# How to make mini 5 channel AUDIO MIXER (for home usage)

#### iamrdb

Joined Jul 31, 2021
6
I want to make a mini audio mixer of 5 channels.
Need circuit diagram

Last edited by a moderator:

#### ronsimpson

Joined Oct 7, 2019
1,465
Inputs, mic or line level?
"Base & Treble"? for each input or only for the output?

#### iamrdb

Joined Jul 31, 2021
6
Inputs, mic or line level?
"Base & Treble"? for each input or only for the output?
No No.. Just volume up down knob only...

#### AnalogKid

Joined Aug 1, 2013
9,353
It's not always about what you want. Make an effort - Search for 'audio mixer schematic' (without quotes) to get dozens (hundreds?) of examples. Find one you think will do what you want - which is a secret since you have given exactly zero details about the application, signals, power source, loads being driven, input voltage levels, etc. - and post it here, and we will help.

ak

#### Ian0

Joined Aug 7, 2020
3,234
It's not always about what you want. Make an effort - Search for 'audio mixer schematic' (without quotes) to get dozens (hundreds?) of examples. Find one you think will do what you want - which is a secret since you have given exactly zero details about the application, signals, power source, loads being driven, input voltage levels, etc. - and post it here, and we will help.

ak
I'll also add to AK's list - "How good does it need to be?"

#### MrChips

Joined Oct 2, 2009
24,180

1) connector
2) level
3) impedance
4) powered or not powered
5) unbalanced or balanced
6) mono or stereo
7) preamp or gain amp
8) level meter
10) mute button

#### Ian0

Joined Aug 7, 2020
3,234
The signal processing is the one thing that HAS been specified:
No tone controls, with or without parametric mid, no graphic equaliser

Then the outputs.
1) Balanced or unbalanced
2) USB
3) SPDIF
4) Effects loop

#### iamrdb

Joined Jul 31, 2021
6
I want to make a mini 5 channel AUDIO MIXER (for home usage).
I am a newbie in this section and have a minimum idea of circuit design that's why I am asking for help.
Mixer Like This ( Watch Here )
1) Components That I want to use :
3.5 mm mono female jack for input
I want to use as input :
(1) Dynamic mic
(2) Condenser Microphone
(3) 3.5mm Stereo Mic
for Stereo to Mono conversion, I will use an adapter

I want to use 5v DC mobile charger as a power supply
Need only one potentiometer for each input line (no bass or treble)
If not possible to make a circuit from the given above details then make an audio mixer for only 3.5mm Stereo Mic

Need only circuit diagram (if possible in EasyEDA) and clear list of components...

#### LowQCab

Joined Nov 6, 2012
1,096
Both the Condenser-Mic, and the Lapel-(Clip-on)-Mic,
(which BTW is not "Stereo"),
require special-considerations, and/or, a Power-Supply-Voltage sent to them for operation.

