Simple Mixer Schematics Simple Mixer Schematics PREAMBLE: I've been cooking audio circuits for so long now I no-longer need a recipe. A lot of the theory I have forgotten over the years because I've just gotten to know the circuits by instinct. But this should serve as something of a guide to designing mixers from scratch. The idea: Most people reading this would be well aware of what a mixer is used for but I'll reiterate here. Audio is of course an AC (Alternating current) signal but if we look at the incoming signals as a frozen moment in time we can represent it as 2 or more DC voltages. If we had two signals to be mixed. When you get to the stage of adding many signals together, the complexity grows. Because each incoming signal has it's own load impedance it is impractical just to wire all of them together and hope for the best. What is required is a little load isolation. This approach also creates another side effect. Generally speaking the pre-amps stage does not provide any gain. And as always.
Audio - Do-It-Yourself Circuits DIY-page Welcome to the Gyraf Audio DIY-page..... Please read this first!! The projects described on these pages are not commercial in any way. Please DO NOT contact us regarding parts or info for the DIY-projects, as we don't sell anything related to these - they're kept strictly non-commercial. 20. Here's the link to the Prodigry-pro forums (AKA GroupDIY) - our meeting place and hangout for all things audio, electronic and DIY. Gyraf Do-It-Yourself Circuits This pages contain information about building your own professional audio equipment. Comments and corrections are more than welcome, but I can't promise to reply to all mail. Disclaimer: Notice that all information, schematics, layouts etc. are supplied "as is", and that we can in no way be held responsible for its acurateness, functionality or even safety. Also you should take extreme caution when working with mains voltages and the very high DC voltages ocurring in tube circuits. Basic safety rules: The G1176:
Fuzz Central -- Making the world a fuzzier place for 5 years 20Hz to 200Hz Variable High-Pass Filter Posted Jan 12, 2012 at 9:39 am The circuit was designed to create a high-pass filter that can be variably change to work with frequency range from 20 Hz to 200 Hz. High Pass Filter – an electronic circuit that allows the passage of high frequencies while opposing any unwanted low frequency components TL072 – a low noise JFET input operational amplifier with features such as common-mode input voltage range, high slew rate, operation without latch up, compensated internal frequency, high input impedance at the JFET input stage, low noise, low total harmonic distortion, protected from output short circuit, low input bias and offset currents, wide common-mode and differential voltage ranges, and low power consumption The operation of the high-pass filter in a stereo system is represented by the functionality of a tweeter where a capacitor is connected in series as it provides the treble audio to the speaker. Source:users.otenet.gr/~athsam/variable_filter.htm
DIY Audio Projects Forum • Simple Passive Tone-Control I have built up quite a collection of headphone amps and now venturing into higher voltage/wattage amps. My workbench/home office now has a variety of sources and amps, but one DIY item that was missing was an EQ of some sort. I have a few preamps, but I really did not want to add any more gain and noise to an already congested system. I drew the amp up in Tina and sim'd the outputs and made only a few minor changes. The tone control sits in between two switch boxes (back to back) so that I have three sources to a switch box, tone control, switchbox, the amps. Since the control is passive it will attenuate about -20db at the baseline and the pivot point is around 800Hz. Single Op-Amp Twin-T Band-Pass and Notch Filter | Simple Circuit Diagram This is a Single Op-Amp Twin-T Band-Pass and Notch Filter circuit. This circuit uses the twin-T topology which requires one or two op amps and three resistors and three capacitors. That’s mean this topology based on a passive (RC) topology. It is not difficult to match the six passive components, but it is critical. we can use single value of capacitance and a single value of resistance to create C3 and R3. Here is the schematic diagram of the circuit: The component values are determined by following equation: Bandpass configuration: C1 = C2 = C R1 = R2 = R R3 = R/2 C3 = 2C Fo=1/(2pRC) R4 and R5 are used to control gain with R4>100*R5 Notch configuration: R1 = R2 = R C1 = C2 = C R3 = R/2 C3 = 2C Fo = 1/(2pRC) R4=R5:HIGH If the components are matched too closely, the bandpass circuit will oscillate.
Limiter Important! New version of this circuit exists. Click here! Why it is important to use a limiter? Audio signals as music or speech have big dynamic ranges. Following circuit is the simplest limiter possible. Technical specifications Supply voltage: 10-14 V stab. Output voltage vs. input voltage (with C8 placed) Schematic diagram Parts list Resistors: R1 - 68 k R2 - 22 k R3 - 180 k R4 - 10 M R5 - 10 k R6 - 47 R R7 - 240 k R8 - 1,5 k R9 - 820 R Capacitors:C1 - 100 p (ceramic) C2 - 1 n (plastic) C3, C6, C12 - 100 n (ceramic) C4, C11, C13 - 100 u (electrolytic) C5 - 0,33 u (tantalum) C7, C8 - 10 u (electrolytic) C9 - 220 n (plastic) C10 - 47 n (ceramic) C14 - 470 n (plastic) Misc. Don't place the C8 if you don't want to use whole dynamic range. PCB layout
Audio projects, circuits and audio kits Muting Transistor Attenuator Circuits and the 2SC2878 by Jim Keith | Among semiconductors, the muting transistor and its audio application is perhaps the most obscure and poorly understood of all. CMoy Headphone Amp by DigiKey | The CMoy headphone amp is a popular headphone amplifier that is small enough to carry everyday and powerful enough to drive headphones at higher levels than normal. Hybrid Headphone Amp Potentially, headphone listening can be technically superior since room reflections are eliminated and the intimate contact between transducer and ear mean that only tiny amounts of power are required. Audio Compression Amplifier /AGC This is an audio compressor/AGC (automatic gain control) with an astonishing 75db input voltage range. Kojak Siren by P. Here is a very simple Kojak siren that is built with two 555 timer ICs and has 2 linear potentiometers that allows the control of sound speed and tone. LA4440 Audio Amplifier Application: Make your own computer speaker system.
Basic BJT Amplifier Configurations Common Base Configuration Here the base is the common terminal. Used frequently for RF applications, this stage has the following properties. Low input impedance, high output impedance, unity (or less) current gain and high voltage gain.Common Collector Configuration This last configuration is also more commonly known as the emitter follower.
Audio Filters -- Theory and Practice Audio Filters - Theory and Practice by Ethan Winer This article first appeared in the August 1981 issue of Recording-engineer/producer magazine. In a previous article I explained that capacitors are essentially frequency-dependant resistors. One type of filter is the high-pass (or low-cut) shown schematically in Figure 1, along with the resultant frequency response. The low-pass filter, shown in Figure 2, is constructed by transposing the resistor and capacitor. A third kind of filter is the band-pass shown in Figure 3. On a parametric equalizer, there is a control for varying bandwidth, or how far from the center frequency the boost and cut action extends. Although the bandwidth in this simple circuit can be changed by varying the ratio of the inductor to the capacitor, a much better approach is to use an op-amp to provide positive feedback. A typical octave graphic equalizer has a Q of 1 on each of its control bands. 1. 2. TABLE 1: Component Values for 60 Hz.
High Quality Sound Mixer High Quality Audio MixerRod Elliott (ESP) Introduction This project is probably the most ambitious so far, and can be expected to be very expensive. On the positive side, it is also capable of excellent performance, and can be tailored to suit your exact specifications. The project is presented in parts, and Part 1 shows the mic/line module and has some background information on noise measurements and the general philosophy behind the project. Description Since the project is presented in stages, this is an index for the various modules, and as the system is developed will also be the place to look for updates and other information. The additional modules, metering and a complete system layout will be added to the list as they are developed. NOTE: There has been a surprising amount of interest in this project, with a common requirement being a smaller version (an almost equally common request has been for a bigger version, too). Projects Index Main Index
Ken Stone's Modular Synthesizer Band Pass Filter for music synthesizers. This module is a simple bandpass filter with manually adjustable center frequency and Q. It is good for setting up artificial resonances for virtual instruments. Personally I find this sort of filter more interesting than the VCF, and as I needed a few more of them in my system I have produced this PCB. A little on how it works: The schematic of the Band Pass Filter. CX on the overlay is simply an optional part to allow easy conversion to an AC coupled output. Construction The component overlay of the earlier version. The component overlay of Rev 1. Before you start assembly, check the board for etching faults. When you are happy with the printed circuit board, construction can proceed as normal, starting with the resistors first, followed by the IC sockets if used, then moving onto the taller components. Take particular care with the orientation of the polarized components, the electrolytics, diodes, and ICs. The original unit uses LM1458 op-amps.
audio schematics(usefull) The following links to circuit diagrams and building projects I have found from other web sites. I have tested only very few of them so there is no guaratee that those circuit will work as expected. I don't have more info on those projects than what you can download from those sites which have the circuits. If you have more questions about those circuits then please mail the questions directly to the person who has designed the circuit or to the people responsible for those web pages. Power amplifiers High power (>30W) 50 Watt Amplifier - easy to build general purpose 50 watt amp Rate this link 60 Watt Into 8 Ohms Power Amplifier - a simple amp to build, uses commonly available parts and is stable and reliable Rate this link Ampli MOSFET - DIY high power MOSFET amplifier 200 Wrms 8 ohms - 350 Wrms 4 ohms Rate this link Ampli MOSFET 360W - This is a circuit for 360 W rms 8 ohms or 550 Wrms 4 ohms powerful amplifier. Car amplifiers Headphone amplifiers Headphone amplifier accessories
An Introduction To 3D Mixing Mixing is arguably the most important stage of the music production process. When done properly, one can do everything from add energy and warmth to a sound to completely alter the feel and flow of an entire piece of music. In my next few tutorials, I will be taking an in depth look at the mixing process to help you gain a better understanding of mixing concepts and in so doing, present one possible workflow scenario to help you streamline the process. For these tutorials I will be using Logic, but the concepts can be applied across the board. 1. What Is 3D Mixing? 3D mixing is a way of thinking of the mixing process in a spatial (3 dimensional) way. Diagram showing the 3 dimensional sound space 2. The first thing we want to do when beginning a mix is to stop writing! To help commit to the mix as a process unto itself (and save CPU) it is recommended to convert all MIDI to audio from the onset at the highest bit depth and sample rate possible. 3. Logic's arrange page The sample rate menu 4.