300W 'modulated bias' cascode Killer Amp

amplifierguru · 10th November 2005, 11:27 PM

Here is the first pic of the 300W version of the simple Killer Amp.

The complementary differentials are cascoded allowing the same Ft > 200MHz, Hfe > 450, 65V transistors to be used for inputs diffl's and driver/buffer with 4 pair of matched IRF complementary MOSFETs.

The cascode BJTs are biassed from a divider in the following driver which is modulated with the driver signal out of phase with the input/feedback signal to the differentials. This reduces THD by 2 to 3 times over a standard biassing arrangement.

I stll haven't bought that better camera.

Cheers,
Greg

Workhorse · 11th November 2005, 03:37 AM

Guru , I think a schematic would be a better option than this photograph

Cheers
K a n w a r

sam9 · 11th November 2005, 04:31 AM

Ditto. Your digital camera has even crappier resolution my mine.

amplifierguru · 11th November 2005, 05:04 AM

Hi Kanwar, Sam 9.

OK,OK I'm shopping for a camera tomorrow! They let me out on day release Saturdays.

Here's the topology.

http://members.dodo.com.au/~gregball/guru_007.htm

Full schematics come with the kit.

Cheers,
Greg

Workhorse · 11th November 2005, 05:15 AM

Ok Greg,

Purchase a digital Camera with "OPTICAL ZOOM" only , donot take digital zoom instead of it, because optical zoom is much clearer than digital zoom, after all optical zoom is another form of image amplification....

regards,
K a n w a r

peranders · 11th November 2005, 05:52 AM

Just wondering, but don't you get a rather high output impedenace when you have drain out?

The distortion is reduced you say by 2-3 times, from what?

Workhorse · 11th November 2005, 06:04 AM

This line made me laugh out of Hell......

"You work for small outfits, and can do weird stuff because there is no one there to keep you under control"

Peranders, Is this really from one of the 29 commandents of Jocko Homo......HAHAHAHAHAAAA

What:?

Lots of Signatures PA

peranders · 11th November 2005, 06:16 AM

Quote:

Originally posted by Workhorse
Peranders, Is this really from one of the 29 commandents of Jocko Homo......HAHAHAHAHAAAA

Word by word by the Great One from Texas. Nothing added or removed.

amplifierguru · 11th November 2005, 06:37 AM

HaHaHa

"You work for small outfits, and can do weird stuff because there is no one there to keep you under control"

I resemble that remark.

Peranders,

THD is 2 to 3 times lower than with a conventional fixed bias cascode. More to come.

The Zout should prove even lower than the smaller 2 o utput pair Killer Amp as the doubled output stage will have 2 x transconductance so 2 x voltage gain, so 2 x NFB, so 2 x lower Zout !

Cheers,
Greg

peranders · 11th November 2005, 06:45 AM

Have you verified your claims about the dist? From what to what? 0.0046 to 0.0023% or 0.3 to 0.1%?

11th November 2005, 03:37 AM	#2
Workhorse diyAudio Member Join Date: Dec 2004	Guru , I think a schematic would be a better option than this photograph Cheers K a n w a r __________________ It's a fruitless endeavor to try and educate a fool that rejoices in ignorance

11th November 2005, 05:15 AM	#5
Workhorse diyAudio Member Join Date: Dec 2004	Ok Greg, Purchase a digital Camera with "OPTICAL ZOOM" only , donot take digital zoom instead of it, because optical zoom is much clearer than digital zoom, after all optical zoom is another form of image amplification.... regards, K a n w a r __________________ It's a fruitless endeavor to try and educate a fool that rejoices in ignorance

11th November 2005, 05:52 AM	#6
peranders Electrons are yellow and more is better! diyAudio Member Join Date: Apr 2002 Location: Göteborg, Sweden Blog Entries: 4	Just wondering, but don't you get a rather high output impedenace when you have drain out? The distortion is reduced you say by 2-3 times, from what? __________________ /Per-Anders (my first name) or P-A as my friends call me

11th November 2005, 06:04 AM	#7
Workhorse diyAudio Member Join Date: Dec 2004	This line made me laugh out of Hell...... "You work for small outfits, and can do weird stuff because there is no one there to keep you under control" Peranders, Is this really from one of the 29 commandents of Jocko Homo......HAHAHAHAHAAAA What:? Lots of Signatures PA __________________ It's a fruitless endeavor to try and educate a fool that rejoices in ignorance

11th November 2005, 06:45 AM	#10
peranders Electrons are yellow and more is better! diyAudio Member Join Date: Apr 2002 Location: Göteborg, Sweden Blog Entries: 4	Have you verified your claims about the dist? From what to what? 0.0046 to 0.0023% or 0.3 to 0.1%? __________________ /Per-Anders (my first name) or P-A as my friends call me


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11th November 2005, 04:31 AM	#3
sam9 diyAudio Member Join Date: Jun 2002 Location: Left Coast	Ditto. Your digital camera has even crappier resolution my mine.

11th November 2005, 05:04 AM	#4
amplifierguru Account Disabled Join Date: Aug 2004 Location: Earth	Hi Kanwar, Sam 9. OK,OK I'm shopping for a camera tomorrow! They let me out on day release Saturdays. Here's the topology. http://members.dodo.com.au/~gregball/guru_007.htm Full schematics come with the kit. Cheers, Greg

11th November 2005, 06:37 AM	#9
amplifierguru Account Disabled Join Date: Aug 2004 Location: Earth	HaHaHa "You work for small outfits, and can do weird stuff because there is no one there to keep you under control" I resemble that remark. Peranders, THD is 2 to 3 times lower than with a conventional fixed bias cascode. More to come. The Zout should prove even lower than the smaller 2 o utput pair Killer Amp as the doubled output stage will have 2 x transconductance so 2 x voltage gain, so 2 x NFB, so 2 x lower Zout ! Cheers, Greg

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