7 ms·

Exposure of fake Chinese tube amplifier (2018)

53 points by skanderbm 4y ago

brtkdotse 4y ago
Audiophile equipment and the associated forums are a pretty fun rabbit hole to go down.
gerikson 4y ago
(2018) An online acquaintance informs me this was a "thing" 10-15 years ago.
deleted 4y ago
[deleted]
ratww 4y ago
So, basically the tubes only exist to glow. And to disable the circuit when they're removed. Clever. I'm not surprised. Most of the cheap devices containing tubes I see use a starved plate design, where the tubes are operating well below their ideal range, use a LED for "lightning" (because there's often no AC power to light up the tube filaments), all coupled with $1 reject tubes. Sure, it distorts very easily, so they can be used on music making, but so would a pair of diodes. This is just the next step in the evolution.
- marcosdumay 4y ago
  The passion people have for tube is so much that at some point I expect to see a full 32 bits DSP with low latency ADC and DAC disguised as one.
  - bsder 4y ago
    I've often thought about making tubes that simply glowed but didn't do anything ... Seriously, though, they're called "modeling amps". And many of them sound quite nice.
  - notjulianjaynes 4y ago
    I once circuit bent an old Casio that had a discrete DAC chip, and found I could get some really cool sounding distortion just sticking a 50k pot between the digital in and analog out pins of that chip.
verisimi 4y ago
Well, it looks good! I'm pretty convinced that as long as whatever-it-is looks the part, we don't care. And it could be tech like this, white goods (which are just a branding exercise), real estate even, and then even more ephemeral things like things we are presented with on screens. For most of us, even if we are holding something in our hands, how can we tell if is fake or not?
daniel-cussen 4y ago
You know what happens, though, this is one fake Chinese tube amplifier but what happens if someone makes a fake fake Chinese tube amplifier? At a certain point, like with miomg (either guerilla marketing on a blog, or an actual flash card with merit, or both), you just make the real thing. Like even cheap fake watches have a real 32.768 KHz oscillator inside, which are like 22 cents. That's better than almost all mechanical watches, and it's very hard to fuck that up, because it's the cheapest oscillator by far, and making even a fake watch is actual work, and because hey maybe maybe there's a repeat sale. I'm considering buying this fake Chinese tube amp amplifier to figure out what's up, they used their smarts to fake the tube function, but those are still smarts. Might help with IP protection, ironically.
- ratww 4y ago
  > Like even cheap fake watches have a real 32.768 KHz oscillator inside, which are like 22 cents. That's better than almost all mechanical watches Only as long as the oscillator is really connected. Which, after seeing this article, has a potential of not being the case ;) I like your analogy to copy protection btw
  - daniel-cussen 4y ago
    Well if the oscillator isn't connected it's hard to get a convincing tick. Generally watches are sold actively ticking.
- KennyBlanken 4y ago
  High end watches, like other jewelry, are not about timekeeping but status display, taxless generational wealth transfer, wealth storage, and less-traceable money laundering/payments. I want to give you $100,000 for doing illegal work for me. I buy a $100k watch, hop on a plane, meet you for drinks on a yacht, and say "my friend, you are such a good friend, have my watch!" No taxes, duties, or paperwork. Rinse, wash, repeat. When daddy gives his daughter a several thousand dollar watch, he's not giving her a watch. He's passing along several thousand dollars of family wealth, to be used for both communicating the family's status but also convertible into currency if need be. A bonus is that it likely appreciates in value over time. When daddy gives his mistress some jewelry, he's paying her for services in a way his wife (or her attorneys) can't trace. Before the age of near credit card / digital payment/transfer systems and worldwide near-instant communication, rich travelers would wear a rolex because it served as a sort of compact money storage unit. If you're wealthy and traveling to places wealthy people liked to go and needed help, your rolex serves as proof of resources, or can serve as a payment itself.
JohnJamesRambo 4y ago
It's pretty well known and stated that these are hybrid amps with solid state output stages. Was this not known in 2018? https://www.amazon.com/Nobsound-MS-10D-Tube-Power-Amplifier/dp/B00KFGKKR2 https://www.amazon.com/Nobsound-MS-10D-Tube-Power-Amplifier/... Arent't the tubes just the preamp stage?
- bayindirh 4y ago
  There are serious audio and musical instrument companies which use tubes for pre-amps and solid stage power stages and they're pretty open about it, and some of these are well-loved units. That's not something necessarily bad.
- ratww 4y ago
  They're not preamps. The amp in the article is definitely not an hybrid. Hybrid would mean it uses both Solid State and Tubes to amplify the audio. The tubes are instead only for decorative purposes, and apparently to "turn the circuit on", albeit in a way that is difficult to detect. The article writer used capacitors to simulate the presence of tubes and the amp kept working as normal.
  - JohnJamesRambo 4y ago
