series regulated power supply with feedback for Nelson Amplifier

[muddasirwaheedmalik]

hi,
Can any one give any schematic for series regulated power supply around 30 V on rail with 20-30Amp capability.

Objective: an ultimate Single Ended Class A amplifer.

Items at hand: Heat sinks (for regulator and recitifers) 8 incx8 inch real good,
4x 300Amp Hitachi diodes for rectification, 2 x1DI500-030 , 3000W PD, 500 A darlington BJT for intended rectifier use.

Amp design and wattage not decided yet. around 100-200W Pure Class A.

Power consumption and inefficiency is not a consideration.

Any design with simple series BJT with op-amp feed back. Regards

 

[AndrewT]

Why do you want a feedback style of regulated supply?
Why don't you adopt a non feedback style of regulated supply as described in detail in the PASS website?

 

[muddasirwaheedmalik]

Andrew Feedback type would provide better regulation, hence the objective of preventing sagging of rail voltages at greater current loads .
regards

 

[muddasirwaheedmalik]

data sheets

just for information , this is the BJT module which has prompted me to go fully regulated rail voltage for a constant bias Class A amp. regards

 

[muddasirwaheedmalik]

plus i have a pair of 2 KVA 220v:24+24 volt EI core transformers to use as mains.

 

[Boscoe]

How many channels is this for? 2KVA and 2500W BJTs are a bit extreme aren't for two channels?

 

[muddasirwaheedmalik]

Agreed. I have two 2500W BJT which i salvaged from a used UPS station costed me USD 15 each. hence the reason for already available devices at hand.

Its for two channel at the moment, i may upgrade to 4 channels in future for bi amping

As i want to least stress each active component of my system hence i assume i would not be using no more than 800 VA of each BJT for very safe , reliable and linear operation.

 

[muddasirwaheedmalik]

Plus if i want 100 W class A fixed bias amplifier i assume i will be constantly using at least 400 watts of load from each supplt.

 

[muddasirwaheedmalik]

For Son of Zen , 25W of output require a 1 KVA transformer.
for 20W output we need at least a continous 200W disspiation in resistors alone!
So for around 50W continours SE nothing less than 2 KVA will work and 2500W Pd power BJT doesnot seem too big ????

 

[Boscoe]

That's completed ridiculous and a waste of time. Speakers need a lot of power for dynamic peaks in the music we listen to. A 20W amplifier will clip a lot with properly recorded music. You may not recognise it at mediocre levels but it's there and will not sound as good as a more powerful amplifier. I recommend at least 150W/ch for proper listening. Proper high fidelity active speakers afoten use over 500W/ch total per channel on small 5" drivers.

SE also has very high distortion, very low output powers, are very big and extremely inefficient. To me there are no wins what so ever.

 

[muddasirwaheedmalik]

so no nelson pass????

 

[AndrewT]

No,
forget your feedback regulation.

 

[Boscoe]

so no nelson pass????

I don't like putting people off. If that's what you like then go for it! But if you want TRUE HIGH FIDELITY then there are much better ways of doing things!

 

[CBS240]

Here is a simple series voltage regulator circuit I've used. No noisy Zeners. Use the power Darlington as the emitter follower. Adjust the values as needed for the voltages you are using.

 

[Loudthud]

What are the devices 4091 and 4117?

Since the Idss of a J201 is about 1mA, the beta of the output transistors must be huge.