Sign in with
Sign up | Sign in
Your question

Amps Up To 40 KHz?

Last response: in Home Audio
Share
Anonymous
December 21, 2004 1:10:18 PM

Archived from groups: rec.audio.pro (More info?)

Now that we've found those supertweeters from Scan Speak, Vifa and
Townshend, we need an amp to drive 'em.

Most of the pro audio and audiophile amps are only specified up to 20
KHz though in magazine (e.g., Stereophile) reviews some of them measure
well to beyond 40 KHz. Bryston, Parasound, Halcro and Aragon are among
these. Some have their -3dB points at beyond 100 KHz.

Might someone have a recommendation for an amp that's stable, reasonably
powerful, and that can drive a 4 Ohm load at 40 KHz?

TIA!


--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912

More about : amps khz

Anonymous
December 21, 2004 8:01:36 PM

Archived from groups: rec.audio.pro (More info?)

"Len Moskowitz" <moskowit@panix.com> wrote in message
news:cq9ecq$5d6$1@panix3.panix.com...
> Now that we've found those supertweeters from Scan Speak, Vifa and
> Townshend, we need an amp to drive 'em.
>
> Most of the pro audio and audiophile amps are only specified up to 20
> KHz though in magazine (e.g., Stereophile) reviews some of them measure
> well to beyond 40 KHz. Bryston, Parasound, Halcro and Aragon are among
> these. Some have their -3dB points at beyond 100 KHz.
>
> Might someone have a recommendation for an amp that's stable, reasonably
> powerful, and that can drive a 4 Ohm load at 40 KHz?

McIntosh MC-275. The one in my basement came from a laboratory at a local
university that was using it to amplify bat sounds up in the 60-75 kHz
region.

Peace,
Paul
Anonymous
December 22, 2004 3:20:14 AM

Archived from groups: rec.audio.pro (More info?)

As you said, Bryston. If you are puting more than a few tens of
continuous watts thru, you may have to supply external ventilation.

--
Eric (Dero) Desrochers
http://homepage.mac.com/dero72

Hiroshima 45, Tchernobyl 86, Windows 95
Related resources
Anonymous
December 22, 2004 1:24:19 PM

Archived from groups: rec.audio.pro (More info?)

"Len Moskowitz"
> Now that we've found those supertweeters from Scan Speak, Vifa and
> Townshend, we need an amp to drive 'em.
>
> Most of the pro audio and audiophile amps are only specified up to 20
> KHz though in magazine (e.g., Stereophile) reviews some of them measure
> well to beyond 40 KHz. Bryston, Parasound, Halcro and Aragon are among
> these. Some have their -3dB points at beyond 100 KHz.
>
> Might someone have a recommendation for an amp that's stable, reasonably
> powerful, and that can drive a 4 Ohm load at 40 KHz?
>


** There would be very few hi-fi amps that cannot.

You are fretting over nothing.





............... Phil
Anonymous
December 22, 2004 1:24:20 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message...

> You are fretting over nothing.


Certainly nothing that would be audible to humans.
Anonymous
December 22, 2004 1:24:20 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison <philallison@tpg.com.au> wrote:

> ** There would be very few hi-fi amps that cannot.

Well, if you look at the frequency response, distortion, separation and
power output specs on most of the low- and medium- priced amps that are
out there, they look pretty bad at 40 KHz, especially when measuring at
rated power. And then there's a question of simple stability.

Most manufacturers spec their amps up to 20 KHz, and when you ask what
they'll do at 40 KHz, the general answer is that they don't know and
won't recommend their use.

Even the high-end amps I mentioned seem somewhat questionable. Bryston,
for example, starts to hedge their specs when driving speaker impedances
of 4 Ohms or less.


--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 22, 2004 1:24:21 PM

Archived from groups: rec.audio.pro (More info?)

> Well, if you look at the frequency response, distortion, separation and
> power output specs on most of the low- and medium- priced amps that are
> out there, they look pretty bad at 40 KHz, especially when measuring at
> rated power. And then there's a question of simple stability.

But you don't need full power at 40kHz, unless you're trying to deafen bats.

Almost any decent amplifier should get to 40kHz -- or even much farther -- at
normal listening levels. Remember that the HF content of acoustic music starts
rolling off above 2kHz or so.
Anonymous
December 22, 2004 1:24:21 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message

> ** There is no "stability" issue whatever.
>
> ** That is purest bullshit !
>
> You have made a series of alarmingly false assumptions.


