1000W tube amplifier

[Helmuth]

Philips EL6471 with QB3.5 750 as end tube. This a cool amp😎

YouTube - 1000W Amplifier Philips EL6471 at full power

YouTube - Philips EL6471 playing stereo part 3

power test glow QB3.5
YouTube - Philips EL6471 3,2 Kv on 250 Ma

more music
YouTube - 1kW Philips EL6471 Tube Amplifier from 1955 demonstrates its original sound - listen!

Enjoy

 

[mississippi]

Does somebody has a schematic diagram or a service doc. from this amplifier ?

 

[Hi_Q]

More info on the tube and a link to the data sheet pdf file (1.29M) here-

QY4-250

Heaters at 5V at 14A! Might be a task for an old PC power supply?
I have a couple of these tubes if anyone wants one for experimentation, nice bottles in Pyrex glass (I think) and lovely solid graphite anode.
Les

 

[Helmuth]

More info on the EL6471
Großverstärker EL6471 Radio Philips Radios -

 

[mississippi]

Nice photo's, but no service or schematic diagram of this amplifier.🙁

 

[Don Hills]

You call that an amp? Now these are amps...

Champ 1000 Watt Tube Amp

VTL - Reference Monoblocks

Amplifiers with valves

 

[kavermei]

What would you do with a schematic? Do you need that much power? Do you have 3-phase power in your living room?

FWIW, the schematic would be very predictable, too...

 

[mississippi]

Thanks for the links.

That I ask for the service doc and or schematic diagrams is because I collect all Philips valve amplifiers service doc's as a hobby.
This service doc or schema is almost the only one I do not have.

 

[kavermei]

ok, great! You collect the actual printed manuals or PDF files?

 

[banat]

Philips EL6471 Service Manual + Schematic(pdf) : http://83.117.57.34/nvhr/Philips_EL6471.pdf

 

[Helmuth]

Philips EL6471 Service Manual + Schematic(pdf) : http://83.117.57.34/nvhr/Philips_EL6471.pdf

Great Banat and in Dutch to. 🙂 Amazing straight forward is the design.

 

[banat]

This Philips EL6471 Power Amp is the smallest one , there is another two model with 10 and 20 KW of out. power .

Found in Philips EL6471 design two characteristic typical solution :

1) Use of three phase PSU ,which is typical for professional Audio power amps when input power consumption exceed 1 KW .

2) Use of two EL34 (triode strapped) DC coupled drivers for two QB3,5/750 output power tubes to obtain the best audio performance,output power efficiency and rock solid output power stage stability .

Best Regards

 

[mississippi]

ok, great! You collect the actual printed manuals or PDF files?

Yes I collect the actual printed manuals, but I also made PDF's of them, if somebody asks a copy.


@ banat:
Thank you very much for this copy, it completes my collection.
And I did not know that there was also a 10 and 20 kW version.
Do you have more information ??

 

[banat]

Here is one more original old document for Misissippi colection, related to Philips EL 6471 tube Power Amp.

Please read the bottom of this document , there is signed that customers can demand Power Amp with 2 KW , 10 KW or 20 KW of output power from Philips AG Deutschland .

Best Regards

 

[sansuii]

Philips EL6471 Service Manual + Schematic(pdf) : http://83.117.57.34/nvhr/Philips_EL6471.pdf

Thank you for the schematic. If i had this Information fife years ago, this could have saved myself a lot of work with my own amplifier.

::GU81-Amp::

Did you know or somebody else how much the voltage at -3 is?

[img=http://www.abload.de/thumb/el6471uuyj.jpg]

Best,

 

[Pano]

That's an impressive amp! Thanks for posting.
The OPT must be a beast. 😱

 

[banat]

Hi Sansuii !

My hat down for your Gu81 Amp !

I never made really serious schematic analysis of this Philips Power Amp but I guess that -3 value is about - 240v , but not 100 % sure since the -3 Voltage network include strartup/protection 60sek. thermorelay B16 .Any way schematic Nr. 2 (with SS HV rectifier ) in that pdf file is more accurate than schematic Nr.1 since the secondary S4 is shorted over SS rectifier via S4 CT in schematic Nr.1 ( error in drawing ) .

All the Best !

 

[jez]

I would love to see the 10 and 20 KW versions! 😱

 

[banat]

I would love to see the 10 and 20 KW versions! 😱

Sorry but until yet I have nothing else except the few more picture of Philips EL 6471 1Kw Power Amp .

Best Regards

 

[ingenieus]

Does anybody know what the cost of one of these behemoths was back in the day?