Anyone heard the Ming Da MC34AB


Has anyone heard this amp? It is sold by Pacific Valve. http://www.pacificvalve.us/MDMC34AB.html

It is a chinese import. I am considering this amp along with the Rogue Atlas Magnum to go with my Acoustic Zen Adagios and Rogue 99 Magnum pre-amp. I am trying to find a good pairing for the pre-amp and the Adagios.
128x128podolaw
These are highly regarded amps.I have heard one and friends who own them rate them highly compared to high end amps both SS and tube.
35kg with a seperate power supply makes for a very serious EL34 amp with no weak areas.
I have owned this amplifier for several months now. Although it sounds great right out of the box there are things that can be done to greatly improve it's sound. First....junk the Chinese 12AU7s that it comes with. They are not actually 12AU7s anyway. If you measure them they have an output closer to a 12AX7 than a 12AU7. I put in several different 12AU7s before realizing this and lost about half of the volume. A pair of Tele 12AX7s worked wonders. Next.... almost all the "known brand" caps in the unit are fakes. Some of the names on them are even spelled incorrectly! Replace the .22 coupling caps with Vitamin Q PIOs or Russian K-40s. The replace all of the output caps (2uf) which are ridiculously small for their value with equal value, but good quality caps. I used Russian K42s. It was a really tight squeeze, but it can be done. The difference in sound is immediate! I then pulled all of the EL34s and replaced them with Gold Lion Reissue KT66s. With their tapered base they will plug in directly even though the Ming Da has the beauty rings around the sockets that prevent most other tubes from being used. I also purchased some inexpensive octal socket savers that space the tubes up about an inch which will allow you to even run 6550s or KT88s in it if you like. The filament current is almost the same for all the tubes so there is no problem doing it.
Bias is set by measuring from pin 8 to the ground bus on each final tube. Ming Da suggests .33-.35 volts for the EL34s. The KT 66s or KT88s would require more...something in the area or .5-.6 volts. You will be shocked at the improvement that changing the finals and caps makes.
I have the complete schematic of the unit if anyone needs it. Apparently it's a closely guarded secret from Pacific, but Meixing was kind enough to send it to me. Anyone needing it can email me and I'll be happy to send it to them.
Enjoy your amp....Once modded it's a killer!
I just got myself a mc34-ab, my first tube-amp. Tesla NOS EL34's and I use it as a power amp. Sounds wonderful, driving my Zu Druids. Source is a Resolution Audio Opus 21 CD player that includes a good pre. I use the Opus as a DAC, and I feed it from a PC's hard drive through a M2Tech - HiFace (better sounding than using the CD-player!). And also there is a simple monster + MCintosh filtering setup for the AC power. That's my system.

Now it has blown tubes for me two times:
First time - the two mid-sized (driver?) tubes, now replaced to my satisfaction
Second time - the two right-most (seen from the front) EL34's. Cold and non-glowing but still there in the sockets the amp sings even better...

So here are my questions:
Can I remove the corresponding EL34's for the left-channel, to see if sound improves there too, or is that a hazardous experiment

Previous owner had no issue with tubes blowing during two years of ownership, why does tubes blow in my ownership?

FXbill, please if you have the schematic, I'm interested to have a copy, and I'll go for the mods you propose.

BR Zumas
Hi
DO NOT remove tubes from a powered tube amplifier, the heater voltage will shoot up and probably burn the heaters of the remaining tubes.
I suggest that you have the amp checked by a technician.
Owned one for almost 3 years....
NO electrical problems so far and no valve failure
replace the input tubes for NOS, that includes the 6SN7's I use the JJ KT77's as outputs although I may go Genelex 77's next time round or EH EL34's as a standby.
I replaced all the inputs then the blue Ginvina's (EL34) That was like a whole new amp, far clearer and precise mid range, better base and base was tighter, only downside is the top end is still a little harsh on on AAD for my ears on AAD recordings.... I did read reviews on various valves and the comment was that the JJ's tend to be a little 'toppy'... other serious contender for EL34 is the Winged C (svetlana)
Other comment... I often run this amp all day at weekends 8-13 hour stints. The power 'humpty' never gets hot and I can 'rest'my hand on the EL34/77's without getting burnt.
If the valves run this 'cool' may be why my valves are still 'good' after almost 3 years, tested on an AVO VCM 163
THE rolls royce of Tube Testers
One note of caution. Make sure you know where these units came from. Go direct to Meixing factory and find out who is supplying them here. Stay away from ebay and if you buy one here get varification where it came from. The MC2A3 pre amp is arguably the best price to performance piece of gear around. Now they have a new MC300 pre amp that looks even more promising.
hello,fx bill i hope you can send the schematic
of the ming-da mc34-ab
regard,s bertus
to Fxbill: Could you please send me the schematic of the amplifier (wowar4@gmail.com). Will appreciate it a lot!
I have an ancient old email from FxBill with the schematic.
FxBill doesnt seem to be active on various forums recently.
(Miss U Bill!)
Let me see if I can dig it up.