Phuckit... spray it with some W.... nevermind
Anonymous
December 22, 2004 1:24:21 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison <philallison@tpg.com.au> wrote:

>> Well, if you look at the frequency response, distortion, separation and
>> power output specs on most of the low- and medium- priced amps that are
>> out there, they look pretty bad at 40 KHz, especially when measuring at
>> rated power.
>
>
>** You do * NOT * need full rated power at 40 kHz to drive some wanky
>tweeter.

Oddly enough, we do.

>> And then there's a question of simple stability.
>
>
>** There is no "stability" issue whatever.

There is potentially a problem at full power at 40 KHz into some
interestingly complex impedancs.

> You do not need rated power at 40 kHz, or 20kHz, or 10 kHz or even 5 kHz to
>reproduce music programme.

Who said we were working with music?

> Normal music programme usage is another one entirely.
>
> You have made a series of alarmingly false assumptions.

I know what my application is. Do you?

--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 22, 2004 1:24:22 PM

Archived from groups: rec.audio.pro (More info?)

William Sommerwerck <williams@nwlink.com> wrote:

>> Well, if you look at the frequency response, distortion, separation and
>> power output specs on most of the low- and medium- priced amps that are
>> out there, they look pretty bad at 40 KHz, especially when measuring at
>> rated power. And then there's a question of simple stability.
>
>But you don't need full power at 40kHz, unless you're trying to deafen
>bats.

Sounds like an interesting application!

In our application, we actually need full power.

--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 22, 2004 1:24:22 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison <philallison@tpg.com.au> wrote:

> How about you reveal the ***SECRET*** application ???

But then it wouldn't be a secret any more, Phil.

>> Who said we were working with music?
>
>
>** If it is **NOT** a music application why the HELL are you trying to
>use a bloody ***hi-fi*** amp ???

Because audio amps are the most cost effective.

If you can recommend *any* amp that will put out 150 to 400 Watts at 4
Ohms into a reactive impedance, and is essentially unconditionally
stable at 40 KHz, it would help.

>> I know what my application is. Do you?
>
> ** Anyone who was not a pig ignorant turd would have revealed the
>application.
>
> The application determines what sort of amp you need -
>arsehole.

You're an interesting fellow, Phil.

--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 22, 2004 1:24:22 PM

Archived from groups: rec.audio.pro (More info?)

>> You have made a series of alarmingly false assumptions.

> I know what my application is. Do you?

Which is why, when asking for advice, you should give all the details. This is
the reason I rarely respond any more to requests for information.
Anonymous
December 22, 2004 1:24:23 PM

Archived from groups: rec.audio.pro (More info?)

not sure if you lurk around here often or whether you have just come here
for this question.
Do not get overly concerned about Phil. this is how he is.
When he gives out information it can be very useful. he is a pretty clever
guy.
But well... this is his normal sense.

Do a google groups search for things he's said on this group and also
alt.audio.pro.livesound


His original information is almost correct.
Its not a major concern. an amp will noramlly deliver a reasonably close
effort to rated powere at 40kHz

Rob
Anonymous
December 22, 2004 1:24:23 PM

Archived from groups: rec.audio.pro (More info?)

On 21 Dec 2004 22:38:53 -0500, moskowit@panix.com (Len Moskowitz)
wrote:

>If you can recommend *any* amp that will put out 150 to 400 Watts at 4
>Ohms into a reactive impedance, and is essentially unconditionally
>stable at 40 KHz, it would help.

Unconditional stability implies independance of frequency, but
we probably know what you mean, thermal stability.

All modern amplifiers have increasing internal losses from
common mode conduction. Reactive loads reflect all of the
output current back into the amplifier. You're wanting something
to survive this "perfect storm" combo.

Old-fashioned vacuum tube amplifiers didn't have problems with
these conditions, but weren't commonly made in such large sizes.

If you're really intending to drive a single dome tweeter, none
of this will matter, because the tweeter's RMS dissipation will be
about three watts in a cold room.

But you're apparently working on something more interesting, so
......maybe one of the larger Adcom MOSFET-based hi-fi amplifiers?
I've tested a 5503 to full rails into a capacitive load without
drama. Can you specify the load?

Chris Hornbeck
Anonymous
December 22, 2004 2:17:15 PM

Archived from groups: rec.audio.pro (More info?)

