Trasformatore Uscita GM70 - F.I.A.T SRL
These you mean, or full custom? I could send them an email to ask about the price because they look pretty decent.
Some DIY use Ogonowski OPT,202.0 USD I don't know the quality. You can look at the reviews on the forums.
Ogonowski.eu - profesjonalne transformatry do wzmacniaczy lampowych
Ogonowski.eu - profesjonalne transformatry do wzmacniaczy lampowych
Ogonowski makes good transformers, but that one is compromised.
A 7k primary impedance asks for at least 60H of primary inductance instead of the specified 30H.
Primary DCR of 170 ohm ...quite a bit of copper losses to expect.
The F.I.A.T. transformer is higher grade (just compare the specs).
A 7k primary impedance asks for at least 60H of primary inductance instead of the specified 30H.
Primary DCR of 170 ohm ...quite a bit of copper losses to expect.
The F.I.A.T. transformer is higher grade (just compare the specs).
I agree,the F.I.A.T. transformer is higher grade,bat if its price is the same,about $200,this condition.
Addition
Ogonowski OPT has a current of 200mA, F.I.A.T SRL 75-90ma, has 2.22 times little. The inductance is proportional to the gap. Ogonowski OPT has a current of 200mA, F.I.A.T SRL 75-90ma, has 2.22 times little. The inductance is proportional to the gap. Give an order OPT to Oganovskiy in the 90mA and its inductance will be 66H.
This is if the cost of the Ogonowski OPT is lower than others
Ogonowski OPT has a current of 200mA, F.I.A.T SRL 75-90ma, has 2.22 times little. The inductance is proportional to the gap. Ogonowski OPT has a current of 200mA, F.I.A.T SRL 75-90ma, has 2.22 times little. The inductance is proportional to the gap. Give an order OPT to Oganovskiy in the 90mA and its inductance will be 66H.
This is if the cost of the Ogonowski OPT is lower than others
When I ordered they didn't have a web site like this. Back then it was fully custom order with black covers.
See attached picture.
Attachments
I've noticed Silk Audio have a transformer wound for a GM70 , $512 USD a pair .
15Hz - 85KHz @ Frequency Response (-3.0dB)Source Impedance = 0.7X
SACThailand
15Hz - 85KHz @ Frequency Response (-3.0dB)Source Impedance = 0.7X
SACThailand
Hello Kevin, would you please to show your schematic ?
Or via mp.
Thank you in advance
Gilles.
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I have a long standing policy of not sharing my high voltage designs, so no I won't be sharing here. It is a very conventional IT coupled fixed bias design with solid state bridge rectification and CLCLC HV supply filtering.
It's what I would suggest, the GM70 is quite linear, and is pretty reliable over it's service life. It is not a type I would recommend to the inexperienced however, and I wouldn't recommend the 6C33 either in such a case.
GM-70 can do much more than 15 watts. It is more complex build and more expensive, but if you do it right you will have an excellent sounding and linear amplifier.
And, you have to set you mind that GM-70 requires about 1kV B+ and higher. I run it at 1200VDC.
6C33C isn't a "bad" tube, but GM-70 is on another level.
Almarro A318B SINGLE ENDED
Tube components: 6C33C x 2, 6SL7 x 1, 6SN8 x 1
Output Power: 18W x 2ch
Frequency response: 10-30KHz
Seems to have received very good reviews over the years .
Tube components: 6C33C x 2, 6SL7 x 1, 6SN8 x 1
Output Power: 18W x 2ch
Frequency response: 10-30KHz
Seems to have received very good reviews over the years .
Regarding the output transfomers, I contacted Vlaartronic and he told me a that pair of OPTs for SE GM70 tubes (in a pretty black box enclosure) will go for about 450 euro. Seriously considering that over the Hammonds. The "De Tsaar" project on audio-creative was built with those.