Those ridiculously cheap microphones!

Those ridiculously cheap microphones!

Postby Ted Fletcher » Tue Oct 28, 2014 11:32 am

I'm sure that everyone in the pro-audio business has noticed the sudden plethora of ridiculously cheap 'professional' capacitor microphones.....
Last week I spotted one at 15 quid; that includes VAT and postage! While my microphone collection is extensive, I couldn't resist the temptation so I bought one and spent a whole day testing it really carefully against the yardstick of my own design 'JM47' and 'TB47' as well as a handful of AKG, Shure etc.
Have you guessed it?? The results are far from 'rubbish'.
These BM-700 and BM-800 mics are well made in the Neumann style but with electronics optimised to work with anything that requires a simple cheap 'tie-clip' type of electret mic.
The actual capsule is a TSB 160A made by Transound. This is a cardioid response capsule with no electronics fitted. The FET pre-amp is mounted on a separate PC board in the mic body.
Performance? It's very good indeed. The response and the actual 'sound' of the mic has that expensive sheen; it is extremely 'flat' from below 20Hz up to 12K where it wriggles a bit. There is the characteristic small 'kick' at about 3.5KHz, common to many electrets where some phase effects cause amplitude distortion and give it a very slightly 'bright' sound, but on balance, I would be more than happy to use it on a vocal session. It's a worthy mic at any price.
Noise? It's actually just as good as most traditional capacitor mics and much better than any of my test electrets.
If I was starting a studio right now, I would want a good handful of these mics......
The only problem is that they come with a silly 3.5mm jack plug connection and I must admit that I cut that off straight away and designed a simple little circuit that would provide 12V DC supply from the standard mic-amp 48V phantom.
(If anyone would like details of that, please email me on ted@tfpro.com) :)
Ted Fletcher
 
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Re: Those ridiculously cheap microphones!

Postby Griff » Sat Feb 14, 2015 3:03 pm

I have seen these Ted! In fact, every time I go onto by eBay bookmark, one of these is at the top of the list. At just over £22 and looking miniature. I wouldn't have given them a second thought. I'm half tempted to give one a go now just for a bit of fun. Perhaps good for miking up a guitar cab?
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Re: Those ridiculously cheap microphones!

Postby Griff » Wed Feb 18, 2015 4:00 pm

There seem to be quite a few variations. The "square" edged model I think you found, seems to be the latest. Earlier models include one running on batteries and one requiring phantom power.

This one appear to have a "proper" capsule. I suspect this is the model we're seeing on eBay as BM-700 (even though this video says BM-800)

https://www.youtube.com/watch?v=EqR0os3r_2Q

I guess there's only one way I'm going to find out :)
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Re: Those ridiculously cheap microphones!

Postby Ted Fletcher » Fri Sep 04, 2015 11:04 am

Some new input about these microphones...... some may not be up to much!
I have 2 types; the BM800 (with the squarish top grille) has a fairly complicated PC board in the body with 20 components on it.
It works well directly connected to the computer via the conventional 3.5mm mic jack socket, and I am using it with a small conversion circuit so that I can run it off the 48V phantom power of a professional mic input. It performs extremely well.
HOWEVER... I also have a similar mic but with a sloping grille....marked 'VASEN BM800' and this one is a con! It is simply a cheap electret capsule directly wired to the XLR socket on the mic base. On test I noted that it did not sound quite so good, and it was noisy. A couple of days ago it failed and became very noisy. Getting it apart was a challenge as the screw base was filled with paint. I admit to destroying it completely .... but it was broken anyway!
So it's just a word of warning.... those Chinese mics are NOT all the same!
I shall buy another one just to check.... and I will report on it here. :)
Ted Fletcher
 
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Re: Those ridiculously cheap microphones!

Postby Ted Fletcher » Mon Oct 19, 2015 7:03 pm

And for some more news on these mics.....
I bought yet another one; and it cost me £10.95! This one again is marked BM-800. I took it to pieces (of course) and spent a happy hour tracing the circuit. It's clever and not at all 'cut price'. It contains a respectable FET head amplifier and some circuitry to work correctly from a conventional 48V phantom system via a regulator and impedance converting transistors. So I have done some more scientific testing and compared it to one of my own old JM47 mics..... The 'ten quid' mic is very good, and in terms of 'quality' it has the 'big condenser' sound but the noise level is a couple of dB higher than my old faithful. It does have that indefinable character that electret mics possess; it's a slightly 'cooler' sound than the old fashioned expensive mics that cost about 50 times as much.
So once again I would recommend the cheepo mic, particularly as the current models work perfectly well direct with a phantom powered mic pre. :)
Ted Fletcher
 
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Re: Those ridiculously cheap microphones!

Postby guntherbuff » Thu Mar 08, 2018 9:00 pm

Are you finding these on Ali express? May get a pair myself! For around a tenner each you can't really go wrong! I wonder how they would sound as a pair of drum overheads...
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Re: Those ridiculously cheap microphones!

Postby Ted Fletcher » Wed Mar 21, 2018 7:35 pm

For some inexplicable reason I did not see the last post on this thread until now.....
The answer is yes, it's pot luck if you get the good ones, but frankly at that price (and this is still the case) what have you got to lose?
The mics I have which operate from 48V phantom are definitely good for drum overheads... good pattern, wide response and good sound. :)
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