In article <cqaq8d$mm8$1@panix1.panix.com> moskowit@panix.com writes:

> If you can recommend *any* amp that will put out 150 to 400 Watts at 4
> Ohms into a reactive impedance, and is essentially unconditionally
> stable at 40 KHz, it would help.

You should know by now that being *helpful* is against Phil's nature.
He's only argumentive. If he can't argue with what you said, he'll
imply that you said something else that he CAN (and does) argue about.
Then he'll call you names.

I've figured him out. He brings a little cheer to this sometimes dull
newsgroup.


--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
December 22, 2004 2:49:38 PM

Archived from groups: rec.audio.pro (More info?)

On Wed, 22 Dec 2004 07:29:58 GMT, "David Morgan \(MAMS\)"
<mams@NOSPAm-a-m-s.com> wrote:

>I have nothing to add... except some WD-40. <snip>

Why not do the proper thing and add him to your kill file? Life's too
short for psychiatric cases with Usenet access.


dB
Anonymous
December 22, 2004 3:28:54 PM

Archived from groups: rec.audio.pro (More info?)

Paul Stamler <pstamlerhell@pobox.com> wrote:
>"Len Moskowitz" <moskowit@panix.com> wrote in message
>news:cq9ecq$5d6$1@panix3.panix.com...
>> Now that we've found those supertweeters from Scan Speak, Vifa and
>> Townshend, we need an amp to drive 'em.
>>
>> Most of the pro audio and audiophile amps are only specified up to 20
>> KHz though in magazine (e.g., Stereophile) reviews some of them measure
>> well to beyond 40 KHz. Bryston, Parasound, Halcro and Aragon are among
>> these. Some have their -3dB points at beyond 100 KHz.
>>
>> Might someone have a recommendation for an amp that's stable, reasonably
>> powerful, and that can drive a 4 Ohm load at 40 KHz?
>
>McIntosh MC-275. The one in my basement came from a laboratory at a local
>university that was using it to amplify bat sounds up in the 60-75 kHz
>region.

Note that you have to derate it considerably, though. My Citation II has
a -3dB corner at around 60 KC if you're only running 2W through it. At rated
power, the transformer is not as happy.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
December 22, 2004 3:52:30 PM

Archived from groups: rec.audio.pro (More info?)

DeserTBoB wrote:

> On Wed, 22 Dec 2004 07:29:58 GMT, "David Morgan \(MAMS\)"
> <mams@NOSPAm-a-m-s.com> wrote:
>
>
>>I have nothing to add... except some WD-40. <snip>
>
>
> Why not do the proper thing and add him to your kill file? Life's too
> short for psychiatric cases with Usenet access.




I used WD-40 on my killfile and now it doesn't work. I realize now I
should have used tape.
Anonymous
December 22, 2004 6:22:35 PM

Archived from groups: rec.audio.pro (More info?)

"Rob Beech" = bad advice spewing dickhead


(snip gratuitous abuse from a grade A know nothing jerk off. )



>
> His original information is almost correct.


** It was absolutely correct in the context of music programme.


> Its not a major concern. an amp will normally deliver a reasonably close
> effort to rated powere at 40kHz
>


** Normal hi-fi amps will not do any such thing CONTINUOUSLY !!!

The output devices, if bipolar, will overheat and the amp will likely blow
up.

Even if the outputs are mosfets, the usual load stabilising network ( ie
zobel) will burn up and fill the room with smoke - then amp will become
unstable for SURE.

The stupid, damn donkey brained OP will not say what the operating
conditions are so NO answer is possible.




.............. Phil
Anonymous
December 22, 2004 6:22:36 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:32sb48F3pr709U1@individual.net...

> The stupid, damn donkey brained OP will not say what the operating
> conditions are so NO answer is possible.

Phil, the operating conditions are basically along the lines of: "will
deliver a reliable, consistent power output at up to 40k"; so what
difference does it make what he's actually using it for?

Yes, looking forward to another insulting response, but holding out hope
that one day you'll grow up.

Neil Henderson
Anonymous
December 22, 2004 7:11:15 PM

Archived from groups: rec.audio.pro (More info?)

