[David E. Bath]

Steve Guttenberg of CNET writes about some computer speakers that he
claims are "audiophile grade".

Anyone have an experience with them?

http://www.cnet.com/8301-13645_1-9946736-47.html?tag=bnpr

--
David Bath - RAHE Co-moderator

[Kalman Rubinson[_3_]]

On 20 May 2008 23:03:06 GMT, (David E. Bath)
wrote:

Steve Guttenberg of CNET writes about some computer speakers that he
claims are "audiophile grade".

Anyone have an experience with them?

http://www.cnet.com/8301-13645_1-9946736-47.html?tag=bnpr

See also:
http://www.stereophile.com/budgetcom...7ae/index.html

Kal

[Greg Wormald]

I know that Radio Paradise uses them in the studio, and says very nice
things about them.
Greg

[Arny Krueger]

"Greg Wormald" wrote in message


I know that Radio Paradise uses them in the studio, and
says very nice things about them.

The actual Stereophile review is at:

http://stereophile.com/standloudspea...ae/index4.html

Kind of interesting as a level set on what current speaker technology is all
about.

I thought that the AudioEngine 2 review begged comparison with this one for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I have a pair of SZs and I think I'll keep them! ;-)

[Greg Wormald[_2_]]

In article ,
"Arny Krueger" wrote:

The actual Stereophile review is at:

http://stereophile.com/standloudspea...ae/index4.html

Kind of interesting as a level set on what current speaker technology is all
about.

I thought that the AudioEngine 2 review begged comparison with this one for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I have a pair of SZs and I think I'll keep them! ;-)

I reckon if I had a pair I'd be using them on my computer.

Of course the AudioEngine 2 comes with an amplifier built-in, and for
less money than the 1994 price of the NHT. How does $230 (plus amplifier
cost) in 1994 compare to $200 today?

Greg

[Dave]

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html


I am curious about the high-pass filter employed in the article. The author
notes that the R in the RC filter is in parallel with the amplifier's output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

[Sonnova]

On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html


I am curious about the high-pass filter employed in the article. The author
notes that the R in the RC filter is in parallel with the amplifier's output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a filter
is only 3dB/octave - not very steep.

[jwvm]

On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):



"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The author
notes that the R in the RC filter is in parallel with the amplifier's output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a filter
is only 3dB/octave - not very steep.

I am sure that you meant 6 dB/octave. :-)

[[email protected]]

On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):



"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The author
notes that the R in the RC filter is in parallel with the amplifier's output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a filter
is only 3dB/octave - not very steep.

Explain, if you will, how a single-pole filter has
a slope of 3 dB/octave.

[Dave]

"Sonnova" wrote in message
...

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

How would I construct a filter, assuming the amp's impedance is the only
unchangeable constant, to give me a 6dB or 12dB per octave filter?

[Sonnova]

On Fri, 30 May 2008 07:50:09 -0700, wrote
(in article ):

On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):



"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

Explain, if you will, how a single-pole filter has
a slope of 3 dB/octave.

I'm reasonably sure that a single-pole passive high-pass filter is 3dB down
at half it's corner frequency and rolls off at a rate of 20dB/decade. The
response chart at :

http://tinyurl.com/5k4tzo

Shows the slope. If you interpolate the graph, you can see that the shown
10KHz high-pass is down by about that much at 5KHz

[Sonnova]

On Fri, 30 May 2008 07:50:27 -0700, Dave wrote
(in article ):

"Sonnova" wrote in message
...

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

How would I construct a filter, assuming the amp's impedance is the only
unchangeable constant, to give me a 6dB or 12dB per octave filter?

Add more poles. But you start adding insertion losses to the signal unless
you add amplification. If you look, I'm sure that you can find tutorials on
the web showing you how to design such a filter...

I can get you started he

http://tinyurl.com/68kcg6

[Sonnova]

On Fri, 30 May 2008 07:49:25 -0700, jwvm wrote
(in article ):

On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):



"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

I am sure that you meant 6 dB/octave. :-)

Doesn't that rather depend upon whether your talking about voltage or power?
It's been years since I've dealt with this stuff, but it seems to me that
the slope of a single-pole filter gives 3dB with voltage and 6dB with power.
I could be misremembering though.

[Arny Krueger]

"Dave" wrote in message

"Sonnova" wrote in message
...

Vin Vout
o------------||-----------------o
| 0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /
| |
o-------------------------------o

That's a classic single-pole high-pass filter "Pi"
network. But such a filter
is only 3dB/octave - not very steep.

How would I construct a filter, assuming the amp's
impedance is the only unchangeable constant, to give me a
6dB or 12dB per octave filter?

The filter as drawn is a 6 dB/octave filter, per several other earlier
posts. 12 dB/octave filters are a much more complex situation, either not
being maximally flat or active or containing inductors.

[[email protected]]

On May 31, 11:30 am, Sonnova wrote:
On Fri, 30 May 2008 07:50:09 -0700, wrote
(in article ):



On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

Explain, if you will, how a single-pole filter has
a slope of 3 dB/octave.

I'm reasonably sure that a single-pole passive high-pass
filter is 3dB down at half it's corner frequency and rolls
off at a rate of 20dB/decade.

Fine, let's assume that's true. How many octaves
are there per decade? Well, there are about 3 1/3
(since 2^3.33 ~= 10). Thus

20 dB/decade / 3.33 octaves/decade=

Hmmm, 6 dB per octave, not 3 dB/octave.

Thus, your own assertion demonstrates that
a single pole filter has a slope of 6 dB/octave
in the stop band.

