Ever wondered what those weird looking speakers are on the kick drum?
I was intrigued by how and why these simple devices were being utilised in state of the art studios.
First of all you if you take any speaker and wire it backwards it essentially becomes a microphone. Sound pressure moves the speaker cone (diaphragm in a mic) and sends a voltage down the line.
But why would you use this for a microphone? surely it's not high quality.
The reason engineers all over the world use the Yamaha NS10 speaker (in reverse) is not because it's a high quality microphone but because of it's slow frequency response and very little damping.
Because of the Yamaha NS10's makeup (naturally free moving) it produces a movement which generates the desirable low end sound.
Here is a quick guide on how to make it.
STEP 1 - Equipment needed.
- 1 x Yamaha NS10. (E bay from Japan)
- 1 x microphone clip.
- 1 x XLR cable.
- Soldering Iron.
- Wire strippers ( or use the razor blade)
- Cables ties (optional)
Note: If you don't want to do this you can try and just use the magnet on the speaker and stick to a microphone stand. I found that it tends to slide around and not be very stable.
STEP 2 - Assembly
- Cable tie microphone clip to one of the speakers metal holes on the outside.
- Cut XLR in half or to acquired length, the FEMALE SIDE will be getting used only.
- Strip back some insulation and mesh to find the 2 wires red and white, then strip the end off those 2 wires.
- No solder is actually needed due to speaker already having enough on the back, just heat up, stick wires in and cool down in position.
- RED WIRE GOES TO RED, WHITE WIRE GOES TO WHITE
- Cable tie XLR to make neat and your ready to go.
Important: DON'T use phantom power! I've used this on a few different console and each time no pre amp gain has been needed so leave the pot down or trimmed down. People have been known to buy or make a -20db pad for more level control but I haven't seen the need for one yet.
The 2 audio clips below were recorded the same time. I was hitting a cushioned seat which didn't have much low end to begin.
I realise these 2 clips are probably not the best to compare each other in turns on bass mics. But if you notice how much bass is picked up from a generally high frequency noise, it's quite a lot.
References:
Sound On Sound. (2014, November). Can I make a "Subkick" from any speaker cone. Retrieved from http://www.soundonsound.com/sos/nov14/articles/qanda-1114-04.htm