"Neil Henderson"
> "Phil Allison"
>
>> The stupid, damn donkey brained OP will not say what the operating
>> conditions are so NO answer is possible.
>
> Phil, the operating conditions are basically along the lines of: "will
> deliver a reliable, consistent power output at up to 40k";


** What wet dream did that info come to you in ??


> so what difference does it make what he's actually using it for?
>


** So I can tell what the technical requirements are - since the OP is
too thick to get to first base on them.


> Yes, looking forward to another insulting response,



** Go drop dead you useless, arrogant, failed musician, POS.






.............. Phil
Anonymous
December 22, 2004 7:11:16 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:32sdvgF3puieqU1@individual.net...

> ** What wet dream did that info come to you in ??

No wet dream, just an assessment of the posts.

>> so what difference does it make what he's actually using it for?

> ** So I can tell what the technical requirements are - since the OP
> is too thick to get to first base on them.

It seems he has a general idea, at least... he's looking for some guidance,
is all - something which you are apparently unequipped to provide.

> ** Go drop dead you useless, arrogant, failed musician, POS.

This is the second time you're referred to me as a "failed musician"...
where do you get that from? My credits in both musician & engineering
categories are certainly FAR less than many of those on this newsgroup, but
I think are also far greater than yours in either classification. Want to
name an independent accounting firm & publicly swap W2's here on this NG to
see who's the success & who's the failure? Arrogant? Maybe sometimes, but
then that's a foible of mine that I can certainly work on. Failed? Never.

Love, Neil
Anonymous
December 22, 2004 7:36:16 PM

Archived from groups: rec.audio.pro (More info?)

William Sommerwerck wrote:
>>>You have made a series of alarmingly false assumptions.
>
>
>>I know what my application is. Do you?
>
>
> Which is why, when asking for advice, you should give all the details. This is
> the reason I rarely respond any more to requests for information.

Look up "proprietary."


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
December 22, 2004 7:42:50 PM

Archived from groups: rec.audio.pro (More info?)

In article <10sis55dntbkq64@corp.supernews.com> williams@nwlink.com writes:

> Which is why, when asking for advice, you should give all the details. This is
> the reason I rarely respond any more to requests for information.

I think that "driving a tweeter to full power at 40 kHz" is clear
enough, even though the actual appliction is still cloaked in mystery.
If he told us the application and we didn't have the answer he was
looking for (which seems plain enough), the on-line "thing" is usualy
to try to tell him why he doesn't need it. It happens all the time.

That's not helpful either.



--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
December 22, 2004 7:42:51 PM

Archived from groups: rec.audio.pro (More info?)

>> Which is why, when asking for advice, you should give all the details.
>> This is the reason I rarely respond any more to requests for information.

> I think that "driving a tweeter to full power at 40 kHz" is clear
> enough, even though the actual appliction is still cloaked in mystery.
> If he told us the application and we didn't have the answer he was
> looking for (which seems plain enough), the on-line "thing" is usualy
> to try to tell him why he doesn't need it. It happens all the time.

> That's not helpful either.

You're right. I misinterpreted what he wrote.
Anonymous
December 22, 2004 8:47:35 PM

Archived from groups: rec.audio.pro (More info?)

"Neil Henderson"


** It pains me to think that perfectly good air is constantly being wasted
by this cretin.






............. Phil
December 22, 2004 10:28:10 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:32uh26F3ps9ogU1@individual.net...

At the risk of being flamed, I found the following rather interesting.

> ** There is no such application - the post was a troll

That may be, but do you have actual proof, besides the O.P.'s utter lack of
revealing the objective?

> Presuming an bullshitting are the only things this featherless squawker
> can do.

You contradicted you're self Phil, "Presuming" is something you just did, as
you see above.

> ............... Phil
>

Not that i'm bringing this into a religious debate, but this season is
pretty hectic as it is. Now, I dont know about you guys, but I'm taking it
easy, and not bring up my blood pressure for someone I dont even know.

Jim
December 22, 2004 11:11:31 PM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:32uif3F3prbqgU1@individual.net...

> ** Go choke on your damn turkey.
>
>
>
>
>
> ............ Phil
>
>

For X-mas, I prefer Ham. Thanks for the offer, though.

Jim
Anonymous
December 22, 2004 11:46:50 PM

Archived from groups: rec.audio.pro (More info?)

"DeserTBoB" <desertb@rglobal.net> wrote in message news:0tjjs0dloh21n3d6mrs5ara448nchb7nb9@4ax.com...
> On Wed, 22 Dec 2004 07:29:58 GMT, "David Morgan \(MAMS\)"
> <mams@NOSPAm-a-m-s.com> wrote:
>
> >I have nothing to add... except some WD-40. <snip>
>
> Why not do the proper thing and add him to your kill file? Life's too
> short for psychiatric cases with Usenet access.


I leave him alone for the most part, and his posts are illogically
entertaining in an off-beat sort of way. Heck... every now and
then he makes sense, and I'd hate to miss those rare moments.

;-)

DM
Anonymous
December 23, 2004 1:20:25 AM

Archived from groups: rec.audio.pro (More info?)

Len Moskowitz <moskowit@panix.com> wrote:
>
>I know what my application is. Do you?

I have no clue. If it's a sonar application, contact me offline and I
will put you in touch with some people making big modular sonar amps.
Transformer-coupled with transformers that can't do low end but are
designed for 40 KC and up.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
December 23, 2004 3:48:26 AM

Archived from groups: rec.audio.pro (More info?)

On 21 Dec 2004 10:10:18 -0500, moskowit@panix.com (Len Moskowitz)
wrote:

>Now that we've found those supertweeters from Scan Speak, Vifa and
>Townshend, we need an amp to drive 'em.
>
>Most of the pro audio and audiophile amps are only specified up to 20
>KHz though in magazine (e.g., Stereophile) reviews some of them measure
>well to beyond 40 KHz. Bryston, Parasound, Halcro and Aragon are among
>these. Some have their -3dB points at beyond 100 KHz.
>
>Might someone have a recommendation for an amp that's stable, reasonably
>powerful, and that can drive a 4 Ohm load at 40 KHz?

Do you REALLY need to? The fact that someone finds it advantageous
to advertise tweeters handling this sort of range doesn't mean you
have any sources offering these frequencies, or ears capable of
hearing them.

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
December 23, 2004 12:24:29 PM

Archived from groups: rec.audio.pro (More info?)

What is your problem?
Geeeze!
Anonymous
December 23, 2004 12:27:50 PM

Archived from groups: rec.audio.pro (More info?)

Chris Hornbeck <chrishornbeckremovethis@att.net> wrote:

>If you're really intending to drive a single dome tweeter, none
>of this will matter, because the tweeter's RMS dissipation will be
>about three watts in a cold room.

It'll likely be an array of transducers so we'll have better power
handling.

>But you're apparently working on something more interesting, so
>.....maybe one of the larger Adcom MOSFET-based hi-fi amplifiers?
>I've tested a 5503 to full rails into a capacitive load without
>drama. Can you specify the load?

Not quite yet. We'll have a look at the Adcoms. Thanks!


--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 23, 2004 12:31:11 PM

Archived from groups: rec.audio.pro (More info?)

Mike Rivers <mrivers@d-and-d.com> wrote:

>You should know by now that being *helpful* is against Phil's nature.
>He's only argumentive. If he can't argue with what you said, he'll
>imply that you said something else that he CAN (and does) argue about.
>Then he'll call you names.
>
>I've figured him out. He brings a little cheer to this sometimes dull
>newsgroup.

Ah, now I remember -- he's the fellow for whom we signed a "Get Well"
card at the AES dinner. Didn't know who he was at the time...



--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 23, 2004 12:41:15 PM

Archived from groups: rec.audio.pro (More info?)

Laurence Payne <l@laurenceDELETEpayne.freeserve.co.uk> wrote:

>>Might someone have a recommendation for an amp that's stable, reasonably
>>powerful, and that can drive a 4 Ohm load at 40 KHz?
>
>Do you REALLY need to? The fact that someone finds it advantageous
>to advertise tweeters handling this sort of range doesn't mean you
>have any sources offering these frequencies, or ears capable of
>hearing them.

The "ears" are electronics rather than human and the sound source is not
music.

Thanks to all for the assistance.

--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 23, 2004 2:06:49 PM

Archived from groups: rec.audio.pro (More info?)

"DeserTBoB"

> Why not do the proper thing and add him to your kill file?



** Same old Tosser Bob - another usenet Nazi with not a brain cell in
sight.




.............. Phil
Anonymous
December 23, 2004 3:51:32 PM

Archived from groups: rec.audio.pro (More info?)

"Bob Cain"

>
> William Sommerwerck wrote:
>>>>You have made a series of alarmingly false assumptions.
>>
>>
>>>I know what my application is. Do you?
>>
>>
>> Which is why, when asking for advice, you should give all the details.
>> This is
>> the reason I rarely respond any more to requests for information.
>
> Look up "proprietary."
>



** Go look up: "101 Dumb Excuses Used by Know Nothing TROLLS " - by
Bob Cain


You wrote the damn book !!!!





