My 1024W RMS CLASS A+ amplifier.

[GK]

Originally posted by teemuk
Those heatsinks are mighty big but I have doubts about their efficiency in the configuration you planned: See the vertically oriented fins loose their efficiency if they are too high since the air warms up in the "early stages" and convenction can't cool the rest of the sink. Are you going to make somekind of forced cooling scheme to that thing as well?

I have compensated for the loss in efficiency by over-specifying the size of the heatsinks. They are more that big enough, even in the vertical position. The amplifier is going to be a bridged design, so there are no less than 8 power output stages in total. The lower dissipating Class AB stages and the regulated power supplies will go towards the top of the heatsinks.

Originally posted by teemuk
Anyway, seems like an interesting project and I can imagine that the amplifier "column" will look pretty awesome.

Yes
I'm also building a dual trace signal monitoring oscilloscope (round CRT, green phosphor) which will be installed towards the top of the unit. The amplifier will have a gloss black front panel, several old fashioned (1940's) panel meters for montoring various things such as class A bias, supply voltages, etc, and lots of blue leds in chome bezels!


Cheers,
Glen

[Leolabs]

What is the size of the transformer???

[Bonsai]

Glen,

great project , but I am, as are a lot of other people, concerned about the global warming implications of your 1024W linear design.

Next time the lights dip in Tokyo mate, I'll be looking south in the general direction of oz!

cheers

[Cloth Ears]

Hi Glen,

How much did the 3 metre sink set you back?

[richie00boy]

Originally posted by G.Kleinschmidt
I'm sorry, but that is just baloney. The design is 100% class A. Perhaps you are confusing it with something else.

Anyone interested enough in learning more can read up on it by obtaining the reference here:

http://www.diyaudio.com/forums/showt...67#post1237267

One part of the design is 100% class-a yes. But if you actually follow the current path you will see it's return is through a class-b stage, making the class-a stage pointless. So you might as well just run the class-b part.

Unless of course I am confusing this design with something else as I couldn't download the PDF without paying for it.

[GK]

Originally posted by richie00boy


One part of the design is 100% class-a yes. But if you actually follow the current path you will see it's return is through a class-b stage, making the class-a stage pointless. So you might as well just run the class-b part.

Unless of course I am confusing this design with something else as I couldn't download the PDF without paying for it.

No, it doesn't make the class-A stage pointless at all. The class B amplifier drives the rail voltages for the class A stage. The class A stage drives the speaker. The fact that the return path is through the class-B stage hardly matter a jot.

The speaker is driven in 100% class A.

I suggest that you actually pay for the paper, which actually examines in detail the relevance of the class-B crossover irregularities on the power supply rails of the class-A output stage.

The crossover irregularities are attenuated at the speaker output dramatically and the tracking rails actually improve the linearity of the class-A output stage by effectively bootstrapping Vce. In my design, any minescule remnants of crossover distortion will be cast completely into oblivion by Hawksford Error Correction applied to each class-A output stage. And I'm also using heaps of global negative feedback.

[GK]

Originally posted by Leolabs
What is the size of the transformer???

Oh, there are lots of transformers and lots seperate rail supplies. I'll go through all this in the future with the circuit details.

Originally posted by Cloth Ears
Hi Glen,

How much did the 3 metre sink set you back?

About $780 + GST and freight.

Cheers,
Glen

[Stuey]

Hi Glen,

Man, if you plan a 1024W amp for home use, you must have at least a 10,000 watter in that V8 VK Commodore...

Cheers

Stuey

[Hartono]

those heatsink can make a nice barbie(BBQ) set. LOL

Hartono

[DoomPixie]

looks interesting (and expencive), will be keeping an eye on this one for sure! did i mention its my birthday today?
Owen