The decibel (dB) is a logarithmic unit that indicates the ratio of a physical quantity (usually power or intensity) relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities.^[1] A decibel is one tenth of a bel, a seldom-used unit.

The decibel is used for a wide variety of measurements in science and engineering, most prominently in acoustics, electronics, and control theory. In electronics, the gains of amplifiers, attenuation of signals, and signal-to-noise ratios are often expressed in decibels. The decibel confers a number of advantages, such as the ability to conveniently represent very large or small numbers, and the ability to carry out multiplication of ratios by simple addition and subtraction.

The decibel symbol is often qualified with a suffix, that indicates which reference quantity or frequency weighting function has been used. For example, dBm indicates a reference level of one milliwatt, while dBu is referenced to approximately 0.775 volts RMS.^[2]

The definitions of the decibel and bel use base 10 logarithms. The neper, an alternative logarithmic ratio unit sometimes used, uses the natural logarithm (base e).^[3]

A change in power ratio by a factor of 10 is a 10 dB change. A change in power ratio by a factor of two is approximately a 3 dB change.

History[link]

The decibel originates from methods used to quantify reductions in audio levels in telephone circuits. These losses were originally measured in units of Miles of Standard Cable (MSC), where 1 MSC corresponded to the loss of power over a 1 mile (approximately 1.6 km) length of standard telephone cable at a frequency of 5000 radians per second (795.8 Hz), and roughly matched the smallest attenuation detectable to the average listener. Standard telephone cable was defined as "a cable having uniformly distributed resistance of 88 ohms per loop mile and uniformly distributed shunt capacitance of .054 microfarad per mile" (approximately 19 gauge).^[4]

The transmission unit (TU) was devised by engineers of the Bell Telephone Laboratories in the 1920s to replace the MSC. 1 TU was defined as ten times the base-10 logarithm of the ratio of measured power to a reference power level.^[5] The definitions were conveniently chosen such that 1 TU approximately equaled 1 MSC (specifically, 1.056 TU = 1 MSC).^[6] In 1928, the Bell system renamed the TU the decibel.^[7] Along with the decibel, the Bell System defined the bel, the base-10 logarithm of the power ratio, in honor of their founder and telecommunications pioneer Alexander Graham Bell.^[8] The bel is seldom used, as the decibel was the proposed working unit.^[9]

The naming and early definition of the decibel is described in the NBS Standard's Yearbook of 1931:^[10]

Since the earliest days of the telephone, the need for a unit in which to measure the transmission efficiency of telephone facilities has been recognized. The introduction of cable in 1896 afforded a stable basis for a convenient unit and the "mile of standard" cable came into general use shortly thereafter. This unit was employed up to 1923 when a new unit was adopted as being more suitable for modern telephone work. The new transmission unit is widely used among the foreign telephone organizations and recently it was termed the "decibel" at the suggestion of the International Advisory Committee on Long Distance Telephony.
The decibel may be defined by the statement that two amounts of power differ by 1 decibel when they are in the ratio of 10^0.1 and any two amounts of power differ by N decibels when they are in the ratio of 10^N(0.1). The number of transmission units expressing the ratio of any two powers is therefore ten times the common logarithm of that ratio. This method of designating the gain or loss of power in telephone circuits permits direct addition or subtraction of the units expressing the efficiency of different parts of the circuit...

In April 2003, the International Committee for Weights and Measures (CIPM) considered a recommendation for the decibel's inclusion in the International System of Units (SI), but decided not to adopt the decibel as an SI unit.^[11] However, the decibel is recognized by other international bodies such as the International Electrotechnical Commission (IEC).^[12] The IEC permits the use of the decibel with field quantities as well as power and this recommendation is followed by many national standards bodies, such as NIST, which justifies the use of the decibel for voltage ratios.^[13]

Definition[link]

A decibel (dB) is one tenth of a bel (B), i.e., 1B = 10dB. The bel represents a ratio between two power quantities of 10:1, and a ratio between two field quantities of Failed to parse (Missing texvc executable; please see math/README to configure.): \sqrt{10}: 1 .^[14] A field quantity is a quantity such as voltage, current, sound pressure, electric field strength, velocity and charge density, the square of which in linear systems is proportional to power. A power quantity is a power or a quantity directly proportional to power, e.g., energy density, acoustic intensity and luminous intensity.

