Mavis Prima MPA-81s is a very nice donor mic platform

[Wordsushi]

The Mavis Prima MPA-81s is a brand new mic from the people at BaiFei Li. They asked if I wanted to review it, and though I wasn't really interested in it on its own, I thought I saw potential as a donor mic, especially as a platform for the stunning Arienne Flat K47.

It's very much a copy of the Vanguard V4, even with a very similar kit including a mic suitcase and bamboo wooden mic box and shockmount. As you can see by the internals, the circuit board is identical to that of the Vanguard. It comes stock with a k87 style capsule.

I've made a few videos with it. Here it is unmodded.
Here it is side by side with the V4
Here it is with a cheap C12 style capsule swapped in
And finally,
With the Arienne Flat K47

The Vanguard V4 currently sells for $699 and the MPA-81s is on Alibaba for about $250 shipped. Overall, the build is solid. The kit is very nice and it's a mic worth more than the sale price, and I think as a donor platform, it's a compelling option because the circuit is decent and fairly quiet. As this came up as a topic on the ORS87 thread, I thought I'd make another thread for it just in case any one was interested. True, there are certainly many transformerless donor mics out there, but this one being multi-pattern and having such a nice kit, I thought it deserved a look-see.

 

[Wordsushi]

Yes, I should try it of course when I think about it. And then maybe buy another flat K47 later if I wanna keep it that way but build U47 style microphone.

It was almost 30 years ago I held a solder iron way back when lead was used and multi-bit PCM DAC was a thing (Burr-Brown PCM1704).
This DIY microphone thread sparkled my interest to build something again. Thanks for that. My older Weller seems to work still so it will be exciting.

A capsule swap is the easiest mod here, but it has a complication that I will explain.

In the top photo, you can see there are two pads on the upper left of the board. That is where the front and back capsule leads attach to the board. That's easy.

But if you are wanting to swap in the Arienne Flat K47, you will need to also swap out the entire capsule mount. The stock mount is too small and the holes don't line up to accomodate the Flat K47.

The capsule deck has drill holes to accommodate a number of different mount pedestals, including the kind with 4 screws at the corners that can easily be 3d printed.

Also, to access the screws attaching the headbasket you will have to unscrew the two boards from the PCB rails since the switches on both sides are centered exactly under those two screws.

 

[Wordsushi]

Lastly,
Though the circuit is identical to the V4, with the stock capsule it doesn't sound exactly like the V4, and even with a capsule swap to a cheap c12 style, the V4 sounded better, so I think Vanguard is using a better than average stock capsule. But with the Flat K47, I think this mic stands tall against the V4 at what all total would cost you around half as much as a new V4.

 

[AdamFrisen]

Lastly,
Though the circuit is identical to the V4, with the stock capsule it doesn't sound exactly like the V4, and even with a capsule swap to a cheap c12 style, the V4 sounded better, so I think Vanguard is using a better than average stock capsule. But with the Flat K47, I think this mic stands tall against the V4 at what all total would cost you around half as much as a new V4.

Thanks for the details.

I saw your other video where you replaced with flat K47 for BFL V47 and I ordered this saddle. Would it also fit inside?

https://www.aliexpress.com/item/100...UwAR7zyA&utparam-url=scene:search|query_from:

 

[gyraf]

It's very much a copy of the Vanguard V4

Is there any reason to believe that it actually isn't a Vanguard V4?

The Vanguard is more or less a Peluso operation iiuc - and someone will have to manufacture it, why not Mavis?

/Jakob E.

 

[McIrish]

On the one hand, I'm glad there is a pretty nice donor body available. On the other hand, I'm sad that the Vanguard design is not protected in any way. Those shops in China don't have any regard for any intelectual properties. Zero ethics. It pisses me off. I own a couple Vanguard mics and use the V44S Mk2 all the time on drum room.

 

[Wordsushi]

Thanks for the details.

I saw your other video where you replaced with flat K47 for BFL V47 and I ordered this saddle. Would it also fit inside?

https://www.aliexpress.com/item/1005002506372039.html?spm=a2g0o.productlist.main.1.6b78jiTwjiTwnf&algo_pvid=035d6e9c-36f1-4bf0-92db-8975f6a889f5&algo_exp_id=035d6e9c-36f1-4bf0-92db-8975f6a889f5-0&pdp_npi=4@dis!SEK!34.40!34.40!!!3.21!3.21!@210387dd17188718433151742e42b7!12000020922629797!sea!SE!4246410657!&curPageLogUid=FPh2UwAR7zyA&utparam-url=scene:search|query_from:

Yes, that should work fine. The Mavis has a center hole in the capsule deck. You will probably need an m2.5 or m3 screw for it.

 

[Wordsushi]

Is there any reason to believe that it actually isn't a Vanguard V4?

The Vanguard is more or less a Peluso operation iiuc - and someone will have to manufacture it, why not Mavis?

/Jakob E.

That's a really good question. I had no idea Vanguard was part of the Peluso crime family.
Mavis Prima is a BaiFei Li sub-brand and a cardioid version of this circuit is used in their V47 mic. I'm fairly certain they do not make their own mics, but do assemble their own mics. They claim to be a big player in China so it's quite possible they are somehow professionally aligned with whomever is making the Vanguard. It's definitely the same exact circuit with different printing, stuffed into a slightly different body, with a k67 atop. It's not the V4, but it's close enough to question the paternity.

 

[Wordsushi]

On the one hand, I'm glad there is a pretty nice donor body available. On the other hand, I'm sad that the Vanguard design is not protected in any way. Those shops in China don't have any regard for any intelectual properties. Zero ethics. It pisses me off. I own a couple Vanguard mics and use the V44S Mk2 all the time on drum room.

Don't be sad. I get where you're coming from, but to play Devil's Advocate, what exactly is Vanguard doing with the V4 that is unique enough to warrant protection? Paint it purple? Give you a suitcase? It's not like they have a patentable product, just a nicer copy of countless mics that came before it.

 

[gyraf]

Yeah, I'm not thinking they're related to Peluso per se, rather that it's the same type of business..

 

[Voyager10]

Looks like a fairly standard Schoeps-type transformerless circuit, not exactly groundbreaking.

There are some components (Q5 and a 150M resistor etc) near the top of the back PCB - any ideas? If that's a pad switch, perhaps it drops the capsule voltage?

 

[Khron]

There are some components (Q5 and a 150M resistor etc) near the top of the back PCB - any ideas?

One CAN just about make out a "-10d" near the top of that rear PCB...