Meng Yue Mini schematic?

[rotaspec]

Anyone have a schematic for this little Chinese EL84PP clone?
I just picked one up on an auction and before I start tracing it out, I thought I would try here first.

Thanks, Gary

[DHT112A]

Don't know if this is it since yours has EL84 but here is shot

[rotaspec]

Originally Posted by DHT112A

Don't know if this is it since yours has EL84 but here is shot

No mine has 6P1-14 or somesuch (haven't actually got the amp yet, its in transit to me), so thanks for the pic. I called it a EL84PP clone because I wasn't sure of the actual tubes they use.
I also found an article from Audio Express on rebuilding this amp.
Apparently they are a bit variable in their construction quality (and safety ), so some basics will come before any mods.

Gary

[Trebla]

This may be close.

Aria 6P14 makeover.

I just got one too, but haven't had time to work out the circuit yet.
I suspect they vary a bit anyway.

The build quality is as you might expect. On mine, only three of the four rubber feet actually touch the shelf, because there is a twist in the chassis. Not too bothered for the price, as i'll be re housing it anyway. There doesn't seem to be a chassis earth so take care.

However, it sounds much nicer than i expected, even with the Chinese tubes.
Took an hour or so to settle in.
Mine arrived with 6n1 tubes instead of 6n2, which was handy as i had some Russian 6n1p-ev tubes in stock. Got some more Russian 6n14p on the way.
I have to wonder if its worth the bother of building amps any more.

[kevinkr]

Originally Posted by Trebla

This may be close.

Aria 6P14 makeover.
<snip>
I have to wonder if its worth the bother of building amps any more.

I guess not if the only thing you really want to do is rehash the same old tired work of others..

Personally I think one of these might be fun to play with, (they're rather like the stuff I played with 30yrs ago) but I'd rather build and debug one of my own designs..

Where is the challenge here?

[rotaspec]

Originally Posted by kevinkr

Where is the challenge here?

What I wanted was a reasonably nice sounding amp that is aesthetically and financially acceptable to the rest of the household.
My budget stretches to the cost of a chassis punch (which is what this amp cost me), and if the result after mods is still below what I want, I have some chance of selling it on. Given my abilities to produce something that looks nice enough to take to market are zero, I think this is a good option.
I like a challenge too, but unfortunately, I am not in a financial position to afford to build the equipment of my dreams, and therein lies the challenge.

Gary

[kevinkr]

Originally Posted by rotaspec

What I wanted was a reasonably nice sounding amp that is aesthetically and financially acceptable to the rest of the household.
My budget stretches to the cost of a chassis punch (which is what this amp cost me), and if the result after mods is still below what I want, I have some chance of selling it on. Given my abilities to produce something that looks nice enough to take to market are zero, I think this is a good option.
I like a challenge too, but unfortunately, I am not in a financial position to afford to build the equipment of my dreams, and therein lies the challenge.

Gary

All good reasons not hinted at in your previous post, however with some very judicious scrounging at electronic surplus dealers, radio shows, and amateur radio flea markets you would be surprised at what you can put together for short money. I didn't always have money to burn on this hobby and still managed to scratch build a lot of pretty good things from recycled parts.

Making things look good is a matter of practice, patience, a few tools, and a plan - perhaps the most important item of all. I'm quite challenged in both the mechanical skill (other than cars??) department and am also not the most patient person. A lot of my stuff looks amateurish compared to what I see here and elsewhere...

That amplifier is a good place to start though under the circumstances I think, and you can have some fun tweaking it.

[Ian444]

Kevin,

In the USA you can build an amp pretty cheap even with new iron e.g. Edcor or Hammond. But iron is heavy and it costs a lot for freight if you want to buy the same iron from another country. A fully built amp from China may cost say $220-$280 shipped (talking 6P1 or EL84). We can barely build a small amp here in Australia from scratch for twice that. Ah thems the breaks

Ian.

[Trebla]

Yep, it's the cost of the iron that stops me from being a prolific builder.
My newly aquired Chinese amp cost less than a decent mains TX, and performs annoyingly well.
Meanwhile my pride and joy homebrew SE amp has been relegated to the spare room.

The schematic i posted earlier turns out to quite different to my amp.

[Ian444]

I got inspired by the Suppo Audio circuit and applied it to a Mengyue Mini 6P1 amp. The result was spectacular, very good indeed, especially after replacing the 6N2 with 6N1P-EV Russian tubes. The difference was like night and day.

To do the conversion, I removed all the resistors except B+ and output tube cathode resistors from underneath the PCB. Then refitted the PCB into the amp and soldered all the new parts onto the copper side of the PCB, no traces needed cutting but 2 caps are lifted at one end with a jumper wire to attach them to the correct part of the circuit. This approach is a solution to the difficulty of tweaking these amps, now almost everything is accessed with just the bottom cover removed. My amp was the schematic in the 2nd post of this thread.

Trebla, I bought my amp a couple of years ago, does your new amp use a similar topology or did they change it for some other type?

Ian.