Burned again, Chinese gear not built to schematic...

Dr. Ears

Super Member
I have my second Chinese made integrated amplifier unable to be repaired because it wasn't built to the schematic. The first one featured 845 output tubes, the second one featured 211 output tubes.
I love how they sounded with the coupling caps rolled.
My next integrated will be made in Japan and upgraded by Victor Kung of vkmusic.ca.
Victor is a CPA by trade, high-end audio is his side gig. He knows what he is doing and he is a very nice guy,
who prices his gear very fairly.
Meanwhile, I am enjoying a Scott r77s, made in Belgium and purchased on "Letgo" for $30.
Buying vintage may make more sense than new Chinese gear because at least you know that it can be repaired and upgraded.
 
A good tech should be able to repair your amplifiers even with no schematic.
Yes, but at a price that makes it not worthwhile.
I am going to try an inexpensive tubed preamp or tube buffer with my Scott r77s.
I own hundreds of 6SN7's and 6SN7 substitutes, about 100 6SL7's and more than 100 6N3 / 5670 / 2C51 / 396a, so it makes sense for me to try and find away to use these tubes.
I did see the 6N3 version of the $31 wonder on Amazon for $61 and believe that the 6N3's will sound better than the 6J1's and their equivalents
 
It's unclear to me how you can boldly claim that the amp wasn't built to the schematic. If the unit you have doesn't match the schematic you have, that simply means you have the wrong schematic.
 
Hmmm? Burned once, twice shy didn't apply here?

Oft times, even with other types of gear, this formula holds true. That "Throw Away" attitude is foremost in the minds of those...over there with the profit margin in mind.

Strange how "vint" becomes "mint" in the long run.


Q
 
Maybe if you provided any details at all about the “unable to be repaired” amp, someone could offer advice. Or is the purpose of the thread just to dump on Chinese made products?
 
...Or is the purpose of the thread just to dump on Chinese made products?...

He's been burnt twice on Chinese amplifiers and he's posting his understandable frustration after two technicians told him the recent one wasn't built to the schematic supplied.

Paying for technician's time to draw out the schematic and then paying for more time to fix the problem makes it not worth it. I don't think he'll make the same mistake again with ChiFi.
 
I think there is something people don’t understand, if you haven’t spent any time in China you won’t understand. The Chinese are famous for subcontracting out to cottage industries to save money. They will sub-out 500 hundred units at a time, supplying the external parts assemblies. Then they are famous for making things as cheap as possible. Don’t get me wrong, when they first start selling a product, it’s a good time to buy the equipment. But as time goes on they look to squeeze every Yuan they can from the process then sell everything off to someone else who tries to make everything even cheaper trying to make a profit off the products past reputation. Then there is a good chance that the internal components are copy-cat black market components. I’d say, buy at your own risk and maybe you might be lucky enough to find a Chinese company that makes a great product. There are new start up companies happening all over the world.....
 
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But as time goes on they look to squeeze every Yen they can from the process then sell everything off to someone else who tries to make everything even cheaper trying to make a profit off the products past reputation.
Actually, Japan uses the Yen. China's currency is the RMB.
 
Maybe if you provided any details at all about the “unable to be repaired” amp, someone could offer advice. Or is the purpose of the thread just to dump on Chinese made products?
I thoroughly enjoyed both units, but I will try an integrated from Japan next.
 
Japan uses the yen, China uses the yuan....

Most of us that have lived in Asia pronounce it the same way and write it the same !!!
Put me proudly in the minority group that has lived in Asia and not lumped everything Asian as the same. The value of Japan's yen and China's RMB are dramatically different, and seems odd that the majority of people would strive to pronounce and write them the same intentionally leading to confusion.
 
in decades of reading about this - there's not a single manufacturer (cars, audio, PC/Mac/Unix/Linux OS) that
does not have production changes and therefore changes to the "schematics" as a specific example
for audio.

Witness the AK threads on Marantz, etc specifically parts/schematic/production changes
Marantz Service Manual Error Thread:
http://www.audiokarma.org/forums/index.php?threads/marantz-service-manual-error-thread.375907/

not built to schematic. what exactly? R100 not 1/2 watt, not 47K, not CF/MF/CC/etc?
wrong tubes, wrong grid leak, wrong plate resistance, wrong cathode biasing cap value?
and what exactly was the problem that necessitated a repair?

post some details and we can either
1. get you an accurate schematic
2. rate your two technicians
3. energize you in schematics, DIY, improvements, and Better SQ
4. fix whatever might be the problem, or make it more reliable.

it's an act of love to learn more about what you buy, an extension of buying
a new car and opening the hood for everyone to ooh...ahhh.

if you buy Japanese tube equipment, be prepared. get yourself access to online
versions (cheaper than buying the magazine) of MJ and all the various websites
on Japanese tube amps, and the secret sauce sites.

for MJ, if you don't read Japanese, you would do much better by being able to
read schematics. there are several DIY projects each month. I stopped reading
after their 100th anniversary issue but I refer to many articles for their genius -
my favorite is one project using an opamp as a driver for a PP amp.

