Yes You are right
Recycle cork organic material to make fabulous speakers boxes and room acoustic adjustements make sense in Hi-Fi
Is Cork Good for Soundproofing? - Better Soundproofing
Imagine SIT Tokin SE 50 Watts future class A amplifiers do have special dedicated circuits
to transform the heatsinks heat into the cold air for hot climate season time..
after automatic or user programmed temperature detection
I do register my first official patent on this solution.
I understand that the Russians or/and Chinese used wood for the re-entry tiles on their spacecraft. Once burned the carbon prevented the capsule from burnup.
"So when it came to reentry, Chinese scientists looks for the simple solution, and that turned out to be wood. Specifically, white oak wood. It’s light, doesn’t catch fire too easily, and can effectively protect a payload from heat.
The FSW satellites used a 5.9-inch thick heat shield made of oak. During reentry, friction caused the wood to burn and char, leaving behind a layer of charcoal. That charcoal was blown away in the wind as the satellite fell, exposing more oak, which burned and turned into charcoal. It’s a repeating process that ultimately allowed very little heat to get through to the spacecraft; both the wood and the charcoal are great insulators. It was a light and elegant solution to the reentry problem".
"So when it came to reentry, Chinese scientists looks for the simple solution, and that turned out to be wood. Specifically, white oak wood. It’s light, doesn’t catch fire too easily, and can effectively protect a payload from heat.
The FSW satellites used a 5.9-inch thick heat shield made of oak. During reentry, friction caused the wood to burn and char, leaving behind a layer of charcoal. That charcoal was blown away in the wind as the satellite fell, exposing more oak, which burned and turned into charcoal. It’s a repeating process that ultimately allowed very little heat to get through to the spacecraft; both the wood and the charcoal are great insulators. It was a light and elegant solution to the reentry problem".
If anyone needs them....
https://www.diyaudio.com/forums/swap-meet/379718-fs-uk-matched-pairs-tokin-thf51s.html#post6856636
https://www.diyaudio.com/forums/swap-meet/379718-fs-uk-matched-pairs-tokin-thf51s.html#post6856636
Tokin are generous with the power and the gain available
....but distortion % is higher than Sony Vfets , maybe they need John Broskie
aikido style trick etc.
The Tube CAD Journal: Inverse pre-distortion cancellation
There is also a method here called the "Sakuma method". But don't know if the tube method can be used using SIT's.....using same device as driver and output then and then "playing" with the "working point" of the driver to lower even harmonic distortion......and I don't think I understand why it works either.....
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Apart from that GM70 looks like a nice tube......
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Apart from that GM70 looks like a nice tube......
There is no need to complicate the circuit. This is the Harmonic distortion measurements of a Fokin (THF-51S) with a PSU of only 24 V, 2.6 A and Vout = 2.82 Vrms. The Bias can be adjusted to lower the THD. However a clearly predominant second Harmonic is lost. If it has to look like an 845....
The curves looks ok in these measurements?
http://www.roehrentest.de/SIT_EN.pdf
There are a lot of THF-51 for sale at aliexpress.....but they probably won't sound good......
http://www.roehrentest.de/SIT_EN.pdf
There are a lot of THF-51 for sale at aliexpress.....but they probably won't sound good......
I agree with Claudio. In single ended follower mode the Tokins' distortions are more than acceptable to me, with second harmonic dominant. More importantly, they sound lovely.
Here are 1W output into 8 Ohms of my Tokin follower amps. The first two are left and right channels of Hammond 193V loaded 2SK180 follower, Vds 35V Iq 2.5A. The last two are left and right channels of Mu follower common drain THF-51S, Vds 33V Iq 3.0A.
Here are 1W output into 8 Ohms of my Tokin follower amps. The first two are left and right channels of Hammond 193V loaded 2SK180 follower, Vds 35V Iq 2.5A. The last two are left and right channels of Mu follower common drain THF-51S, Vds 33V Iq 3.0A.
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The Tokins as well as the Sony VFETs in common source mode have much higher distortion, similar to single ended triodes. I have had Tokins and VFETs in common source mode previously, but as soon as I heard them in common drain mode, I was won over. Definitely common drain sounded better to me.