    Googling leads me to believe the tubes are used as a buffer stage, which isn't that wild in audio circles, tons of guitar and microphone preamps do this to sweeten the sound or whatever someone wants to call it. I hate fake products, but this one doesn't set off my fraud alarm. And my apologies if other reviews and discussion are wrong about how the tubes are being used in this amplifier, they could be just repeating incorrect facts they hope are right as well.
    - ratww 4y ago
      The person that wrote the forum post made a schematic, you can check it yourself. The tubes are not biased properly and the middle one has the grid grounded and the cathode disconnected, so it doesn't do anything. The third tube is being fed voltage that is tapped from the grid of the first tube, only 2V. That's not only less than their ideal operation point (150V? 200V?), but also probably less than needed for starved plate mode operation. So they're not being used to amplify anything. This means they're not buffers either. I doubt audio would even be passing trough them, since it would get rectified by the third tube which is acting as a diode, which is something you definitely don't want. I'm not familiar with Russian tubes but some of those seem to be power tubes... which makes it even weirder. The article writer suggest that they're used as a timer, probably to simulate how tube amps take a while to turn on. He later "replaced" them with capacitors and the amplifier kept working as intended, which probably means they're being used as diodes to turn the circuit on, for purposes of faking operation. This is all in the forum post. If the schematic is correct, they're not preamps nor buffers.
CoastalCoder 4y ago
I'm curious how long the current state of affairs w.r.t. Chinese fake products sold to Americans will last. So far I'm not aware of any changes to the fundamental drivers that enable / motivate this.
- passivate 4y ago
  What do you mean by "current state of affairs"? There are plenty of reputable products coming out of China. I purchased the Little Dot mk3 tube amp directly from a Chinese manufacturer (no website, direct paypal payment) around 2006 and it still works.
- dsr_ 4y ago
  The word fake is problematic here. I would expect a fake to be something like: - it mimics a particular product but doesn't perform as well (e.g. SD cards that claim to be Kingston 128GB but are actually discard-quality 16GB) - or it looks much like a real brand and product but isn't on close inspection (e.g. COBY vs SONY for quite a while) - or it claims to be a particular thing and isn't (e.g. a tube amplifier that never needs replacement tubes because the tubes aren't connected at all to the LM379 IC actually delivering 6 watts. All of those things are fakes. This is a solid state amplifier with a tube preamp stage, which is... well, if you know what you're buying, I guess you could buy that, but I personally wouldn't. I suppose it looks like a tube power amp, superficially, but the nature of a tube pre-amp and a tube power-amp is to look pretty similar anyway. The bigger general problems, I think, are in Amazon's total lack of care in co-mingling shipments sold on behalf of third-parties, and the general OEM problem where the same equipment has eight different faceplates or cases put on the same board and sold for a range of prices up to two magnitudes different.
  - ratww 4y ago
    > This is a solid state amplifier with a tube preamp stage No it isn't, if you check the schematics in the article you'll see that the tubes aren't biased properly and are mostly disconnected. They can't amplify audio. It's not even a starved plate design (which wouldn't need the 6.3V filament voltage). The circuit is clever enough to stop amplifying as soon as one of the tubes is disconnected, so they're a glorified switch. Which IMO is worse than if the tubes were there only for asthetic purposes.
antiterra 4y ago
Cognitive or psychological effects on the perception of audio are fascinating. I had a friend in sound production tell me that he had the experience of ramping up sliders to show an effect to a client and watching their faces brighten at the improvement. Then, he noticed something was misconfigured and the sliders were doing nothing. That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow.
- Sebb767 4y ago
  > That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. This depends a lot on your setup. In perfect room with 5 digit sound equipment and encoded with a bad encoder? Sure. Good encoder on something like phone speakers, especially with examples not specifically crafted to show weaknesses? Never. Of course there is a lot of in-between, but for most people and setups, mp3 is not the limitation.
- bayindirh 4y ago
  > That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. The half of this ability lies in the audio system being listened to. As we like the say, the performance of something is capped by the weakest link in the system. If you have a good sound source feeding a semi-decent amplifier paired with a good set of speakers, you can feel the sound stage and depth difference between 320kbps MP3 and a CD. However, modern mastering techniques generally maximize loudness and erode some detail, so everything becomes disputable. I have some properly mastered CDs, and listening them blows my ears away every time, others don't do the same because they're compressed for the sake of loudness and they don't sound as spectacular.
- quickthrowman 4y ago
  > That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. You got a link to some independent blind listening test results showing someone has this ability? I’m extremely skeptical of the above claim.
iqkznnft 4y ago
Damn that looks like a high quality forum. I almost wish audio studio was a hobby of mine so I can get something out of that forum.

