[Arny Krueger]

"Trevor Wilson" wrote in
message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP amps
to drive headphones.

Wrong. Most op-amp based headphone amps use far lower value resistors, for
pretty obvious reasons. They'd have to use a far more expensive op amp and
power supply if they used such a large resistor. Series resistors are still
often used, but they are usually of a far lower value, for example 10-50
ohms.

http://www.rane.com/pdf/hc4sch.pdf

http://www.rane.com/pdf/hc6sch.pdf

http://www.rolls.com/data/ha43man.pdf

http://www.headwize.com/projects/cmoy2_prj.htm

http://www.minidisc.org/schem.gif

http://sound.westhost.com/project109.htm



This is just plain daft. Headphones,
like speakers work best when sourced from a low impedance
source.

Agreed.

[paul packer]

On Tue, 27 Mar 2007 06:41:40 -0400, "Arny Krueger"
wrote:

"Trevor Wilson" wrote in
message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

You're a wonderful watchdog, Arnie.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP amps
to drive headphones.

Wrong.

See.

[Trevor Wilson]

"Arny Krueger" wrote in message
...
"Trevor Wilson" wrote in
message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP amps
to drive headphones.

Wrong.

**Cite your evidence. Here is MY evidence:

The Denons I previously cited use 100 Ohm resistors. The Pioneer uses 220
Ohm resistors and the Nakamichi uses 470 Ohm resistors.

Most op-amp based headphone amps use far lower value resistors, for
pretty obvious reasons. They'd have to use a far more expensive op amp
and power supply if they used such a large resistor. Series resistors are
still often used, but they are usually of a far lower value, for example
10-50 ohms.

http://www.rane.com/pdf/hc4sch.pdf

http://www.rane.com/pdf/hc6sch.pdf

http://www.rolls.com/data/ha43man.pdf

http://www.headwize.com/projects/cmoy2_prj.htm

http://www.minidisc.org/schem.gif

http://sound.westhost.com/project109.htm

**Just reminder: We're discussing DOMESTIC audio equipment. These guys use
the cheapest, crappiest ICs they can find. Usually, 4558 derivatives.




This is just plain daft. Headphones,
like speakers work best when sourced from a low impedance
source.

Agreed.

**Good.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Trevor Wilson]

"Trevor Wilson" wrote in message
.. .

"Arny Krueger" wrote in message
...
"Trevor Wilson" wrote in
message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP amps
to drive headphones.

Wrong.

**Cite your evidence. Here is MY evidence:

The Denons I previously cited use 100 Ohm resistors.

**Whoops. The Denons use 470 Ohm resistors.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Arny Krueger]

"Trevor Wilson" wrote in
message
"Trevor Wilson" wrote
in message
.. .

"Arny Krueger" wrote in message
...
"Trevor Wilson"
wrote in message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP
amps to drive headphones.

Wrong.

**Cite your evidence. Here is MY evidence:

The Denons I previously cited use 100 Ohm resistors.

**Whoops. The Denons use 470 Ohm resistors.

Prove your point like I did Trevor - post links to online schematics.

[Trevor Wilson]

"Arny Krueger" wrote in message
. ..
"Trevor Wilson" wrote in
message
"Trevor Wilson" wrote
in message
.. .

"Arny Krueger" wrote in message
...
"Trevor Wilson"
wrote in message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP
amps to drive headphones.

Wrong.

**Cite your evidence. Here is MY evidence:

The Denons I previously cited use 100 Ohm resistors.

**Whoops. The Denons use 470 Ohm resistors.

Prove your point like I did Trevor - post links to online schematics.

**I have no idea if on-line schematics exist for the models listed. I have
it on paper, right here in front of me. How much will you pay me (Paypal
will be fine) to bugger around scanning and posting COPYRIGHT material to a
place you designate? Alternatively, you could accept my word for it.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[George M. Middius]

Trevor Wilson said to DebatingTradeBorg:

How much will you pay me (Paypal
will be fine) to bugger around scanning and posting COPYRIGHT material to a
place you designate? Alternatively, you could accept my word for it.

Hahahahaha. Good one. We all know the Krooborg doesn't understand that
concept. All it cares about is the "debating trade", which means endless
arguing, quibbling, and caviling about every shred of every topic of
every thread mentioned on Usenet.




--

Krooscience: The antidote to education, experience, and excellence.

[Trevor Wilson]

"George M. Middius" cmndr _ george @ comcast . net wrote in message
...


Trevor Wilson said to DebatingTradeBorg:

How much will you pay me (Paypal
will be fine) to bugger around scanning and posting COPYRIGHT material to
a
place you designate? Alternatively, you could accept my word for it.

Hahahahaha. Good one. We all know the Krooborg doesn't understand that
concept. All it cares about is the "debating trade", which means endless
arguing, quibbling, and caviling about every shred of every topic of
every thread mentioned on Usenet.

**It seems happy to see me breach Copyright laws in the process.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Arny Krueger]

"Trevor Wilson" wrote in
message
"Arny Krueger" wrote in message
...
"Trevor Wilson" wrote
in message

As you correctly surmised, most non-headphone amp
equipped amplifiers use a 220 - 470 Ohm series resistor
to limit power to the headphones.

So far, so good.

What you may not know
is that most headphone amp equipped amplifiers use
similar value resistors in series with very cheap OP
amps to drive headphones.

Wrong.

**Cite your evidence.

I did, just below.

Most op-amp based headphone amps use far lower value
resistors, for pretty obvious reasons. They'd have to use a far more
expensive op amp and power supply if they used such a
large resistor. Series resistors are still often used,
but they are usually of a far lower value, for example
10-50 ohms. http://www.rane.com/pdf/hc4sch.pdf

http://www.rane.com/pdf/hc6sch.pdf

http://www.rolls.com/data/ha43man.pdf

http://www.headwize.com/projects/cmoy2_prj.htm

http://www.minidisc.org/schem.gif

http://sound.westhost.com/project109.htm

**Just reminder: We're discussing DOMESTIC audio
equipment. These guys use the cheapest, crappiest ICs
they can find. Usually, 4558 derivatives.

Cite your evidence - do what I did - post links to schematics.

[George M. Middius]

The Krooborg does its "debating trade" dance.

Cite your evidence - do what I did - poop out enough turds to fill a huge toilet.

Is that fair, Arnii? Trevor is only human, but you're The Poop Machine.




--

Krooscience: The antidote to education, experience, and excellence.

[dizzy]

Trevor Wilson wrote:

**Just reminder: We're discussing DOMESTIC audio equipment. These guys use
the cheapest, crappiest ICs they can find. Usually, 4558 derivatives.

Get a DAC-1. High-quality headphone amp built right in!