11 votes
Accepted

Can I connect multiple electret microphones for better gain?

I am a technician at a boutique mic company. I like to build electret mics in my spare time. You can increase sensitivity, gain, and signal to noise ratio by running multiple electrets in PARALLEL-...
Zachary Alan Stewart's user avatar
9 votes

Why does an electret not pick up sound?

The output amplitude is so low the MCU ADC can't measure anything except the DC bias voltage. Contrary to your assumption, there is no built-in op-amp in the mic capsule. You will need a suitable ...
Justme's user avatar
  • 148k
6 votes

Electret Microphone cannot recognize human voice

The eletret microphone requires a dc bias to enable it to function. However, you only need to detect the audio (ac) signal to amplify and feed to a speaker. The capacitor blocks the dc bias, whilst ...
Bruce Money's user avatar
6 votes
Accepted

(Electret Microphone) Why is input taken from the capacitor?

The capacitor is there to block the DC voltage from feeding into the A/D input of the microcontroller. Inside the electret microphone there will be a FET that can conduct current to GND as sound ...
Michael Karas's user avatar
6 votes

Electret microphone amplification noise

The LM358 is not exactly low noise. You are using a lot of gain. 48000/180= 266. The amplification applies to noise as well as the signal. The bias resistor for the microphone is rather large. This ...
JRE's user avatar
  • 71.4k
4 votes
Accepted

Amplified electret mic gives a lot of low frequency noise

Low frequency noise (~50/60Hz) is mostly caused due to induction of electrical noise into the traces on PCB (or wires, if you're not using a PCB). This is particularly bad with breadboard setups due ...
Pranav's user avatar
  • 56
4 votes
Accepted

How to hook Raspberry Pi with Electret Microphone to detect sound levels in dB?

You selected a microphone board with automatic-gain. This is exactly the OPPOSITE of what you need. You can not measure the actual audio levels when there is something upstream UN-doing all the audio ...
Richard Crowley's user avatar
4 votes

Microphone mute anti-pop circuit works but still picks up a little audio

Check to see if C2 is microphonic by listening while tapping directly on C2. If this is the problem, it can be fixed by replacing C2 with a Mylar capacitor. Ceramic capacitors are often microphonic. I ...
Tom Anderson's user avatar
  • 1,789
3 votes

Microphone mute anti-pop circuit works but still picks up a little audio

You could also try adding a smaller-value capacitor across (in parallel with) the large 100uF capacitor. That would better attenuate high frequency sound that was still leaking through. It is ...
Richard Crowley's user avatar
3 votes

How to hook Raspberry Pi with Electret Microphone to detect sound levels in dB?

You have the wrong thing, first off The automatic gain control (AGC) on your existing microphone-board is not what you want here -- a sound level detector is going to get thrown off by the action of ...
ThreePhaseEel's user avatar
3 votes
Accepted

Microphone supply circuit comparison?

The extra circuits you have researched do not apply if all you are trying to do is interface an electret microphone to a computer mic-in port. Those extra circuits produce a mid-rail voltage (such as ...
Andy aka's user avatar
  • 457k
3 votes
Accepted

How do I determine blocking capacitor and bias resistor values for an Electret Microphone?

Well, with a bias resistor (aka load resistor) of 2k2 (as specified in the data sheet picture in the question), the sensitivity figure (-42 dBV/Pa) means that at a sound pressure level of 94 dB (1 ...
Andy aka's user avatar
  • 457k
3 votes

Feasibility of custom parabolic mic (amplified, bandpass filtered) for use with mobile phone app

You have several problems if you want to power your amplifier and filter through just the bias for the electret microphone. Voltage. You've already mentioned this. There's only a couple of volts ...
JRE's user avatar
  • 71.4k
3 votes
Accepted

Amplify an Electret Microphone using an input Jack 3.5mm

On this Wikipedia page it is explained how an Electret microphone works. What you call the "microphone" is actually the microphone diaphragm itself and a JFET. The JFET is needed to amplify the small ...
Bimpelrekkie's user avatar
  • 80.8k
3 votes

How can an electret microphone have a more or less flat response?