53 points by skanderbm 4y ago

brtkdotse 4y ago

Audiophile equipment and the associated forums are a pretty fun rabbit hole to go down.

gerikson 4y ago

(2018) An online acquaintance informs me this was a "thing" 10-15 years ago.

deleted 4y ago

[deleted]

ratww 4y ago

So, basically the tubes only exist to glow. And to disable the circuit when they're removed. Clever. I'm not surprised. Most of the cheap devices containing tubes I see use a starved plate design, where the tubes are operating well below their ideal range, use a LED for "lightning" (because there's often no AC power to light up the tube filaments), all coupled with $1 reject tubes. Sure, it distorts very easily, so they can be used on music making, but so would a pair of diodes. This is just the next step in the evolution.

marcosdumay 4y ago
The passion people have for tube is so much that at some point I expect to see a full 32 bits DSP with low latency ADC and DAC disguised as one.
- bsder 4y ago
  I've often thought about making tubes that simply glowed but didn't do anything ... Seriously, though, they're called "modeling amps". And many of them sound quite nice.
- notjulianjaynes 4y ago
  I once circuit bent an old Casio that had a discrete DAC chip, and found I could get some really cool sounding distortion just sticking a 50k pot between the digital in and analog out pins of that chip.

verisimi 4y ago

Well, it looks good! I'm pretty convinced that as long as whatever-it-is looks the part, we don't care. And it could be tech like this, white goods (which are just a branding exercise), real estate even, and then even more ephemeral things like things we are presented with on screens. For most of us, even if we are holding something in our hands, how can we tell if is fake or not?

daniel-cussen 4y ago

You know what happens, though, this is one fake Chinese tube amplifier but what happens if someone makes a fake fake Chinese tube amplifier? At a certain point, like with miomg (either guerilla marketing on a blog, or an actual flash card with merit, or both), you just make the real thing. Like even cheap fake watches have a real 32.768 KHz oscillator inside, which are like 22 cents. That's better than almost all mechanical watches, and it's very hard to fuck that up, because it's the cheapest oscillator by far, and making even a fake watch is actual work, and because hey maybe maybe there's a repeat sale. I'm considering buying this fake Chinese tube amp amplifier to figure out what's up, they used their smarts to fake the tube function, but those are still smarts. Might help with IP protection, ironically.

ratww 4y ago
> Like even cheap fake watches have a real 32.768 KHz oscillator inside, which are like 22 cents. That's better than almost all mechanical watches Only as long as the oscillator is really connected. Which, after seeing this article, has a potential of not being the case ;) I like your analogy to copy protection btw
- daniel-cussen 4y ago
  Well if the oscillator isn't connected it's hard to get a convincing tick. Generally watches are sold actively ticking.
KennyBlanken 4y ago
High end watches, like other jewelry, are not about timekeeping but status display, taxless generational wealth transfer, wealth storage, and less-traceable money laundering/payments. I want to give you $100,000 for doing illegal work for me. I buy a $100k watch, hop on a plane, meet you for drinks on a yacht, and say "my friend, you are such a good friend, have my watch!" No taxes, duties, or paperwork. Rinse, wash, repeat. When daddy gives his daughter a several thousand dollar watch, he's not giving her a watch. He's passing along several thousand dollars of family wealth, to be used for both communicating the family's status but also convertible into currency if need be. A bonus is that it likely appreciates in value over time. When daddy gives his mistress some jewelry, he's paying her for services in a way his wife (or her attorneys) can't trace. Before the age of near credit card / digital payment/transfer systems and worldwide near-instant communication, rich travelers would wear a rolex because it served as a sort of compact money storage unit. If you're wealthy and traveling to places wealthy people liked to go and needed help, your rolex serves as proof of resources, or can serve as a payment itself.

JohnJamesRambo 4y ago

It's pretty well known and stated that these are hybrid amps with solid state output stages. Was this not known in 2018? https://www.amazon.com/Nobsound-MS-10D-Tube-Power-Amplifier/dp/B00KFGKKR2 https://www.amazon.com/Nobsound-MS-10D-Tube-Power-Amplifier/... Arent't the tubes just the preamp stage?