The calculation of the ratio in decibels varies depending on whether the quantity being measured is a power quantity or a field quantity.

Two signals that differ by one decibel have a power ratio of 1.25892 (or Failed to parse (Missing texvc executable; please see math/README to configure.): 10^\frac{1}{10}\, ) and an amplitude ratio of 1.12202 (or Failed to parse (Missing texvc executable; please see math/README to configure.): \sqrt{10}^\frac{1}{10}\, ).^[15]

Power quantities[link]

When referring to measurements of power or intensity, a ratio can be expressed in decibels by evaluating ten times the base-10 logarithm of the ratio of the measured quantity to the reference level. Thus, the ratio of a power value P₁ to another power value P₀ is represented by L_dB, that ratio expressed in decibels,^[16] which is calculated using the formula:

Failed to parse (Missing texvc executable; please see math/README to configure.): L_\mathrm{dB} = 10 \log_{10} \bigg(\frac{P_1}{P_0}\bigg) \,

The base-10 logarithm of the ratio of the two power levels is the number of bels. The number of decibels is ten times the number of bels (equivalently, a decibel is one-tenth of a bel). P₁ and P₀ must measure the same type of quantity, and have the same units before calculating the ratio. If P₁ = P₀ in the above equation, then L_dB = 0. If P₁ is greater than P₀ then L_dB is positive; if P₁ is less than P₀ then L_dB is negative.

Rearranging the above equation gives the following formula for P₁ in terms of P₀ and L_dB:

Failed to parse (Missing texvc executable; please see math/README to configure.): P_1 = 10^\frac{L_\mathrm{dB}}{10} P_0 \,

.

Since a bel is equal to ten decibels, the corresponding formulae for measurement in bels (L_B) are

Failed to parse (Missing texvc executable; please see math/README to configure.): L_\mathrm{B} = \log_{10} \bigg(\frac{P_1}{P_0}\bigg) \,

Failed to parse (Missing texvc executable; please see math/README to configure.): P_1 = 10^{L_\mathrm{B}} P_0 \,

.

Field quantities[link]

When referring to measurements of field amplitude, it is usual to consider the ratio of the squares of A₁ (measured amplitude) and A₀ (reference amplitude). This is because in most applications power is proportional to the square of amplitude, and it is desirable for the two decibel formulations to give the same result in such typical cases. Thus the following definition is used:

Failed to parse (Missing texvc executable; please see math/README to configure.): L_\mathrm{dB} = 10 \log_{10} \bigg(\frac{A_1^2}{A_0^2}\bigg) = 20 \log_{10} \bigg(\frac{A_1}{A_0}\bigg). \,

The equivalence of Failed to parse (Missing texvc executable; please see math/README to configure.): 10 \log_{10} \frac{a^2}{b^2}

and Failed to parse (Missing texvc executable; please see math/README to configure.): 20 \log_{10} \frac{a}{b}
is one of the standard properties of logarithms.

The formula may be rearranged to give

Failed to parse (Missing texvc executable; please see math/README to configure.): A_1 = 10^\frac{L_\mathrm{dB}}{20} A_0 \,

Similarly, in electrical circuits, dissipated power is typically proportional to the square of voltage or current when the impedance is held constant. Taking voltage as an example, this leads to the equation:

Failed to parse (Missing texvc executable; please see math/README to configure.): G_\mathrm{dB} =20 \log_{10} \left (\frac{V_1}{V_0} \right ) \quad \mathrm \quad

where V₁ is the voltage being measured, V₀ is a specified reference voltage, and G_dB is the power gain expressed in decibels. A similar formula holds for current.

Examples[link]

All of these examples yield dimensionless answers in dB because they are relative ratios expressed in decibels. Note that the unit "dBW" is often used to denote a ratio where the reference is 1 W, and similarly "dBm" for a 1 mW reference point.

