[FullRangeMan]

This Bartola link is huge, any picture?
Could it sound better with a laminated C core?

[planet10]

FullRangeMan,

Happt to see your avatar wearing a mask. Kudos :^)

dave

[FullRangeMan]

Thanks Dave keep you safe too.
Lets pray that it will pass soon.

[planet10]

Unfortunately we will have to deal with it for at least a year more i expect.

dave

[E55l2]

'

[FullRangeMan]

I can’t place a photo here because of copyrights. Just look at the site from Bartola.co.uk

The core is made from nanocrystaline material, ultra thin laminations, and this material is super good and the only not so good part of this material is that it saturate very early so for that reason the core needs to be almost twice as big as a normal HiB core.
Unfortunately the transformer you see on this site is just somewhat underrated. It will be a good transformer but for myself i would make it even a lot bigger for maximum performance.

Great, it seems perfect to 45, 2A3 or maybe EL34,KT88.

[E55l2]

'

[FullRangeMan]

Yes and no. The transformer CORE is ok for smaller output power project IF it will be REWIND. With less current for the tube there will be more space to lower the copper resistance. The core material is super, best of the best.

But how much it cost in C core?

[E55l2]

'

[E55l2]

'

[E55l2]

'

[FullRangeMan]

3-4 time is a lot of money I could be happy with Hi-B.
I have read the GU50 is a great tube so many praises.
And it just $5 each.
Do you think it sound better than EL34 /KT88 ?

[E55l2]

'

[E55l2]

'

[FullRangeMan]

I had already noted that the Cathode is only 0.7Amp.

[E55l2]

'

[mresseguie]

There’s so much to learn about amp and/or power supply architecture. Can someone explain the sonic benefits between C core and L core transformers?

Thank you,

Michael

[E55l2]

'

[mresseguie]

I know a lot of transformer types (making transformers for over 30y) but never heared of L core transformers. What you mean by a L-core?

But, the first thing in a transformer is that it has to be a good frequency response (se at least 10Hz-65kHz, pp 5Hz - 70kHz), resonance free ofcourse (also outside the audio band) and high efficency (low copperloss) if that is ok then transformer core comes second. Transformer shape is already part of the design.

Thank you for replying. 

I checked the other website and discovered I mistyped. It should be "El transformers".  I found this reference:

EI transformer is a traditional transformer. The core of EI transformer is combined by lamination E and I, so it is called EI transformer or laminated transformer. ... It is usually used as power transformer at 50-60Hz. In audio applications, EI transformer is commonly used as tube power transformer and output transformer.

Core type transformer:

A 'core type' transformer core is one in which the primary windings and secondary windings are placed around each of the limbs, as opposed to a 'shell type' core, in which the two windings are placed across the centre core.

But which kind is superior?

[FullRangeMan]

But which kind is superior?
I dont know what is better in electrical performance I will let this tech details to Martin as I not a tech. What I can inform is the EI x C sound characteristics that I already posted in other topic.

EI, C core and toroid are tools to be used, I could like more of EI if that EI lamination that have no holes in the corners to screws (rare) was easy to find. For the usual oldfashioned tube sound, warm not much detailed sound with max power of the core use EI, cheap and good enough for most audiophiles.

C core laminated HiB Z11 offer a detailed and more transparent sound.
For more details on medium or low power levels maybe amorphous core could be used but its not popular due low freq loss and iron losses bigger than C core due max flux limited, maybe amorph works fine with flea power tube amps.

On toroidal power trafos I found this:
* Toroid has better efficiency and therefore is more suitable for high power applications. But, toroid has higher bandwidth and therefore is not a good filter / isolation device. Toroid has more noise that leaks through primary / secondary compared to EI.
* Most importantly, EI sounds warmer, cleaner, better bass definition, less sibilance, and better body when compared to toroid. EI is the one to use if the power required is not extremely high.
* Toroid has lesser radiated magnetic field compared to EI and may be acceptable to use un-potted but once EI is potted in metal case or have comprehensive copper bands , it will have similar behavior on radiated noise.