DIY cheap microphone preamp for Canon DSLR #2 soldering components into PCB
15Part #2 of a step-by step tutorial on how to build a cheap microphone preamplifier for Canon DSLR cameras. The audio is awful, because I did not had the amp yet to help with the audio,
so now you can hear how much noise the DSLR preamp is introducing. Compare this to the beginning of the first portion of video #1 in this series, or the last 5 minutes of video #3, and you can hear that the difference with the preamp is heaven and earth.
The preamp very much improves the audio quality, reduces the hissing noise and also flattens the piercing S sound in your videos. I have noticed that it also totally removes the clunking noise you hear in the video when the record button is pushed. With the aforementioned issues even post-production can not help much in software, and I am very happy that the preamp takes care of these issues.
The build is rather simple, so it can be easily put together by hobbyists. Total costs around 20-25 Euros including the battery.
Component lists:
------------------------------
Microphone: clip-on lapel microphone of an old Samsung mobile phone headset
The headsets from old mobile phones are good and inexpensive options.
You just need 2 minutes to figure out which leads are going to the microphone with a multimeter.
Conrad microphone preamplifier kit: 11.99 Euro
http://www.conrad.com/ce/en/product/197688/Conrad-mono-microphone-preamplifier-kit
Plastic case: 2.69 Euro
http://www.conrad.com/ce/en/product/522066/Module-casing-64-x-53-x-28-Polyamide-Black-AMG-2-1-pcs
Schielded audio extension cable, optional: 2.5 meters, 6.99Euro
http://www.conrad.com/ce/en/product/325051/Jack-Audiophono-Extension-cable-1x-Jack-plug-35-mm-1x-Jack-socket-35-mm-250-m-Black-SpeaKa-Professional
3.5 mm audio jack Socket with fixing screw: 2.09 Euro
http://www.conrad.com/ce/en/product/738619/35-mm-audio-jack-Socket-vertical-vertical-Number-of-pins-3-Stereo-Black-Lumberg-KLB-4-1-pcs
3.5 mm audio jack Plug: 1.99Euro
http://www.conrad.com/ce/en/product/738920/35-mm-audio-jack-Plug-straight-Number-of-pins-3-Stereo-Black-Lumberg-KLS-40-1-pcs
9V battery: 2.5-4 Euros, depending on location/manufacturer
9V battery leads: 0.35Euros:
http://www.conrad.com/ce/en/product/490660/T-Style-9V-Snap-Clip-With-150mm-Wire-Leads
Power On/Off switch with a slider switch: 0.79Euro:
http://www.conrad.com/ce/en/product/708046/Slide-switch-50-Vdc-02-A-1-x-OnOn-SS-12-05-1-pcs
Optional for power indication:
LED for indicating PowerON, and a series resitor for the LED.
However, it will deplete the battery faster. Instead, I use Magic Lantern, where I can visually see when the preamp is turned on from the audio bars at the top of the screen during recording.
Audio setting in Magic Lantern for my Canon T3i, aka Rebel 600D:
------------------------------------------------------------
Override audio settings: ON
Analog gain : 0dB
Mic Bosst: 0dB
Digital Gain -- go inside the submenu
Record Effect Mode: Notch filter
Record digital volume: 0
Left digital gain: 0dB
Right digital gain: 0dB
AGC: OFF
Input source: External stereo !do not forget to select this!