• To calculate the ratio of 1 kW (one kilowatt, or 1000 watts) to 1 W in decibels, use the formula

Failed to parse (Missing texvc executable; please see math/README to configure.): G_\mathrm{dB} = 10 \log_{10} \bigg(\frac{1000~\mathrm{W}}{1~\mathrm{W}}\bigg) \equiv 30~\mathrm{dB} \,

• To calculate the ratio of Failed to parse (Missing texvc executable; please see math/README to configure.): \sqrt{1000}~\mathrm{V} \approx 31.62~\mathrm{V}

to Failed to parse (Missing texvc executable; please see math/README to configure.): 1~\mathrm{V}
in decibels, use the formula

Failed to parse (Missing texvc executable; please see math/README to configure.): G_\mathrm{dB} = 20 \log_{10} \bigg(\frac{31.62~\mathrm{V}}{1~\mathrm{V}}\bigg) \equiv 30~\mathrm{dB} \,

Notice that Failed to parse (Missing texvc executable; please see math/README to configure.): ({31.62\,\mathrm{V}}/{1\,\mathrm{V}})^2 \approx {1\,\mathrm{kW}}/{1\,\mathrm{W}} , illustrating the consequence from the definitions above that Failed to parse (Missing texvc executable; please see math/README to configure.): G_\mathrm{dB}

has the same value, Failed to parse (Missing texvc executable; please see math/README to configure.): 30~\mathrm{dB}

, regardless of whether it is obtained from powers or from amplitudes, provided that in the specific system being considered power ratios are equal to amplitude ratios squared.

• To calculate the ratio of 1 mW (one milliwatt) to 10 W in decibels, use the formula

Failed to parse (Missing texvc executable; please see math/README to configure.): G_\mathrm{dB} = 10 \log_{10} \bigg(\frac{0.001~\mathrm{W}}{10~\mathrm{W}}\bigg) \equiv -40~\mathrm{dB} \,

• To find the power ratio corresponding to a 3 dB change in level, use the formula

Failed to parse (Missing texvc executable; please see math/README to configure.): G = 10^\frac{3}{10} \times 1\ = 1.99526... \approx 2 \,

A change in power ratio by a factor of 10 is a 10 dB change. A change in power ratio by a factor of two is approximately a 3 dB change. More precisely, the factor is 10^3/10, or 1.9953, about 0.24% different from exactly 2. Similarly, an increase of 3 dB implies an increase in voltage by a factor of approximately Failed to parse (Missing texvc executable; please see math/README to configure.): \scriptstyle\sqrt{2} , or about 1.41, an increase of 6 dB corresponds to approximately four times the power and twice the voltage, and so on. In exact terms the power ratio is 10^6/10, or about 3.9811, a relative error of about 0.5%.

Merits[link]

The use of the decibel has a number of merits:

• The decibel's logarithmic nature means that a very large range of ratios can be represented by a convenient number, in a similar manner to scientific notation. This allows one to clearly visualize huge changes of some quantity. (See Bode Plot and half logarithm graph.)
• The overall gain of a multi-component system (such as consecutive amplifiers) can be calculated by summing the decibel gains of the individual components, rather than multiply the amplification factors (i.e. log(A × B × C) = log(A) + log(B) + log(C)).
• The human perception of the intensity of, for example, sound or light, is more nearly proportional to the logarithm of intensity than to the intensity itself, per the Weber–Fechner law, so the dB scale can be useful to describe perceptual levels or level differences.

Uses[link]

Acoustics[link]

The decibel is commonly used in acoustics to quantify sound levels relative to a 0 dB reference which has been defined as a sound pressure level of .0002 microbar, or 20 micropascals.^[17] The reference level is set at the typical threshold of perception of an average human and there are common comparisons used to illustrate different levels of sound pressure. As with other decibel figures, normally the ratio expressed is a power ratio (rather than a pressure ratio).

The human ear has a large dynamic range in audio perception. The ratio of the sound intensity that causes permanent damage during short exposure to the quietest sound that the ear can hear is greater than or equal to 1 trillion.^[18] Such large measurement ranges are conveniently expressed in logarithmic units: the base-10 logarithm of one trillion (10¹²) is 12, which is expressed as an audio level of 120 dB. Since the human ear is not equally sensitive to all sound frequencies, noise levels at maximum human sensitivity—somewhere between 2 and 4 kHz—are factored more heavily into some measurements using frequency weighting. (See also Stevens' power law.)

Electronics[link]

In electronics, the decibel is often used to express power or amplitude ratios (gains), in preference to arithmetic ratios or percentages. One advantage is that the total decibel gain of a series of components (such as amplifiers and attenuators) can be calculated simply by summing the decibel gains of the individual components. Similarly, in telecommunications, decibels denote signal gain or loss from a transmitter to a receiver through some medium (free space, waveguide, coax, fiber optics, etc.) using a link budget.

