CLOSED CLOSED CLOSED
Withdrawn from sale, at least for now. May try to do something with these.
Selling “as is”, two Ming Da MC300A-R monoblock amps for $300 + shipping. Things weigh a ton, so shipping would not be cheap. My wag is $100 for shipping. US domestic shipping only.
Would prefer local pick up in LA, will give preference to a local buyer. Can meet you somewhere during the week, within reason. I work in El Segundo, by LAX.
If I get a have to ship offer first, I’ll wait 24 hours to see if I get a pickup offer. If no offer in 24 hours, then I will ship. I do have the boxes they were shipped to me in, found them in my garage rafters last night.
Bought these as “projects” about 9 years ago. Tried to fix them, couldn’t, and they have been sitting on my shelf for too long. I was NEVER able to get them working.
I think the design is flawed, which is why they were sold in the first place. Also probably why you find very little information on them in a google search. So my mistake I think was trying to get it working without changing the design. I had one powered up at some point, and then I remember a wire smoking. That’s when I gave up on em.
To make these work, you probably need to rip out all the parts, and just use the transformers and tube sockets, and implement a known design.
The chassis is designed for two 6SN7 and one 300B. So you have two octal and one DHT socket to work with.
2.5 k output transformers with 8 and 4 ohm taps.
Solid state (diode) rectification, and CRC for generating B+. Design had AC heating for octals and unregulated DC for DHT.
I have the schematic, and will supply it to the buyer, FWIW.
The two amps have different parts in them, the person I bought them from was modding one of them before giving up and selling to me.
So to sum it up, for $300 + shipping you get two monoblock chassis, and two power and two output trannys, sockets, hardware installed and whatever parts are in them. But I’m not even sure the trannys work. I do have the bottoms which have cheap feet on them, but probably lost the screws for the bottoms, so figure no screws and you need to replace. Also no screws holding in one of the power switches, I taped it in place. One of the tranny covers had a nick in the corner, you can see it in the pics.
No guarantees, since I never made them work, buying strictly as is.
I put a bunch of pics here. What you see in the pics is what you get, + the bottom plates. Nothing else. No tubes, screws, etc.
link to pics
If I ship, figure it will take me a week to box up and ship, so don’t be in a hurry to get them.
Randy
Withdrawn from sale, at least for now. May try to do something with these.
Selling “as is”, two Ming Da MC300A-R monoblock amps for $300 + shipping. Things weigh a ton, so shipping would not be cheap. My wag is $100 for shipping. US domestic shipping only.
Would prefer local pick up in LA, will give preference to a local buyer. Can meet you somewhere during the week, within reason. I work in El Segundo, by LAX.
If I get a have to ship offer first, I’ll wait 24 hours to see if I get a pickup offer. If no offer in 24 hours, then I will ship. I do have the boxes they were shipped to me in, found them in my garage rafters last night.
Bought these as “projects” about 9 years ago. Tried to fix them, couldn’t, and they have been sitting on my shelf for too long. I was NEVER able to get them working.
I think the design is flawed, which is why they were sold in the first place. Also probably why you find very little information on them in a google search. So my mistake I think was trying to get it working without changing the design. I had one powered up at some point, and then I remember a wire smoking. That’s when I gave up on em.
To make these work, you probably need to rip out all the parts, and just use the transformers and tube sockets, and implement a known design.
The chassis is designed for two 6SN7 and one 300B. So you have two octal and one DHT socket to work with.
2.5 k output transformers with 8 and 4 ohm taps.
Solid state (diode) rectification, and CRC for generating B+. Design had AC heating for octals and unregulated DC for DHT.
I have the schematic, and will supply it to the buyer, FWIW.
The two amps have different parts in them, the person I bought them from was modding one of them before giving up and selling to me.
So to sum it up, for $300 + shipping you get two monoblock chassis, and two power and two output trannys, sockets, hardware installed and whatever parts are in them. But I’m not even sure the trannys work. I do have the bottoms which have cheap feet on them, but probably lost the screws for the bottoms, so figure no screws and you need to replace. Also no screws holding in one of the power switches, I taped it in place. One of the tranny covers had a nick in the corner, you can see it in the pics.
No guarantees, since I never made them work, buying strictly as is.
I put a bunch of pics here. What you see in the pics is what you get, + the bottom plates. Nothing else. No tubes, screws, etc.
link to pics
If I ship, figure it will take me a week to box up and ship, so don’t be in a hurry to get them.
Randy
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They are covers, not potted.
I think they are ok, but since I've never had them work I can't say for sure.
I found the bolts that hold the covers in place this morning, you can see them in the pics if you look carefully.
