I would like to know more about this too.
Generally I don't worry about it because it doesn't always correlate with other metrics as far as I know.
In overclocking CPU's we are constrained with limited power budgets so it is worthwhile to look for parts with high-k dielectric but in audio circuitry I would imagine such power budget does not exist so it doesn't make sense to optimise for it.
Comparing to tubes I find it to be difficult because solid state devices don't emit visible light and hence they are different types of devices.
If power budget would not be an issue then heat may be. If I'm worried about this I can use a laser thermometer or thermal cam. How and if this translates to audio devices I don't know.
Please keep us posted if you find something interesting
Let's try triode transistors excellence....with "wide" full range " drivers speakers
Is a triode like 300B still the most linear amplification device that exists?
Or is a VFET more linear?
I am not expert looking into curves but 300B looks to me a bit "nicer" than the VFET curves?
But then we need the large output transformer and VFET only needs an output cap.
Regarding the noise issue I wonder if it is coming in via the PSU from the mains and R- channel is a bit more sensitive to this than L-channel. The theory makes good sense as the noise disappeared during the late night hours where noise level on mains is low.
It is late now and amp is silent........
Or is a VFET more linear?
I am not expert looking into curves but 300B looks to me a bit "nicer" than the VFET curves?
But then we need the large output transformer and VFET only needs an output cap.
Regarding the noise issue I wonder if it is coming in via the PSU from the mains and R- channel is a bit more sensitive to this than L-channel. The theory makes good sense as the noise disappeared during the late night hours where noise level on mains is low.
It is late now and amp is silent........
LOL! Has anybody ever pretended that a tube is a transistor?If re-soldering everything and other treatments don't help, then I suggest you
relax and pretend it's a tube....
I was about to say, the curves are close, not having to deal with an OPT vrs an output cap.
dave
Some of these SIT's was made for high voltage?
I wonder if someone has tried to run a SIT with high voltage and "low" current and then use an OPT? ....The current may be a bit higher than with a tube so a special OPT (large one) would be optimal? 50W in 8 ohm could be possible with a single device?
I wonder if someone has tried to run a SIT with high voltage and "low" current and then use an OPT? ....The current may be a bit higher than with a tube so a special OPT (large one) would be optimal? 50W in 8 ohm could be possible with a single device?
These seems to be 1200 - 1700V types (but probably sold out):
http://www.farnell.com/datasheets/1706851.pdf
800V / 200mA could be possible?
Some care should be taken regarding heatsink mount.....
Vertical JFET......
http://www.farnell.com/datasheets/1706851.pdf
800V / 200mA could be possible?
Some care should be taken regarding heatsink mount.....
Vertical JFET......
well, I'm not exactly trying ..... nor I'm excelling in being KnowItAll ...... but even I know that (unfortunately) Semisouth is gone Dodo
go to FW Articles page, and spend some time there, downloading and reading
magic word for your interest is - Nemesis ........ then everything with SIT in title
edit: Wonderland is , well, wonderful land; 800V x 0.2A is still 160W of heat; with approach as that, study all HAM stories about 6L6/807 pushed in bucket of oil
go to FW Articles page, and spend some time there, downloading and reading
magic word for your interest is - Nemesis ........ then everything with SIT in title
edit: Wonderland is , well, wonderful land; 800V x 0.2A is still 160W of heat; with approach as that, study all HAM stories about 6L6/807 pushed in bucket of oil
Last edited:
I think I read something about Nemesis.....but not everything......maybe I should do that!
I remember a lot of curves.....also for 300B....but only 45V for the SITs using OPT? will have a look again.
While trying to understand why I sometimes can hear a bit of flicker noise with ear 5cm from tweeter I found this article:
https://tel.archives-ouvertes.fr/tel-00767284/document
....but trying to understand everything in this......I may just listen to more music and then maybe use an evening re-flowing right channel and then see if this will change anything......
But strange SemiSouth could not keep going as these power JFETs was used for solar energy etc?.....where demand is increasing. Maybe cheaper MOSFETs has taken over this duty and these are not as good for audio.......just a guess....
I can try to order some of these SemiSouth's at Farnell and see what happens.....
I remember a lot of curves.....also for 300B....but only 45V for the SITs using OPT? will have a look again.
While trying to understand why I sometimes can hear a bit of flicker noise with ear 5cm from tweeter I found this article:
https://tel.archives-ouvertes.fr/tel-00767284/document
....but trying to understand everything in this......I may just listen to more music and then maybe use an evening re-flowing right channel and then see if this will change anything......
But strange SemiSouth could not keep going as these power JFETs was used for solar energy etc?.....where demand is increasing. Maybe cheaper MOSFETs has taken over this duty and these are not as good for audio.......just a guess....
I can try to order some of these SemiSouth's at Farnell and see what happens.....
well, I'm not exactly trying ..... nor I'm excelling in being KnowItAll ...... but even I know that (unfortunately) Semisouth is gone Dodo
go to FW Articles page, and spend some time there, downloading and reading
magic word for your interest is - Nemesis ........ then everything with SIT in title
edit: Wonderland is , well, wonderful land; 800V x 0.2A is still 160W of heat; with approach as that, study all HAM stories about 6L6/807 pushed in bucket of oil
Did you say 807? One of my favourite tubes - love the anode cap on the top for that nostalgic safety:
I built that well before DoDo era. The secret? 10Kohm Williamson spec OPT. The schematic ; very like RCA red handbook.
i have built 2 version of them , one with the Sony 2SK82 and Edcor 64ohm OT and the second with TOKIN 2SK182 and Tango FW50 Nemesis style.
the edcor version was not as good as all the other L'amp Vfets in fact i did'nt like it at all . the TANGO was fun sounds more like a beefy 300B SET . but the Tango OPTS are very hard to Find and very expensive.
but at the end if i had to rebuild one the IronAMP with hammond 193choke was my preferate . easy to build , half the power supply of the Lamp .
and the keeper is this last DIY SOnyVfet . it would be funny to go to a hifi store with it and say can i compare my Diy amp to your big dollars ones
