My 1024W RMS CLASS A+ amplifier.

[GK]

Originally posted by MJL21193



Hi Glen,
A completely solid attachment of the two metals might result in bending with temperature change - similar to a bi-metal bar in a thermistat.
Something to consider.

I'm interested in your design, but would like to try it on a smaller scale. 1Kw/channel is a tad high for my purposes.

Keep up the good work.

Yes I know, this is a pain. Aluminium has an expansion coefficient that’s about 30% greater than that of copper.
I’m fooling around with the idea of using at thick sheet of copper, and building all the power output stages onto it as a sub assembly, which will be clamped to the aluminium heatsinks in favour of solid attachment.
Problem is that copper is very soft and malleable, so I’ll need a pretty thick sheet (say 8mm or so). I’m getting the prices for the copper next week. I’m a bit fearful of what I’m going to hear though, so the copper idea is still pending.

I may be getting a little too esoteric with the design here

[GK]

Originally posted by Gold_xyz

Hi

It excuses my ignorance but it would be pleasant to also see a block diagram of the whole amplifier.

Thanks.

Here you go:

http://users.picknowl.com.au/~glenk/2000W.HTM

[jacco vermeulen]

Originally posted by G.Kleinschmidt
http://users.picknowl.com.au/~glenk/CLASSB.HTM

Glen,

just curious, when will you be up for parole ?

[Upupa Epops]

Use for cooling this principle....

[GK]

Originally posted by jacco vermeulen


Glen,

just curious, when will you be up for parole ?

Huh?

Originally posted by Upupa Epops
Use for cooling this principle....

----------------------------------------------------------------------------------

PCB for the +/-80V regulator is done.........Now onto the input/VAS PCB.........



Ta-da!

[jacco vermeulen]

Originally posted by G.Kleinschmidt
Huh?

Another 256 Re's for the AB stage, makes a total of 496 you''ll be soldering.
I fail to see the advantage with such numbers involed, unless you'll spend a month in the slammer for masacring a kangaroo family.
What's the cost of a 1 watt metalfilmer in Bauxtralia ?

[darkfenriz]

Originally posted by G.Kleinschmidt

http://users.picknowl.com.au/~glenk/CLASSA.HTM (+new one)

Hi, I am not sure about short circuit protection circuit, together with Hawksford's circuit it will saturate protection transistors when short circuit happens IMO. This is contrary to typical output stages, where active protection has proper Vce.

[GK]

Originally posted by jacco vermeulen


Another 256 Re's for the AB stage, makes a total of 496 you''ll be soldering.
I fail to see the advantage with such numbers involed, unless you'll spend a month in the slammer for masacring a kangaroo family.
What's the cost of a 1 watt metalfilmer in Bauxtralia ?

I already metioned the advantage in a previous post. Perhaps you missed it.

[GK]

Originally posted by darkfenriz



Hi, I am not sure about short circuit protection circuit, together with Hawksford's circuit it will saturate protection transistors when short circuit happens IMO. This is contrary to typical output stages, where active protection has proper Vce.

No! The protection transistors (as well as the EC circuit transistors) do not saturate on current limit. At the current limit of 64A, the 'error voltage' between the output and the end of the 750 ohm resistor clamped by the protection transistors will be in excess of 2V. The protection transistors clamp this voltage to maintain a constant load current - just like in a normal output stage.
Since the protection transistors clamp the 'error voltage', the EC circuit is inhibited also.

Cheers,
Glen

[Upupa Epops]

Glen, look at " two pins " transistors, maybe something burn in your head...