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Transformers for 300b build

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Wheel you are located in the UK apparently, something that would be useful to disclose since shipping from the U.S. would be prohibitive.

Hammond transformers are imported into the UK and Sowter is local. Perhaps Monolith Magnetics in Belgium would be another option to consider depending on budget. (I use their products and recommend them highly)
 
Best 300B SE OPT?

36 pages of information on this thread. General idea is that Monolith is as good as just about anything out there except esoteric windings. Best combination of quality and value may be NP Acoustics from Vietnam if you want amorphous core. Otherwise read the thread if you have time to kill! I'm in the UK so my choices have to take shipping and customs into consideration, and that puts US products at a disadvantage.
 
Yes there is a great deal of choice out there now!
After listening to Amorphous and Nanocrystalline , Grain Orientated M6 M4 and even M3 do not have the revealing qualities these metals provide, no matter how clever the winders have become with GOSS.
This may open up quite a debate, but until people have tried the more efficient core materials with Multifilar winding the discussions will carry on .
A number of us have listened to NP Amorphous Cores and not found them overly bright compared to GOSS cores, just more revealing .
To be fair I have not heard Monolith GOSS products, the price put me off,especially for Nanocrystalline which if I had the money would go for .
I have found Nano the most revealing Transformer I have ever listened to, like a class D amp on steroids but not bright at all.
You can hammer them very hard and in the single ended domain don't run out of puff and go all fluffy when very demanding tracks are played .
I have compared all these metals now from M19 from Electra Print through all the GOSS cores including Double C core M3 Grain Orientated Steel to the exotics and time has simply marched on with people like Monolith and Teramoto venturing into Nano.
Permalloy with high percentages of Nickel are probably my favorite at present, very seductive sound and crystal clear,Dave Slagle and others leading the way with that metal .
I hope there comments are taken with the hope of opening up DIYers to taking more risks and finding out for them selves .
 
theaudiofeast.com sell Teramoto Finement Nanocrystalline Output Transformers made by Mr Suzuki formally the winder for Noguchi Transformers now out of business.
They are essentially Noguchi rebranded but have tried them and are exceptional in performance quite a bit cheaper than Monolith Magnetics Nano but still not cheap
 
Yes there is a great deal of choice out there now!
After listening to Amorphous and Nanocrystalline , Grain Orientated M6 M4 and even M3 do not have the revealing qualities these metals provide, no matter how clever the winders have become with GOSS.
This may open up quite a debate, but until people have tried the more efficient core materials with Multifilar winding the discussions will carry on .
A number of us have listened to NP Amorphous Cores and not found them overly bright compared to GOSS cores, just more revealing .
To be fair I have not heard Monolith GOSS products, the price put me off,especially for Nanocrystalline which if I had the money would go for .
I have found Nano the most revealing Transformer I have ever listened to, like a class D amp on steroids but not bright at all.
You can hammer them very hard and in the single ended domain don't run out of puff and go all fluffy when very demanding tracks are played .
I have compared all these metals now from M19 from Electra Print through all the GOSS cores including Double C core M3 Grain Orientated Steel to the exotics and time has simply marched on with people like Monolith and Teramoto venturing into Nano.
Permalloy with high percentages of Nickel are probably my favorite at present, very seductive sound and crystal clear,Dave Slagle and others leading the way with that metal .
I hope there comments are taken with the hope of opening up DIYers to taking more risks and finding out for them selves .

I have been using Nano for close to 20 Years with audio transformers...There are others I know of who have use it as well.. I agree it makes for great detail.... The price is up there since you need to buy in quantity... So far there is not enough demand for it since most will not pay the money.. Majority wants the cheapest OT's and think it sounds great... so the market is not big enough to justify me stocking up on these cores..
At my day job I use Nano cores to make 10 Mega Watt 3-Phase transformers and inductors...since I am not paying from my pocket...LOL
 
When ever I hear words like "more revealing" in descriptions of passive audio components, I start to wonder about frequency response and harmonic distortion measurements.

You should also consider Noise Floor...
The reason Nano cores are very popular in MIL applications is due to the low noise... The Magnetostriction is very low in these cores...which translates to a quieter background...
The other thing to consider is very low core loss with Nano-cores....this translates to smaller details getting through...
 
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A number of us have listened to NP Amorphous Cores and not found them overly bright compared to GOSS cores, just more revealing .I hope their comments are taken with the hope of opening up DIY'ers to taking more risks and finding out for themselves .
I use NP Amorphous Cores and they were good value for money. Clearer than my O-Netics OPTs, though I also like the "commercial" OPT designed for the Wright Sound 2a3 amp. I have 2a3 outputs. I'd be happy to recommend the NP OPTs. Very nice guy too.
 
If I were in the UK, I would order Toroidy for the power transformers (assuming shipping from Poland is not expensive). If you want a matching set of top shelf iron, go for it. But for power transformers I don't see a reason to spend a lot of money. Less need to worry about radiated fields with toroids. The same goes for chokes. I am in the US and have bought quite a few from Antek.