|
|
Post by mgbpuff on Sept 2, 2021 8:20:42 GMT -5
AGD is making a 85 watt monoblock GANFET 'tube amp'. GANFETs are the latest rage in power semi-conductors (or are they tubes ?  ). See for yourself -  And here are the 'tubes' (about $2000 apiece).  |
|
|
|
Post by ttocs on Sept 2, 2021 8:39:02 GMT -5
I spoke with the owner at AXPONA and asked about the "tube". It took several minutes of trying to ask the same question many different ways to pin down the fact that it's not a "tube under vacuum", but he was adamant that it "is" a tube.
It's a nice design, and it really did sound great. But it's not a tube amp.
|
|
|
|
Post by 405x5 on Sept 2, 2021 9:17:57 GMT -5
AGD is making a 85 watt monoblock GANFET 'tube amp'. GANFETs are the latest rage in power semi-conductors (or are they tubes ? ). See for yourself - View Attachment And here are the 'tubes' (about $2000 apiece). View AttachmentHonesty and proof that solid state rules, along with an eye candy display to keep the tube crowd happy! I was thinking, somebody could get rich by producing an “old electronics” aerosol spray to go along with such a package. (I love that smell of an ancient stereo!) |
|
|
|
Post by monkumonku on Sept 2, 2021 9:42:13 GMT -5
I spoke with the owner at AXPONA and asked about the "tube". It took several minutes of trying to ask the same question many different ways to pin down the fact that it's not a "tube under vacuum", but he was adamant that it "is" a tube. It's a nice design, and it really did sound great. But it's not a tube amp. Well now, there are lots of varieties of "tubes" out there. Here's just three examples (the last one is a tube, of the type "R" variety):    |
|
DYohn
Emo VIPs 
Posts: 18,364
|
Post by DYohn on Sept 2, 2021 9:52:59 GMT -5
It's a solid state circuit enclosed in glass for appearance's sake. Whatever floats your boat.
|
|
KeithL
Administrator 
Posts: 9,976
|
Post by KeithL on Sept 2, 2021 10:32:05 GMT -5
Gallium Nitride FETs... now being used in some newer Class-D amps....
So I guess it's a "tube" - just not a VACUUM tube.  (Putting it under vacuum would reduce the available conductive and convective cooling and wouldn't have any real benefit.)
I spoke with the owner at AXPONA and asked about the "tube". It took several minutes of trying to ask the same question many different ways to pin down the fact that it's not a "tube under vacuum", but he was adamant that it "is" a tube. It's a nice design, and it really did sound great. But it's not a tube amp. |
|
|
|
Post by audiobill on Sept 2, 2021 18:13:49 GMT -5
So in these do electrons float gently from filament to plate, or crawl through shredded glass (silicon)?
|
|
|
|
Post by MusicHead on Sept 2, 2021 21:14:39 GMT -5
So in these do electrons float gently from filament to plate, or crawl through shredded glass (silicon)? Technically, neither. No Silicon was harmed making GaN FETs 😁. |
|
|
|
Post by donh50 on Sept 3, 2021 8:29:01 GMT -5
Let's take the latest technology, wrap it in a bulb that lets it heat up more, and make it sound like 100-year-old designs because, you know, vintage is better.
Audio is a strange world.
|
|
KeithL
Administrator
Posts: 9,976
|
Post by KeithL on Sept 3, 2021 12:31:24 GMT -5
OK.... let's be honest here.... those electrons DO NOT float gently from filament to plate in a vacuum tube...
The electrons start out on the cathode... where they are heated... until they get so hot that they boil off into the charge cloud... There most of them mill around aimlessly for a while until the attraction of the charge on the plate starts to pull them in... So they accelerate towards the plate for a while... until blocked by the proximity of the opposing charge on the grid...
The ones that manage to squeeze past the grid accelerate for a while longer... Before being brought to a sudden stop when they slam into the plate... It's more like a ride on a rocket sled than like "floating gently"...
If I was an electron I think I'd find a nice smooth path through a block of glass much more comforting....
And, strictly speaking, since these are Class-D amps, the electrons jump through the switches in groups... And the main semiconductor switches are gallium nitride and not the rather more prosaic silicon...
I also must admit that, while I've never heard these, and don't have any desire to listen to real tubes, I do think these are rather cute... in a sort of 60's diner, chrome trim, retro sort of way.
So in these do electrons float gently from filament to plate, or crawl through shredded glass (silicon)? |
|
). See for yourself - 
And here are the 'tubes' (about $2000 apiece). 
