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Most exotic SET power amplifier

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I think some of those transformers are chokes, and others are to power the rectifier filaments. When you have your own transformer winding machine and can produce whatever you need on demand, you have more options.

A high power SET amp will necessarily be heavy. They are usually split into multiple units, like having the power supply in its own enclosure. Personally, I think the weight of this amp is actually reasonable for a Class A single-ended amp of this power level, be it tube or SS.


Oh oh, this post is not gonna be understood by many. Me included. I have special problems with the word 'reasonable' placed there, in the description of that amp.
 
Oh oh, this post is not gonna be understood by many. Me included. I have special problems with the word 'reasonable' placed there, in the description of that amp.

Have you ever made, or designed in your head, a single ended Class A amp that must dissipate 200-300W of heat on idle? Even with SS, that's 60 pounds worth of heatsinking.

I've worked with 6-channel professional amps used in theatres. They are not even Class A, but had a lot of power output and a lot of heatsinking. Those amps weighed over 100 pounds! You see, it's nothing unusual in the world of amps.

My friend's van, has 200 pounds worth of amps, not including the extra batteries.

The modern trend in high end speakers is to make the enclosures out of aluminum. Each speaker weighs 800 pounds! That's 1600 pounds in stereo!
 
Hi folks.
Thank you all of you for your good words and valuable comments.
This is a project that lasted somewhat more than a whole year.
What I had in my mind a year ago was to manufacture completely from scratch a super amplifier, trully exotic, something that probably has never been made so far. The majority of the 'extreme' work that this machine needs, specially in coil winding, is totally unseen or obscure. The complexity of the winding of all the transformers cannot be understood without dismantling and reverse engineering.
Anyway, with this project I wanted to show to some friends and to the DIY community that everything depends on the boundaries of your imagination. Just imagine the end result and... bingo, you've got it. Remember that I live in Greece where the economy is dying due to the recession, however if you have the skills and the courage, you can surpass every obstacle that may appear during the trip.
I just saw that many of you are asking for the transformers, or wonder why so much iron. I need to underline that the extraordinary level of performance of this amplifier lies in the quantity and quality of iron. I have told to many friends that the level of performance of a well designed SET is proportional to the weight of the iron! Use more iron and you get better sound, so simple, provided that everything is up to its task.
On this design, I have used the following iron pieces:

1x filament transformer for 1st pair of 866A MV rectifiers
1x filament transformer for 2nd pair of 866A MV rectifiers
1x EML20A filament transformer
1x 300B filament transformer
1x 211 filament transformer
1x HV transformer for EML20A & 300B tubes
1x HV transformer for 211 tube
2x HV supply chokes for 211 tube
3x HV supply chokes for EML20A & 300B tubes
1x Interstage transformer for EML20A tube
1x Interstage transformer for 300B tube
1x Output transformer for 211 tube

All the above make a total of 15 iron pieces per monoblock.
Being a coil winder, I have access to my winding machine so I'm able to materialize any crazy idea that comes into my mind.
I will come back with full description of the amplifier after the weekend.
Peter.
 
that's a piece of art. using 300B as driver probably is the smartest thing to do

what is the enclosure made of? seems solid aluminum with some endless CNC machinery hours.
is this the final look? is there any dust cap or something like a hat to cover all those terminator robot-looking irons? as the voltage is +1000V I think this gear should be used by an expert or you may hurt someone with that toy of yours:D;)
 
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Here are some new pics with the dangerous irons fully covered.
I am still waiting for the tube caps but the post office still plays a bad game here...
211 has been pushed to its maximum voltage limits, 1250V anode to cathode.
The chassis is made out of corian with endless working hours on the CNC.
 

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I think that definitely qualifies as exotic. Looks like a lot of hours, beautifully executed, obviously a labor of love. I wish it was as simple as "Just imagine the end result and... bingo, you've got it." I can imagine a lot but I know I will never have the skill to do what you've done.

If you can ever get the thing turned over, it would be interesting to see the inside.
 
Disabled Account
Joined 2004
Have you ever made, or designed in your head, a single ended Class A amp that must dissipate 200-300W of heat on idle? Even with SS, that's 60 pounds worth of heatsinking.

Sorry, you're right. I didn't read your post that well. Anyway, no, I will never build such a monster because I find it unreasonable. Not that I dislike crazy amps, but somebody else would have to build it for me. Haha, that stuff is scary. Too many volts and too many pounds.

petavgeris- That amp is a beauty.
 
I think that definitely qualifies as exotic. Looks like a lot of hours, beautifully executed, obviously a labor of love. I wish it was as simple as "Just imagine the end result and... bingo, you've got it." I can imagine a lot but I know I will never have the skill to do what you've done.

If you can ever get the thing turned over, it would be interesting to see the inside.

Thanks for your kind words.
You are right, this creation is a labor of love. I really loved it from the first moment, as soon as the whole idea was captured into my mind. I wanted to show what is possible sound-wise and at the same time have nice and luxurious aesthetics. Unfortunately it is not possible to show the surface of the highly lustrous corian, under normal lighting conditions it draws your view like no other. I wanted to follow classic vintage design line with rectangular cases allover but at the same time give a modern look with contemporary 'feel' that inspires you to listen and watch, all at the same time. Above all, I wanted to avoid any bolt head that harms the unique contemporary look, only two are visible, on the IEC mains socket.
Turn this thing upside down? Hm, I doubt if it is possible, 4 strong men are needed. Anyway, there is almost nothing inside, only 3 heat sinks for tube rectification diodes and 3 caps for filament supplies, one per tube. There are also 3 regulators inside, giving power to the filaments. This is it.
Thank you for your kind words once more.
Peter.
 
I also think you've done a great job with this amplifier. According to the Dupont website, this material thermo forms at 150º C (300ºF). I hope you don't run into deformation problems from the tube heat with long term operation.

Hi!
After assembling the parts and igniting the tubes, I realized that after 3 hours of continuous operation, they run much cooler inside the chassis than laying on the bench. The heat sinks and the passive ventilation channels really do a lot of work there... This was a bit expected but not to this degree, as the heatsinks are at least 15 deg cooler. You touch them and you just feel they're warm, not even hot! Thermal stress is subminimal and the amp runs unexpectedly cool, of course this is welcomed. Transformers run cool as well, being either HV or filament.
 
or pets...

Consider some tempered glass to protect the hands from the mercury rectifiers??

Ceramic plate caps are insufficient, better than bare metal, but insufficient, imo.

also watch the temp inside the xfmr cans... best to provide some cooling paths from below at minimum...

_-_-bear

Yes, corian and other solid surface materials finish up very nicely.
 
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