Microphone Mixer

Home > Circuits > Sound/Radio > Microphone Mixer
Author Views Views Today Rank Comments
Anatoly I. Shikhatov 243,957 5 26
This relatively simple mixer was designed for three dynamic microphones, but can be re-designed for more or less. Level and tone controls are available to tailor the sound to your needs.


Schematic for mixer


Total Qty.
R1, R2, R331K 1/4W Resistor
R4, R5, R6310K Logarithmic Pot
R711Meg 1/4W Resistor
R8, R10210K 1/4W Resistor
R9, R112100K Linear Pot
C1, C2, C5, C640.1uF Ceramic Disc Capacitor
C3, C4222nF Ceramic Disc Capacitor
U1, U22741 Op Amp
J1, J2, J33Input Jacks Of Your Choice
MISC1Board, Wire, Knobs, IC Sockets


  1. Email Anatoly I. Shikhatov with questions, comments, etc.
  2. R1-R3 are level controls. R9 and R11 control bass and treble, respectively.
  3. Since the circuit draws such low current, two 9V batteries can be used for a power supply.
  4. Building the mixer in a metal case will cut down on noise.

Related Circuits

3 Watt FM Transmitter, 8 Watt Audio Amp, 22 Watt Audio Amplifier, 50 Watt Amplifier, Crystal Radio, FM Transmitter, Guitar Fuzz Effect, FET Audio Mixer, Microphone Mixer, 8 Note Tune Player, Op Amp Radio, Mono To Stereo Synthesizer, Electronic Stethoscope, Tone Control, Transistor Organ, Stereo Tube Amplifier, Digital Volume Control, Sound Level Meter, Aircraft Radio Communications Receiver, Single Chip FM Radio, One Tube Regenerative Radio, Single Chip AM Radio


Add A Comment

Microphone Mixer
Friday, March 11, 2016 8:55:10 AM
Hi Experts. For a personal monitor/mix. Could this be used to feed a headphone amp with the inputs J1-3 passing through (as before) to the main mixer ?? OR where would this fail ? Thanks, Jon
Microphone Mixer
Thursday, December 27, 2012 9:46:37 AM
Anyone know the noise floor could below 2uV(-115dBV) A-weighting?
Microphone Mixer
Tuesday, September 04, 2012 6:32:54 PM
Thanks, I build this circuit and it work fine.
Microphone Mixer
Saturday, May 28, 2011 1:10:04 PM
1.For questioner on Friday, February 12, 2010, look at schematic, that clearly shows + and minus 9v. 2.For shoaib, follow the instruction, IE use 2 9v batt, eliminating MAX error, Feed in 1Khz signal (or music) at uV to 1 volt and lisen or look with oscope at U1 pin6, R8 and then u2 pin 6 to check for signal stopage. Generate signal with pot or volt divider from strong source. 3.Bill, look harder, it is also 0.022 uF or microfarad. Do not substitute much, IE 20 uF or 24uF as it will likeley not work well. 4.For Sunday, January 06, 2008 question, you can not use 386 but you can use TL071 which will work down to less than 8 volts. Put 2 10k resistors (in series) accross batt and make the center of them the ground of the circuit (making 2 4.5v "supplies). It will not have much head room. 5. balu, as above, you can use TL071 and use the Batt supply to test if the hum is from your power supply. Enclose it is metal case, make all wiring close, use a shielded cable to the mic. Increase size of C1,2,5,6, add a 5 or 10uF to each batt to ground(watch polarity, + to +).
Microphone Mixer
Monday, April 19, 2010 10:08:37 PM
this circuit is nice, but do TL0712 works like the 741 OP AMP? what are the characteristics of TL072?
Microphone Mixer
Friday, February 12, 2010 1:41:24 PM
When you say 2 9v batteries, do you mean in series or in parallel? Does that mean the circuit needs 18'v?
Microphone Mixer
Tuesday, August 25, 2009 4:30:40 AM
ok this is nice and these are helpng me to know aboutr electroncs so a heartiest thanks to u.
Microphone Mixer
Monday, January 26, 2009 2:33:17 AM
i complete circuit & cheak out many time but my circuit not work i use the max1044 ic for 9v+ 9v- supply what i do help any one plz
Microphone Mixer
Sunday, May 25, 2008 9:52:34 AM
usE TL072 op instead of 741
Microphone Mixer
Friday, April 11, 2008 10:26:33 PM
I can't find the two 22nf capacitors. can I substitute them with another value?
Microphone Mixer
Wednesday, January 16, 2008 8:37:23 AM
nice guys. keep the good work on. I need more of audio electronics circuit
Microphone Mixer
Sunday, January 06, 2008 10:22:38 PM
Can ur circuit supply 9V power. becoz i only need to use 1 capsule microphone and can i use other kind op amp like LM386
Microphone Mixer
Friday, January 04, 2008 7:55:22 AM
I tried above ckt, but getting hum. How to reduce hum? can i use other better OPAMP instead of 741.
Microphone Mixer
Tuesday, December 18, 2007 3:58:46 AM
this is very good
Microphone Mixer
Monday, November 19, 2007 10:09:58 AM
i want the one with four input (jake)
Microphone Mixer
Friday, October 26, 2007 9:43:59 AM
can i get an explanation about jacks? can it be replaced with something else? i need the explanation & working of this circuit
Microphone Mixer
Friday, August 10, 2007 5:13:55 AM
Can i connect output of mixer in input of preamp ( Tone Control ) ( the circuit i found on this page ) and after preamp in 22W amp ( the circuit i found on this page ) ? and can i do this mixer without preamp because i have preamp ( Tone Control )? Is necesary to do in 9 V? Can i put 12 or 15V?
Microphone Mixer
Monday, July 09, 2007 1:59:33 PM
can the variable resistance also controlled by a microcontroller?
Microphone Mixer
Friday, May 25, 2007 5:13:56 PM
I ma an eletornicman Iwhet you to have a chat willf you on mixer circuit m
Microphone Mixer
Monday, May 07, 2007 5:05:51 AM
This circuit appears to be exactly what I'm after. Is the signal out sufficient to be treated as line out or will it require further gain from a microphone pre-amp?
Microphone Mixer
Saturday, May 05, 2007 2:29:18 AM
dear guys! does it amplifies in addition to mixing? and is it possible 741 op amp? thanks for your dedicated help
jibran ahmed siddiqui
Microphone Mixer
Saturday, April 28, 2007 2:40:13 PM
i want some suggestions about my final year project,i am a student of telecom engineering and this is my final year, i am very worried and having difficulty to decide my project.please reply me on my email address as soon as possible. thank you
mohammad barakat
Microphone Mixer
Thursday, April 26, 2007 2:57:02 AM
i want the discription of this circuit
mohammed jamal
Microphone Mixer
Saturday, April 21, 2007 2:57:36 PM
i want the discription of this circuit
Microphone Mixer
Friday, March 30, 2007 7:39:03 PM
i do hav a 60Watts power audio amplifier,but it has no microphone input.....can i used this microphone mixer of yours? and how will i connect this to my power amplifier? please respond me A.S.A.P. More power to your WEb........ From, Philippines
Microphone Mixer
Saturday, March 17, 2007 2:15:49 PM
All comments are being shown. Show Only Last 10 Comments. Add A Comment

Back To Circuits Page | Mail Me | Search