................ Phil
Anonymous
December 23, 2004 3:51:33 PM

Archived from groups: rec.audio.pro (More info?)

Thanks! How'd you know it was my birthday?

Chris Hornbeck
" ** Go choke on your damn turkey."
Anonymous
December 23, 2004 3:51:33 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison wrote:

> ............... Phil
>

Stop posting on usenet.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
December 23, 2004 3:51:34 PM

Archived from groups: rec.audio.pro (More info?)

On Wed, 22 Dec 2004 21:10:51 -0800, Bob Cain
<arcane@arcanemethods.com> wrote:

>Stop posting on usenet.

OTOH, and since I have only ten local minutes of birthday left
to be foolish, maybe....

I dunno, but shouldn't we honor the tradition of folks who
selflessly deflected the royal anger and misdirected the popular
attention from other matters?

The guy could get good high paying (with benefits!) work here
in America doing hate radio. Just a thought.

Chris Hornbeck
Anonymous
December 23, 2004 5:16:36 PM

Archived from groups: rec.audio.pro (More info?)

And a happy holiday to you too, Phil

Tom

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:32uggkF3o7rprU1@individual.net...
>
> "DeserTBoB"
>
> > Why not do the proper thing and add him to your kill file?
>
>
>
> ** Same old Tosser Bob - another usenet Nazi with not a brain cell in
> sight.
>
>
>
>
> ............. Phil
>
>
>
>
Anonymous
December 23, 2004 5:44:11 PM

Archived from groups: rec.audio.pro (More info?)

"Scott Dorsey"
> Len Moskowitz
>>
>>I know what my application is. Do you?
>
> I have no clue. If it's a sonar application, contact me offline and I
> will put you in touch with some people making big modular sonar amps.
> Transformer-coupled with transformers that can't do low end but are
> designed for 40 KC and up.


** About 10 years ago, the Australian Navy bought an 800 wpc audio amp for
testing SONAR transducers in their test lab in Sydney. The amp ( an M6,
IIRC) was one made using 12 Hitachi TO3 mosfets per channel by the German
company "Hertz " for general SR use.

The Navy needed its full power from 3 kHz up to 30 kHz - and part power
to 120 kHz for some transducers.

However, the Navy lab dudes kept blowing it up by shorting the output of
the amp to the input ground with their all metal, jack plug patch bay (
!!!!!) The Hertz was not built for such abuse and this event ripped through
the fine input PCB tracks and components like a bomb. As a cure, I fitted a
2.2 ohm resistor in series with the input ground and bypassed that resistor
with a 25 amp bridge rectifier wired as reverse parallel diodes to the main
PSU ground - this made the amp pretty much " Navy Proof ".

The Hertz was a rare example of an audio power amp that did not smoke the
zobel resistors at high continuous powers and frequencies.




............... Phil
Anonymous
December 23, 2004 5:44:12 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison <philallison@tpg.com.au> wrote:

>** About 10 years ago, the Australian Navy bought an 800 wpc audio amp for
>testing SONAR transducers in their test lab in Sydney. The amp ( an M6,
>IIRC) was one made using 12 Hitachi TO3 mosfets per channel by the German
>company "Hertz " for general SR use.
>
>The Navy needed its full power from 3 kHz up to 30 kHz - and part power
>to 120 kHz for some transducers.
>
> However, the Navy lab dudes kept blowing it up by shorting the output of
>the amp to the input ground with their all metal, jack plug patch bay (
>!!!!!) The Hertz was not built for such abuse and this event ripped through
>the fine input PCB tracks and components like a bomb. As a cure, I fitted a
>2.2 ohm resistor in series with the input ground and bypassed that resistor
>with a 25 amp bridge rectifier wired as reverse parallel diodes to the main
>PSU ground - this made the amp pretty much " Navy Proof ".
>
>The Hertz was a rare example of an audio power amp that did not smoke the
>zobel resistors at high continuous powers and frequencies.

Well, thanks Phil. That information was much appreciated!

--
Len Moskowitz PDAudio, Binaural Mics, Cables, DPA, M-Audio
Core Sound http://www.stealthmicrophones.com
Teaneck, New Jersey USA http://www.core-sound.com
moskowit@core-sound.com Tel: 201-801-0812, FAX: 201-801-0912
Anonymous
December 23, 2004 5:44:55 PM

Archived from groups: rec.audio.pro (More info?)