Randy
Some more information.
I undid the 8 nuts holding the transformers in place, 4 nuts per tranny.
The cover and tranny are bolted together, so they want to come off the amp together. Since the tranny's are wired to the amp, I couldn't pull them off without unsoldering the wires.
I was able to lift them a inch or so, and see under the cover. Saw the tranny, and some of the hardware holding it in place. If you unsoldered the wires, then you could take them off.
inner dimension of each chassis is about 17 x 7 3/4 x 2 inches. The 7 3/4 width is side to side, but there is a lip which kind of gets in the way,but you can go under the lip.
The tranny boxes are about 4.75 inch cubes.
Enough room inside to do a lot.
Also, while I can't say for sure the tranny's work, I have no reason to believe they don't.
I may have powered it up before with no speaker or load attached, wondering if that's why I smoked a wire?
Randy
I undid the 8 nuts holding the transformers in place, 4 nuts per tranny.
The cover and tranny are bolted together, so they want to come off the amp together. Since the tranny's are wired to the amp, I couldn't pull them off without unsoldering the wires.
I was able to lift them a inch or so, and see under the cover. Saw the tranny, and some of the hardware holding it in place. If you unsoldered the wires, then you could take them off.
inner dimension of each chassis is about 17 x 7 3/4 x 2 inches. The 7 3/4 width is side to side, but there is a lip which kind of gets in the way,but you can go under the lip.
The tranny boxes are about 4.75 inch cubes.
Enough room inside to do a lot.
Also, while I can't say for sure the tranny's work, I have no reason to believe they don't.
I may have powered it up before with no speaker or load attached, wondering if that's why I smoked a wire?
Randy
Still for sale, just sitting in my garage right now.
Sorry for delayed response, I didn't see this post before.
I did have a PM yesterday, but just an inquiry so far.
Randy
Believe whatever you want.
And although I sometimes think things about for sale threads, I hold back from thread crapping on someone's sale.
IMHO, shipping is killing this, which is why I really wanted to make a local sale on these, but no local interest.
It's just I've been too busy with other stuff and lazy to test/troubleshoot these amps.
And although I sometimes think things about for sale threads, I hold back from thread crapping on someone's sale.
IMHO, shipping is killing this, which is why I really wanted to make a local sale on these, but no local interest.
It's just I've been too busy with other stuff and lazy to test/troubleshoot these amps.
I also think same thing. Post pics of wiring and parts please.
Possible fried before it work and no just dump?
Cheap china transformers not sure if work,
if not working etc = sheet metal price.
Maybe Hammond transformer you sold was for this project?
Hope if honorable person list here,
also, not find many pictures as stated.
thank you for time
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NEVER able to get them working... you kept the tubes for a new project?
Just curious, because it looks like a simple design and easy to repair any problems, there is not even a pcb!.
Did the amps play some music? what caused it not to sound anymore in both. This is the information someone wanting to fix it would like to know.
Just curious, because it looks like a simple design and easy to repair any problems, there is not even a pcb!.
Did the amps play some music? what caused it not to sound anymore in both. This is the information someone wanting to fix it would like to know.
Hey all, enough negativity. There are no claims being made. If I lived locally, I would take them as is for $300. Odds of all the transformers being out is small, the risk is small and there are some good articles about these amps being quite good with some small circuit mods.
This is a nice deal for someone local. If shipping to Denver was cheap, I might still buy them.
This is a nice deal for someone local. If shipping to Denver was cheap, I might still buy them.
Hi folks,
I have several Ming Da amps. Ming Da transformers are excellent. I don't know if any of the transformers are bad but I think that this is a good opportunity to build a 300B amp with your own circuit.
I pm'd Randy about buying them and will do so after next months paycheck if they are still available.
Steve
I have several Ming Da amps. Ming Da transformers are excellent. I don't know if any of the transformers are bad but I think that this is a good opportunity to build a 300B amp with your own circuit.
I pm'd Randy about buying them and will do so after next months paycheck if they are still available.
Steve
Don't mean to troll, but why didn't you just check the tranny primary and secondary for at least continuity and remove some doubt? Too much work, or just feel the need to be uncertain to make the sale?
Plausible Deniability: The act of someone who actively avoids gaining certain knowledge of facts because it benefits that person not to know.
Its 2 minutes of confirmation. It would have served you just as well as everyone else that may have been interested...correct?
Plausible Deniability: The act of someone who actively avoids gaining certain knowledge of facts because it benefits that person not to know.
Its 2 minutes of confirmation. It would have served you just as well as everyone else that may have been interested...correct?
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