HP 6269B 0-40V@0-50A REGULATED DC POWER SUPPLY for DIY amplifier

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HP 6269B 0-40V@0-50A REGULATED DC POWER SUPPLY
Hi i have access to a pair of the fully regulated power supply unrepaired.
Its fully regulated excellent regulation for current and voltage
can be operated Constance current or constant current mode with complete protections.

I can get a pair for around 500 USD.
Is it a good option for diy power amplifier if i use them in series for +/- 40 Volts and it would have HUGE current capability , it weighs at 90 Ibs and i suppose making a diy power supply would cost way more than this.
Would remove the face plate with brushed aluminium with only meters in view hiding controls.

HP 6269B 0-40V@0-50A REGULATED DC POWER SUPPLY GUAR WKG | eBay

Advantage: self enclosed power supply will just add the power unit (separate clean box , dirty box) plus the advantage of visuals of current and voltage ??? very low ripple and noise.

Target. 1200W pull push amplifier into 8 ohm
 
500 USD damage or 1000 USD functional, seems a huge price.
Better to buy a separate 2kVA toroidal transformer, capacitors, rectifier bridge. In this case price even though reaches 400 ... 500USD, you get more performance power supply with toroidal transformer and is... a new PSU.
 
dear donpetru.
Both supplies are for 500USD total 250+250 and fully functional and unreparied.
Just wanted to use them as either constant current sinks for Class A single ended amplifier or dual set as constant voltage for class A pull push??? please advice would it give sonically and practiacally better output.
 
With a regular amp if you could swing the voltage from rail to rail you would have ((80*.3535)^2)/8 = 99.9698 W, bridged you would have ((160*.3535)^2)/8 = 399.8792 W. You could double the power into 4 ohms. Also you could power 10 channels of 100 W at 8 ohms.
 
dear donpetru.
Both supplies are for 500USD total 250+250 and fully functional and unreparied.
Just wanted to use them as either constant current sinks for Class A single ended amplifier or dual set as constant voltage for class A pull push??? please advice would it give sonically and practiacally better output.

I understand, but not enough only + /-40Vcc, you need a higher voltage to get 1200W / 8 Ohms. Look in the table below:
tabel2.PNG

and translate/read this article:
Surse de alimentare liniare pentru amplificatoare audio - calcul, teorie, concluzii - Surse de alimentare - Tehnium Azi - Home - Comunitatea Tehnium Azi
 
Oh got a big ambitious there. i meant a total dissipation of 1200W for class A operation for both channels. 600w per channel requires a voltage swing of 70V total peak. which is within +/-40v.
With 600W dissipation we can get around 10A per channel continous and 20A for 2 channels hence there will be much reserve still left in the 50A supply.

Now this discussion appart. i am seriously considering to put a single supply as a constant current sink say 5A in constant current mode and use 2SA5200 20 devices in parallel as output device. i.e. 250mA per device with peak 40V w.r.t ground would give a swing of 5A peak. so i would not be using dual rail. one power supply for each amplifier.

But my question is on comments regarding the sonic perfomance, voltage regulation, ripple etc of the said power supply is it a good idea?
 
I don't think you should "Now this discussion apart" so soon.
We are trying to figure out if these supplies are suitable for
your application.

"i meant a total dissipation of 1200W for class A operation for both channels.
600w per channel requires a voltage swing of 70V total peak"
I am not sure what "total peak" means ?
Class A does not require any voltage swing to dissipate.

"With 600W dissipation we can get around 10A per channel continous"
What and Where is this 10A are we are getting ?

"i am seriously considering to put a single supply as a constant current sink"
I don't think this type of power supply output works in 4 quadrants ?
To work as a constant current sink you would need a 2'nd supply
to furnish the current for the constant current sink.

D. Self suggests that Class A topologies can range from %12.5 to %50
efficiency. Could you please supply a quick schematic of your proposed
amplifier circuit.
 
oK. agreed its not much clear. so lets rewind it.

Only the positivie terminals are series pass regulators in the supply so the supplies cannot be used in series for positive and negative rails.

This means that each supply can only be used for sigle rail +40/ground.

Now each supply can be used as either constant voltage or constant current.

The ripple is extremely low and voltage and current regulation is extremely good from the specs.

So a single ended class A amplifier can be designed without much concern to reduce line hum and ripple inherent in single endded class A.

The single ended class A with resistance as current sink gives 12.5% efficiency with acitive current source it will give 25%.

So here is the agenda. use the power supply as a constant current source for 25% efficiency of class A amplifier.

With 40V on the rail the max current for 8 ohm is 5 ampere for one channel which is 10% of the rated capacity of the supply.

The voltage and current meters gives good visuals and short/OV/OC protections gives sufficient room if anything goes wrong with amp output stage.

This is the VTLK dirty and clean box approach with separate power supply you improve EMI and noise rejection.

Now with 5 ampere continous draw one can use 2.5 A max for class A single ended operation which gives 2.5*2.5*8=50W RMS power which would double in 4 ohm so for varying impedance and much reserve the supply has plently of reserve to provide extraordinary dynamics.

NOW the topology part. i have no idea right now . help solicited. i need simple minimilistic parts (BTW 2SC52OO are my favourite) and i plan to use 16 in parallel with 0.22 ohm vishay metal film resistors 25W (i have in stock) to give me 0.0135 ohm RE.

with 5 A continous in 16 devices would give around 312.5mA quiescent current in each device with sa 40*0.3125=12.5W dissipation in each device, so think Beta non linearities could be avoided.

Any suggestions/comments/links.criticisms and ideas area highly welcome.
regards
 
P.S

The reason for not going pull push. since its regulated on positive terminal i doubt series combination for +40/-40V would be possible.
finding matching complimentary 16 pairs per channel........real task
Added circuit complexity of pull ---push certainly a no go area for me.

Why single ended........warm lush sound,........ i own a cary 805 50W and it sounds beautiful.

wish any thing near that could be accomplished with solid state. OEM power supply.
regards
 
Just in.
Since the Op current is limited function in the supply. the bias correction cirucuit could be ignored.
No chance of thermal run away ....with increased temprature of output device the demand on Ic would increase due to reduced resitance CE but the current limiting function will hold back the IC. stablizing the Ic. So another advantage of constant current supply.
 
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