Which N Or P Power MOSFETs ?...

[Bill Sloman]

On Saturday, November 21, 2020 at 4:44:58 PM UTC+11, jla...@highlandsniptechnology.com wrote:

On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
palli...@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a linear
application.


** FFS post *only* on topics you know something about.

That will narrow the field right down to SFA.

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.

I hadn\'t realised that John Larkin though that he was as sweet as Phil Allison, or as smart.

The real problem here is self-delusion, and I\'m not sure that I\'ve got mine under control either.

--
Bill Sloman, Sydney

 

[bitrex]

On 11/21/2020 12:44 AM, jlarkin@highlandsniptechnology.com wrote:

On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
pallison49@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a linear
application.


** FFS post *only* on topics you know something about.

That will narrow the field right down to SFA.


..... Phil

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.

The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated and the case at 25
degrees. Amazing stuff. I try to run all linear power amps pushing 20
amps with the case at 25 degrees personally

 

[server]

On Fri, 20 Nov 2020 16:24:24 -0800 (PST), Phil Allison
<pallison49@gmail.com> wrote:

upsid...@downunder.com wrote:

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

These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

I said _speaker_ _elements_, I was not referring to speaker boxes.

** Been doing it for several decades.
Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

The 15s will be 8 ohms type and the horn driver 16 ohms, with a 18dB /oct x-over and passive EQ.

With varying audio levels and hence variable voice coil temperature
and hence resistance, this will interact with the passive crossover
reactive components, which will alter e.g. crossover frequencies.

It may also use incandescent lamps for overloaded protection in series with the feed.

If not, what is the point of making kW class full range amplifiers ?

** Be silly to make them narrow range .

The bass amplifier needs to drive high power (especially in a \"small\"
enclosure) for a long time at a time and sometimes quite reactive
loads around the speaker resonance. Often the efficiency is an issue.

Much less power is needed to drive mid/high elements, so efficiency is
not so critical, due to higher efficiency of the element and much
reduced content in the audio signal. More important parameters are
frequency response, low distortion and low noise. No need to handle
high power bass tones.

If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels.

** It actually very straight foward.

The nice thing about active speaker boxes is that you do not need long
speaker wires. Perhaps this is the reason why audiophools do not like
active speakers, since they no longer can argue with each others which
exotic speaker cable is the best .

 

[bitrex]

On 11/21/2020 3:00 AM, bitrex wrote:

On 11/21/2020 12:44 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
pallison49@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a
linear
application.


** FFS   post *only* on topics you know something about.

  That will narrow the field right down to SFA.


.....  Phil

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.



The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated

Or to avoid confusion I mean the linear region in which Rds on is
defined. Anyway point is the data sheets for switching devices don\'t
usually give you the continuous operation curves.

 

[Phil Allison]

upsid...@downunder.com wrote:

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

These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

I said _speaker_ _elements_, I was not referring to speaker boxes.

** The is no such term as \" speaker elements\" you made that up.

** Been doing it for several decades.
Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

The 15s will be 8 ohms type and the horn driver 16 ohms, with a 18dB /oct x-over and passive EQ.

With varying audio levels and hence variable voice coil temperature
and hence resistance, this will interact with the passive crossover
reactive components, which will alter e.g. crossover frequencies.

** No shit Shylock ? How did you ever figure that out?

If not, what is the point of making kW class full range amplifiers ?

** To drive composite boxes, of course.

If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels.

** It actually very straight foward.

The nice thing about active speaker boxes is that you do not need long
speaker wires.

** Listen fuckhead !!!

I am not here to provide a *venue* for you solo trumpet playing.

Go toot your off key horn somewhere else.



