My 1024W RMS CLASS A+ amplifier.

[Hartono]

really ? Happy b'day Owen !!! long live and prosperous !!!

[sreten]

Hi,

FWIW I advised a friend to get a Technics class AA amplifier because the technique does work, though it is expensive to implement, they
are good value second-hand, price does not reflect the new price.

Another way of getting lots of effective class A voltage swing
(does not have to be class A for the swing) is the correct use
of active amplifiers driving a multi-way speaker.

e.g. 3 100W amplifiers split 3-way can produce "900W" wide-band transients.

/sreten.

[richie00boy]

sreten, Technics Class A+ / New Class A and Class AA are totally different animals. I have two of their Class AA amps myself.

[sreten]

Hmmm.......

Said amplifier and Technics class AA, seem the Sandman principle.

Class A+ and new class A I've not heard of.

/sreten.

[richie00boy]

I believe the amp under discussion is not a Dr Sandman bridge, which is as you say referred to by Technics as 'their' Class AA.

[nikwal]

Yeah maybe it could be good if class B side is limited in frequency somewhat and class a too but the other way.. or does that mess up something else in hifi way??? hm maybe put a class D on one side..

Maaan cut thoose big coolers up at least once and put one on each side, unless you want to be able to hug them in a cold winter night or something.. yeah I must say they look very cool!!! but maan it seems stupid somewhat..

[GK]

Originally posted by nikwal
Yeah maybe it could be good if class B side is limited in frequency somewhat and class a too but the other way.. or does that mess up something else in hifi way??? hm maybe put a class D on one side..

Maaan cut thoose big coolers up at least once and put one on each side, unless you want to be able to hug them in a cold winter night or something.. yeah I must say they look very cool!!!

That doesn't make a lot of sense. If the bandwidth of the class B amplifier was limited relative to the class A stage the rails for the class A stage would not track the output at high frequencies.

Originally posted by nikwal
but maan it seems stupid somewhat..

If you say so.

[GK]

Originally posted by richie00boy
I believe the amp under discussion is not a Dr Sandman bridge, which is as you say referred to by Technics as 'their' Class AA.

Actually, the class AA concept is technically inferior to the A+ method; The class A+ method drives the speaker at all times entirely from a 100% class A output stage . The reason the class AA method was more successful is because the A+ method was still too expensive and impractical to implement in any domestic power amplifier rated at less than several hundred watts rms.

For my 512W+512W rms stereo amplifier, it's perfect.

[GK]

Originally posted by 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

LOL!

Actually, it only has a plain 4X35W CD player/radio.
I don't like a lot of audio noise in my cars......the hotted up V8 I built for the VK, exhaling towards 7 grand through it's 3" exhaust is music enough to my ears......

Cheers,
Glen

[GK]

Major design update:

After banging my head against the wall the last few nights, trying to work out the best way to layout all the power circuitry on my big heatsinks, I’ve decided to abandon the excessively complicated bridged topology and to take a route I’ve been contemplating for quite a while already.
On these long heatsinks, a single-ended topology will be much easier to implement.

Another benefit of going single-ended is that only one class-A power output module with floating supply rails will be required for each channel (instead of two).
This means that, for a given output power, the class-A dissipation is half that of the bridged design.

In other words, by going single-ended, I’m able to have twice the power output with the same idle dissipation of the bridged design.

My amplifier is now rated at 1kW rms (continuous sinewave power) into 4 ohms per channel.

So it’s now: “MY 2000W CLASS A+ AMPLIFIER”.

This will probably make the design a little more crazy in the eyes of some. I have upgraded the supply voltages to suit, and the required transformers are on order………

For now, a simplified block of a single channel appears below. Schematics will follow this weekend if I have time…………