If you are concerned with linearity of voltage response to membrane displacement, the response is linear. Instead of reconstructing the math myself, here is the explanation from openmusiclabs.com: As ...
Ale..chenski's user avatar
  • 40.5k
3 votes
Accepted

Electret microphone signal amplification

This one from Farnell (almost certainly not the one shown in the question) has a clue to the output level: - That clue is inside the red box I added. It tells you this; if a 1 kHz sound signal of 1 ...
Andy aka's user avatar
  • 457k
3 votes
Accepted

3.5 mm Electret Microphone wiring

Generally, electret mics with a 3.5mm TRS (tip-ring-sleeve) male connectors have a connection like the following: Tip and Ring are shorted and connected to Mic+. Sleeve is connected to Mic-. So if ...
Rohat Kılıç's user avatar
3 votes

Can I use a three-wire electret microphone on a two-wire amplifier?

Two wire electret microphones have an FET in a common source arrangement, the source is grounded and the drain is connected to positive through an external resistor. The output is taken from the drain....
GodJihyo's user avatar
  • 23.2k
3 votes
Accepted

Weird noise on a electret amplifier circuit

R5 should be placed directly across the IC without any jumpers. Leads as short as possible. Decouple caps: a) 100nF from pin 7 to pin 4 directly across the IC. No jumpers. b) R1 should be spit into ...
RussellH's user avatar
  • 15k
3 votes

Why does an electret not pick up sound?

Your electret's datasheet specifies: It's been a while, but this is an old way of writing out sensitivity. One bar is \$10^5\:\text{Pa}\$. So \$1\:\mu\text{bar}\$ is \$100\:\text{mPa}\$. Today, we ...
periblepsis's user avatar
  • 8,805
3 votes

What determines an electret microphone voltage?

Some electret microphone capsules come with a preamplifier, and some don't. If your capsule does not come with a pre-amplifier, you should add one with a circuit like this simulate this circuit &...
Math Keeps Me Busy's user avatar
3 votes

Why is a transistor amplifier gain less than expected?

Because your microphone has its own internal JFET pre-amplifier, you should connected the positive terminal to a constant voltage supply (perhaps the same as used in your BJT amplifier, but not ...
Math Keeps Me Busy's user avatar
3 votes

Problems with output signal of a 2nd order low pass Sallen Key filter for an electret microphone

The output of my signal from this circuit through my oscilloscope is an square wave. I don't know what is happening here. Sallen key filters cannot be used when the gain required is this high because ...
Andy aka's user avatar
  • 457k
2 votes

Clap on Clap Off Switch

The author of the article says this: - Condenser Mic basically converts sound energy into electrical energy And this is not true - it's true for a moving coil or moving armature microphone but ...
Andy aka's user avatar
  • 457k
2 votes
Accepted

Speaker noise from preamp circuit

As others have mentioned, that is not a very good circuit. Alas, we can't expect that just because we found it on the internet it will be a decent design. I wold use a circuit more like this one. ...
Richard Crowley's user avatar
2 votes

Electret microphone amplifier for computer using transistor

The first and most obvious thing is that electret microphones need a voltage source to operate. You need to put in a resistor from 5V to the point you have marked "sound.". The recommended value ...
JRE's user avatar
  • 71.4k
2 votes
Accepted

How to get audio from a sensor for an Arduino

The audio detector you have chosen is IMO not viable for your project needs. The KY-038 is a very simple sensor and from it's schematic (shown below) you can see that the gain is adjustable but with ...
Jack Creasey's user avatar
  • 21.7k
2 votes

Electret microphone - How to reduce sensitivity

When you unsolder the microphone, you'll find the layout on the bottom somewhat like the following (here a Panasonic WM-52B): There are two solder pads that are almost split in the middle. In this ...
user107063's user avatar
  • 3,713
2 votes

Electret microphone - How to reduce sensitivity

The "Linkwitz mod" reduces the sensitivity of an electret mic and allows the mic to have very loud sounds (from a drum) with low distortion. You cut the pcb trace that connects the metal ...
Audioguru's user avatar
  • 4,348
2 votes

Rating loudness level with electret microphone

I designed this many years ago: - It was part of an answer to this question. If you ignore the final transistor (Q3) and LED and take the output from across C2 you will have a more linear circuit for ...
Andy aka's user avatar
  • 457k

Only top scored, non community-wiki answers of a minimum length are eligible