

--
Les Cargill

Bob Quintal wrote:

Ron Capik wrote in
:

Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

....snip..
Ron Capik
--
The use of pad comes from the early days of 600 Ohm transformer
coupled devices, where direct connection of the output of one to
the input of a second would result in all sorts of resonant
peaks in the frequency response and instability due to reflected
impedances.

An attenuator was inserted in order to pad (as in provide a
buffer, like padding a ceramic vase for transport) the output of
one device from the input of the next.
--
Bob Quintal

That seems to have dredged up some long forgotten stuff. I dug up
some ancient class notes from the audio systems class I was taking
and page one of my notebook starts with:

Pads and Attenuaters (sic)[ I couldn't spell back then either]
Definitions:
Pad; an electronic device used to match two different impedances
while inserting some _minimum_ loss. (fixed components)

Attenuater (sic); [ ... ] used to insert a loss in a line without
causing
a mismatch. (may be variable)(only useful in pre matched systems)

[Note: I studied this in the 60's when tubes and transformers were
the norm.]

Now, by that definition the switch on the DI box isn't a pad. The
definitions may have blured with time.

Later...

Ron Capik
--

"Ron Capik" wrote in message

Definitions:
Pad; an electronic device used to match two different impedances
while inserting some _minimum_ loss. (fixed components)

That'll be a 'matching pad' then , as opposed to an 'attentuator pad'.

Attenuater (sic); [ ... ] used to insert a loss in a line without
causing
a mismatch. (may be variable)(only useful in pre matched systems)

Why can't an attenuator pad cause a Z mis-match ?

geoff

"Geoff@home" wrote:

"Ron Capik" wrote in message

Definitions:
Pad; an electronic device used to match two different impedances
while inserting some _minimum_ loss. (fixed components)

That'll be a 'matching pad' then , as opposed to an 'attentuator pad'.

Attenuater (sic); [ ... ] used to insert a loss in a line without
causing
a mismatch. (may be variable)(only useful in pre matched systems)

Why can't an attenuator pad cause a Z mis-match ?

geoff

Being as this was from class notes taken something like 40 years
ago I can't say that I remember many details. In reviewing the notes
I believe the intent of the professor was that variable devices may
not always provide an exact impedance match in both directions
for all attenuation values. As I recall, this class was from instructor's
notes and didn't have a text book. Seems he made a distinction
between pads and attenuators. Can't say I recall why.

After I graduated I worked in physical chemistry and just started
back playing with audio a few years ago ...so there's some rust
and dust.

Later...

Ron Capik
--

Ron Capik wrote in
:

Bob Quintal wrote:

Ron Capik wrote in
:

Long long ago I learned about "L" pads and "T" pads
and such. In my class the other day a student asked,
"why's the switch in a DI box called a pad?"

....snip..
Ron Capik
--
The use of pad comes from the early days of 600 Ohm
transformer coupled devices, where direct connection of the
output of one to the input of a second would result in all
sorts of resonant peaks in the frequency response and
instability due to reflected impedances.

An attenuator was inserted in order to pad (as in provide a
buffer, like padding a ceramic vase for transport) the output
of one device from the input of the next.
--
Bob Quintal

That seems to have dredged up some long forgotten stuff. I dug
up some ancient class notes from the audio systems class I was
taking and page one of my notebook starts with:

Pads and Attenuaters (sic)[ I couldn't spell back then either]
Definitions:
Pad; an electronic device used to match two different
impedances while inserting some _minimum_ loss. (fixed
components)

Attenuater (sic); [ ... ] used to insert a loss in a line
without causing
a mismatch. (may be variable)(only useful in pre matched
systems)

[Note: I studied this in the 60's when tubes and transformers
were the norm.]

Now, by that definition the switch on the DI box isn't a pad.
The definitions may have blured with time.

Later...

Ron Capik
--
Yeah definitions have blurred with time. But also the definition
of pad works for a DI box since the input and output impedances
are different ;-p

--
Bob Quintal

PA is y I've altered my email address.

Ron Capik wrote in
:

"Geoff@home" wrote:

"Ron Capik" wrote in message

Definitions:
Pad; an electronic device used to match two different
impedances while inserting some _minimum_ loss. (fixed
components)

That'll be a 'matching pad' then , as opposed to an
'attentuator pad'.

Attenuater (sic); [ ... ] used to insert a loss in a line
without causing
a mismatch. (may be variable)(only useful in pre matched
systems)

Why can't an attenuator pad cause a Z mis-match ?

geoff

Being as this was from class notes taken something like 40
years ago I can't say that I remember many details. In
reviewing the notes I believe the intent of the professor was
that variable devices may not always provide an exact
impedance match in both directions for all attenuation values.
As I recall, this class was from instructor's notes and didn't
have a text book. Seems he made a distinction between pads and
attenuators. Can't say I recall why.

Oh, you and I studied at the time when people matched input and
output impedances through transformers, and impedance mismatches
created bizarre equalization effects. The pad was to isolate one
device from the other by inserting some attenuation, while the
attenuator was just there to reduce the signal. Today every
input is bridged across a low output impedance.

After I graduated I worked in physical chemistry and just
started back playing with audio a few years ago ...so there's
some rust and dust.

Later...

Ron Capik
--


--
Bob Quintal

PA is y I've altered my email address.