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THE AM BULLETIN BOARD => Technical Forum => Topic started by: K6JEK on January 24, 2012, 08:22:56 PM



Title: What to do with 5000W of audio
Post by: K6JEK on January 24, 2012, 08:22:56 PM
I have an opportunity to acquire a used Crown 5000 for a bargain basement price.  It's rated at 5000 watts into 4 ohms.  What could I do with it?

http://www.crownaudio.com/amp_htm/xls.htm

PS Wow is it heavy.


Title: Re: What to do with 5000W of audio
Post by: flintstone mop on January 24, 2012, 09:11:41 PM
ya could do something like this.

http://www.youtube.com/watch?v=qxl5Vlc1rIA&feature=related



Title: Re: What to do with 5000W of audio
Post by: W2PFY on January 24, 2012, 10:55:57 PM
You could use it with a pole pig reversed connected to power a Tesla coil modulated with music. Think of the Sparks dancing to the music. Do not use Rap music under penalty of law!!


Title: Re: What to do with 5000W of audio
Post by: W4AAB on January 24, 2012, 11:00:16 PM
RAP= Retchedness Attempting Poetry.


Title: Re: What to do with 5000W of audio
Post by: W3LSN on January 24, 2012, 11:21:12 PM
I have an opportunity to acquire a used Crown 5000 for a bargain basement price.  It's rated at 5000 watts into 4 ohms.  What could I do with it?

http://www.crownaudio.com/amp_htm/xls.htm

PS Wow is it heavy.


If the power bandwidth is adequate, you can get yourself one of those FCC Part-5 Experimental Licenses and make it your final PA on the 136 kHz VLF band.

73, Jim
WA2AJM/3



Title: Re: What to do with 5000W of audio
Post by: Rob K2CU on January 25, 2012, 09:23:10 AM
based upon the output voltages, you might be able to directly power/modulate a class E transmitter.


Title: Re: What to do with 5000W of audio
Post by: W2VW on January 25, 2012, 11:04:33 AM
Didn't you build a linear amp with multiple 4-125s?

Set it up for class C hi hi fb level mudulation.

Grab an Antek toroid xfmr. See Stu's excellent advice somewhere on here.

In 1993 I had a BC-610 with a 3-500z hacked into the final modulated by a Crest 4001. Used 1/2 of a T-368 plate xfmr for mod iron. (110/6336CT) Fed the B+ through a bunch of PS chokes in series.

It was JSed together just to see if it would work. Everything was in a very small shack.

The only guy I worked with that death trap was WB3HUZ. Wonder what ever happened to that guy.


Title: Re: What to do with 5000W of audio
Post by: WA1GFZ on January 25, 2012, 11:36:02 AM
Pink Floyd


Title: Re: What to do with 5000W of audio
Post by: K6JEK on January 25, 2012, 02:46:11 PM
All excellent suggestions but I have to weigh the value of the application against the weight of the object, 75 pounds including power cord and dust.

I had been thinking of a modulator for a big class E but the Pink Floyd suggestion is intriguing. I stumbled on the speakers from the original Fillmore West in a warehouse out here. Hook em up and turn that baby on.

Money
It's a gas
Grab that cash with both hands and make a stash


7/8 or is it 7/4

I could combine the thoughts. Build a big Class E and play Pink Floyd on 3885, drive everyone nuts. Just kidding, just kidding.


Title: Re: What to do with 5000W of audio
Post by: KM1H on January 25, 2012, 02:58:13 PM
Hmmm, I have the perfect mod iron (7400W) but the cost of a step up transformer and shipping that beast would be a slight negative ???

Carl


Title: Re: What to do with 5000W of audio
Post by: K5WLF on January 25, 2012, 03:00:58 PM

... I stumbled on the speakers from the original Fillmore West in a warehouse out here. Hook em up and turn that baby on. ...


Altec-Lansing A1-XXs X 4 (at least) if I recall. They had ladders up the front of them so the techs could service the multi-cellular HF horns. The only time I was in there, sitting (on the floor) against the back wall, where I could feel the bass and the music was right at threshold of pain -- there was a long-haired guy up one of the ladders with his head right up against one of the horns. He was into the music, took security about 15 minutes to get him down from there. I wonder if he could ever hear again.


Title: Re: What to do with 5000W of audio
Post by: k4kyv on January 25, 2012, 03:08:31 PM
You might need a  step-up  transformer to make it work, but drive two deep ground rods as far apart as your property allows, then feed the audio between them.  Supposedly some hams communicated by this method during the WWII shut-down.  I recall an article about it titled "Radio through the ground".  They claimed that with 20 watts or so, and good enough ground rods far enough apart, they could communicate over a mile away.  The receiver consisted of two similar ground rods at the distant location, with headphones wired between them.

If you could get several hundred feet of separation, and maybe use a couple of steel well casings to serve as the ground rods, 5 kw of audio might be audible tens of miles away. For the receiver, feed the output through an amplifier (with a good 60~/120~ filter at the input). Who knows how far you could work?

Ground loops for miles around might pick up music intermodulated with 60~ hum. You might even achieve WALT (Worked All Landline Telephones). ;D


Title: Re: What to do with 5000W of audio
Post by: W1RKW on January 25, 2012, 04:17:57 PM
You could use it as a spot welder and help Mike W8BAC with his battery project  ;) ;)


Title: Re: What to do with 5000W of audio
Post by: Carl WA1KPD on January 25, 2012, 04:43:21 PM
You might need a  step-up  transformer to make it work, but drive two deep ground rods as far apart as your property allows, then feed the audio between them.  S

I can see all the worms and moles coming out of the ground now for miles around.