Scott Dorsey wrote:
>
> Len Moskowitz <moskowit@panix.com> wrote:
> >
> >I know what my application is. Do you?
>
> I have no clue. If it's a sonar application, contact me offline and I
> will put you in touch with some people making big modular sonar amps.
> Transformer-coupled with transformers that can't do low end but are
> designed for 40 KC and up.

I think Len is going to have to tell us the real application for this
amp. A 200kHz sonar amp isn't that different from a standard audio amp
but it is different enough to make a standard amp be of little use in
this application.

Cheers.

James.
Anonymous
December 23, 2004 6:51:10 PM

Archived from groups: rec.audio.pro (More info?)

On Wed, 22 Dec 2004 20:46:50 GMT, "David Morgan \(MAMS\)"
<mams@NOSPAm-a-m-s.com> wrote:

>
>"DeserTBoB" <desertb@rglobal.net> wrote in message news:0tjjs0dloh21n3d6mrs5ara448nchb7nb9@4ax.com...
>> On Wed, 22 Dec 2004 07:29:58 GMT, "David Morgan \(MAMS\)"
>> <mams@NOSPAm-a-m-s.com> wrote:
>>
>> >I have nothing to add... except some WD-40. <snip>
>>
>> Why not do the proper thing and add him to your kill file? Life's too
>> short for psychiatric cases with Usenet access.
>
>
>I leave him alone for the most part, and his posts are illogically
>entertaining in an off-beat sort of way. Heck... every now and
>then he makes sense, and I'd hate to miss those rare moments.
>
>;-)

Even a broken [analog] clock is right twice a day...

>DM
>

-----
http://mindspring.com/~benbradley
Anonymous
December 23, 2004 6:58:36 PM

Archived from groups: rec.audio.pro (More info?)

Mark wrote:

> What is your problem?


The consensus is "alcohol", I believe.
Anonymous
December 23, 2004 7:28:45 PM

Archived from groups: rec.audio.pro (More info?)

"His dimples, how merry!"

"Then laying a finger, aside of his nose,
And giving a nod, up the chimney he rose."

Chris Hornbeck
Anonymous
December 23, 2004 10:43:32 PM

Archived from groups: rec.audio.pro (More info?)

"Len Moskowitz" <moskowit@panix.com> wrote in message
news:cqalt7$p9c$1@panix3.panix.com...
>
> William Sommerwerck <williams@nwlink.com> wrote:
>
> >> Well, if you look at the frequency response, distortion, separation and
> >> power output specs on most of the low- and medium- priced amps that are
> >> out there, they look pretty bad at 40 KHz, especially when measuring at
> >> rated power. And then there's a question of simple stability.
> >
> >But you don't need full power at 40kHz, unless you're trying to deafen
> >bats.
>
> Sounds like an interesting application!
>
> In our application, we actually need full power.

So what "Full " level are the tweeters actually rated to at 40 kHz?
2 watts, 5 watts maybe :-)

TonyP.
Anonymous
December 23, 2004 10:46:07 PM

Archived from groups: rec.audio.pro (More info?)

"Len Moskowitz" <moskowit@panix.com> wrote in message
news:cqam45$oeu$1@panix3.panix.com...
>
> Phil Allison <philallison@tpg.com.au> wrote:
>
> >> Well, if you look at the frequency response, distortion, separation and
> >> power output specs on most of the low- and medium- priced amps that are
> >> out there, they look pretty bad at 40 KHz, especially when measuring at
> >> rated power.
> >
> >
> >** You do * NOT * need full rated power at 40 kHz to drive some wanky
> >tweeter.
>
> Oddly enough, we do.

What is the actual tweeter power rating then (not "system power").
*FAR* less than any amp I suspect!

TonyP.
Anonymous
December 23, 2004 10:48:01 PM

Archived from groups: rec.audio.pro (More info?)

"Len Moskowitz" <moskowit@panix.com> wrote in message
news:cqaq8d$mm8$1@panix1.panix.com...
> If you can recommend *any* amp that will put out 150 to 400 Watts at 4
> Ohms into a reactive impedance, and is essentially unconditionally
> stable at 40 KHz, it would help.

If you can name ANY tweeter that will handle 150 to 400 watts at 40 kHz,
that will help too.

TonyP.
!