The decibel unit can also be combined with a suffix to create an absolute unit of electric power. For example, it can be combined with "m" for "milliwatt" to produce the "dBm". Zero dBm equals one milliwatt, and 1 dBm is one decibel greater (about 1.259 mW).

In professional audio, a popular unit is the dBu (see below for all the units). The "u" stands for "unloaded", and was probably chosen to be similar to lowercase "v", as dBv was the older name for the same thing. It was changed to avoid confusion with dBV. This unit (dBu) is an RMS measurement of voltage which uses as its reference approximately 0.775 V_RMS. Chosen for historical reasons, the reference value is the voltage level which delivers 1 mW of power in a 600 ohm resistor, which used to be the standard reference impedance in telephone audio circuits.

Optics[link]

In an optical link, if a known amount of optical power, in dBm (referenced to 1 mW), is launched into a fiber, and the losses, in dB (decibels), of each electronic component (e.g., connectors, splices, and lengths of fiber) are known, the overall link loss may be quickly calculated by addition and subtraction of decibel quantities.^[19]

In spectrometry and optics, the blocking unit used to measure optical density is equivalent to −1 B.

Video and digital imaging[link]

In connection with video and digital image sensors, decibels generally represent ratios of video voltages or digitized light levels, using 20 log of the ratio, even when the represented optical power is directly proportional to the voltage or level, not to its square, as in a CCD imager where response voltage is linear in intensity.^[20] Thus, a camera signal-to-noise ratio or dynamic range of 40 dB represents a power ratio of 100:1 between signal power and noise power, not 10,000:1.^[21] Sometimes the 20 log ratio definition is applied to electron counts or photon counts directly, which are proportional to intensity without the need to consider whether the voltage response is linear.^[22]

However, as mentioned above, the 10 log intensity convention prevails more generally in physical optics, including fiber optics, so the terminology can become murky between the conventions of digital photographic technology and physics. Most commonly, quantities called "dynamic range" or "signal-to-noise" (of the camera) would be specified in 20 log dBs, but in related contexts (e.g. attenuation, gain, intensifier SNR, or rejection ratio) the term should be interpreted cautiously, as confusion of the two units can result in very large misunderstandings of the value.

Photographers also often use an alternative base-2 log unit, the f-stop, and in software contexts these image level ratios, particularly dynamic range, are often loosely referred to by the number of bits needed to represent the quantity, such that 60 dB (digital photographic) is roughly equal to 10 f-stops or 10 bits, since 10³ is nearly equal to 2¹⁰.

Suffixes and reference levels[link]

Suffixes are commonly attached to the basic dB unit in order to indicate the reference level against which the decibel measurement is taken. For example, dBm indicates power measurement relative to 1 milliwatt.

In cases such as this, where the numerical value of the reference is explicitly and exactly stated, the decibel measurement is called an "absolute" measurement, in the sense that the exact value of the measured quantity can be recovered using the formula given earlier. If the numerical value of the reference is not explicitly stated, as in the dB gain of an amplifier, then the decibel measurement is purely relative.

The SI does not permit attaching qualifiers to units, whether as suffix or prefix, other than standard SI prefixes. Therefore, even though the decibel is accepted for use alongside SI units, the practice of attaching a suffix to the basic dB unit, forming compound units such as dBm, dBu, dBA, etc., is not.^[23] However, outside of documents adhering to SI units, the practice is very common as illustrated by the following examples.

Voltage[link]

Since the decibel is defined with respect to power, not amplitude, conversions of voltage ratios to decibels must square the amplitude, as discussed above.

A schematic showing the relationship between dBu (the voltage source) and dBm (the power dissipated as heat by the 600 Ω resistor)

dBV

dB(1 V_RMS) – voltage relative to 1 volt, regardless of impedance.^[2]

dBu or dBv

RMS voltage relative to Failed to parse (Missing texvc executable; please see math/README to configure.): \sqrt{0.6}\,\mathrm V\, \approx 0.7746\,\mathrm V

.^[2] Originally dBv, it was changed to dBu to avoid confusion with dBV.^[24] The "v" comes from "volt", while "u" comes from "unloaded". dBu can be used regardless of impedance, but is derived from a 600 Ω load dissipating 0 dBm (1 mW). The reference voltage comes from the computation Failed to parse (Missing texvc executable; please see math/README to configure.): V = \sqrt{600 \, \Omega \cdot 0.001\,\mathrm W}

