Slamming respectable manufacturers with long history of high-quality products doesn't make yours looking better, especially without any technical details and side by side tests.
Hi LG,
Maybe you forgot. Ciro is a very experienced OPT manifacturer. Around 15 years ago, in Sakuma-style and WOT-preamplifier era, known and experienced DIYers used and measured Ciros transformers. They were outstanding results.
For my taste, its transformers were huge in size and too expensive for me
Hi LG,
Maybe you forgot. Ciro is a very experienced OPT manifacturer. Around 15 years ago, in Sakuma-style and WOT-preamplifier era, known and experienced DIYers used and measured Ciros transformers. They were outstanding results.
For my taste, its transformers were huge in size and too expensive for me
Thanks RajkoM, you would be surprised knowing that with today magnetic materials you can have way better transformers but prices of similar models are actually lower.
Copper losses (Rdc) for 2A3/300B model 3K5/8 ohm
entry level (2.2 Kg)
2 slots 10 sections winding
.29 ohm secondary + .28 ohm primary (reflected)
top level (4.5 Kg)
4/8 slots 56 sections winding
.18 ohm secondary + .19 ohm primary (reflected)
Cores FeSi
entry level: custom size - standard 40 mm ribbon .22 mm lamination
top level: custom size, custom annealing, .10 mm lamination
but be aware that lamination thickness actually says very little on actual quality of the magnetic material
Intermediate models have different cores and sizes.
Please note that 15 years ago models had lower copper losses and wider bandwidth (up to 4.5 Hz-175 KHz -3Db) but more traditional windings.
Those OPTs where better on paper, but soundwise could not compare to my more recent design.
Improvements are in the rise and decay times with complex musical signals. Not so easy to show on paper.
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I don't know what the price is what he is asking but i can tell you this. Core materials and copper not more then €45,- and at most 4 hours to build a propper transformer ( incl coffee break
4 hours (including two coffe breaks
) is enough for a very well made Crowhurst style 2 slots 18 sections OPT.More complex windings require longer time.
€45 buy average FeSi cores and copper.
Better materials costs more (no, Santa Klaus does not brings premium cores
)You are fully right that the thickness dosn't say anything about the actualmagnetic quality. That's why i ask what the coreloss is of the cores you use. Costom annealing dosn't ring a bell ......
And would you be so kind to tell more details about the transformer (3,5 kg) in post 57 where it all started?
And would you be so kind to tell more details about the transformer (3,5 kg) in post 57 where it all started?
you would be surpriced what Santa did bring me
4 hours (including two coffe breaks
More complex windings require longer time.
€45 buy average FeSi cores and copper.
Better materials costs more (no, Santa Klaus does not brings premium cores
I don't know about good stuff - when we measured his outputs for a 211 SE amp the results were not very impressive. Maybe it's just my bad luck.
I measured a LL1664 lately.This is a small 3K/8Ω transformer "low cost" and is excellent made. Only copper loss is high.
Look at the 10k square wave i made. http://uploadenfoto.nl/pictures/a1df20baeb1057849958b08c0d8eb3d6.png
Foto Uploaden - Gratis je foto uploaden doe je hier
btw frequency respons of this transformer is 7Hz - 100kHz (measured at 75mA with a KT88 tube)
Not as good a the picture Ciro made but almost as....
Lundahl didn't need 4-8 slot 56 section to make such good transformer and in my opinion they are right, much less will do the job too.
With a little more attention this is possible too:
http://uploadenfoto.nl/pictures/11bd8f27d7eaa2d67fbd9ba4c28076d8.png
http://uploadenfoto.nl/show-image.php?id=38d688311c77d3ff32cb97a424161a3e
This is a small 3750Ω /16Ω transformer with even better sq response and 8HZ-110kHz
Also with much less slots/sections then Ciro needs.
So good/excellent performance for reasonable work(= money) is possible
Look at the 10k square wave i made. http://uploadenfoto.nl/pictures/a1df20baeb1057849958b08c0d8eb3d6.png
Foto Uploaden - Gratis je foto uploaden doe je hier
btw frequency respons of this transformer is 7Hz - 100kHz (measured at 75mA with a KT88 tube)
Not as good a the picture Ciro made but almost as....
Lundahl didn't need 4-8 slot 56 section to make such good transformer and in my opinion they are right, much less will do the job too.
With a little more attention this is possible too:
http://uploadenfoto.nl/pictures/11bd8f27d7eaa2d67fbd9ba4c28076d8.png
http://uploadenfoto.nl/show-image.php?id=38d688311c77d3ff32cb97a424161a3e
This is a small 3750Ω /16Ω transformer with even better sq response and 8HZ-110kHz
Also with much less slots/sections then Ciro needs.
So good/excellent performance for reasonable work(= money) is possible
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Ciro does not "need", Ciro willingly chooses, it is totally different...
Of course anybody is free to walk is own path
I agree that small, low cost OPTs can measure amazing, especially when it comes to square waves. Look at this small, "low cost", 2 slots / 10 section unit:
actually this is a little off topic, because this is a 4.5 Kohm / 8ohm OPT meant for 45, RE604, etc. (not a 300B OPT) but it gives the idea of a close to perfection square wave.
BTW, achieving an almost perfect square wave it's easier when you accept higher copper losses.
Problem is:
Audio is not about the best looking square wave,
Audio is about reproducing the full bodied emotion, the nuances and the shrivers of real music.
At least that's my thought, and the path I am walking.
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It makes no sense to give a nice picture of a square wave if you are not telling what the frequency response is, not telling what the copper losses are, not telling what kind of core (losses) you use. So far you telling just half a story and conclusion till now : nothing special just as any other good transformer.
Btw, In the little 3750/16Ohm is a c-core with "standard" 0,85W/kg coreloss material. The copper loss is 0,19dB. Designed for a 2A3 or simular tubes.
Btw, In the little 3750/16Ohm is a c-core with "standard" 0,85W/kg coreloss material. The copper loss is 0,19dB. Designed for a 2A3 or simular tubes.
Ciro does not "need", Ciro willingly chooses, it is totally different...
Of course anybody is free to walk is own path
Mate, I see you do not get the point (or may be you do not want to get it).
I am not interested in playing "my triode is longer, my triode is stiffer" game.
(The same applies to "my OPT is longer, my OPT is stiffer"
)In fact the last square wave I have posted is of an obsolete unit.
YES, that OPT had a frequency response of 11Hz-320KHz -3Db (being the clever guy you are, I am sure you noticed that was a 30KHz square wave).
BUT, despite looking so nice at measures, and despite costing only 95 euro when discontinued, this is an obsolete unit.
And it is an obsolete unit for the very simple reason that its sound was just slightly better than the sound of "mainstream commercial crap with a famous name" OPTs.
Better but still similar.
Not what I was looking for.
This explain why today I am making OPTs with different design.
Because I want music, not just sounds, nor just nice looking square waves.
I look for quality in real life.
BTW: core magnetic losses make sense when related to induction in the actual transformer. Declaring losses at 15000 or 17000 Gauss can make sense in a power transformer for non-audio use.
But is practically nonsense for either low induction audio use power transformers
or audio OPTs.
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