...... Phil

 

[Phil Hobbs]

On 11/21/20 12:41 AM, jlarkin@highlandsniptechnology.com wrote:

On Fri, 20 Nov 2020 19:44:15 +0200, Tauno Voipio
tauno.voipio@notused.fi.invalid> wrote:

On 20.11.20 19.21, George Herold wrote:
On Friday, November 20, 2020 at 11:53:12 AM UTC-5, upsid...@downunder.com wrote:
On Thu, 19 Nov 2020 05:31:20 -0800 (PST), George Herold
gghe...@gmail.com> wrote:

We are in the 140V/18A range.
Is this a linear amp? If so that\'s a lot of heat.
These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

If not, what is the point of making kW class full range amplifiers ?
If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels. Better use
active crossover so each amplifier can be optimized for required
frequency range (and power levels).
We don\'t know what the load is.... maybe he\'s built his own speakers too.
George H .
(who wonders if he\'s even built a prototype.)


To pass for the audio guys at this power level, a pair of 3-500Z\'s
is needed, or maybe a pair of 813\'s with a pair of 866A\'s in the
power supply ...

Then the problem becomes the output transformer.



Put more in parallel, or use electrostatic speakers.

Cheers

Phil \"Bigger hammer\" Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[server]

On Sat, 21 Nov 2020 07:07:41 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 11/21/20 12:41 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 19:44:15 +0200, Tauno Voipio
tauno.voipio@notused.fi.invalid> wrote:

On 20.11.20 19.21, George Herold wrote:
On Friday, November 20, 2020 at 11:53:12 AM UTC-5, upsid...@downunder.com wrote:
On Thu, 19 Nov 2020 05:31:20 -0800 (PST), George Herold
gghe...@gmail.com> wrote:

We are in the 140V/18A range.
Is this a linear amp? If so that\'s a lot of heat.
These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

If not, what is the point of making kW class full range amplifiers ?
If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels. Better use
active crossover so each amplifier can be optimized for required
frequency range (and power levels).
We don\'t know what the load is.... maybe he\'s built his own speakers too.
George H .
(who wonders if he\'s even built a prototype.)


To pass for the audio guys at this power level, a pair of 3-500Z\'s
is needed, or maybe a pair of 813\'s with a pair of 866A\'s in the
power supply ...

Then the problem becomes the output transformer.



Put more in parallel, or use electrostatic speakers.

Cheers

Phil \"Bigger hammer\" Hobbs

Buy ear buds.

John \"Leave me alone\" Larkin



--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

 

[server]

On Sat, 21 Nov 2020 03:20:17 -0800 (PST), Phil Allison
<pallison49@gmail.com> wrote:

upsid...@downunder.com wrote:

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

These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

I said _speaker_ _elements_, I was not referring to speaker boxes.


** The is no such term as \" speaker elements\" you made that up.

** Been doing it for several decades.
Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

Ooh, fancy. In the USA, we call them \"parts.\"

Elements are things like copper and radium.

The 15s will be 8 ohms type and the horn driver 16 ohms, with a 18dB /oct x-over and passive EQ.

With varying audio levels and hence variable voice coil temperature
and hence resistance, this will interact with the passive crossover
reactive components, which will alter e.g. crossover frequencies.

** No shit Shylock ? How did you ever figure that out?


If not, what is the point of making kW class full range amplifiers ?


** To drive composite boxes, of course.

If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels.

** It actually very straight foward.

The nice thing about active speaker boxes is that you do not need long
speaker wires.

** Listen fuckhead !!!

I am not here to provide a *venue* for you solo trumpet playing.

We have a person down the hill from us, teaching himself to play
trumpet at night. Luckily, it\'s a ways down the hill.

Go toot your off key horn somewhere else.



..... Phil

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

 

[server]

On Sat, 21 Nov 2020 03:00:50 -0500, bitrex <user@example.net> wrote:

On 11/21/2020 12:44 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
pallison49@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a linear
application.


** FFS post *only* on topics you know something about.

That will narrow the field right down to SFA.


..... Phil

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.



The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated and the case at 25
degrees. Amazing stuff. I try to run all linear power amps pushing 20
amps with the case at 25 degrees personally

We never believed the SOAR curves, so we just pushed them until they
exploded. We found a nice pair, n and p channel.