bayindirh 4y ago
There are serious audio and musical instrument companies which use tubes for pre-amps and solid stage power stages and they're pretty open about it, and some of these are well-loved units. That's not something necessarily bad.
ratww 4y ago
They're not preamps. The amp in the article is definitely not an hybrid. Hybrid would mean it uses both Solid State and Tubes to amplify the audio. The tubes are instead only for decorative purposes, and apparently to "turn the circuit on", albeit in a way that is difficult to detect. The article writer used capacitors to simulate the presence of tubes and the amp kept working as normal.
- JohnJamesRambo 4y ago
  Googling leads me to believe the tubes are used as a buffer stage, which isn't that wild in audio circles, tons of guitar and microphone preamps do this to sweeten the sound or whatever someone wants to call it. I hate fake products, but this one doesn't set off my fraud alarm. And my apologies if other reviews and discussion are wrong about how the tubes are being used in this amplifier, they could be just repeating incorrect facts they hope are right as well.
  - ratww 4y ago
    The person that wrote the forum post made a schematic, you can check it yourself. The tubes are not biased properly and the middle one has the grid grounded and the cathode disconnected, so it doesn't do anything. The third tube is being fed voltage that is tapped from the grid of the first tube, only 2V. That's not only less than their ideal operation point (150V? 200V?), but also probably less than needed for starved plate mode operation. So they're not being used to amplify anything. This means they're not buffers either. I doubt audio would even be passing trough them, since it would get rectified by the third tube which is acting as a diode, which is something you definitely don't want. I'm not familiar with Russian tubes but some of those seem to be power tubes... which makes it even weirder. The article writer suggest that they're used as a timer, probably to simulate how tube amps take a while to turn on. He later "replaced" them with capacitors and the amplifier kept working as intended, which probably means they're being used as diodes to turn the circuit on, for purposes of faking operation. This is all in the forum post. If the schematic is correct, they're not preamps nor buffers.

CoastalCoder 4y ago

I'm curious how long the current state of affairs w.r.t. Chinese fake products sold to Americans will last. So far I'm not aware of any changes to the fundamental drivers that enable / motivate this.

passivate 4y ago
What do you mean by "current state of affairs"? There are plenty of reputable products coming out of China. I purchased the Little Dot mk3 tube amp directly from a Chinese manufacturer (no website, direct paypal payment) around 2006 and it still works.
dsr_ 4y ago
The word fake is problematic here. I would expect a fake to be something like: - it mimics a particular product but doesn't perform as well (e.g. SD cards that claim to be Kingston 128GB but are actually discard-quality 16GB) - or it looks much like a real brand and product but isn't on close inspection (e.g. COBY vs SONY for quite a while) - or it claims to be a particular thing and isn't (e.g. a tube amplifier that never needs replacement tubes because the tubes aren't connected at all to the LM379 IC actually delivering 6 watts. All of those things are fakes. This is a solid state amplifier with a tube preamp stage, which is... well, if you know what you're buying, I guess you could buy that, but I personally wouldn't. I suppose it looks like a tube power amp, superficially, but the nature of a tube pre-amp and a tube power-amp is to look pretty similar anyway. The bigger general problems, I think, are in Amazon's total lack of care in co-mingling shipments sold on behalf of third-parties, and the general OEM problem where the same equipment has eight different faceplates or cases put on the same board and sold for a range of prices up to two magnitudes different.
- ratww 4y ago
  > This is a solid state amplifier with a tube preamp stage No it isn't, if you check the schematics in the article you'll see that the tubes aren't biased properly and are mostly disconnected. They can't amplify audio. It's not even a starved plate design (which wouldn't need the 6.3V filament voltage). The circuit is clever enough to stop amplifying as soon as one of the tubes is disconnected, so they're a glorified switch. Which IMO is worse than if the tubes were there only for asthetic purposes.

antiterra 4y ago

Cognitive or psychological effects on the perception of audio are fascinating. I had a friend in sound production tell me that he had the experience of ramping up sliders to show an effect to a client and watching their faces brighten at the improvement. Then, he noticed something was misconfigured and the sliders were doing nothing. That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow.

Sebb767 4y ago
> That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. This depends a lot on your setup. In perfect room with 5 digit sound equipment and encoded with a bad encoder? Sure. Good encoder on something like phone speakers, especially with examples not specifically crafted to show weaknesses? Never. Of course there is a lot of in-between, but for most people and setups, mp3 is not the limitation.
bayindirh 4y ago
> That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. The half of this ability lies in the audio system being listened to. As we like the say, the performance of something is capped by the weakest link in the system. If you have a good sound source feeding a semi-decent amplifier paired with a good set of speakers, you can feel the sound stage and depth difference between 320kbps MP3 and a CD. However, modern mastering techniques generally maximize loudness and erode some detail, so everything becomes disputable. I have some properly mastered CDs, and listening them blows my ears away every time, others don't do the same because they're compressed for the sake of loudness and they don't sound as spectacular.
quickthrowman 4y ago
> That said, there are people who can hear the difference between 320kbps mp3s and uncompressed, because they can sense the faint temporal errors that can make a sound a touch before the sound they should follow. You got a link to some independent blind listening test results showing someone has this ability? I’m extremely skeptical of the above claim.

iqkznnft 4y ago

Damn that looks like a high quality forum. I almost wish audio studio was a hobby of mine so I can get something out of that forum.