Title: Re: What to do with 5000W of audio
Post by: Detroit47 on January 25, 2012, 04:50:43 PM
ya could do something like this.

http://www.youtube.com/watch?v=qxl5Vlc1rIA&feature=related



Fred is that your car?


Title: Re: What to do with 5000W of audio
Post by: ke7trp on January 25, 2012, 05:49:42 PM
Set your audio gen to 60HZ.  Wire up your Drill to the output of the amp and amaze your friends by drilling some holes with the drill.
C


Title: Re: What to do with 5000W of audio
Post by: WD5JKO on January 25, 2012, 06:12:08 PM


I have a Crown M600. For audio it is good for 750W 1Khz @ 8 ohms or 1340W at 4 ohms. This was DC coupled, and rated for +/- 100V output at up to +/- 20 amps. It could be used like an op-amp. One application might be as a power supply for a Class E RF deck. Set the output at 40V to set the carrier level, and then modulate the DC reference input such that the AC swing would bring the peak output to 100v and that I believe would represent 150% positive modulation.

Maybe this newer 5K Crown is also DC coupled, and has higher +/- DC voltage capability than my M600 does.

Jim
WD5JKO


Title: Re: What to do with 5000W of audio
Post by: k6jca on January 25, 2012, 10:01:45 PM
You might need a  step-up  transformer to make it work, but drive two deep ground rods as far apart as your property allows, then feed the audio between them. 

I saw something similar to this in Electronic Design (or was it EDN?) years ago.  It goes like this...

1.  Connect a signal generator to the input of amplifier (I think the original design used a 555).
2.  Connect the output to mechanical transducer driven into the ground.
3.  Turn on generator and lower frequency to the Earth's resonant frequency.
4.  Apply signal until Earth is destroyed.

Surprisingly straightforward.  I'm surprised it hasn't already been done.

- Jeff, k6jca


Title: Re: What to do with 5000W of audio
Post by: KB2WIG on January 25, 2012, 10:31:37 PM
"there was a long-haired guy up one of the ladders with his head right up against one of the horns."

Moth to the flame.


klc


Title: Re: What to do with 5000W of audio
Post by: WBear2GCR on January 26, 2012, 10:06:27 AM


Bridged it alleges 5kw into 4 ohms...

But it is really a 1.1kW amp each channel into 8 ohms.

Still not bad power. But I seem to recall that these newer Crown amps have a bad habit of letting the magic smoke out. I can check with a group of about a hundred top pro repair guys if ur interested to know for sure.

But it's a nice amp, at 75lbs, not too bad...

If it's not too expensive, I'd get it... its use will become apparent over time.

You can run ur speakers with it, it won't clip... :D
(actually that makes an audible difference)

                     _-_-bear


Title: Re: What to do with 5000W of audio
Post by: flintstone mop on January 26, 2012, 05:02:09 PM
ya could do something like this.

http://www.youtube.com/watch?v=qxl5Vlc1rIA&feature=related



Fred is that your car?

ahhhhhhhh yahhhhhh


Title: Re: What to do with 5000W of audio
Post by: Steve - K4HX on January 26, 2012, 05:37:28 PM
"there was a long-haired guy   retard up one of the ladders with his head right up against one of the horns."


There, fixed it.


Title: Re: What to do with 5000W of audio
Post by: K5WLF on January 26, 2012, 08:58:21 PM
"there was a long-haired guy   retard up one of the ladders with his head right up against one of the horns."


There, fixed it.

It all seemed pretty retarded to me. I grew up a country music guy and still am. In high school I wore cowboy boots and pearl-snap shirts when the rest of the guys were wearing Beatle boots and Nehru jackets. I ended up at the Fillmore because one of my college friends wanted to check it out. Left to my own devices, I'd have been at a country bar. Best part of the whole evening was the Altec A1-XXs. I'd never seen a set of them in person before.


Title: Re: What to do with 5000W of audio
Post by: w4bfs on January 26, 2012, 09:54:59 PM
hello test ....w3duq upside down amp POWERED by a crown 5000 amp ..... watch the lights dim ......


Title: Re: What to do with 5000W of audio
Post by: Opcom on January 26, 2012, 11:22:31 PM
ya could do something like this.

http://www.youtube.com/watch?v=qxl5Vlc1rIA&feature=related



retarded and defective


Title: Re: What to do with 5000W of audio
Post by: AC0TX on January 26, 2012, 11:29:58 PM
Feed 400 Hz into that thing
Use it to power  any 400Hz gear


Title: Re: What to do with 5000W of audio
Post by: Opcom on January 27, 2012, 02:18:42 AM
400Hz gear? that's the best use yet. Home subwoofer amp is also good, but the speakers to make that a reality are something else as well.


Title: Re: What to do with 5000W of audio
Post by: KB2WIG on January 27, 2012, 11:39:44 AM
A square wave generator, starter motor selenoid, some 2X4s  and you've got the makins of a  nice shake  table.


klc


Title: Re: What to do with 5000W of audio
Post by: W2PFY on January 27, 2012, 12:19:36 PM
Quote
I wore cowboy boots and pearl-snap shirts

I hope you had a bunny buckle too ;D ;D
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands