I ordered it from a place in Maryland named toroid corporation. It was $450 but it was a special requirement where it had to be made narrower & taller than typical because of some space issues I had.
Foil wrapping a fuse totally eliminates its function. Your insurance company will be very happy for not paying you the damages because of the fire it will eventually cause if something goes wrong.
This 18-kilogram transformer cost the customer $ 559.33, its power density per kilogram is 220 VА, and you have 166 VА.
Difference in specific power 1.325 times (220VA/166VA)
Apparently because it is 1.56 times more powerful (3900VA / 2500VA).
The price difference is only 1.22 times.
Tape from electrical steel ЭT 3425 (Hi-B) 0.1mm thick.
Naturally, one should take into account the error in the exchange rate, and the difference in the calculation of power and weight. There are always roundings somewhere.
Difference in specific power 1.325 times (220VA/166VA)
Apparently because it is 1.56 times more powerful (3900VA / 2500VA).
The price difference is only 1.22 times.
Tape from electrical steel ЭT 3425 (Hi-B) 0.1mm thick.
Naturally, one should take into account the error in the exchange rate, and the difference in the calculation of power and weight. There are always roundings somewhere.
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Actually I don't think that I did that, but I think the fuse is so overrated that it's about the equivalent of foil wrapping. Slow blow 'something big' size fuse. It may even be paralleled with another (2) I never got around to testing how low a rating I could use while reliably performing. Just used it. Still an amazing amp, never ever pushed and got it to distortion levels before the pain just sets in and fear of the speaker cones shredding. It was the more is better bug that I had a long time ago. I'm happy with ~250w/ch anymore. Maybe half that thing
i built 300 watt super leach amps, it is like having a car that can do 300km per hour and you are not running them at that speed, 40 to 60 cruising is more like it, but when bursts of speed is needed, you have it....
in our FTC testing we confirmed a 1000 watt amp to be true, but actual listening, a power input of about 300 watts delivered uncomfortable ear splitting volumes, lesson here is that power using sine waves are never the same as when playing music....
any power amp clipping at 1000+ watts sine wave may clip at 300 watts using music on real speakers instead of dummy resistor loads...
that is why amplifier power is only good for dimensioning components for testing using sine waves, when built up, that power number is meaningless, the only thing is that you built the amp to be able to deliver an FTC power of 1000 watts for 5 minutes....
in our FTC testing we confirmed a 1000 watt amp to be true, but actual listening, a power input of about 300 watts delivered uncomfortable ear splitting volumes, lesson here is that power using sine waves are never the same as when playing music....
any power amp clipping at 1000+ watts sine wave may clip at 300 watts using music on real speakers instead of dummy resistor loads...
that is why amplifier power is only good for dimensioning components for testing using sine waves, when built up, that power number is meaningless, the only thing is that you built the amp to be able to deliver an FTC power of 1000 watts for 5 minutes....
yes, but the Article do exist and perhaps the copy that was scanned had missing pages, i have the complete article but lost it when my hard disk drive crashed...
this article came out the same year that picking capacitors article came out and that started a worlwide trend...
In general, if there is a three-phase network, it is better to use it. In the USSR, there was such an amplifier "Кинап - 51У-19" on GU50 tubes for cinemas. It was not very powerful and compact. Ламповый оконечный усилитель "51У-19" | RadioNic.ru
https://forum.cxem.net/uploads/monthly_01_2011/post-127163-0-61943400-1296154181.png
https://forum.cxem.net/uploads/monthly_01_2011/post-127163-0-61943400-1296154181.png
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It's an issue of dynamic range- you don't want the amplifier clipping on transients. There is no real need for a 500 watt amplifier in a small room, but it also doesn't really hurt. That said, there is certainly a good reason for having more than 30 watts, especially if it's a larger room and the amplifier needs to do low frequencies as well. Nothing wrong with having some extra headroom.
To H713:
I, as an experienced service tech, already know about headroom among other audio-related subjects.
However I'm sure your post will educate others.
What I was saying in my previous post was not about headroom, but of typical amplifer wattage levels in the average home.
Sure, "more watts" is beneficial to have, people don't want to listen to distorted crescendos in their music.
But the wattage needed is surely not 500 watts - at least in a home environment.
Normal people like me, even pushing my floorstanding Advent maestros to "concert levels" only tops out at maybe 50 watts/channel with my solid state Technics receiver.
And my tube amp, having only 17 watts/channel, is also quite capable of annoying my neighbors with clean loud sound.
Mind you, the Advents are 4 ohms, but relatively hungry speakers.
People with a desire for hundreds of watts in the home are either power-hungry obsessed types or just meaning to impress others.
It's got nothing to do with listening to good music in the home.
I, as an experienced service tech, already know about headroom among other audio-related subjects.
However I'm sure your post will educate others.
What I was saying in my previous post was not about headroom, but of typical amplifer wattage levels in the average home.
Sure, "more watts" is beneficial to have, people don't want to listen to distorted crescendos in their music.
But the wattage needed is surely not 500 watts - at least in a home environment.
Normal people like me, even pushing my floorstanding Advent maestros to "concert levels" only tops out at maybe 50 watts/channel with my solid state Technics receiver.
And my tube amp, having only 17 watts/channel, is also quite capable of annoying my neighbors with clean loud sound.
Mind you, the Advents are 4 ohms, but relatively hungry speakers.
People with a desire for hundreds of watts in the home are either power-hungry obsessed types or just meaning to impress others.
It's got nothing to do with listening to good music in the home.
Your article disappeared into the ether, the author Walt Jung recanted it, article in historical archive is missing the relevant pages, plus lots of fear, uncertainty, and death by spontaneous combustion here in this thread from very old, experienced folks sounds a bit like the mummy's curse.
This amp will be used mostly in a meeting hall kind of room about 45 ft x 30 ft and hence it is NOT that large considering the room volume. They will most likely drive a pair of JBL's Synthesis S3900 speakers (not 100% decided yet).
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I have not quite decided but it will be one of those:
- Rod Elliott's P33 & P198
- Jan Didden's pax amplifier protection, driving Rod's P198 mosfet relay.
Regardless of which one I pick, I will be using Rod's P198 Mosfet relay in both. I will be using the Infineon IRF150P220 Mosfets (2.5 mohm max Rds and 300A) for the relay function.
I am leaning towards Jan Didden's circuit more simply because it 'latches' which I prefer in a protection circuit.
I like them both since they are SIMPLE.
- Rod Elliott's P33 & P198
- Jan Didden's pax amplifier protection, driving Rod's P198 mosfet relay.
Regardless of which one I pick, I will be using Rod's P198 Mosfet relay in both. I will be using the Infineon IRF150P220 Mosfets (2.5 mohm max Rds and 300A) for the relay function.
I am leaning towards Jan Didden's circuit more simply because it 'latches' which I prefer in a protection circuit.
I like them both since they are SIMPLE.
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