[student[_3_]]

Preface: I have an Onkyo cs-415 micro system in the bedroom which I got for
usage as a wake-up alarm thru the use of its timers. the cs-415 system has
a cs-315 receiver which produce 14 w @ 8 ohm & 19 w @ 4 ohm "ftc"; the
speakers are 4 ohms.

I've been using the system also to play webradio & am thinking of replacing
the speakers with small Polk Audio speakers or something that would fit on
my bookcase headboard (max depth ~9.5 in); the speakers I seen have
impedences of 8 ohms & 20-100 watts are the recommended power to run
them. The speakers would be the Polk M10 or R150 or DCM small speakers.

Question: I remember that the Heathkit 15-20 watt amps were quite able to
power the lo-efficent Acoustic Research AR 2 to loud sounds. Is
there any reason that the speaker mfg would recommend higher
power ratings than what was quite capable in the early days? Are
current receivers/amps overblown in their pwr ratings? Are they
of less quality than the old tube stuff?

I don't listen loudly as I'm in an apt the Onkyo isn't my main system which I
have in the living room. Are speaker mfg just trying to be "safe" from lawsuits?

[Mark D. Zacharias[_2_]]

"student" wrote in message
. ..
Preface: I have an Onkyo cs-415 micro system in the bedroom which I got
for
usage as a wake-up alarm thru the use of its timers. the cs-415 system
has
a cs-315 receiver which produce 14 w @ 8 ohm & 19 w @ 4 ohm "ftc"; the
speakers are 4 ohms.

I've been using the system also to play webradio & am thinking of
replacing
the speakers with small Polk Audio speakers or something that would fit on
my bookcase headboard (max depth ~9.5 in); the speakers I seen have
impedences of 8 ohms & 20-100 watts are the recommended power to run
them. The speakers would be the Polk M10 or R150 or DCM small speakers.

Question: I remember that the Heathkit 15-20 watt amps were quite able to
power the lo-efficent Acoustic Research AR 2 to loud sounds.
Is
there any reason that the speaker mfg would recommend higher
power ratings than what was quite capable in the early days?
Are
current receivers/amps overblown in their pwr ratings? Are
they
of less quality than the old tube stuff?

I don't listen loudly as I'm in an apt the Onkyo isn't my main system
which I
have in the living room. Are speaker mfg just trying to be "safe" from
lawsuits?

Not less quality but different design objectives. Should still run your low
efficiency speakers in the bedroom scenario you describe. Continuous higher
volume would be a potential problem, mainly because the Onkyo has rather
small heat sinks.

Mark Z.

[Geoff]

student wrote:
Preface: I have an Onkyo cs-415 micro system in the bedroom which I
got for usage as a wake-up alarm thru the use of its timers. the
cs-415 system has
a cs-315 receiver which produce 14 w @ 8 ohm & 19 w @ 4 ohm "ftc"; the
speakers are 4 ohms.

I've been using the system also to play webradio & am thinking of
replacing
the speakers with small Polk Audio speakers or something that would
fit on
my bookcase headboard (max depth ~9.5 in); the speakers I seen have
impedences of 8 ohms & 20-100 watts are the recommended power to run
them. The speakers would be the Polk M10 or R150 or DCM small
speakers.

Question: I remember that the Heathkit 15-20 watt amps were quite
able to power the lo-efficent Acoustic Research AR 2 to
loud sounds. Is there any reason that the speaker mfg
would recommend higher power ratings than what was
quite capable in the early days? Are current
receivers/amps overblown in their pwr ratings? Are
they of less quality than the old tube stuff?

I don't listen loudly as I'm in an apt the Onkyo isn't my main system
which I have in the living room. Are speaker mfg just trying to be
"safe" from lawsuits?

The reason that highr power amplifiers are recommended is so they can
produce high vloumes without distortion that would otherwise be likely to
blow the speakers' tweeters. If you listen at low volumes, then you
existing amp shoul be just fine.

geoff

[Arny Krueger]

"student" wrote in message


Question: I remember that the Heathkit 15-20 watt amps
were quite able to power the lo-efficent
Acoustic Research AR 2 to loud sounds.

The AR2s were actually pretty efficient speakers by modern standards. They
also had better bass than a lot of modern speakers.

Also, in the days of the AR2s there weren't a lot of people out to listen at
120 dB.

Is there any reason that the speaker mfg would
recommend higher power ratings than what
was quite capable in the early days?

(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB is not all that much
for many people.

1/4 the efficiency, 10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.

Are current receivers/amps overblown in their pwr ratings?

100 wpc is IME a pretty useful number.

Are they of less quality than the old tube stuff?

In terms of performance a good modern SS amp is light years better in every
technical and sonic area.

I don't listen loudly as I'm in an apt the Onkyo isn't my
main system which I have in the living room. Are speaker
mfg just trying to be "safe" from lawsuits?

No, they are providing what the market demands.

[Earl Kiosterud]

"Arny Krueger" wrote in message
...


10 dB louder is 40 times the power. Do the math: 40 times 20 watts is 800 watts.



For an increase of 10 dB, you need 10 times the power.

--
Earl

[Don Pearce]

Earl Kiosterud wrote:
"Arny Krueger" wrote in message
...

10 dB louder is 40 times the power. Do the math: 40 times 20 watts is 800 watts.



For an increase of 10 dB, you need 10 times the power.


That has to be one of the stupidest snips to try and make someone look
wrong that I have ever seen.

d

[Arny Krueger]

"Earl Kiosterud" wrote in message
news:5eBYj.2858$dh.1900@trnddc05
"Arny Krueger" wrote in message
...


(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB is not all that
much
for many people.


10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.


For an increase of 10 dB, you need 10 times the power.

Agreed. See point 2 above.

Then see point 1, to see how I got to 40 times.

[Earl Kiosterud]

"Arny Krueger" wrote in message
. ..
"Earl Kiosterud" wrote in message
news:5eBYj.2858$dh.1900@trnddc05
"Arny Krueger" wrote in message
...


(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB is not all that much
for many people.


10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.


For an increase of 10 dB, you need 10 times the power.

Agreed. See point 2 above.

Then see point 1, to see how I got to 40 times.

Hey Arny,

I failed to combine your 1/4 efficiency with your 10 dB difference. Now I see what you
mean.
--
Earl

[Arny Krueger]

"Earl Kiosterud" wrote in message
news:QlEYj.22113$sX5.5434@trnddc02
"Arny Krueger" wrote in message
. ..
"Earl Kiosterud" wrote in message
news:5eBYj.2858$dh.1900@trnddc05
"Arny Krueger" wrote in message
...


(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB
is not all that much
for many people.


10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.


For an increase of 10 dB, you need 10 times the power.

Agreed. See point 2 above.

Then see point 1, to see how I got to 40 times.

Hey Arny,

I failed to combine your 1/4 efficiency with your 10 dB
difference. Now I see what you mean.

No harm, no foul. Have a nice day.

[GregS[_3_]]

In article QlEYj.22113$sX5.5434@trnddc02, "Earl Kiosterud" wrote:


"Arny Krueger" wrote in message
...
"Earl Kiosterud" wrote in message
news:5eBYj.2858$dh.1900@trnddc05
"Arny Krueger" wrote in message
...


(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB is not all that much
for many people.


10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.


For an increase of 10 dB, you need 10 times the power.

Agreed. See point 2 above.

Then see point 1, to see how I got to 40 times.

Hey Arny,

I failed to combine your 1/4 efficiency with your 10 dB difference. Now I see
what you
mean.

1/4 efficiency is a confusing term not normally used in reference to loudspeakers.
It gives me a headache. I had a pair of 2's for a bit while, while I was rebuilding them.


Whats the AR3 , about 83 dB ?
I remember a Klipsh add saying something like it takes 500 watts into an AR3 compared to 1
watt for the Klipshhorn.

greg

[Arny Krueger]

"GregS" wrote in message

In article QlEYj.22113$sX5.5434@trnddc02, "Earl
Kiosterud" wrote:


"Arny Krueger" wrote in message
. ..
"Earl Kiosterud" wrote in message
news:5eBYj.2858$dh.1900@trnddc05
"Arny Krueger" wrote in message
...


(1) Many speakers are maybe 1/4 as efficient as AR2s

(2) In the old days 95 dB was loud. These days 105 dB
is not all that much
for many people.


10 dB louder is 40 times the power. Do the math: 40
times 20 watts is 800 watts.


For an increase of 10 dB, you need 10 times the power.

Agreed. See point 2 above.

Then see point 1, to see how I got to 40 times.

Hey Arny,

I failed to combine your 1/4 efficiency with your 10 dB
difference. Now I see what you
mean.

1/4 efficiency is a confusing term not normally used in
reference to loudspeakers.
It gives me a headache. I had a pair of 2's for a bit
while, while I was rebuilding them.

Whats the AR3 , about 83 dB ?

That varies. The actual configuration of AR3s varied somewhat over the
rather long life of the model designation. And that's not even talking about
the AR3a which was a little more efficient.

I did some google searching, and found 85 dB/w for the AR3. That of course
depends on frequency. Efficiency decreased with increasing frequency for the
AR3. I had a pair of AR3 woofers. I would put their efficiency at more like
88 dB/w.

I remember a Klipsh add saying something like it takes
500 watts into an AR3 compared to 1 watt for the
Klipshhorn.

500 = + 27 dB.

Another reference put the efficiency of the Klipschorn at 104 dB/w.

104 - 85 = 19 dB.

That equates to about 80 watts for the AR3 as compared to 1 watt for the
Klipschorn.

There are modern speakers running as low as 80 dB/w.

Note that speaker efficiency is one of those specs that is very susceptible
to specsmanship. You can tweak a crossover to give a few dB extra response
at precisely the frequency you rate its efficiency. Efficiency is usually
speced in the midrange either 400 Hz or 1 kHz, which for a 3 way speaker,
may be in the range of the midrange driver, not the woofer. It's easy to
make a midrange driver that is highly efficient. If you make the speaker
sound just a little forward, you have just stepped up the speaker's
specified efficiency, while providing impressive bass extension at the same
old cost in efficiency.