^ Might be faked on some models but not others including this one.
It's legitimate to put the signal through a tube stage but still use a class A or A/B output.
The more biased towards class A the A/B output is, the more heat the transformer is going to produce, so a raised area over it with vent slits, is not a bad design decision considering otherwise the space on the back would be wasted anyway, not like you want to put something on the rear of the amp where the heat is coming out.
This dude did a teardown. The black cover is all show. The preamp section is in fact (valve) vacuum tubes... The output stage is Solid State..Looks like Class A/B.
A "typical" stereo 2 channel tube Amp will have 3 transformers. One for the Power supply (plate voltage B+ and LV filaments) and one balancing transformer for each channel, high impedance to low. ~8ohms.
^ I saw that video, and that dude, did not understand what I already mentioned, the benefit of having a raised chamber for not only heat rising but also to prevent people from putting/stacking something over it, not that it would be rational to do that since the otherwise tallest objects are the tube shields.
Output being A/B, is not a deal breaker to me at this price point. Depends on what you're looking for, you can get tube warmth and ***ociated pleasing distortion values and then boost the output with an IC output fine, and cheaper, so as always ideals cost a premium and another thought that crossed my mind was that the extra space above the transformer could allow mounting a toroidal replacement... room to mod.
You won't find anything at the $150 or lower price point that doesn't have room for improvement if you're bored and want to pour your money into it as a hobby.
Personally I have no desire for tubes, but I have some quirks myself that others don't share in amp design (I've built my own) so if someone wants tubes and is happy with the outcome, fair is fair.
This dude did a teardown. The black cover is all show. The preamp section is in fact (valve) vacuum tubes... The output stage is Solid State..Looks like Class A/B.
A "typical" stereo 2 channel tube Amp will have 3 transformers. One for the Power supply (plate voltage B+ and LV filaments) and one balancing transformer for each channel, high impedance to low. ~8ohms.
Sadly people still fall for this scam. A solid state class A is not the same as TUBE. Clearly these tubes are for decor. For $150 people just better off go with a cheap receiver.
Sadly people still fall for this scam. A solid state class A is not the same as TUBE. Clearly these tubes are for decor. For $150 people just better off go with a cheap receiver. - dennis007
Not just for decor, they are a functional part of the amp..(Pre-amp)
This is what you would call an "Integrated Amp"
^ I saw that video, and that dude, did not understand what I already mentioned, the benefit of having a raised chamber for not only heat rising but also to prevent people from putting/stacking something over it, not that it would be rational to do that since the otherwise tallest objects are the tube shields.
Output being A/B, is not a deal breaker to me at this price point. Depends on what you're looking for, you can get tube warmth and ***ociated pleasing distortion values and then boost the output with an IC output fine, and cheaper, so as always ideals cost a premium and another thought that crossed my mind was that the extra space above the transformer could allow mounting a toroidal replacement... room to mod.
You won't find anything at the $150 or lower price point that doesn't have room for improvement if you're bored and want to pour your money into it as a hobby.
Personally I have no desire for tubes, but I have some quirks myself that others don't share in amp design (I've built my own) so if someone wants tubes and is happy with the outcome, fair is fair. - dave_c
Sorry....That h- u m p doesn't work for me...
They are not IC output chips..(TDAxxx.. or LM3***6, etc....) Notice the discrete output transistors...TO-220-something.
I also noticed the filtering caps are mounted on the bottom of the board. I suppose at these power levels the heat on those electrolytic caps may not be an issue, but I would have mounted them on top..
The transformer is just fine for the rated output power. They can handle quite a lot of heat with just air vents.
Pas--sive cooling will do. However, the transistor heatsinks look tiny. A low-speed, low noise fan would be my choice for extra cooling....Or more alluminum.
Talking audio is like talking about politics, or religion.:)
(or Cordless TOOLS....)
Comments & Reviews (9)
It's legitimate to put the signal through a tube stage but still use a class A or A/B output.
The more biased towards class A the A/B output is, the more heat the transformer is going to produce, so a raised area over it with vent slits, is not a bad design decision considering otherwise the space on the back would be wasted anyway, not like you want to put something on the rear of the amp where the heat is coming out.
A "typical" stereo 2 channel tube Amp will have 3 transformers. One for the Power supply (plate voltage B+ and LV filaments) and one balancing transformer for each channel, high impedance to low. ~8ohms.
https://www.youtube.com/watch?v=4BppEjYb7PM
Output being A/B, is not a deal breaker to me at this price point. Depends on what you're looking for, you can get tube warmth and ***ociated pleasing distortion values and then boost the output with an IC output fine, and cheaper, so as always ideals cost a premium and another thought that crossed my mind was that the extra space above the transformer could allow mounting a toroidal replacement... room to mod.
You won't find anything at the $150 or lower price point that doesn't have room for improvement if you're bored and want to pour your money into it as a hobby.
Personally I have no desire for tubes, but I have some quirks myself that others don't share in amp design (I've built my own) so if someone wants tubes and is happy with the outcome, fair is fair.
A "typical" stereo 2 channel tube Amp will have 3 transformers. One for the Power supply (plate voltage B+ and LV filaments) and one balancing transformer for each channel, high impedance to low. ~8ohms.
https://www.youtube.com/watch?v=4BppEjYb7PM - Super_Flubber
This is what you would call an "Integrated Amp"
Output being A/B, is not a deal breaker to me at this price point. Depends on what you're looking for, you can get tube warmth and ***ociated pleasing distortion values and then boost the output with an IC output fine, and cheaper, so as always ideals cost a premium and another thought that crossed my mind was that the extra space above the transformer could allow mounting a toroidal replacement... room to mod.
You won't find anything at the $150 or lower price point that doesn't have room for improvement if you're bored and want to pour your money into it as a hobby.
Personally I have no desire for tubes, but I have some quirks myself that others don't share in amp design (I've built my own) so if someone wants tubes and is happy with the outcome, fair is fair. - dave_c
They are not IC output chips..(TDAxxx.. or LM3***6, etc....) Notice the discrete output transistors...TO-220-something.
I also noticed the filtering caps are mounted on the bottom of the board. I suppose at these power levels the heat on those electrolytic caps may not be an issue, but I would have mounted them on top..
The transformer is just fine for the rated output power. They can handle quite a lot of heat with just air vents.
Pas--sive cooling will do. However, the transistor heatsinks look tiny. A low-speed, low noise fan would be my choice for extra cooling....Or more alluminum.
Talking audio is like talking about politics, or religion.:)
(or Cordless TOOLS....)
here are two projects on my list
https://www.amazon.com/dp/B08D6CB83J/?
AND THIS ONE... I'll need to find matched original Moto 2n3055's tho....
https://www.amazon.com/dp/B083XWFVKW/?
TGIF!
NE5553, LM386.+High-quality caps.
Thank you!