1kW MOSFET amplifier

[mgoedeke]

Kilowatt, I mentioned the LAB horn a while ago, and this would get you serious output at low distortion. You could even still use your 900W modules to power each horn. If used indoors, you’ll “only” need 2 of these monsters per side and it will give you decent performance to below 30 Hz (read up at http://www.prosoundweb.com/community...rd=3&id=143250). If you’re hell-bent on building a 7200W amplifier ( and I applaud your courage), the horn reaches Xmax at about 300W @ 30 Hz (where a stack of 6 develops around 150 dB in half space), but I figure these will easily soak up transients of 1000W cleanly because excursion drops off dramatically above 30 Hz. Thermal power handling should be around 1200W per horn.

Another benefit of the horn, is that it presents a benign load to the amplifier and might help with the current drain situation. I would bet, that very few direct radiator systems would come close to such a beast and you get less distortion and far less compression for the same output (and investment in $$$). Only problem might be to build/move the LAB horns, though it should still be ok.

Wish you well on your ways

Martin Goedeke

[Kilowatt]

Hey guys, I haven't posted in awhile, I'm about 1500 miles from my house right now on vacation in Arkansas. I'll be back next week.

Jason, I am going to have efficient speakers, so it will have LOTS of SPL. You can go louder with 7200W than 100W if you use the most efficient speakers for both (duh). And all 7200W of it will hopefully have no more than .01%THD, a design with similar topology gets .0038% at like 120W into 4 or 8 (I forgot which) ohms. The reason why I'm doing it has been covered, it's not made to pump 150dB into your ears, it's made for distance. I have yet to start getting deeply into the design, but I will later this summer. Anthony never replied to me when I emailed him before either.

Martin, where can I get LAB horns? How much are they, can I affored them? Also remember I want 12 ohms/module. Will they even work for me? (I hope they do! )

Thanks

[Kilowatt]

Having nothing better to do (I can't work on my Leach amp until I can get some small drill bits), I have come up with a possible topology for my 900W amp modules, which I will officially call the "Kilowatt Amp." I haven't designed any amps so far, so don't expect it to be the finished product yet. Any ideas are welcome.

The input stage is almost the same as Slone's "figure 11.14," but using a more stable current source for the diff amps. The OPS is configured the best I could figure using Prof. Leach's series design with a CF MOSFET stage. I haven't calculated any component values yet, but I'll work on that soon and post an updated schematic. Right now I just want to know what people think of the topology.

I can't get it all to fit in the 100,000 byte limit, so I'll have to break it up. I've always had a lot of trouble trying to get things to fit. Is there a better way?

[Kilowatt]

2

[Kilowatt]

3

[Kilowatt]

4

Again, I apologize for the inconvenient method of posting my schematic, but I don't know a better way to do it.

[AudioFreak]

Kilowatt,
I hope this helps.

Here's what it looks like in one piece.

[Kilowatt]

How'd ya do it?

[AudioFreak]

paint shop pro 7

I glued them all back together, resized the image then saved as gif because it's a better format for schematics. 10 minutes work.

[Kilowatt]

Never mind, I see it's a GIF file.