Hello Tho,
Wait untill you will have your Lundahl chokes in December.
Can you use the Tango from France in this amp too.
Greetings, Eduard
Wait untill you will have your Lundahl chokes in December.
Can you use the Tango from France in this amp too.
Greetings, Eduard
I tried to connect Peerless 16688 (impedance ratio 150:4) in my Ironamp and the result is very good and very difficult to return to hear Edcor CXSE25-8-150🙄
Now, I can built a Ironamp with all Peerless transformer😛
Magic Moment: Altec 9476A Monitor Amplifier
Now, I can built a Ironamp with all Peerless transformer😛
Magic Moment: Altec 9476A Monitor Amplifier
Hello Tho,
You dont wanna try r core power transformer for this amp?
Did you already use your Tango output transformers?
You can answer me by yahoo mail
Greetings, Eduard
You dont wanna try r core power transformer for this amp?
Did you already use your Tango output transformers?
You can answer me by yahoo mail
Greetings, Eduard
I will use Tango FG-50S for my SIT Nemesis, I just want to build Ironamp with all Peerless transformer because I very lucky to have IPT and OPT Peerless😉
About R core for this amp, I will see....😕
I built the second Ironamp with all Peerless transformer (IPT: 15280, OPT: 16688) so I called the name is... "PEERLESS"😛
Very nice, I would like to hear this. I remember you also have recently made PP VFT 2 as well. Are you using both?
I built the second Ironamp with all Peerless transformer (IPT: 15280, OPT: 16688) so I called the name is... "PEERLESS"😛
Always pleasure to see your diy amplifiers Nagini & congratulations !
Do in/ out transformers change the final sound a lot and do you like it ?
Best regards
@plasnu: yes, I'm using both, singled end and push pull show difference sound but they are so good!
@soundhappy: the sound so good and very special!😛
@Jamahamvui: your amp is...the Beast, not beauty😀
@soundhappy: the sound so good and very special!😛
@Jamahamvui: your amp is...the Beast, not beauty😀
@ Dantwomey
Congratulations! Bravo!
Not many was build....what Is Your report about Iron amp sound ?
Congratulations! Bravo!
Not many was build....what Is Your report about Iron amp sound ?
The sound is incredible but I don't have anything to compare it to. I'm hoping Father Pass remedies that in March! 😉
Regards,
Dan
May I ask you guys some question on why you used the 2sk180 the way you used it ?
My target: See what I can get out of it with max. reusage of my existing setup, which is a fixed bias, 801A/300B amp, IT coupled with nice 1:1 nano IT. It would ne nice to maybe change the OPT, but besides this...a 2sk180 could do the job of a mighty 211 or even bigger triode...
Sooo, I had a look into the data sheet:
http://www.amplimos.it/images/2sk180 datasheet.pdf
What struck me are a couple of things:
- mu is dependant of Vds with approaching 300V and 100mA maxing out at a mu of approx. 18...above 300V/100mA its constant...which is desirable I guess to have a constant mu...think of distortion
- Input capacitance is falling quiet significantly when raising Vds: 1V: 3000pf, 100V: 2000pf, 400V ??? I would guestimate clearly below 1000pf, maybe 500 pf ?
- Maybe its just my old eyes, but the HV curves look pretty much more linear to me than the LV curves, no ? I still would say the usable area should be from -10V to -30V only with min. current set at 100mA for the loadline...so I took out my ruler and draw some loadlines....
Being a tube guy, I would shoot for a setting of:
- 420 B+/Vgs
- 350mA current initially, maybe 500mA later, so with 147W initially 50% safe below the 300W of the device (2sk180)
- Bias of around -20V I guess
- Load line at 1300ohm, giving us a nice flat line to minimize distortion and maximize damping factor.
- This gives into a a 6ohm speaker 21W...which is a lot, at the level of a 845 already
Alternative settings:
- Same as above, but 500mA bias at 420V, 630 ohm primary load: 43W
Or a bit lower HV (but this means the variable Mu below 280V will create even more distortion when the signal travels through the loadline/curves):
290V, 500mA, 290ohm primary, 20W power
Does this makes sense ?
I have no pratical experience with this device, so it is a bit unclear to me if the high current, low voltage /low load approach or the approach I just described makes more sense...or something in the middle...maybe someone has already looked into that before ?
What happens when the voltage swings (as the input signals swings) above 600V ? For a tube it does not matter as long as the bias is withing the specs, is this the same with a SIT or is it simply dead ?
My target: See what I can get out of it with max. reusage of my existing setup, which is a fixed bias, 801A/300B amp, IT coupled with nice 1:1 nano IT. It would ne nice to maybe change the OPT, but besides this...a 2sk180 could do the job of a mighty 211 or even bigger triode...
Sooo, I had a look into the data sheet:
http://www.amplimos.it/images/2sk180 datasheet.pdf
What struck me are a couple of things:
- mu is dependant of Vds with approaching 300V and 100mA maxing out at a mu of approx. 18...above 300V/100mA its constant...which is desirable I guess to have a constant mu...think of distortion
- Input capacitance is falling quiet significantly when raising Vds: 1V: 3000pf, 100V: 2000pf, 400V ??? I would guestimate clearly below 1000pf, maybe 500 pf ?
- Maybe its just my old eyes, but the HV curves look pretty much more linear to me than the LV curves, no ? I still would say the usable area should be from -10V to -30V only with min. current set at 100mA for the loadline...so I took out my ruler and draw some loadlines....
Being a tube guy, I would shoot for a setting of:
- 420 B+/Vgs
- 350mA current initially, maybe 500mA later, so with 147W initially 50% safe below the 300W of the device (2sk180)
- Bias of around -20V I guess
- Load line at 1300ohm, giving us a nice flat line to minimize distortion and maximize damping factor.
- This gives into a a 6ohm speaker 21W...which is a lot, at the level of a 845 already
Alternative settings:
- Same as above, but 500mA bias at 420V, 630 ohm primary load: 43W
Or a bit lower HV (but this means the variable Mu below 280V will create even more distortion when the signal travels through the loadline/curves):
290V, 500mA, 290ohm primary, 20W power
Does this makes sense ?
I have no pratical experience with this device, so it is a bit unclear to me if the high current, low voltage /low load approach or the approach I just described makes more sense...or something in the middle...maybe someone has already looked into that before ?
What happens when the voltage swings (as the input signals swings) above 600V ? For a tube it does not matter as long as the bias is withing the specs, is this the same with a SIT or is it simply dead ?
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Ok, i digged deeper and found this nice white paper from Helmut Weigl on SIT at HV...
http://www.roehrentest.de/SIT_EN.pdf
So, he reports of oscillations when going above 300V B+ and advises not to use a 600V device above a bias of 300V when using transformer loaded...he got as well some nice curves in there for the area of 0 to 340V up to 300mA which his tube tester could record....Ok this reminds me of the circuit in the data sheet where they used 275V ...with choke input...
http://www.roehrentest.de/SIT_EN.pdf
So, he reports of oscillations when going above 300V B+ and advises not to use a 600V device above a bias of 300V when using transformer loaded...he got as well some nice curves in there for the area of 0 to 340V up to 300mA which his tube tester could record....Ok this reminds me of the circuit in the data sheet where they used 275V ...with choke input...