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.
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.
sreten, Technics Class A+ / New Class A and Class AA are totally different animals. I have two of their Class AA amps myself.
Hmmm.......
Said amplifier and Technics class AA, seem the Sandman principle.
Class A+ and new class A I've not heard of.
🙂/sreten.
Said amplifier and Technics class AA, seem the Sandman principle.
Class A+ and new class A I've not heard of.
🙂/sreten.
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.
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..
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..
nikwal said:
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.
If you say so.
richie00boy said:
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.
Stuey said:
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
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…………
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…………
Attachments
Hartono said:
All up it will be a lot more than that. I've ordered four 200VA EI (split bobbin - better primary-secondary isolation than a toroid) transformers to provide the floating supplies for the class-A stages. These weigh 2.8kg each.
A pair of 2kV toroidal transformers supply the class B stages. I don’t know what these will weigh.
There are also various little transformers for ancillary stuff.
Incidentally, whilst finalising the transformer order and looking into available electrolytic capacitors, I have revised the amplifiers rated power/load impedance again 🙄
The amplifier is now going to be built to deliver 1000W rms per channel (continuous sinewave) into 2 ohms, not 4 ohms. This is much more sensible, as a pair of 4 ohms speakers (or even a quad of 8 ohm speakers) can be paralleled to make a 2 ohm load. Ever seen a 4 ohm 1kW speaker in a HiFi shop 🙂 ) ??
The 2 ohm rating also means that the class-B supply voltages can be kept well below +/-100V (1kW rms into 2ohms = 63.2V peak). Electrolytic filter capacitors for supply voltages below 100V are much cheaper and easier to obtain.
Phew. I’ll get back to the (final?😕 ) version schematics and PCB layouts now.
Cheers,
Glen
Hartono said:If you build it, probably you will be on world's class A hall of fame. 1000 watt class A
If????
Dude, I'm not going to make a BBQ out of those ridicuously expensive heatsinks! 🙂. The transormers are on the way, I've already got the one hundered 10,000uF 16V ELNA electrolytics for the filtering of the floating class-A power supplies..........
Stay tuned to this thread.......
Cheers,
Glen
Ouch
What will this thing be pulling out of the wall?
Your carbon footprint will be soooooo big and deep kids will be able to use it as a skatepark😱
What will this thing be pulling out of the wall?
Your carbon footprint will be soooooo big and deep kids will be able to use it as a skatepark😱
Wow, what an undertaking!
will be very impressive when finished, a feat of engineering and DIY!
Might look more like an old 70's super computer in the corner of the room instead of an amp though, except probably much hotter!
Hope you saved up some reserve cash to pay your power bills though, maybe you could use it for a kind of co-generation system during winter months 😀 .
Regards
Craig
will be very impressive when finished, a feat of engineering and DIY!
Might look more like an old 70's super computer in the corner of the room instead of an amp though, except probably much hotter!
Hope you saved up some reserve cash to pay your power bills though, maybe you could use it for a kind of co-generation system during winter months 😀 .
Regards
Craig
Re: Ouch
Might want to consider mains circuit breaker derating too.
20A@120V should (barely) power 2 channels.
If it were me, I'd run a new 240V circuit, with a minimum 10ga. wires.
Such an amp deserves a good power supply.
JRKO said:
Might want to consider mains circuit breaker derating too.
20A@120V should (barely) power 2 channels.
If it were me, I'd run a new 240V circuit, with a minimum 10ga. wires.
Such an amp deserves a good power supply.
Personally, I wouldn't want 3 phase as it would increase the hum frequency and make it more noticable.
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