In professional audio, equipment may be calibrated to indicate a "0" on the VU meters some finite time after a signal has been applied at an amplitude of +4 dBu. Consumer equipment will more often use a much lower "nominal" signal level of -10 dBV.^[25] Therefore, many devices offer dual voltage operation (with different gain or "trim" settings) for interoperability reasons. A switch or adjustment that covers at least the range between +4 dBu and -10 dBV is common in professional equipment.

dBmV

dB(1 mV_RMS) – voltage relative to 1 millivolt across 75 Ω.^[26] Widely used in cable television networks, where the nominal strength of a single TV signal at the receiver terminals is about 0 dBmV. Cable TV uses 75 Ω coaxial cable, so 0 dBmV corresponds to −78.75 dBW (−48.75 dBm) or ~13 nW.

dBμV or dBuV

dB(1 μV_RMS) – voltage relative to 1 microvolt. Widely used in television and aerial amplifier specifications. 60 dBμV = 0 dBmV.

Acoustics[link]

Probably the most common usage of "decibels" in reference to sound loudness is dB SPL, sound pressure level referenced to the nominal threshold of human hearing:^[27]

dB(SPL)

dB (sound pressure level) – for sound in air and other gases, relative to 20 micropascals (μPa) = 2×10⁻⁵ Pa, the quietest sound a human can hear. This is roughly the sound of a mosquito flying 3 meters away. This is often abbreviated to just "dB", which gives some the erroneous notion that "dB" is an absolute unit by itself. For sound in water and other liquids, a reference pressure of 1 μPa is used.^[28]

One Pascal is equal to 94 dB(SPL). This level is used to specify microphone sensitivity. For example, a typical microphone may put out 20 mV at one pascal. For other sound pressure levels, the output voltage can be computed from this basis, except that noise and distortion will affect the extreme levels.

dB(PA)

dB – relative to 1 Pa, often used in telecommunications.^{[citation needed]}

dB SIL

dB sound intensity level – relative to 10⁻¹² W/m², which is roughly the threshold of human hearing in air.

dB SWL

dB sound power level – relative to 10⁻¹² W.

dB(A), dB(B), and dB(C)

These symbols are often used to denote the use of different weighting filters, used to approximate the human ear's response to sound, although the measurement is still in dB (SPL). These measurements usually refer to noise and noisome effects on humans and animals, and are in widespread use in the industry with regard to noise control issues, regulations and environmental standards. Other variations that may be seen are dB_A or dBA. According to ANSI standards, the preferred usage is to write L_A = x dB. Nevertheless, the units dBA and dB(A) are still commonly used as a shorthand for A-weighted measurements. Compare dBc, used in telecommunications.

dB HL or dB hearing level is used in audiograms as a measure of hearing loss. The reference level varies with frequency according to a minimum audibility curve as defined in ANSI and other standards, such that the resulting audiogram shows deviation from what is regarded as 'normal' hearing.^{[citation needed]}

dB Q is sometimes used to denote weighted noise level, commonly using the ITU-R 468 noise weighting^{[citation needed]}

Audio electronics[link]

dBm

dB(mW) – power relative to 1 milliwatt. No reference impedance is assumed, although 600 ohms is common in audio equipment.

dBFS

dB(full scale) – the amplitude of a signal compared with the maximum which a device can handle before clipping occurs. Full-scale may be defined as the power level of a full-scale sinusoid or alternatively a full-scale square wave.

dBTP

dB(true peak) - peak amplitude of a signal compared with the maximum which a device can handle before clipping occurs.^[29] In digital systems, 0 dBTP would equal the highest level (number) the processor is capable of representing. Measured values are always negative or zero, since they are less than or equal to full-scale.

Radar[link]

dBZ

dB(Z) – energy of reflectivity (weather radar), related to the amount of transmitted power returned to the radar receiver; the reference level for Z is 1 mm⁶ m⁻³. Values above 15–20 dBZ usually indicate falling precipitation.^[30]

dBsm

dBsm – decibel measure of the radar cross section (RCS) of a target relative one square meter. The power reflected by the target is proportional to its RCS. "Stealth" aircraft and insects have negative RCS measured in dBsm, large flat plates or non-stealthy aircraft have positive values.^[31]

Radio power, energy, and field strength[link]

dBc

dBc – relative to carrier—in telecommunications, this indicates the relative levels of noise or sideband peak power, compared with the carrier power. Compare dBC, used in acoustics.

