Very curious, can anyone comment on the sound and quality of the Ming Da MC-3008-A2 40W Mono Blocks from Pacific Valve?...
I can't find any reviews. The tube topology is (2)12AX7, (2)12AU7, (2)300B, (2)805 tubes. I don't have a schematic, but is it a good design with decent OPT?...
I am going to run it as a integrated amp with a Cambridge Audio CDP 640v2. Speakers are Paradigm S40 v3.
Thanks Guys!
I can't find any reviews. The tube topology is (2)12AX7, (2)12AU7, (2)300B, (2)805 tubes. I don't have a schematic, but is it a good design with decent OPT?...
I am going to run it as a integrated amp with a Cambridge Audio CDP 640v2. Speakers are Paradigm S40 v3.
Thanks Guys!
Hello,
If you still want info about this amp Lampizator site have a nice review about this SET, scroll down the page:
ming-da
I also like this Ming-DA 805 SET looks a great amp, lots of potential for good sound.
I got this information in contact with Mr.Lukasz:
1- What security protection this amp have(B+ fuses, micro process etc)??
No B+ fuse, no micro. It is basic.
2- This amp are zero neg.feedback or use alot of NFB ??
It has some feedback, I dont know how much but in my opinion it is not necessary at all.
3- What is the Net Weight of this monoblock ??
I dont know but maybe USA quotes gross with packing.They are heavy, I think 25 not 30 Kilos.
I would use 300B from Electro Harmonic Gold series (russia). Best bang for the buck.
The 805's are good tubes. It is VERY good value amp and it is very well made. First class really/.
Lukasz
I got this information in contact with the Ming-Da lady:
1- The heating of the four tubes are AC or DC?
.. The heating for 805: DC, 300B or 2A3C: DC, 12AX7 and 12AU7: AC.
2- How is the BIAS adjustment of the 300B and 805 tubes??
.. You can use a multimeter to contact the 1 ohm/5W resistor near 805 tube and then
adjust the 33K adjustable resistor to make the multimeter to show 0.1Volt
3- This amp are zero NegativeFeedback? Or how much NFB it has?
.. There is Negative Feedback and the NFB could only be known after it is tested.
4- The site index - Pacific Valve are your authorized dealer??
.. Yes, Pacificvalve is our authorized dealer and you won't get a fake one from him.
5- On a PacificValve YouTube.com video the 805 cathode start emit light instantly after
power on, in a clear lighted room. I wonder If this amp has soft start?
.. Yes, the amp has soft start.
6- PacificValve say the MC3008(2A version) they sell are a special and better version for the US market.
This is true??
.. MC3008-A is already very good.
7- This MingDA MC3008A amp is a safe amp when a tube fail on the fly?
.. It is safe. If there is something wrong with the tubes, the biggest problem is no sound from amp.
The amp will not burn you.
8- Iam ask it because I was told this amp have no one security on all the tubes, nor B+ fuses,
no Short-Circuit fuses, no micro-processed monitoring etc... Do you confirm this?
.. The fuse in the power plug will disconnect the machine by itself if a short-cut happens in the amp.
When the amplifier is working, please do not leave for a long time and there should be no combustible
goods near the amp.
9- If the amp had no security, I wonder if I can order it with some safe guards as B+ fuses, soft start etc??
.. Yes, they can be installed.
As I said above, if you have any questions, please feel free to contact me.
MC3008-A is fantastic. Maybe you can have a try.
I wish say a very special thanks to Mr.Lucasz Fikus and Ms.Suena from Ming-Da factory who kindly take time to send me this very detailed infos.
Gustavo
There is a new version of this nice amp on the USA distributor PacificValve:
Pacific Valve & Electric Company Ming Da MC 3008B Mono Blocks
It have new circuits, Mundorf and Jensen capacitors, etc... and the price has not increased ( a rare feature).
This new model are named MC3008-B
Pacific Valve & Electric Company Ming Da MC 3008B Mono Blocks
It have new circuits, Mundorf and Jensen capacitors, etc... and the price has not increased ( a rare feature).
This new model are named MC3008-B
I recently bought the 2012 version of the amps (stainless steel chassis, not aluminum). I like them. The amps feels solid and sounds very good with stock tubes and without any mods. 300B + 805/FU5 is very musical and dynamic combination.
The amps were packed good and the bigger tubes and the tube covers came in a separate box.
I received FU-5 + Jinvina 300B tubes. There was no information regarding the 12AX7/12AU7 tubes which way they should inserted (which one goes to left/right socket), at least in a language I understand.
The polymer capacitors inside are mainly Jinvina brand also, which is Mingda's own brand.
Mingda also makes the OPT's (and power transformers) they use. I read somewhere the core material is advertised to be imported from Japan.
The power transformer is relatively quiet but not totally silent in my electricity line. It might be partially potted since I could not remove the cover. It's top also sounds "full" when I knock it, but the sides do not, which might hint that the trafo is partially potted. If one wishes one could fully pot it by pouring in more epoxy from the hole where the wires go inside the amp. I'm considering it, I cannot remove the cover anyway so no harm potting it fully. By the way, what do you guys think about using "basic" (normally thermally conductive, not super conductive) epoxy in potting, does it raise the power transformers temperature compared to partial potting? Or lower it?
The OPT's cover was not just for the looks, the OPT is an almost tight fit inside the cover! It's core's dimensions are (W*H*D) 11,5*10*7cm, quite a big fella. The windings are impregnated and the core/everything is wholly covered in an epoxy layer. It feels very solid and heavy. The amp is quite back-heavy when you lift it since propably 70-80% of the ~25kg mass (have not measured) comes from the transformers.
Some cap mods are propably coming at some point in the most critical spots. I might bypass the global negative feedback loop also or put it behind a switch. I'm interested to hear how they sound then based on Lampizator's comments. I feel the base is very good to do slight modding. Point to point layout is superb, easy to change components.
edit. The amp also supports the non-capped 805 tubes also as stock. The "pearl string" is connected directly to the tube socket pin.
Some pictures:
The amps were packed good and the bigger tubes and the tube covers came in a separate box.
I received FU-5 + Jinvina 300B tubes. There was no information regarding the 12AX7/12AU7 tubes which way they should inserted (which one goes to left/right socket), at least in a language I understand.
The polymer capacitors inside are mainly Jinvina brand also, which is Mingda's own brand.
Mingda also makes the OPT's (and power transformers) they use. I read somewhere the core material is advertised to be imported from Japan.
The power transformer is relatively quiet but not totally silent in my electricity line. It might be partially potted since I could not remove the cover. It's top also sounds "full" when I knock it, but the sides do not, which might hint that the trafo is partially potted. If one wishes one could fully pot it by pouring in more epoxy from the hole where the wires go inside the amp. I'm considering it, I cannot remove the cover anyway so no harm potting it fully. By the way, what do you guys think about using "basic" (normally thermally conductive, not super conductive) epoxy in potting, does it raise the power transformers temperature compared to partial potting? Or lower it?
The OPT's cover was not just for the looks, the OPT is an almost tight fit inside the cover! It's core's dimensions are (W*H*D) 11,5*10*7cm, quite a big fella. The windings are impregnated and the core/everything is wholly covered in an epoxy layer. It feels very solid and heavy. The amp is quite back-heavy when you lift it since propably 70-80% of the ~25kg mass (have not measured) comes from the transformers.
Some cap mods are propably coming at some point in the most critical spots. I might bypass the global negative feedback loop also or put it behind a switch. I'm interested to hear how they sound then based on Lampizator's comments. I feel the base is very good to do slight modding. Point to point layout is superb, easy to change components.
edit. The amp also supports the non-capped 805 tubes also as stock. The "pearl string" is connected directly to the tube socket pin.
Some pictures:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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Thanks for posting, very nice fotos.
I suggest you disconect the output power VU meter a non audiophile device.
I also suggest you dont complete the level of the power trafo pot.
The new epoxy material may not combined and unite with the epoxy already put by the factory and it can even not be epoxy.
A new placement of epoxi also can not be good by the internal trafo wiring.
It also will change the resonance freq of the trafo vibrations.
Fact is that the MingDa OPTs have very good sound quality.
They managed to make a very good sound OPT with a unusual lamination steel.
The factory site inform the trafos use Z11 and H18 lamination.
I suggest you disconect the output power VU meter a non audiophile device.
I also suggest you dont complete the level of the power trafo pot.
The new epoxy material may not combined and unite with the epoxy already put by the factory and it can even not be epoxy.
A new placement of epoxi also can not be good by the internal trafo wiring.
It also will change the resonance freq of the trafo vibrations.
Fact is that the MingDa OPTs have very good sound quality.
They managed to make a very good sound OPT with a unusual lamination steel.
The factory site inform the trafos use Z11 and H18 lamination.
I will propably leave the power trafos as is. Audiophile or not, I like the looks VU meters
. At least for now. I have not decided yet what mods i will make. I tried disabling the negative feedback loop (which seems to be approx. 10dB since the gain increased ~that much). I will have to think about removing the first tube or increasing the local feedback around the 805 to make the gain more acceptable when the feedback is disabled. Maybe increasing local feedback would be better since the output impedance is propably very high based on the frequency response differences (in acoustic domain) I measured.Somebody have an idea for the local negative feecback around the 805? 5-100k ohm resistor from OPT's 8ohm tap to cathode of the 805?
I bought them directly from China
. They are the regular MC3008-A, not A2. I don't the differences between A and A2.
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88Man,
You can buy direct from the factory, afew weeks ago Ms.Suena had a special price for the 211 amp with this same chassis.
Although they dont accept Paypal, just bank account deposit.
LEGIS:
I cant wait for your impressions after these mods.
Good luck.
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Well, do you would inform me what are the differences between A and A2?I bought them directly from China
Thanks
I don't think there is (was) much difference except the claimed DC heated AX7/AU7 in A2 whereas regular A has AC?
I made a switch for the GNFB:
An externally hosted image should be here but it was not working when we last tested it.
I also tried the cathode feedback (CFB) around the output tube (existing cathode resistors connected to 8ohm tap instead of ground), it resulted around in 2-3dB of local feedback. It's good when the GNFB is disabled, but not good when GNFB is enabled since it reduces the GNFB. I will put CFB also behind a switch so it can be only used when the GNFB is disabled.
I think I will change the AX7 tube to to another AU7 to reduce gain around 10,5dB (which is massive when ~12-13dB GNFB is disabled, changing to AU7 almost compensates for it). Already tested it and AU works and measures good in AX's place.
I changed some basic diodes to Hexfred ultra fast/soft recovery ones. Maybe the diode bridges would also be a good spot for soft recovery diode bridges...
Point to point wiring is so good when it comes to DIYer who wants to try out different things and do some component mods. Ming Da also does it SO neatly.
The MingDa solder guy is a marvelous artisan.
Hard and important work, a great artist.
)He should earn a great salary.
https://www.youtube.com/watch?v=zND2SAjzyPc
The sound is magnificent - and very SET-tubey of course. They sound very strong, with my horns they are the most dynamic of all the amps I have heard in my system including every, even very powerful transistor amp. The "nuance clarity" and harmonical richness/reality is superb imo. You can hear the tonal palette/"the tone"/harmonic content of different instruments (let them be acoustical like human voice or cello, or electrical like electric quitar) very clear and you feel strongly that they sound like they should. With the correct dynamics and harmonic richness the music becomes involving and touching. They also have very nice, deep and taunt bass for a SET amp, even without the GNFB. I bet it has lots to do with the big output transformers and perhaps the 805 tube.
Thanks for your impressions and congratulation on your purchase.
This is a similar report of other custumers I have read in the past.
Do you will put softstart and two power switches in these amps?
This would extend the 300B/805 tubes life.
I have no idea. I planned to make a switch that allows using 845 and 211 tubes in MC3008-A.
I will also make external PSUs for both monos, where all the AC->DC conversion is made. The PSU's will have chokes (5 chokes per ch), polyprylene caps, fast switching diodes. I will also make DC heating for the AX/AU7.
I have also potted the OPT's with epoxy and I like it. Better clarity.