This makes 17 kilowatts peak, for NMR and MRI microimaging. We measure
distortion in parts-per-million.

https://www.dropbox.com/s/ow0hp4qban0i13o/L500.jpg?raw=1

https://www.dropbox.com/s/lrrhgp564oefyi8/Amp.jpg?raw=1

https://www.dropbox.com/s/qbpws16c29asaxc/PP5.JPG?raw=1

The firmware runs a realtime simulation of fet die temperature to
manage shutdown. That optimizes expensive silicon better than some
simple current limit.



--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

 

[bitrex]

On 11/21/2020 11:23 AM, jlarkin@highlandsniptechnology.com wrote:

On Sat, 21 Nov 2020 03:00:50 -0500, bitrex <user@example.net> wrote:

On 11/21/2020 12:44 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
pallison49@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a linear
application.


** FFS post *only* on topics you know something about.

That will narrow the field right down to SFA.


..... Phil

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.



The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated and the case at 25
degrees. Amazing stuff. I try to run all linear power amps pushing 20
amps with the case at 25 degrees personally





We never believed the SOAR curves, so we just pushed them until they
exploded. We found a nice pair, n and p channel.

Right, there\'s a reason they use big honkin\' celled MOSFETs rated for 50
amps pulsed to push only 5 amps at 20 Hz as half of a complimentary
source follower in a linear amp. Rds on doesn\'t increase with
temperature across the whole operating regime, at low Vgs the cells
current-hog. A source-follower operates at low Vgs. The fine print
assumption with the SOA curves tells you \"don\'t do that\"

This makes 17 kilowatts peak, for NMR and MRI microimaging. We measure
distortion in parts-per-million.

https://www.dropbox.com/s/ow0hp4qban0i13o/L500.jpg?raw=1

https://www.dropbox.com/s/lrrhgp564oefyi8/Amp.jpg?raw=1

https://www.dropbox.com/s/qbpws16c29asaxc/PP5.JPG?raw=1

The firmware runs a realtime simulation of fet die temperature to
manage shutdown. That optimizes expensive silicon better than some
simple current limit.

Even calculating on paper whether a FET used for a PWM switching
application will always be within its SOA where it\'s assumed it will
either be fully off or be in the equivalent of a BJTs saturation, with a
relatively constant low Rds_on, is kind of a pain in the rear
chicken-or-egg-problem with the info the datasheets give you, going back
and forth between the SOA and the temperature de-rating info.

The case will not be at 25 degrees C like the curve is plotted at. What
it is depends on what its Rds on is. But the Rds on depends on what the
case temperature is. Etc. Somewhere there was an article about a
systematic method for solving this problem but it\'s also kinda what
LTSpice was invented for.

 

[bitrex]

On 11/21/2020 12:24 PM, bitrex wrote:

On 11/21/2020 11:23 AM, jlarkin@highlandsniptechnology.com wrote:
On Sat, 21 Nov 2020 03:00:50 -0500, bitrex <user@example.net> wrote:

On 11/21/2020 12:44 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
pallison49@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a
linear
application.


** FFS   post *only* on topics you know something about.

   That will narrow the field right down to SFA.


.....  Phil

Really, Phil, you are unreasonably harsh on people merely because they
are foul and stupid. Not everyone can be born sweet and smart like us.



The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated and the case at 25
degrees. Amazing stuff. I try to run all linear power amps pushing 20
amps with the case at 25 degrees personally





We never believed the SOAR curves, so we just pushed them until they
exploded. We found a nice pair, n and p channel.

Right, there\'s a reason they use big honkin\' celled MOSFETs rated for 50
amps pulsed to push only 5 amps at 20 Hz as half of a complimentary
source follower in a linear amp. Rds on doesn\'t increase with
temperature across the whole operating regime, at low Vgs the cells
current-hog. A source-follower operates at low Vgs. The fine print
assumption with the SOA curves tells you \"don\'t do that\"

If you go to buy even the antique IRF510 from IR off the shelf in 2020
the datasheet says like \"The IRF510 using IR\'s patented 3rd generation
HexTrenchWell technology offers improved....\"

they\'re not the same part.

 

[Phil Hobbs]

On 11/21/20 11:06 AM, jlarkin@highlandsniptechnology.com wrote:

On Sat, 21 Nov 2020 07:07:41 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 11/21/20 12:41 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 19:44:15 +0200, Tauno Voipio
tauno.voipio@notused.fi.invalid> wrote:

On 20.11.20 19.21, George Herold wrote:
On Friday, November 20, 2020 at 11:53:12 AM UTC-5, upsid...@downunder.com wrote:
On Thu, 19 Nov 2020 05:31:20 -0800 (PST), George Herold
gghe...@gmail.com> wrote:

We are in the 140V/18A range.
Is this a linear amp? If so that\'s a lot of heat.
These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

If not, what is the point of making kW class full range amplifiers ?
If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels. Better use
active crossover so each amplifier can be optimized for required
frequency range (and power levels).
We don\'t know what the load is.... maybe he\'s built his own speakers too.
George H .
(who wonders if he\'s even built a prototype.)


To pass for the audio guys at this power level, a pair of 3-500Z\'s
is needed, or maybe a pair of 813\'s with a pair of 866A\'s in the
power supply ...

Then the problem becomes the output transformer.



Put more in parallel, or use electrostatic speakers.

Cheers

Phil \"Bigger hammer\" Hobbs

Buy ear buds.

John \"Leave me alone\" Larkin

Excuuuse me! _You\'re_ the one who\'s been complaining that a 17 amp
Class D audio amplifier isn\'t powerful enough.

Cheers

Phil Hobbs

(Who listens to music about twice a month at most, apart from church)

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Bill Sloman]

On Sunday, November 22, 2020 at 3:10:58 AM UTC+11, jla...@highlandsniptechnology.com wrote:

On Sat, 21 Nov 2020 03:20:17 -0800 (PST), Phil Allison
palli...@gmail.com> wrote:

upsid...@downunder.com wrote:

<snip>

I said _speaker_ _elements_, I was not referring to speaker boxes.


** The is no such term as \" speaker elements\" you made that up.

** Been doing it for several decades.
Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
==================================> Ooh, fancy. In the USA, we call them \"parts.\"

Your dialect is a little impoverished.

> Elements are things like copper and radium.

https://www.dictionary.com/browse/element

lists fifteen different definitions for the word \"element\" in different contexts.

The first is \"a component or constituent of a whole or one of the parts into which a whole may be resolved by analysis\" which clearly includes chemical elements , but does make room for other uses.

Phil Allison is wrong. You can talk about the elements you use to assemble into a loudspeaker. \"Components\" is the word you use when you have to go out and buy them, but \"elements\" works better if you are analysing their effects on the sound that comes out.

<snip>

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

Only for John Larkin - he can\'t design stuff by intention, because he hasn\'t got a clue what he intends to design, or why. He\'s got customers for that.

--
Bill Sloman, Sydney

 

[Bill Sloman]

On Sunday, November 22, 2020 at 3:23:20 AM UTC+11, jla...@highlandsniptechnology.com wrote:

On Sat, 21 Nov 2020 03:00:50 -0500, bitrex <us...@example.net> wrote:

On 11/21/2020 12:44 AM, jla...@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 16:27:03 -0800 (PST), Phil Allison
palli...@gmail.com> wrote:

some bit brain fuckhead wrote:
=============================

Yes also because all the graphs and safe operating area curves for
modern switching MOSFETs are of little use when they\'re used in a linear
application.


** FFS post *only* on topics you know something about.

That will narrow the field right down to SFA.

<snip>

The SOA curve in most switching device datasheets tells you e.g. that
you can push 20 amps at DC with the MOSFET saturated and the case at 25
degrees. Amazing stuff. I try to run all linear power amps pushing 20
amps with the case at 25 degrees personally

We never believed the SOAR curves, so we just pushed them until they
exploded.

That probably means that John Larkin never understood what the Safe Operating Area curves were trying to tell him. They do present a plot of safe drain currents against drain-to-source voltage which does tell you something about operating the parts outside the saturation region, despite Bitrex\'s claim to the contrary,

The data sheet for Phil Allison\'s favourite N-channel part

http://www.irf.com/product-info/datasheets/data/irfp240.pdf

shows just such a curve at figure 8.

http://www.irf.com/product-info/datasheets/data/irfp9240.pdf

shows a very similar datasheet for the P-channel part Phil reccommends. Again, the SOA curve is a figure 8.

<snipped John boasting about something some customer managed to extract from him>

--
Bill Sloman, Sydney

 

[server]

On Sat, 21 Nov 2020 18:55:08 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 11/21/20 11:06 AM, jlarkin@highlandsniptechnology.com wrote:
On Sat, 21 Nov 2020 07:07:41 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 11/21/20 12:41 AM, jlarkin@highlandsniptechnology.com wrote:
On Fri, 20 Nov 2020 19:44:15 +0200, Tauno Voipio
tauno.voipio@notused.fi.invalid> wrote:

On 20.11.20 19.21, George Herold wrote:
On Friday, November 20, 2020 at 11:53:12 AM UTC-5, upsid...@downunder.com wrote:
On Thu, 19 Nov 2020 05:31:20 -0800 (PST), George Herold
gghe...@gmail.com> wrote:

We are in the 140V/18A range.
Is this a linear amp? If so that\'s a lot of heat.
These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?

If not, what is the point of making kW class full range amplifiers ?
If you have to divide the audio spectrum to multiple speaker elements
a passive crossover becomes awkward at such power levels. Better use
active crossover so each amplifier can be optimized for required
frequency range (and power levels).
We don\'t know what the load is.... maybe he\'s built his own speakers too.
George H .
(who wonders if he\'s even built a prototype.)


To pass for the audio guys at this power level, a pair of 3-500Z\'s
is needed, or maybe a pair of 813\'s with a pair of 866A\'s in the
power supply ...

Then the problem becomes the output transformer.



Put more in parallel, or use electrostatic speakers.

Cheers

Phil \"Bigger hammer\" Hobbs

Buy ear buds.

John \"Leave me alone\" Larkin

Excuuuse me! _You\'re_ the one who\'s been complaining that a 17 amp
Class D audio amplifier isn\'t powerful enough.

It\'s pretending to be an alternator. It\'s actually very quiet, running
full blast.

Cheers

Phil Hobbs

(Who listens to music about twice a month at most, apart from church)

I\'m one of the few people, along with Horatio Hornblower, who dislikes
music.




--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

 

[Phil Allison]

Bill Sloman is So Full of Shit wrote:

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

** The is no such term as \" speaker elements\" you made that up.

Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

lists fifteen different definitions for the word \"element\" in different contexts.

** Totally irrelevant.

> Phil Allison is wrong.

** That is a brave thing to post, when you have no clue what the issue was.

> \"Components\" is the word you use when you have to go out and buy them,

** So is the collective name used for the drivers in a multi-way box.

> but \"elements\" works better if you are analysing their effects on the sound that comes out.

** An entirely separate context.

The fuckwit OP posted this complete drivel:

\" These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?
If not, what is the point of making kW class full range amplifiers ? \"

** Care to translate any of that *gobbledegook* into plain English that makes technical sense ?

Go ahead.... make my day.


....... Phil

 

[Bill Sloman]

On Sunday, November 22, 2020 at 2:24:58 PM UTC+11, palli...@gmail.com wrote:

Bill Sloman is So Full of Shit wrote:

===========================
** The is no such term as \" speaker elements\" you made that up.

Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

lists fifteen different definitions for the word \"element\" in different contexts.

** Totally irrelevant.

Phil Allison is wrong.

** That is a brave thing to post, when you have no clue what the issue was.

The issue was a linguistic one, which you don\'t seem to want to think about..

\"Components\" is the word you use when you have to go out and buy them,

** So is the collective name used for the drivers in a multi-way box.

In a particular context.

but \"elements\" works better if you are analysing their effects on the sound that comes out.