dBJ

dB(J) – energy relative to 1 joule. 1 joule = 1 watt second = 1 watt per hertz, so power spectral density can be expressed in dBJ.

dBm

dB(mW) – power relative to 1 milliwatt. When used in the radio field, the dB is usually referenced to a 50 ohm load, with the resultant voltage being 0.224 volts. There are times when spec sheets may show the voltage & power level e.g. −120 dBm = 0.224 microvolts.

dBμV/m or dBuV/m

dB(μV/m) – electric field strength relative to 1 microvolt per meter. Often used to specify the signal strength from a television broadcast at a receiving site (the signal measured at the antenna output will be in dBμV).

dBf

dB(fW) – power relative to 1 femtowatt.

dBW

dB(W) – power relative to 1 watt.

dBk

dB(kW) – power relative to 1 kilowatt.

Antenna measurements[link]

dBi

dB(isotropic) – the forward gain of an antenna compared with the hypothetical isotropic antenna, which uniformly distributes energy in all directions. Linear polarization of the EM field is assumed unless noted otherwise.

dBd

dB(dipole) – the forward gain of an antenna compared with a half-wave dipole antenna. 0 dBd = 2.15 dBi

dBiC

dB(isotropic circular) – the forward gain of an antenna compared to a circularly polarized isotropic antenna. There is no fixed conversion rule between dBiC and dBi, as it depends on the receiving antenna and the field polarization.

dBq

dB(quarterwave) – the forward gain of an antenna compared to a quarter wavelength whip. Rarely used, except in some marketing material. 0 dBq = −0.85 dBi

Other measurements[link]

dB-Hz

dB(hertz) – bandwidth relative to 1 Hz. E.g., 20 dB-Hz corresponds to a bandwidth of 100 Hz. Commonly used in link budget calculations. Also used in carrier-to-noise-density ratio (not to be confused with carrier-to-noise ratio, in dB).

dBov or dBO

dB(overload) – the amplitude of a signal (usually audio) compared with the maximum which a device can handle before clipping occurs. Similar to dBFS, but also applicable to analog systems.

dBr

dB(relative) – simply a relative difference from something else, which is made apparent in context. The difference of a filter's response to nominal levels, for instance.

dBrn

dB above reference noise. See also dBrnC.

See also[link]

• Apparent magnitude
• Cent in music
• dB drag racing
• Equal-loudness contour
• Noise (environmental)
• Phon
• Richter magnitude scale
• Signal noise
• Weighting filter—discussion of dBA

References[link]

External links[link]

• What is a decibel? With sound files and animations
• Conversion of dBu to volts, dBV to volts, and volts to dBu, and dBV
• Conversion of sound level units: dBSPL or dBA to sound pressure p and sound intensity J
• Conversion of voltage V to dB, dBu, dBV, and dBm
• OSHA Regulations on Occupational Noise Exposure
• V_peak, V_RMS, Power, dBm, dBu, dBV online converter at Analog Devices
• Use of the decibel with respect to aerials and aerial systems

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Phil Anselmo
Phil Anselmo performing live with Down in 2008
Background information
Birth name	Philip Hansen Anselmo
Also known as	Anton Crowley
Born	(1968-06-30) June 30, 1968 (age 43)
Origin	New Orleans, Louisiana
Genres	Heavy metal, groove metal, thrash metal, death metal, black metal, sludge metal, hardcore punk, stoner rock, southern metal
Occupations	Musician, songwriter, producer
Instruments	Vocals, guitar, bass guitar, drums
Years active	1983–present
Labels	Housecore
Associated acts	Pantera, Down, Arson Anthem, Superjoint Ritual, Necrophagia
Website	www.philanselmo.com

Philip Hansen "Phil" Anselmo (born June 30, 1968) is an American musician who is best known as the lead singer for the heavy metal band Pantera. He is currently the frontman for the Louisiana-based metal act Down. He is also the owner of Housecore Records and has been a part of many side-projects.

Childhood and early life[link]

Anselmo started life in New Orleans and attended Grace King High School located in the suburb of Metairie.^[1] His father owned and operated a restaurant in Metairie called Anselmo's, which closed in the wake of Hurricane Katrina. Anselmo has said in various interviews that he was very quiet and secluded as a child. He spent some time working on fishing boats as a young man. During a 2002 Ozzfest interview with the radio show Opie and Anthony, Anselmo shared a story that, at the age of 15, he started a fire in his home to scare his sister but accidentally burned the house down in the process.^[2] While a teenager, Anselmo joined the band Samhain (not to be confused with Glenn Danzig's band Samhain). From the early to mid '80s, Anselmo was a member of the band Razor White. While they did have some original material, they played mainly Judas Priest covers.

Primary bands[link]

Pantera[link]

Anselmo performing with Superjoint Ritual at Ozzfest in 2004

Pantera was an unsigned glam metal band, with three self-released albums to their name. In 1986, it was decided by the band to replace singer Terrence Lee, who was primarily a glam metal singer, because they were heading in a different direction musically. Seeking a new frontman to continue on this heavier path, the band was led to 19-year-old Anselmo. In 1987, after several meetings, Anselmo was added to the Pantera lineup. The band was so impressed with Anselmo that they re-recorded some of Terrence Lee's vocals for their latest release. Anselmo relocated to Texas to record Power Metal, which was released in 1988 on the band's own record label, Metal Magic Records. Following the release of Power Metal, the band dropped its glam image and adopted a more casual look. They were signed to a record label by a scout who was stranded due to a hurricane. The band saw the scout at the venue and was disheartened when he left mid-set, but it turned out that the scout had left to phone the record label and to tell them to sign Pantera as soon as possible. Pantera recorded the album Cowboys from Hell in 1990, and a long tour began. The band documented portions of this tour on their first home video, Cowboys from Hell: The Videos, released in 1991.

In 1992, Pantera recorded Vulgar Display of Power. That same year, Pantera released a promo titled Hostile Mixes that contained four songs, three of which were remixes. The first two remixes were done by Justin K. Broadrick of Godflesh and the last by J. G. Thirlwell of Foetus. In 1994, Pantera released Far Beyond Driven, which debuted at #1 in the U.S. In late June, Anselmo was charged with assault following an altercation with a security guard when fans were prevented from getting on stage. Anselmo was released on $5,000 bail the next day.^[3][4] The trial was delayed three times.^[5] In May 1995, he apologized in court, pleaded guilty to attempted assault, and was sentenced to 100 hours of community service.^[6][7]

In 1996, Pantera released their fourth studio album with Anselmo, titled The Great Southern Trendkill. Anselmo recorded the vocal tracks for this album in New Orleans while the other members recorded in Texas. In 1997, Pantera released their first and only official live album titled Official Live: 101 Proof. This album contained two new tracks--"I Can't Hide" and "Where You Come From." In 2000, Pantera released their final studio album, titled Reinventing the Steel. In 2003, Pantera released a best-of album, The Best of Pantera: Far Beyond the Great Southern Cowboys' Vulgar Hits! (titled Reinventing Hell: The Best of Pantera in Europe). The album featured songs from five studio albums with Anselmo, and also included three cover tracks, "Planet Caravan" and "Hole in the Sky," written by Black Sabbath; and "Cat Scratch Fever," written by Ted Nugent. A bonus DVD was also made, containing all the band's music videos. Later that year, Pantera disbanded over communication problems and accusations that Anselmo had abandoned the band.

Following the breakup, Anselmo devoted much of his time to a longtime side project, Superjoint Ritual. Having heard this, the Abbott brothers of Pantera (guitarist Dimebag Darrell and drummer Vinnie Paul) formed Damageplan with former Halford guitarist Pat Lachman on vocals and Bob Zilla on bass. Some fans blame Anselmo for Pantera's breakup, because of statements in the heavy metal press. Anselmo has accused journalists of twisting the facts, publishing what they think sells best. Pantera bassist Rex Brown, widely known as being the one neutral voice in the matter, has blamed both sides for the split.

After Vinnie Paul slammed Superjoint Ritual, saying Anselmo could not even keep his eyes open, Anselmo replied, "I just hear a big and sad yellowbelly crybaby fuckin' knowing that his meal ticket is in a different fuckin' band ... You would have to know those guys to really understand where I was coming from. They're scared of their own fuckin' shadows. And, all that said, I wish them the best of fuckin' luck. I still love 'em."^[8] Anselmo had engaged in a war of words with Dimebag since the fall of Pantera, culminating in the statement "Dimebag deserves to be beaten severely" in the December 2004 edition of the UK's Metal Hammer magazine. Initially, he denied making the statement, but later changed his story in a VH1 Behind the Music special on Pantera, claiming that the comment had been lighthearted and made off the record. However, Vinnie Paul told the press that he had heard the audio files of the interview and that Anselmo had not been misquoted.^[9]

In December 2004, Dimebag Darrell was shot and killed while performing with Damageplan. At the request of Dimebag's family, Anselmo did not attend his funeral.

