I've got an "Music angel" integrated amp that I got for Free as it didn't work. Turned out the only problem was a blown resistor.
Tubes are barely used at all, less then 20h, nos 6n3p x2 and 6n14p x4(IIRC) writing from my phone so I don't have the Info in front of me.
I'm guessing the output transformers are less then good...but power transformer and tubes might be used for some other project?
I'm mainly thinking about the input tubes and PS transformer.
The, claimed, 2x14W is not enough for my speakers, but I could always use a good preamp.
Tubes are barely used at all, less then 20h, nos 6n3p x2 and 6n14p x4(IIRC) writing from my phone so I don't have the Info in front of me.
I'm guessing the output transformers are less then good...but power transformer and tubes might be used for some other project?
I'm mainly thinking about the input tubes and PS transformer.
The, claimed, 2x14W is not enough for my speakers, but I could always use a good preamp.
This is just me, but I would keep the amp intact and try it on your speakers. You might be pleasantly surprised.
It's not really the watts of the amp you should be concerned about, but the efficiency of your speakers. If they are at least 91 db @ 1 watt, 14 watts will drive them to very satisfactory sound levels.
It's not really the watts of the amp you should be concerned about, but the efficiency of your speakers. If they are at least 91 db @ 1 watt, 14 watts will drive them to very satisfactory sound levels.
I have tried it driving the top half of my dipoles. There's transformer vibrations, and it gets silly hot. AND, as my first child, my daughter is on her way, I can't have equipment that can potentially hurt her.
Btw, when fixing the amp, I measured plate voltage on the input tubes to 333Vdc.
The schematics looks like there's a voltage doubler on it.
I guess even with the doubler in there, the PS trafo could be usefull for some project.
I'll have to measure it to know the HT secondary as I'm way to tired to do any sims or math without getting atleast halv of it wrong lol
Btw, when fixing the amp, I measured plate voltage on the input tubes to 333Vdc.
The schematics looks like there's a voltage doubler on it.
I guess even with the doubler in there, the PS trafo could be usefull for some project.
I'll have to measure it to know the HT secondary as I'm way to tired to do any sims or math without getting atleast halv of it wrong lol
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Starting from such a bad circuit, it would be hard not to improve on it.
As designed, it has a poorly balanced phase splitter and high output impedance.
As designed, it has a poorly balanced phase splitter and high output impedance.
That is about what I thought.
When I tested it with the top half of my dipoles, there was a big difference in volume between the channels.
I was thinking more along the lines of what I could do with the input tubes and PS transformer.
I don't think there's much value in the amp, so it's probably better to salvage usable parts then selling it.
Something is very wrong if you have 333vdc on the input tubes.
I have done a bit of work on the 6P1 version of the Mengyue Mini which is the same as the Aria.
There should be no more than 250v at the top of the anode resistors of the 6N2, and typically around 120v on the anode of the 6N2 itself.
It sounds like you might have a 110v mains version, which may be why it is hot and all the voltages are too high.
These amps can be made to sound good, but it is probably more work than you want for a less-than-10w amp.
I have done a bit of work on the 6P1 version of the Mengyue Mini which is the same as the Aria.
There should be no more than 250v at the top of the anode resistors of the 6N2, and typically around 120v on the anode of the 6N2 itself.
It sounds like you might have a 110v mains version, which may be why it is hot and all the voltages are too high.
These amps can be made to sound good, but it is probably more work than you want for a less-than-10w amp.
Mayday,
You did say preamp. Instead of a doubler go to a 3X or even 4X 1/2 wave parallel multiplier. You will surely have enough headroom to regulate the rail for the hybrid 6SN7 circuit I've uploaded. Use the Chinese power tubes as pass elements in regulators (1/channel).
You did say preamp. Instead of a doubler go to a 3X or even 4X 1/2 wave parallel multiplier. You will surely have enough headroom to regulate the rail for the hybrid 6SN7 circuit I've uploaded. Use the Chinese power tubes as pass elements in regulators (1/channel).
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