** An entirely separate context.

That\'s what I was saying.

The fuckwit OP posted this complete drivel:
\" These days, are they really making full range (20 Hz .. 20 kHz)
speaker elements that can handle 1 kW power levels ?
If not, what is the point of making kW class full range amplifiers ? \"

** Care to translate any of that *gobbledegook* into plain English that makes technical sense ?

There are people who are devoted to the idea of using a single driver to cover the entire audio spectrum - from 20Hz to 20kHz. I\'ve seen a write-up of a huge full range electrostatic speaker that was intended to do just that. Not having to worry about cross-overs is an advantage of this approach, but not a compelling one

Nobody sane seems to bother, and the only bit of the audio range that needs kilowatt power is the low frequency end, so why bother making a high power amplifier that can handle any frequency higher than a couple of hundred Hz?

> Go ahead.... make my day.

Enjoy.

--
Bill Sloman, Sydney

 

[Phil Allison]

Bill Sloman wrote:
===============

The data sheet for Phil Allison\'s favourite N-channel part
http://www.irf.com/product-info/datasheets/data/irfp240.pdf
shows just such a curve at figure 8.
---------------------------------------------------------------------------

** That curve shows a limit at 100V and 3A for 10ms.
10ms is a long time in audio, when considering reactive load driving ability.

https://www.onsemi.com/pub/Collateral/MJL21193-D.PDF

This common BJT has a limit at 100V of 2A - but for 1 second.
Big difference.

https://www.datasheets360.com/pdf/-60837881188089191

This \" lateral mosfet \" is rated for 4A and 100V for 10ms and 1.25A for 1 second.

FYI:

In actual use and abuse, the last example has proven to be the least likely to fail.
Mainly because of an un-speced parameter:

The gate forward voltage rises with chip temp, so a 12V zener clamp on the gate prevents failure.
Max available current falls to 2 or 3A, the chip reaches 170C and there is no further temp rise.

I have seen products using these mosfets where the cooling fan failed, the amp lost most of its power but nothing more.

More impressively, one product (made by UK firm H-H ) where the mounting bolts *all* worked loose after thousands of thermal cycles, the devices were all floating loose yet not a single failure seen.

Gotta love that.

....... Phil

 

[Phil Allison]

Bill Sloman is Besoted with his own bullshit.

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

** The is no such term as \" speaker elements\" you made that up.

Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

lists fifteen different definitions for the word \"element\" in different contexts.

** Totally irrelevant.

Phil Allison is wrong.

** That is a brave thing to post, when you have no clue what the issue was.
The issue was a linguistic one,

** Correct use of terminology.

\"Components\" is the word you use when you have to go out and buy them,

** So is the collective name used for the drivers in a multi-way box.
In a particular context.

** The one we were in.

Rest of Bill\'s meaningless opinion sprouting deleted.

To spare gentle readers the pain.


...... Phil

 

[Bill Sloman]

On Sunday, November 22, 2020 at 3:18:43 PM UTC+11, palli...@gmail.com wrote:

Bill Sloman is Besoted with his own bullshit.

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

** The is no such term as \" speaker elements\" you made that up.

Cabs with two high power 15 inch drivers and a large format horn cater for 1kW amps fine.

That is three elements and some sort of crossover.

** FFS the correct term is \"components\" !!!
===================================

lists fifteen different definitions for the word \"element\" in different contexts.

** Totally irrelevant.

Phil Allison is wrong.

** That is a brave thing to post, when you have no clue what the issue was.
The issue was a linguistic one,
** Correct use of terminology.
\"Components\" is the word you use when you have to go out and buy them,

** So is the collective name used for the drivers in a multi-way box.

In a particular context.

** The one we were in.

The one you were in. Upside-down-under was being a bit more analytic.

Rest of Bill\'s meaningless opinion sprouting deleted.

To spare gentle readers the pain.

Phil in his Flyguy emulation mode, where he snips anything he can\'t understand.

--
Bill Sloman, Sydney