A "real" "High-End" Condenser-Mic requires "48-Volt-Phantom-Power".
Fortunately, 98% of the "Condenser-Mics" that You will see on-line are
simply constructed to "look-like" an expensive Condenser-Mic.
Some are pure-garbage, and some are actually quite high in performance.
Prices for "real" Condenser-Mics start at around ~$600.oo. This means that you really must have the Microphone FIRST, and then build an appropriate Pre-Amp specifically designed for that particular Model of Microphone. The "Clip-On" "Lapel", or "Lavalier" type Microphone is normally the best choice for getting consistent high-quality Audio for Pod-Casting / making Videos, however, these Microphones usually require Power of some sort. Some have a built-in "Button-Battery", and some require external Power, (usually ~5-Volts from a Computer Mic-Jack). The requirements of the particular Model of Mic that You choose will determine what type of Jack will be required, ( Stereo or Mono ), and whether or not a separate Power-Voltage must be supplied by the Mixer. The "Low-Impedance" "Dynamic" Microphone, ( usually a copy of the ~50-year-old, industry-standard, "Shure-SM-58" ), makes things very simple, and will provide generally "good", "average", performance with no headaches. Limiting your Power choices to ~5-Volts, requires quite a few compromises, but it can be done. Virtually all commercial Microphone-Mixers use a "Plus and Minus ~15-Volt" Power-Supply, (~30-Volts). 5-Volts doesn't give You very much "wiggle-room" to work with, and limits your choices of Amplifiers, (Op-Amps), and will have an Output that is just barely adequate for a standard "Line-Level" Input. A 5-Volt supply is also more likely to create higher Noise-Levels, ( background-Hiss ). This also means that careful setting of Levels between different Amplifier-Stages becomes critical, and may require quite a bit of "tweaking" to obtain acceptable performance levels of Distortion and Noise. A good compromise Power-Supply would be 4- Li-Ion Cells in series, which would make a Plus and Minus ~7.5-Volt Supply, (~15-Volts). Batteries are inherently "quiet", which means less Noise issues to deal with, plus, they're portable. . . . Thread Starter #### iamrdb Joined Jul 31, 2021 6 Both the Condenser-Mic, and the Lapel-(Clip-on)-Mic, (which BTW is not "Stereo"), require special-considerations, and/or, a Power-Supply-Voltage sent to them for operation. A "real" "High-End" Condenser-Mic requires "48-Volt-Phantom-Power". Fortunately, 98% of the "Condenser-Mics" that You will see on-line are simply constructed to "look-like" an expensive Condenser-Mic. Some are pure-garbage, and some are actually quite high in performance. Prices for "real" Condenser-Mics start at around ~$600.oo.

This means that you really must have the Microphone FIRST, and then build an appropriate
Pre-Amp specifically designed for that particular Model of Microphone.

The "Clip-On" "Lapel", or "Lavalier" type Microphone is normally the best choice for
getting consistent high-quality Audio for Pod-Casting / making Videos,
however, these Microphones usually require Power of some sort.
Some have a built-in "Button-Battery",
and some require external Power, (usually ~5-Volts from a Computer Mic-Jack).
The requirements of the particular Model of Mic that You choose
will determine what type of Jack will be required, ( Stereo or Mono ),
and whether or not a separate Power-Voltage must be supplied by the Mixer.

The "Low-Impedance" "Dynamic" Microphone,
( usually a copy of the ~50-year-old, industry-standard, "Shure-SM-58" ),
makes things very simple,
and will provide generally "good", "average", performance with no headaches.

Limiting your Power choices to ~5-Volts, requires quite a few compromises, but it can be done.
Virtually all commercial Microphone-Mixers use
a "Plus and Minus ~15-Volt" Power-Supply, (~30-Volts).
5-Volts doesn't give You very much "wiggle-room" to work with,
and limits your choices of Amplifiers, (Op-Amps), and will have an Output that is
just barely adequate for a standard "Line-Level" Input.
A 5-Volt supply is also more likely to create higher Noise-Levels, ( background-Hiss ).
This also means that careful setting of Levels between different Amplifier-Stages becomes critical,
and may require quite a bit of "tweaking" to obtain
acceptable performance levels of Distortion and Noise.

A good compromise Power-Supply would be 4- Li-Ion Cells in series,
which would make a Plus and Minus ~7.5-Volt Supply, (~15-Volts).
Batteries are inherently "quiet",
which means less Noise issues to deal with,
plus, they're portable.
.
.
.
Thank you very much sir,
I have learned many things from you ..

I have understood what you want to tell,
so decided to make the only mixer for "Clip-On" "Lapel", or "Lavalier" type Microphone only.
, So then what will be the design (how to give power supply them)
the output will be attached with a computer 3.5mm input jack..

Anyone in this forum is also welcome for answering...

