DIY audio

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An example of DIY audio: a functioning battery-operated DAC (Digital-to-analog converter) before installation in a box case DIY DAC IMG 1229 061231 134836.jpg
An example of DIY audio: a functioning battery-operated DAC (Digital-to-analog converter) before installation in a box case

DIY Audio, do it yourself audio. Rather than buying a piece of possibly expensive audio equipment, such as a high-end audio amplifier or speaker, the person practicing DIY Audio will make it themselves. Alternatively, a DIYer may take an existing manufactured item of vintage era and update or modify it. The benefits of doing so include the satisfaction of creating something enjoyable, the possibility that the equipment made or updated is of higher quality than commercially available products and the pleasure of creating a custom-made device for which no exact equivalent is marketed. Other motivations for DIY audio can include getting audio components at a lower cost, the entertainment of using the item, and being able to ensure quality of workmanship. [1]

Contents

History

Audio DIY came to prominence in the 1950s to 1960s, as audio reproduction was relatively new and the technology complex. Audio reproduction equipment, and in particular high performance equipment, was not generally offered at the retail level. Kits and designs were available for consumers to build their own equipment. Famous vacuum tube kits from Dynaco, Heathkit, and McIntosh, as well as solid state (transistor) kits from Hafler allowed for consumers to build their own hi fidelity systems. Books and magazines were published which explained new concepts regarding the design and operation of vacuum tube and (later) transistor circuits.

While audio equipment has become easily accessible in the current day and age, there still exists an interest in building and repairing one's own equipment including, but not limited to; pre-amplifiers, amplifiers, speakers, cables, CD players and turntables. Today, a network of companies, parts vendors, and on-line communities exist to foster this interest. DIY is especially active in loudspeaker and in tube amplification. Both are relatively simple to design and fabricate without access to sophisticated industrial equipment. Both enable the builder to pick and choose between various available parts, on matters of price as well as quality, allow for extensive experimentation, and offer the chance to use exotic or highly labor-intensive solutions, which would be expensive for a manufacturer to implement, but only require personal labor by the DIYer, which is a source of satisfaction to them.

Construction issues

Since the 1960s, integrated circuits make construction of DIY audio systems easier, but the proliferation of surface mount components (which are small and sometimes difficult to solder with a soldering iron) and fine pitch printed circuit boards (PCBs) can make the physical act of construction more difficult. Nevertheless, surface mounting is often used, as are conventional PCBs and electronic components, while some enthusiasts insist on using old-style perforated cardboard onto which individual components are hardwired and soldered. Test equipment is readily available for purchase and enables convenient testing of parts and systems. Specifications of parts and components are readily accessible through the Internet including data sheets and equipment designs.

It has become easier to make audio components from scratch rather than from kits due to the availability of CAD software for printed circuit board (PCB) layouts and electronic circuit simulation. Such software can be free, and a trial version may also be used. PCB vendors are more accessible than ever, and can manufacture PCBs in small quantities for the do-it-yourselfer. In fact, kits and chemicals for self-manufacturing one's own PCB can be obtained. Electronic parts and components are accessible online or in speciality shops, and various high-end parts vendors exist. On the other hand, a wide variety of kits, designs and premanufactured PCBs are available for almost any type of audio component.

To construct a device takes more than knowledge of circuits, many would urge that the mechanical aspects of cabinets, cases and chassis' are the most time consuming aspects of audio DIY. Drilling, metalworking and physical measurements are critical to constructing almost any DIY audio project, especially speakers. Measuring equipment such as a Vernier caliper is often essential. Woodworking skills are required to construct wooden enclosures (e.g. for speakers), with some enthusiasts going beyond traditional woodworking to CNC turning, and luxurious veneers and lacquers. Room acoustics solutions are also popular among DIYers, as they can be made with inexpensive and readily available insulating materials, and can be dimensioned to fit each particular room in a precise and aesthetically pleasing way.

DIY audio involves projects directed to audio. Many DIY audio people fancy themselves to be audiophiles. These people use rare and expensive parts and components in their projects. Examples are the use of silver wire, expensive capacitors, non-standard solders of various alloys, and use of parts that have been cryogenically cooled.

Vacuum tube or valve projects are common in audio DIY. While, for mass market audio components, the vacuum tube has been replaced in modern times with the transistor and IC, the vacuum tube remains prominent in specialty high end audio equipment. Thus, interest exists in building components using vacuum tubes, and the vacuum tube is still widely available. There is a wide variety of tubes manufactured nowadays, and many tubes on the market are advertised as NOS; not all of the latter being genuinely NOS. Circuits utilizing tubes often are far less complicated than those utilizing transistors or op-amps. Tube enthusiasts often use transformers, sometimes custom-made ones, or even hand-wind their own transformers using cores and wire of their own choice. Note that vacuum tube projects almost always use dangerously high voltages and should be undertaken with due care.

In case lead-containing solder is used instead of RoHS-compliant solder, appropriate environmental precautions with regard to lead and lead products should be taken.

Tweaking and tweakers

Rebuilt and refinished Magnavox wood speaker using a Dayton 2 way crossover, peerless 6 1/2 inch woofer, and Usher Audio 1 1/8 inch tweeter DIY Rebuilt Vintage Magnavox Speakers.jpg
Rebuilt and refinished Magnavox wood speaker using a Dayton 2 way crossover, peerless 6 1/2 inch woofer, and Usher Audio 1 1/8 inch tweeter

DIY audio can also involve tweaking of mass market components. It is thought that mass market audio components are compromised by the use of cheap or inferior internal parts that can be easily replaced with high quality substitutes. As a result, an audio component of improved characteristics may be obtained for relatively low cost. Some common changes include replacing opamps, replacing capacitors (recap), or even replacing resistors in order to increase signal-to-noise ratio. Changing an audio component in this way is similar to what a tweaker or modder does with a personal computer.

Circuit bending

Circuit bending is the creative customization of the circuits within electronic devices such as low voltage, battery-powered guitar effects, and small digital synthesizers to create new musical or visual instruments and sound generators. Emphasizing spontaneity and randomness, the techniques of circuit bending have been commonly associated with noise music, though many more conventional contemporary musicians and musical groups have been known to experiment with bent instruments. Circuit bending usually involves dismantling the machine and adding components such as switches and potentiometers that alter the circuit.

Cloning and cloners

Another common practice in the DIY audio community is to attempt to clone or copy a pre-existing design or component from a commercial manufacturer. This involves obtaining a lawful public version of, or lawfully reverse engineering, the circuit schematics for the design, and/or even the publicly available PCB layouts. Such a clone will not be a perfect copy since different brands and types of parts (often newer parts) will be used, and mechanical aspects of construction will likely differ. However, the circuit or other distinguishing features should be close to the original.

There are many reasons for wanting to recreate an existing design. The design might be historically important and/or out of production, so the only way to obtain the component is to build it. The design might be very simple so copying it is easily done. The commercial product might be very expensive but its design known, so it may be built for far less than it cost to be purchased. The original design may have some sentimental value to the person building the recreation, and the design built for the memories in one's past. The copy may be made to test or evaluate design concepts or principles in the original.

As an example, a well known clone includes amplifiers using high power integrated circuits, such as the National Semiconductor LM3875 and LM3886. The use of a high power IC as part of a quality audio amplifier was popularized by the 47 Labs Gaincard amplifier, and thus the DIY amplifiers using power ICs are often called chipamps or Gainclones.

Usually cloning additionally involves improving or tweaking (see above) the original design, potentially by using more modern components (in the case of discontinued designs,) higher quality parts, or more efficient board layout.

Operational amplifier swapping

Operational amplifier (op-amps) swapping is the process of replacing an operational amplifier in audio equipment with a different one, in an attempt to improve performance or change the perceived sound quality. Op-amps are used in most audio devices, and most op-amps have the same pinouts, making replacement fairly simple. [2] If the new device's parameters sometimes do not match it can lead to problems like high-frequency oscillation. [3]

Related Research Articles

<span class="mw-page-title-main">Electronics</span> Branch of physics and electrical engineering

Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other electrically charged particles. Electronics is a subfield of physics and electrical engineering which uses active devices such as transistors, diodes, and integrated circuits to control and amplify the flow of electric current and to convert it from one form to another, such as from alternating current (AC) to direct current (DC) or from analog signals to digital signals.

<span class="mw-page-title-main">Amplifier</span> Electronic device/component that increases the strength of a signal

An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the magnitude of a signal. It is a two-port electronic circuit that uses electric power from a power supply to increase the amplitude of a signal applied to its input terminals, producing a proportionally greater amplitude signal at its output. The amount of amplification provided by an amplifier is measured by its gain: the ratio of output voltage, current, or power to input. An amplifier is defined as a circuit that has a power gain greater than one.

<span class="mw-page-title-main">Operational amplifier</span> High-gain voltage amplifier with a differential input

An operational amplifier is a DC-coupled electronic voltage amplifier with a differential input, a (usually) single-ended output, and an extremely high gain. Its name comes from its original use of performing mathematical operations in analog computers.

<span class="mw-page-title-main">Point-to-point construction</span> Making an electronic circuit by directly connecting the leads of the components

In electronics, point-to-point construction is a non-automated technique for constructing circuits which was widely used before the use of printed circuit boards (PCBs) and automated assembly gradually became widespread following their introduction in the 1950s. Circuits using thermionic valves were relatively large, relatively simple, and used large sockets, all of which made the PCB less obviously advantageous than with later complex semiconductor circuits. Point-to-point construction is still widespread in power electronics, where components are bulky and serviceability is a consideration, and to construct prototype equipment with few or heavy electronic components. A common practice, especially in older point-to-point construction, is to use the leads of components such as resistors and capacitors to bridge as much of the distance between connections as possible, reducing the need to add additional wire between the components.

<span class="mw-page-title-main">Audio power amplifier</span> Audio amplifier with power output sufficient to drive a loudspeaker

An audio power amplifier amplifies low-power electronic audio signals, such as the signal from a radio receiver or an electric guitar pickup, to a level that is high enough for driving loudspeakers or headphones. Audio power amplifiers are found in all manner of sound systems including sound reinforcement, public address, home audio systems and musical instrument amplifiers like guitar amplifiers. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers.

<span class="mw-page-title-main">Surface-mount technology</span> Method for producing electronic circuits

Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB). An electrical component mounted in this manner is referred to as a surface-mount device (SMD). In industry, this approach has largely replaced the through-hole technology construction method of fitting components, in large part because SMT allows for increased manufacturing automation which reduces cost and improves quality. It also allows for more components to fit on a given area of substrate. Both technologies can be used on the same board, with the through-hole technology often used for components not suitable for surface mounting such as large transformers and heat-sinked power semiconductors.

<span class="mw-page-title-main">Guitar amplifier</span> Electronic amplifier for musical instruments

A guitar amplifier is an electronic device or system that strengthens the electrical signal from a pickup on an electric guitar, bass guitar, or acoustic guitar so that it can produce sound through one or more loudspeakers, which are typically housed in a wooden cabinet. A guitar amplifier may be a standalone wood or metal cabinet that contains only the power amplifier circuits, requiring the use of a separate speaker cabinet–or it may be a combo amplifier, which contains both the amplifier and one or more speakers in a wooden cabinet. There is a wide range of sizes and power ratings for guitar amplifiers, from small, lightweight practice amplifiers with a single 6-inch speaker and a 10-watt amp to heavy combo amps with four 10-inch or four 12-inch speakers and a 100-watt amplifier, which are loud enough to use in a nightclub or bar performance.

<span class="mw-page-title-main">Valve amplifier</span> Type of electronic amplifier

A valve amplifier or tube amplifier is a type of electronic amplifier that uses vacuum tubes to increase the amplitude or power of a signal. Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers in the 1960s and 1970s. Valve amplifiers can be used for applications such as guitar amplifiers, satellite transponders such as DirecTV and GPS, high quality stereo amplifiers, military applications and very high power radio and UHF television transmitters.

<span class="mw-page-title-main">Microphonics</span>

Microphonics, microphony, or microphonism describes the phenomenon wherein certain components in electronic devices transform mechanical vibrations into an undesired electrical signal (noise). The term comes from analogy with a microphone, which is intentionally designed to convert vibrations to electrical signals.

Founded by David Hafler and Ed Laurent in Philadelphia, Pennsylvania in 1955, Dynaco was an American hi-fi audio system manufacturer popular in the 1960s and 1970s for its wide range of affordable, yet high quality audio components.. Its best known product was the ST-70 tube stereo amplifier. They also manufactured other tube and solid state amplifiers, preamplifiers, radio tuners and bookshelf loudspeakers. Dynaco was liquidated in 1980, and the trademark is now owned by Radial Engineering Ltd.

<span class="mw-page-title-main">Hybrid integrated circuit</span> Type of miniature electronic circuit

A hybrid integrated circuit (HIC), hybrid microcircuit, hybrid circuit or simply hybrid is a miniaturized electronic circuit constructed of individual devices, such as semiconductor devices and passive components, bonded to a substrate or printed circuit board (PCB). A PCB having components on a Printed Wiring Board (PWB) is not considered a true hybrid circuit according to the definition of MIL-PRF-38534.

<span class="mw-page-title-main">Gainclone</span>

Gainclone or chipamp is a type of audio amplifier made by do-it-yourselfers, or individuals interested in DIY audio. It is a design based on high-power integrated circuits, particularly the National Semiconductor Overture series. The Gainclone is probably the most commonly built and well-known amplifier project amongst hobbyists. It is simple to build and involves only a few readily accessible, inexpensive parts. As an amplifier, it is highly regarded by many in the DIY community.

A valve audio amplifier (UK) or vacuum tube audio amplifier (US) is a valve amplifier used for sound reinforcement, sound recording and reproduction.

<span class="mw-page-title-main">Distortion (music)</span> Type of electronic audio manipulation

Distortion and overdrive are forms of audio signal processing used to alter the sound of amplified electric musical instruments, usually by increasing their gain, producing a "fuzzy", "growling", or "gritty" tone. Distortion is most commonly used with the electric guitar, but may also be used with other electric instruments such as electric bass, electric piano, synthesizer and Hammond organ. Guitarists playing electric blues originally obtained an overdriven sound by turning up their vacuum tube-powered guitar amplifiers to high volumes, which caused the signal to distort. While overdriven tube amps are still used to obtain overdrive, especially in genres like blues and rockabilly, a number of other ways to produce distortion have been developed since the 1960s, such as distortion effect pedals. The growling tone of a distorted electric guitar is a key part of many genres, including blues and many rock music genres, notably hard rock, punk rock, hardcore punk, acid rock, and heavy metal music, while the use of distorted bass has been essential in a genre of hip hop music and alternative hip hop known as "SoundCloud rap".

<span class="mw-page-title-main">Turret board</span> Early electronic circuit board design

In electronics, turret boards were an early attempt at making circuits that were relatively rugged, producible, and serviceable in the days before printed circuit boards (PCBs). As this method was somewhat more expensive than conventional "point-to-point" wiring techniques, it was generally found in the more expensive components, such as professional, commercial, and military audio and test equipment. This is similar to cordwood construction.

Luxman is a brand name of Japanese Luxman Corporation (ラックスマン株式会社) that manufactures luxury audio components. Luxman produces a variety of high-end audio products, including turntables, amplifiers, receivers, tape decks, CD players and speakers.

<span class="mw-page-title-main">Valve RF amplifier</span> Device for electrically amplifying the power of an electrical radio frequency signal

A valve RF amplifier or tube amplifier (U.S.) is a device for electrically amplifying the power of an electrical radio frequency signal.

<span class="mw-page-title-main">Tube sound</span> Characteristic quality of sounds from vacuum tube amplifiers

Tube sound is the characteristic sound associated with a vacuum tube amplifier, a vacuum tube-based audio amplifier. At first, the concept of tube sound did not exist, because practically all electronic amplification of audio signals was done with vacuum tubes and other comparable methods were not known or used. After introduction of solid state amplifiers, tube sound appeared as the logical complement of transistor sound, which had some negative connotations due to crossover distortion in early transistor amplifiers. However, solid state amplifiers have been developed to be flawless and the sound is later regarded neutral compared to tube amplifiers. Thus the tube sound now means 'euphonic distortion.' The audible significance of tube amplification on audio signals is a subject of continuing debate among audio enthusiasts.

A semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers before being diced into die, tested, and packaged. The package provides a means for connecting it to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure. Additionally, it helps dissipate heat produced by the device, with or without the aid of a heat spreader. There are thousands of package types in use. Some are defined by international, national, or industry standards, while others are particular to an individual manufacturer.

In electronics, power amplifier classes are letter symbols applied to different power amplifier types. The class gives a broad indication of an amplifier's characteristics and performance. The first three classes are related to the time period that the active amplifier device is passing current, expressed as a fraction of the period of a signal waveform applied to the input. This metric is known as conduction angle (θ). A class A amplifier is conducting through all the period of the signal (θ=360°); Class B only for one-half the input period (θ=180°), class C for much less than half the input period (θ<180°). Class D amplifiers operate their output device in a switching manner; the fraction of the time that the device is conducting may be adjusted so a pulse-width modulation output can be obtained from the stage.

References

  1. Veselinovic, Dejan V. "DIY Pros and Cons". Archived from the original on December 23, 2007.
  2. Auzentech Now Offers Swappable OPAMPs
  3. Swapping Op-Amps... you have checked to see it's stable haven't you ?