Regarding transformer shielding: how thick should the mu metal sheet be ?
- as thick as possible ? As thin as possible? Or it just doesn’t matter ?
Also, is 99.9% nickel foil suitable or should I really source “mu metal” ?
Many Thanks! (I really need to finish building that amp after all these years !)
- as thick as possible ? As thin as possible? Or it just doesn’t matter ?
Also, is 99.9% nickel foil suitable or should I really source “mu metal” ?
Many Thanks! (I really need to finish building that amp after all these years !)
Ho well.. I found this paper
https://iopscience.iop.org/article/10.1088/1757-899X/200/1/012045/pdf
Seems in theory mumetal is much better, but in practice doesn’t make much difference.
Also it should have been obvious, but the shielding should be as thick as possible
Is that correct?
https://iopscience.iop.org/article/10.1088/1757-899X/200/1/012045/pdf
Seems in theory mumetal is much better, but in practice doesn’t make much difference.
Also it should have been obvious, but the shielding should be as thick as possible
Is that correct?
Lol so true!
Also, it seems the shielding box should not be too close to the transformer, or it will “attract” the magnetic field.
Also, it seems the shielding box should not be too close to the transformer, or it will “attract” the magnetic field.
If I may ask another question...
2SK1530 / 2SJ201 being practically unobtainium (especially since I'd need to buy many for matching), would the 2SK1529 / 2SJ200 complementary pair be suitable for M2 ?
They seem like exactly the same thing in a different package... 🙄
2SK1530 / 2SJ201 being practically unobtainium (especially since I'd need to buy many for matching), would the 2SK1529 / 2SJ200 complementary pair be suitable for M2 ?
They seem like exactly the same thing in a different package... 🙄
keep them cooled properly and you're good
though , for tougher load , better using IRFP240/IRFP9140 pair ......... xconductance etc. being reason
though , for tougher load , better using IRFP240/IRFP9140 pair ......... xconductance etc. being reason
I have a M2 running the 2SK1530 / 2SJ201 combo and it sounds very good even on magnepans but more power is needed for bass! Is there any way to get more power out of the amp! I have the 5u 500mm case so heat dissipation isnt a problem at this point! Any idea?
Last edited:
The question is if you need more voltage swing or more current? …..or both….it depends on the speaker impedance at the low end?
My guess is that more current is needed if the magnepans goes low in impedance?
Then you need higher bias. Zen Mod made the M25 which is a M2 running at higher bias (as I have understood it) so maybe you can look at the M25 schematic and get some ideas on how to raise bias?
My guess is that more current is needed if the magnepans goes low in impedance?
Then you need higher bias. Zen Mod made the M25 which is a M2 running at higher bias (as I have understood it) so maybe you can look at the M25 schematic and get some ideas on how to raise bias?
Magnepans are current hungry speakers. I used to have a pair of 1.6QRs and a 50WPC tube amp wasn't enough power. A Threshold S/500 (250WPC into 8 ohms) seemed like the "bare minimum" - at least with loud rock music!
I mean - writing in bold and big font , pretty much the same as shouting 
of FW format amps , I can think of bridged F4 ( which means two regular stereo ones driven with balanced signal) , F5 Turbo (iteration you're ready for) , damn big BA3 ...... maybe you could even like amp from recent alive thread - AB 100W amp
there is slight possibility that Babelfish M25's 50W/4R could make some difference , counting on fact that 40W of these is in A class , but I can't guarantee that
so ..... build and try
of FW format amps , I can think of bridged F4 ( which means two regular stereo ones driven with balanced signal) , F5 Turbo (iteration you're ready for) , damn big BA3 ...... maybe you could even like amp from recent alive thread - AB 100W amp
there is slight possibility that Babelfish M25's 50W/4R could make some difference , counting on fact that 40W of these is in A class , but I can't guarantee that
so ..... build and try
