"Jerry Stuckle" wrote in message
...


OK, so instead of putting out 100W to one eight-ohm speaker, you're
putting out 100W to two eight ohm speakers. So you have a 3db gain,
assuming the speakers are in phase.

It is no different than feeding two eight-ohm speakers from separate 100W
amplifiers, and the results are the same.

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at Radio
City Music Hall in New York. He told me the sound system used amplifiers
rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use today.
Use for perspective only, please.

"Sal"

"Sal" salmonella@food poisoning.org wrote:
"Jerry Stuckle" wrote in message
...


OK, so instead of putting out 100W to one eight-ohm speaker, you're
putting out 100W to two eight ohm speakers. So you have a 3db gain,
assuming the speakers are in phase.

It is no different than feeding two eight-ohm speakers from separate 100W
amplifiers, and the results are the same.

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at Radio
City Music Hall in New York. He told me the sound system used amplifiers
rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use today.
Use for perspective only, please.

"Sal"

Some of the early amps were smaller. I remember a discussion about a movie
coming in that suggested higher power. Those speakers were typically at
least 100 times more power efficient than average home speakers, or 10 dB
spl. Many were altec a7's.

Greg

On 1/10/2014 12:45 AM, Sal wrote:
"Jerry Stuckle" wrote in message
...


OK, so instead of putting out 100W to one eight-ohm speaker, you're
putting out 100W to two eight ohm speakers. So you have a 3db gain,
assuming the speakers are in phase.

It is no different than feeding two eight-ohm speakers from separate 100W
amplifiers, and the results are the same.

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at Radio
City Music Hall in New York. He told me the sound system used amplifiers
rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use today.
Use for perspective only, please.

"Sal"



Yes, this is where speaker efficiency comes into play. Due to the need
for stiffer cones, larger voice coils, etc., higher-power speakers are
generally less efficient than lower power ones. So 10W into a 10W-rated
speaker will provide a higher SPL than that same 10W into a 100W speaker.

And, of course, speaker placement is also critical, especially in larger
venues. You can cover a large area with not a lot of power if the
system is designed properly.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.

==================

"Sal" salmonella@food poisoning.org wrote in message
...

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at Radio
City Music Hall in New York. He told me the sound system used amplifiers
rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use
today. Use for perspective only, please.

I wonder if that was 'real watts' instead of inflated watts. I have seen
some wall wart computer speakers rated at 50 watts or so. Open them up and
inside the speaker may have 3 watts on the lable.

Same as with the listed gain of antennas for hams and especially the CB.
One antenna of modern times had a gain listed of several times more than it
should. Claimed to be the gain from one of the computer programs. It may
have been,but they were adding in a lot of ground gain and certain take off
angles.

Not sure where they were getting the gain numbers from,but he old CC 11
element 2 meter beams had a number that was way too high if you compaired it
on the air with another antenna.



---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

On 1/10/2014 11:03 AM, Ralph Mowery wrote:
"Sal" salmonella@food poisoning.org wrote in message
...

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at Radio
City Music Hall in New York. He told me the sound system used amplifiers
rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use
today. Use for perspective only, please.

I wonder if that was 'real watts' instead of inflated watts. I have seen
some wall wart computer speakers rated at 50 watts or so. Open them up and
inside the speaker may have 3 watts on the lable.

Same as with the listed gain of antennas for hams and especially the CB.
One antenna of modern times had a gain listed of several times more than it
should. Claimed to be the gain from one of the computer programs. It may
have been,but they were adding in a lot of ground gain and certain take off
angles.

Not sure where they were getting the gain numbers from,but he old CC 11
element 2 meter beams had a number that was way too high if you compaired it
on the air with another antenna.




If it was a long time ago, I suspect it was "real watts". Manufacturers
didn't really start inflating the wattage until the 70's or so.

Nowadays, a "100W" amplifier is probably more like 20 "real" watts.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

"Ralph Mowery" wrote in message
m...

"Sal" salmonella@food poisoning.org wrote in message
...

Discussion of audio amplifier power in home systems always prompts me to
relate this: I worked for a guy who was formerly a projectionist at
Radio City Music Hall in New York. He told me the sound system used
amplifiers rated at 70 watts per channel. That's a 6,000-seat theater.

He worked there a long time ago, so this not a claim of what they use
today. Use for perspective only, please.

I wonder if that was 'real watts' instead of inflated watts. I have seen
some wall wart computer speakers rated at 50 watts or so. Open them up
and inside the speaker may have 3 watts on the lable.

Same as with the listed gain of antennas for hams and especially the CB.
One antenna of modern times had a gain listed of several times more than
it should. Claimed to be the gain from one of the computer programs. It
may have been,but they were adding in a lot of ground gain and certain
take off angles.

Not sure where they were getting the gain numbers from,but he old CC 11
element 2 meter beams had a number that was way too high if you compaired
it on the air with another antenna.

Hard to know, Ralph. Some years ago, I was the repairman for my son's high
school music group, a show choir that traveled with a serious suite of
electronics. One evening, I changed a bad tweeter in a big roll-around
speaker system and tested it before I put it in my van. I clipped leads on
the speaker terminals and plugged into the headphone jack on a small
boombox -- powered by four D-cells. When I began to crank it up on the
patio, my lovely wife came roaring out and demanded that I turn it down.
"Do you know what time it is?"

Well, yes, I did know, but that wasn't exactly her point. Clearly, four
D-cells provide more than enough sound power to upset a whole neighborhood
and she felt the need to heighten my concern. ;-)

"Sal"