I have (tube headphone amp, DAC with tube buffer, 829-tetrode pp amp,
two el34 pp amps, the cheapy appj low power amp, the nobsound ns-13)
all Chinese and all running for the last ten years or so without a single failure.

so it would be super interesting for me to hear about what units you have
and for the rest of us to help you fix them. we can search and review
those units (yours would likely not be the only ones in north America)
 
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My next integrated will be made in Japan and upgraded by Victor Kung of vkmusic.ca.
Victor is a CPA by trade, high-end audio is his side gig. He knows what he is doing and he is a very nice guy,
who prices his gear very fairly.

Bought an Elekit TU-8100 kit amp from him early last year and was happy with the experience. The kit is high quality.
 
Put me proudly in the minority group that has lived in Asia and not lumped everything Asian as the same. The value of Japan's yen and China's RMB are dramatically different, and seems odd that the majority of people would strive to pronounce and write them the same intentionally leading to confusion.

Yen does not equal Yuan. Yes, the official term for Chinese currency is the renminbi, but the basic unit is the yuan (元) and that term is used colloquially a lot in China. Just because the words yen and yuan sound similar does not mean those using them assume they are the same. As someone who lived in China, yuan is a very common term. Also, there is no rule that currencies have to have drastically different sounding names, otherwise we need to sort out why the US, Canada, Australia, and New Zealand all use the dollar when their dollars are not the same.

Finally, if you still doubt about the Chinese currency, you can find the references to the yuan in the first couple sentences here: https://en.wikipedia.org/wiki/Renminbi
 
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beyond @judsonw , the term yuan is similar to dollar, yet everyone uses
Australian dollar, New Zealand dollar, Canadian dollar and no one mistakens
one for the other.

the yen and the yuan use radically different Japanese/Chinese characters (respectively)
and if anyone confuses one for the other, I suggest character "Y" dyslexia and suitable
non-medical (permanent I might say) treatment (aka solution) by using, instead, the word:

Yowza.
 
in decades of reading about this - there's not a single manufacturer (cars, audio, PC/Mac/Unix/Linux OS) that
does not have production changes and therefore changes to the "schematics" as a specific example
for audio.

Witness the AK threads on Marantz, etc specifically parts/schematic/production changes
Marantz Service Manual Error Thread:
http://www.audiokarma.org/forums/index.php?threads/marantz-service-manual-error-thread.375907/

not built to schematic. what exactly? R100 not 1/2 watt, not 47K, not CF/MF/CC/etc?
wrong tubes, wrong grid leak, wrong plate resistance, wrong cathode biasing cap value?
and what exactly was the problem that necessitated a repair?

post some details and we can either
1. get you an accurate schematic
2. rate your two technicians
3. energize you in schematics, DIY, improvements, and Better SQ
4. fix whatever might be the problem, or make it more reliable.

it's an act of love to learn more about what you buy, an extension of buying
a new car and opening the hood for everyone to ooh...ahhh.

if you buy Japanese tube equipment, be prepared. get yourself access to online
versions (cheaper than buying the magazine) of MJ and all the various websites
on Japanese tube amps, and the secret sauce sites.

for MJ, if you don't read Japanese, you would do much better by being able to
read schematics. there are several DIY projects each month. I stopped reading
after their 100th anniversary issue but I refer to many articles for their genius -
my favorite is one project using an opamp as a driver for a PP amp.

I have (tube headphone amp, DAC with tube buffer, 829-tetrode pp amp,
two el34 pp amps, the cheapy appj low power amp, the nobsound ns-13)
all Chinese and all running for the last ten years or so without a single failure.

so it would be super interesting for me to hear about what units you have
and for the rest of us to help you fix them. we can search and review
those units (yours would likely not be the only ones in north America)

I have put the issues behind me, but as I recall, there were too many resistors in one unit.
I would buy Chinese again, but next time have a tech check that it was built to the schematic before putting it into service.
 
I have my second Chinese made integrated amplifier unable to be repaired because it wasn't built to the schematic. The first one featured 845 output tubes, the second one featured 211 output tubes.
I love how they sounded with the coupling caps rolled.
My next integrated will be made in Japan and upgraded by Victor Kung of vkmusic.ca.
Victor is a CPA by trade, high-end audio is his side gig. He knows what he is doing and he is a very nice guy,
who prices his gear very fairly.
Meanwhile, I am enjoying a Scott r77s, made in Belgium and purchased on "Letgo" for $30.
Buying vintage may make more sense than new Chinese gear because at least you know that it can be repaired and upgraded.

I would buy Chinese again, buy have a tech check that it was built to the schematic before putting the unit into service.
 
?

too many resistors? how so? even if they are paralleled (dissipation) or series
(for higher voltage limits) they are good, legitmate EE reasons.

how about buying that next unit and not having the technician look for problems
but to have him/her change the schematic to what is in the unit, thereby matching
the schematic to the working operational/functional characteristics.

non-matching schematics and units do not have any relationship to reliability or
SQ. it may be the junior trainee assigned to "update" the designer's original
schematic did not have the understanding of what a good accurate schematic
should be.

you are the first person to buy an audio device based on accurate matching
schematic.

you may be onto something here but I would have to ask - how does one
verify the accuracy of the schematic inside a large ASIC or PLA in
some of our current modern offerings.
 
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