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    Building, troubleshooting and testing of these amplifiers should only be
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Best SE output transformer for 300B - shootout

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and in particular the performance of the 5K OPT.

If your RCL measurement and my calculation are correct, "real" measurement is coresponding -at HF- to the simulation. :)
 

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After further design work with my locally wound Australian Amorphous Core Transformers ,i have managed to get the 20Hz point down to -1dB at 1 watt, this has made a significant change in Bass response from the ISO ( tango) I use and stock.
These I have found are good performers with all types of drivers now ,not just full range Single Drivers like Lowther.
I formally posted the ISO (formally Tango) were better in the bottom end response but am much happier now with the amorphous core performance below 30Hz
ISO FE12S 20Hz-80Khz -2db and ISO FC20S 20Hz -90Khz ( New Version Old Tango XE20S)
Good Luck with Your NP Acoustics transformers !
 
No idea why they call it NanoX, but I guess it is nanocrystalline, also known as Finemet (Hitachi brand name).
Nanocrystalline is made as an amorphous strip, and becomes "nanocrystalline" by after treatment (you can find the properties by doing some searching).
In my opinion nanocrystalline c-cores combine the best properties of high grade silicon steel (permeability) and amorphous (low core losses; low eddy currents; good hysteresis properties).
Maximum core excitation however is something to take care of as it has a lower saturation treshold than silicon steel and also amorphous.
 
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I would, if I knew what to search for.
This for sure needs clarification. If you or Hanze know this better than we, just explain, or give a link.

Another handy visual aid is a frequency - reactance nomograph. Follow parameter colour on line of same colour to where it intersects with lines of the other parameters you are interested in.
 

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NanoX are a little warmer sounding than the Amorphous but the cores saturate very quickly so if you want bass down to 20Hz at -1db the cores are very large for a SE300B .

The Amorphous are better bang for the buck and will fit on a stereo chassis 400x300mm
Nano would need to occupy a much larger chassis , if you look at the size and price of Monoliths then it becomes apparent large sums of money for the full freq response is required

Freq response ,insertion loss and core saturation are all factors on the technical front , but tonality and a particular voicing ie the flavour that suits you is much more important.
No Transformer is completely Neutral , all have a particular sound.

It is important you get to listen, as you maybe far happier with an Electra-Print M19 EI core steel transformer , 25Hz - 25kHz + -1dB min guarantee .

IMHO opinion, getting rid of capacitors in the signal path and building a DC coupled amplifier has a dramatic effect on the sound of an amplifier, way before folk go looking for audio nirvana in the latest craze of core metal
 
Please share your wisdom.

This is not 'my wisdom', but principles all which can be easily understood, with some time and thought - if you take the time. This is directed to you and also the 'Artosolo'.

Your response in the collective could only be considered as rude, and I take objection to that. I try to help and through your ignorance you ask for justification of the 'evidence' in the most obtuse manner.

Like swine, better off slowly cooked over open coals.. dusted regularly with a brush laden with herb infused oil. (that is my preference for cooking - unrelated perhaps). Perhaps. Would I eat it, no. I would feed it to my dogs.

Hanze.
 
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IMHO opinion, getting rid of capacitors in the signal path and building a DC coupled amplifier has a dramatic effect on the sound of an amplifier, way before folk go looking for audio nirvana in the latest craze of core metal

+1

i have made few SETamp ( AD1 ,300B, WE412, 45, 46, E55L, RS241) with ; lundahls , amorphous or not, HASHIMOTO , Monolith magnetics , James , elcetraprint , james transformers.

i have my favorites , but can't say you can't build something good whit any of these. more easy to make a bad one with the bad ( driver/power tube) combo. :)
 
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