Can this be for real?!

DigitalJunkie · 6th June 2006, 09:58 AM

I was just going through some old files and clutter on my harddrive,and ran across this schematic for a 31KW Mosfet amp...

Is this thing for real?

kartino · 6th June 2006, 10:15 AM

Well, I did not check detailed ho amps works but the 'crude' wattage of amps are depend on how high your rails and how high your speaker impedance. Just simple ohm law V=I.R and P=V.I.

Because you don't mention your output impedance we don't know thw wattage, how many pairs mosfet needed and how many amps to feed the gates, basically whole amps

sreten · 6th June 2006, 12:43 PM

Hi,

simple answer is not really, there are far better ways of approaching
such power levels, e.g. multiple rail class G amplifers.

Though it seems it has +/- 180V rails and is bridged.

IMO there is totally not enough juice to drive
the gate capacitances of the output mosfets.

also see : http://sound.westhost.com/project117.htm

/sreten.

Tekko · 6th June 2006, 12:49 PM

Hahahahahahaha That is what i call a real heater.

I wonder who would want that extreme powers

As far as i know there is only a driver that takes max 5kW, the MTX JackHammer.

Jennice · 6th June 2006, 01:06 PM

Did someone say hearing loss?

Just the size and weight of the power supply alone is a scary thought. The idle power consumption must be of "Nelson Pass"'ish proportions

Jennice

janneman · 6th June 2006, 03:13 PM

It's grossly overdone. For a 180V supply, let's say the peak output voltage = 170V which is about 120V RMS. Double it for a bridge gives you 240V RMS in 8 ohms is about 7.2 kW. Puny.

Jan Didden

davidsrsb · 6th June 2006, 03:16 PM

I thought that the really high power stuff was all active crossover with switching amps for the bass/mid and the hf no problem as piezo horns are so efficient.

Mr. Triatic · 6th June 2006, 04:32 PM

well.. i recently did maintenance on a 100kW switchingmode amplifier 8-) (Solidstate with MosFets)

Tekko · 6th June 2006, 04:51 PM

100kW class d !?!?!? Your kidding

Mr. Triatic · 6th June 2006, 05:01 PM

nope.. imagine such an amp in your livingroom (it takes about that much place..) driving you 98dB hornspeakers... 8-)

6th June 2006, 12:49 PM	#4
Tekko diyAudio Member Join Date: Jan 2005	Hahahahahahaha That is what i call a real heater. I wonder who would want that extreme powers As far as i know there is only a driver that takes max 5kW, the MTX JackHammer. __________________ The point of life is to build atleast one audio amplifier before you die.

6th June 2006, 01:06 PM	#5
Jennice diyAudio Member Join Date: Jun 2003 Location: Planet Earth	Did someone say hearing loss? Just the size and weight of the power supply alone is a scary thought. The idle power consumption must be of "Nelson Pass"'ish proportions Jennice __________________ I get paid to break stuff. My g/f gets paid to play with children. Life is good.

6th June 2006, 03:13 PM	#6
janneman diyAudio Member Join Date: May 2002 Location: Where Germany, The Netherlands and Belgium meet Blog Entries: 6	It's grossly overdone. For a 180V supply, let's say the peak output voltage = 170V which is about 120V RMS. Double it for a bridge gives you 240V RMS in 8 ohms is about 7.2 kW. Puny. Jan Didden __________________ /Another new issue: Linear Audio Volume 3!

6th June 2006, 04:32 PM	#8
Mr. Triatic diyAudio Member Join Date: Feb 2002 Location: SWE EU	well.. i recently did maintenance on a 100kW switchingmode amplifier 8-) (Solidstate with MosFets) __________________ www.joddla.net/audio/

6th June 2006, 04:51 PM	#9
Tekko diyAudio Member Join Date: Jan 2005	100kW class d !?!?!? Your kidding __________________ The point of life is to build atleast one audio amplifier before you die.


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6th June 2006, 10:15 AM	#2
kartino diyAudio Member Join Date: Feb 2005 Location: Gunungkidul Indonesia	Well, I did not check detailed ho amps works but the 'crude' wattage of amps are depend on how high your rails and how high your speaker impedance. Just simple ohm law V=I.R and P=V.I. Because you don't mention your output impedance we don't know thw wattage, how many pairs mosfet needed and how many amps to feed the gates, basically whole amps

6th June 2006, 12:43 PM	#3
sreten diyAudio Member Join Date: Nov 2003 Location: Brighton UK	Hi, simple answer is not really, there are far better ways of approaching such power levels, e.g. multiple rail class G amplifers. Though it seems it has +/- 180V rails and is bridged. IMO there is totally not enough juice to drive the gate capacitances of the output mosfets. also see : http://sound.westhost.com/project117.htm /sreten.

6th June 2006, 03:16 PM	#7
davidsrsb diyAudio Member Join Date: Dec 2005 Location: Kuala Lumpur	I thought that the really high power stuff was all active crossover with switching amps for the bass/mid and the hf no problem as piezo horns are so efficient.

6th June 2006, 05:01 PM	#10
Mr. Triatic diyAudio Member Join Date: Feb 2002 Location: SWE EU	nope.. imagine such an amp in your livingroom (it takes about that much place..) driving you 98dB hornspeakers... 8-) __________________ www.joddla.net/audio/

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