The response chart at :

http://tinyurl.com/5k4tzo

Shows the slope. If you interpolate the graph,
you can see that the shown 10KHz high-pass
is down by about that much at 5KHz

No, it shows the slope asymtotically approaching
6 dB/octave. Look, for example, at the difference
between 1 kHz and 500 Hz, 200 Hz and 100 Hz,
and so on. All 6 dB/octave for single pole.

The roloff rate is NOT taken at cutoff, it's taken
in the stop band and is the ultimate roloff rate.

Constructing a 3dB/octave filter with that slope
over a wide bandwidth is not a trivial excercise,
because it implies a "half-pole" filter, somethinfg
that's mathematical nonsense. Instead, ther are
constructed using a series of poles and zeros
staggered evenly in frequency so they do a piece-
wise approximation of a 3 dB/octave slope. But,
in this case, it's a multi-pole filter that has the
(approximate) 3 dB/octave slope.

Bottom line: all of your data confirms that the
rolloff rate of the single pole filters we're talking
about is 6 dB/octave.

[jwvm]

On May 31, 11:39 am, Sonnova wrote:
On Fri, 30 May 2008 07:49:25 -0700, jwvm wrote
(in article ):



On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

I am sure that you meant 6 dB/octave. :-)

Doesn't that rather depend upon whether your talking about voltage or power?
It's been years since I've dealt with this stuff, but it seems to me that
the slope of a single-pole filter gives 3dB with voltage and 6dB with power.
I could be misremembering though.

Sorry but that is not correct. Measurements in decibels are power
ratio measurements. The 20log(Vout/Vin) type calculation can be
rewritten as 10log((Vout/Vin)^2) again showing the power relationship.
Note also that 6 dB/octave is the same slope as 20 dB/decade. The 3 dB
figure is the loss at the corner frequency of the first-order filter.

[Sonnova]

On Sat, 31 May 2008 20:12:53 -0700, wrote
(in article ):

On May 31, 11:30 am, Sonnova wrote:
On Fri, 30 May 2008 07:50:09 -0700, wrote
(in article ):



On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

Explain, if you will, how a single-pole filter has
a slope of 3 dB/octave.

I'm reasonably sure that a single-pole passive high-pass
filter is 3dB down at half it's corner frequency and rolls
off at a rate of 20dB/decade.

Fine, let's assume that's true. How many octaves
are there per decade? Well, there are about 3 1/3
(since 2^3.33 ~= 10). Thus

20 dB/decade / 3.33 octaves/decade=

Hmmm, 6 dB per octave, not 3 dB/octave.

Thus, your own assertion demonstrates that
a single pole filter has a slope of 6 dB/octave
in the stop band.

The response chart at :

http://tinyurl.com/5k4tzo

Shows the slope. If you interpolate the graph,
you can see that the shown 10KHz high-pass
is down by about that much at 5KHz

No, it shows the slope asymtotically approaching
6 dB/octave. Look, for example, at the difference
between 1 kHz and 500 Hz, 200 Hz and 100 Hz,
and so on. All 6 dB/octave for single pole.

The roloff rate is NOT taken at cutoff, it's taken
in the stop band and is the ultimate roloff rate.

Constructing a 3dB/octave filter with that slope
over a wide bandwidth is not a trivial excercise,
because it implies a "half-pole" filter, somethinfg
that's mathematical nonsense. Instead, ther are
constructed using a series of poles and zeros
staggered evenly in frequency so they do a piece-
wise approximation of a 3 dB/octave slope. But,
in this case, it's a multi-pole filter that has the
(approximate) 3 dB/octave slope.

Bottom line: all of your data confirms that the
rolloff rate of the single pole filters we're talking
about is 6 dB/octave.

OK. I mis-remembered.

[Sonnova]

On Sat, 31 May 2008 20:13:25 -0700, jwvm wrote
(in article ):

On May 31, 11:39 am, Sonnova wrote:
On Fri, 30 May 2008 07:49:25 -0700, jwvm wrote
(in article ):



On May 29, 10:56 am, Sonnova wrote:
On Wed, 28 May 2008 07:49:55 -0700, Dave wrote
(in article ):

"Arny Krueger" wrote in message
...
I thought that the AudioEngine 2 review begged comparison with this one
for
the classic NHT SZ:

http://www.stereophile.com/loudspeak...04/index9.html

I am curious about the high-pass filter employed in the article. The
author
notes that the R in the RC filter is in parallel with the amplifier's
output
impedance of 51K. Given that the amp's impedance is upstream of the
capacitor, is this right? Or did he actually construct a filter with a
rolloff frequency of 106Hz?

Vin Vout
o------------||-----------------o
0.1uF "C" of |
\ RC filter \
/ /
51K \ Amp \ 15K "R" of RC filter
/ /

o-------------------------------o

That's a classic single-pole high-pass filter "Pi" network. But such a
filter
is only 3dB/octave - not very steep.

I am sure that you meant 6 dB/octave. :-)

Doesn't that rather depend upon whether your talking about voltage or power?
It's been years since I've dealt with this stuff, but it seems to me that
the slope of a single-pole filter gives 3dB with voltage and 6dB with power.
I could be misremembering though.

Sorry but that is not correct. Measurements in decibels are power
ratio measurements. The 20log(Vout/Vin) type calculation can be
rewritten as 10log((Vout/Vin)^2) again showing the power relationship.
Note also that 6 dB/octave is the same slope as 20 dB/decade. The 3 dB
figure is the loss at the corner frequency of the first-order filter.

That must have been where I got the 3dB figure from, then. Sorry. A single
pole filter is 6dB/octave