#### iamrdb

Joined Jul 31, 2021
6
I want to make a simple clear Microphone circuit. I will use this circuit for use on mobile or computer.
1) The electret mic that I want to use :

2) I want to provide a 5v power supply ( from mobile charger )

#### LowQCab

Joined Nov 6, 2012
1,096
The first point is .....
I can not recommend that You purchase a Microphone from China,
( Banggood, Aliexpress, Ebay, Walmart.com, etc., etc., etc. ),
because You really have no idea of what You are going to get.
It will be super-cheap, but the sellers have NO IDEA of what it is that they are selling,
how it works, what the specifications are, how the Jack is Wired,
how much Voltage it requires, absolutely NO Information at all.

There are probably ~10 or more Jack configurations,
will save You a lot of profanities and throwing of Tools.

The Microphone that I found seems to be reasonably priced,
and has a "no-brainer" Mono-Jack, and specified Power requirements.
( it seems that their Site is temporarily broken, the Link might not work )
https://www.markertek.com/product/ex-503/azden-ex-503-omni-directional-lavalier-microphone

I've just about finished a Schematic for a Mixer specifically designed for this Model of Microphone,
sit tight .............
.
.
.

Last edited:

#### iamrdb

Joined Jul 31, 2021
6
The first point is .....
I can not recommend that You purchase a Microphone from China,
( Banggood, Aliexpress, Ebay, Walmart.com, etc., etc., etc. ),
because You really have no idea of what You are going to get.
It will be super-cheap, but the sellers have NO IDEA of what it is that they are selling,
how it works, what the specifications are, how the Jack is Wired,
how much Voltage it requires, absolutely NO Information at all.

There are probably ~10 or more Jack configurations,
will save You a lot of profanities and throwing of Tools.

The Microphone that I found seems to be reasonably priced,
and has a "no-brainer" Mono-Jack, and specified Power requirements.
( it seems that their Site is temporarily broken, the Link might not work )
https://www.markertek.com/product/ex-503/azden-ex-503-omni-directional-lavalier-microphone

I've just about finished a Schematic for a Mixer specifically designed for this Model of Microphone,
sit tight .............
.
.
.
Thank you, sir, Thank you very much.. from you I have learnt so many things..
I will be grateful to you if you provide me with the diagram of "Schematic for a Mixer specifically designed for this Model of Microphone".

#### Ian0

Joined Aug 7, 2020
3,234
Always used to use Panasonic condenser mic inserts. Never gave any trouble.

#### Audioguru again

Joined Oct 21, 2019
3,514
The specs for the expensive mic has no details about its deviation (usually +/-2dB).
Its frequency response from 30Hz to 18kHz might sound like a muffled and tinny telephone like this:

#### Attachments

• 9.7 KB Views: 9

#### Ian0

Joined Aug 7, 2020
3,234
A flat frequency response is an inherent characteristic of the condensor mic. The difference appears to be mainly in the quality of build - generally whether the JFET gate is welded to the element or whether it is just held in place by the can crimp.
I took one of these apart
https://www.behringer.com/product.html?modelCode=P0118
and found inside what looked suspiciously like a Panasonic condensor mic insert.

One thing to watch out for is that some of the parts designed for telephony have a bass roll-off that starts above 100Hz (to fit with the 300-3400Hz telephone bandwidth)

I've also had some success with MEMS microphones. They have a low-impedance output, and just need a 3.3V supply. They are generally excellent quality, but a bit noisy (-60dB) for professional use.

#### LowQCab

Joined Nov 6, 2012
1,096
Here's the Schematic for a Low-Voltage-Mic-Mixer designed to
provide Bias-Power to Electret-Condenser-Mics.
Dynamic-Mics will probably work too.
If perfect extremely-High-Frequency-Response is important to You,
then You will need Op-Amps that cost ~10-times as much,
but these cheapo-chips should do just fine.
All of the Resistors need to be "Metal-Film", 0.5% tolerance, 1/2-Watt rated,
to keep the background noise to a minimum.
All Capacitors, 1uf and smaller, are Ceramic, and at least 10%,
You get what You pay for.
.
.
.

Last edited: