so i have this weird problem, i just bought cheapo generic BM-800 microphone

i plug it directly to my PC, while i generate some noise, but overall its ok, as to be expected

then i try to boost the mic using my phantom power, and it generate much worse noise

thats weird i tho, so i buy new usb soundcard, and i try to put it back directly and its better, almost no noise at all

but then i try to plug it in again with phantom power, no matter if its turn on or turn off, the noise come back and its just as worse, anyone know why this happen, and what is the ideal fix?, thanks

Equipment list :

Phantom Power : http://krezt.co.id/product/krezt-ph-710kzt/

Mic : https://www.amazon.com/Excelvan-BM-800-Microphone-Broadcasting-Voice-Over/dp/B00KMKIR9Y

USB adaptor : https://www.amazon.com/UGREEN-External-Headphone-Microphone-Desktops/dp/B016CU2PEU

heres the noise example :

edit : the problem as far as i'm aware is not on the microphone itself, the microphone actually works great, but its on the phantom power, for some reason, either turn it off or on, as long as its plugged to the well, it will generate that noise

note : after consulting to lot of people from different forum, i can safely conclude it might be the phantom power defective, the main indicator is from my original edit with "as long as its plugged to the well, it will generate that noise", the power supply circuitry from the phantom power might be broken

  • Sounds like leak-through from the computer itself; but we need more info as to precisely what sound equipment is in use, how it's wired, what the phantom power unit is, etc...
    – Tetsujin
    Dec 22 '17 at 13:01
  • thanks for the reply @Tetsujin , heres the complete list Phantom Power : krezt.co.id/product/krezt-ph-710kzt Mic : amazon.com/Excelvan-BM-800-Microphone-Broadcasting-Voice-Over/… USB adaptor : amazon.com/UGREEN-External-Headphone-Microphone-Desktops/dp/… Dec 22 '17 at 13:06
  • yeah... all pretty iffy stuff - I found a couple of duplicates of this type of setup here, which I think cover it already - sound.stackexchange.com/questions/40862/… & sound.stackexchange.com/questions/37504/…
    – Tetsujin
    Dec 22 '17 at 13:16
  • but the problem is not on the microphone itself, the microphone actually works great, but its on the phantom power, for some reason, either turn it off or on, as long as its plugged to the well, it will generate that noise Dec 22 '17 at 13:22
  • best guess is mismatched impedances. It's all a bit 'headset' rather than pro levels. It's not stuff I've ever used, so don't know how it's meant to behave, but high-z tends to lower volume levels & raise noise, so that's what you're getting. One of these days I'm going to have to throw 25 bucks away on one of those mics, just to see what they're actually like. They're cheaper than a decent mic cable, & there's just the outside chance the cradle would fit my U87 which is missing one ;)
    – Tetsujin
    Dec 22 '17 at 13:33

If you get better results without that phantom power adapter, don't use that phantom power adapter. The microphone apparently does not need phantom power for condenser polarization but just for powering its FET preamp. 5V will be fine, and that's what the external mic adapter with 3.5mm input will provide.

The microphone provides a mishmash of several technologies and interface methods. Use that which works best for you. The phantom power adapter may be low quality, or it may make worse assumptions about what the computer side wants to see or what the microphone side provides than suitable for its intended operation.

It would be moderately interesting to see how this microphone behaves when connected with a true XLR cable to a true balanced low-impedance microphone input like on a high quality mixer or high-quality audio interface. However, buying something like that in the hope to get better results will likely be a waste of money.

  • I'll let you know in a couple of weeks when my BM-800 arrives from China. I don't know how they even make money on these things, shipped for £8 ;) First test, plug it up like a proper condenser mic. 2nd test, plug it up like a headset. Compare. I'll let you know if I will be selling my U87 & getting 350 of these instead ;)
    – Tetsujin
    Dec 22 '17 at 13:55
  • the problem is its not the mic fault, i already try to use my other sennheiser dynamic mic, the reason i'm not use it is because its quite old and sometimes generate pop from god knows where, its still generate the noise, its purely phantom power fault in this case Dec 22 '17 at 14:21
  • i think the phantom power is defective, still contacting the seller if its possible to get a refund or at least change the product Dec 22 '17 at 14:23
  • I don't think it's necessarily defective, just not a match for the mic. It's a consumer unit, 600ohm.
    – Tetsujin
    Dec 22 '17 at 14:24
  • please read my additional note on the original post, its still generate noise even WITHOUT any mic attached, just the phantom power, doesnt matter if its turn on or turn off, as long as its plugged into the wall, its generate noise Dec 22 '17 at 14:27

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