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Output transformer for 845, GM70, 813 and FU-13 - cheap and good
- Thread starter audiodesign
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It looks good at medium-low frequencies, although there is no info about distorstion at low frequency, for example. From the measurements and the other specs it appears to have significantly higher losses in treble region.
The great difference in primary and secondary DC resistances (the secondary resistance translated to the primary is about 325 ohms) makes me think that most of the useful winding space has been used to minimize the primary DC resistance.
As a starting point for me, the configuation for overall minimal losses is half space for the primary and half for the secondary because there is the possibilty to minimize the forgotten AC resistance of the windings which adds up to the DCR.
Basically here the high end response has been traded-off for more bass performance. It's a necessary compromise in affordable high power SE amps however this not necessarily is a bad thing for the final sonic performance.
45
The great difference in primary and secondary DC resistances (the secondary resistance translated to the primary is about 325 ohms) makes me think that most of the useful winding space has been used to minimize the primary DC resistance.
As a starting point for me, the configuation for overall minimal losses is half space for the primary and half for the secondary because there is the possibilty to minimize the forgotten AC resistance of the windings which adds up to the DCR.
Basically here the high end response has been traded-off for more bass performance. It's a necessary compromise in affordable high power SE amps however this not necessarily is a bad thing for the final sonic performance.
45
News, first measurements on driver stage with Fiat choke
GM70 amplifier with Fiat transformers
EMU input
GM70 amplifier with Fiat transformers
EMU input
After about one month from my payment I have received a pair of SE transformers for my GM-70 tube amplifier.
Double C core, 0.1mm laminated. I saw pictures from AudioDesign (0.35mm laminated), but my transformers are not 'bare'. I did not ask for special aesthetics, but they really surprised me. I do recommend Fiat SRL to everyone.
Just for the record, I do not have any type of benefit for recommending this company. Just another happy customer.
P.S. I think that picture can't describe how big and heavy they are
Greetings
Double C core, 0.1mm laminated. I saw pictures from AudioDesign (0.35mm laminated), but my transformers are not 'bare'. I did not ask for special aesthetics, but they really surprised me. I do recommend Fiat SRL to everyone.
Just for the record, I do not have any type of benefit for recommending this company. Just another happy customer.
P.S. I think that picture can't describe how big and heavy they are
Greetings
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I am sure you will be happy with these transformers, many time has been lost to search the best winding combination to optimize the performances.
I have used this type also in a my 845 amp.
845 amplifier with Fiat transfomers
In a direct comparison the sound and the measurements are equal or better than known brands such as Tango, Bartolucci and Lundahl.
I have used this type also in a my 845 amp.
845 amplifier with Fiat transfomers
In a direct comparison the sound and the measurements are equal or better than known brands such as Tango, Bartolucci and Lundahl.
They can ship worldwide but I don't know if they can accept Paypal, in any case a bank transfert can be used without problems.
email: [email protected]
email: [email protected]
Amps are finished and working very very good! I'm very happy with the end result.
Full size pictures:
Picture1
Picture2
Picture3
Input tube is 3A5 (DCC90, sections in parallel)-->4P1L(triode)-->interstage-->GM-70 (1100V 90mA)-->Fiat transformer (double C core, 0.1mm laminations)
Once again I highly recommend Fiat transformers.
Full size pictures:
Picture1
Picture2
Picture3
Input tube is 3A5 (DCC90, sections in parallel)-->4P1L(triode)-->interstage-->GM-70 (1100V 90mA)-->Fiat transformer (double C core, 0.1mm laminations)
Once again I highly recommend Fiat transformers.
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