In a lengthy and emotional video posted on the website community YouTube, Anselmo describes his regret over his previous behavior,^[10] and has written and recorded music dealing with the loss of Dimebag on the new Down record, Down III: Over the Under. The band has dedicated their song "Lifer" to Dimebag.

Down[link]

Down has been Anselmo's main recording and touring band since 2006.

Down is an American heavy metal band formed in 1991 in New Orleans, Louisiana. The band is a supergroup, its various lineups consisting of members and former members of Pantera, Corrosion of Conformity, Crowbar and Eyehategod.

Since its inception, Down has released three studio albums and has gone on hiatus twice to focus on the members' respective bands.

Superjoint Ritual[link]

Superjoint Ritual was a New Orleans metal band formed by Anselmo, Joe Fazzio, and Jimmy Bower in the early 1990s, later to be joined by Hank Williams III, and Kevin Bond. Their style can be considered a mix of groove metal and hardcore punk. Bands like Venom, Slayer, Celtic Frost, Voivod, and Darkthrone have also been noted as influences. The name Superjoint Ritual comes from a lyric in the Darkthrone song, "The Pagan Winter". According to Bower, Anselmo wrote 70-80% of the group's music. During their time together they released two full length albums on Sanctuary Records, Use Once and Destroy in 2002 and A Lethal Dose of American Hatred in 2003.

Active side projects[link]

Arson Anthem[link]

Arson Anthem is a Southern hardcore punk project that originated when Eyehategod singer Mike Williams moved into Anselmo's spare apartment after losing all his possessions in the aftermath of Hurricane Katrina. The two spent countless hours listening to Anselmo’s collection of early hardcore bands. They began jamming with Hank III and Collin Yeo, who were united by their desire to have a hardcore/crust punk band of their own.^[11] The Arson Anthem lineup features Mike Williams on vocals, Phil Anselmo on guitar, Hank III on drums, and Collin Yeo on bass.

Defunct side projects[link]

Anselmo performing with Down in 2006

Christ Inversion[link]

Christ Inversion was formed in 1994. The group was a short-lived black metal project formed by Anselmo where he played guitar under the name "Anton Crowley". Most of their lyrics were based on horror films and Satanism. The band recorded two demos in 1994 and 1995 respectively and then disbanded without ever recording a full-length album. Many years later, songs from the first demo were put on an 8-track compilation and released through Anselmo's own Housecore Records on October 28, 2008.

Southern Isolation[link]

The band released one EP called Southern Isolation. It originally contained four songs, but was later re-released with a fifth bonus track. The band consisted of Stephanie Opal Weinstein on vocals and guitars, Anselmo on vocals, backing vocals and guitars, "Big" Ross Karpelman (of Clearlight) on keyboards, and Sid Montz (of Crowbar) on drums.

One rare track called "Faded" has been credited to Southern Isolation on the Manson Family Soundtrack, which is due to be released on Anselmo's Housecore label.

Viking Crown[link]

Viking Crown was a short-lived and essentially solo side project started by Anselmo in the mid-90s. The members of the band are Anselmo (under the pseudonym Anton Crowley) on guitars, bass and drums; Killjoy on vocals; and Opal Enthroned (Stephanie Opal Weinstein) on keyboards. On their first album Unorthodox Steps of Ritual, Anselmo played every instrument and laid down his own vocals. The band never performed live.

Eibon[link]

Eibon was a very short-lived supergroup which Anselmo participated in from 1998 to 2000. The group featured Killjoy, Fenriz, Satyr, and Maniac. The project has been put on indefinite hiatus and to date has only released a single track, Mirror Soul Jesus, which appeared on the 'Moonfog 2000: A Different Perspective' compilation in 2000. The band is on Satyr's record label 'Moonfog Productions'.

Guest appearances[link]

In 1993 Anselmo produced Crowbar's self titled album and recorded backing vocals on some of the tracks.

In 1996 Anselmo recorded guitars on two songs ("Van Full of Retards" and a cover of Manowar's "Gloves of Metal") and contributed vocals/backing vocals on 18 songs for Anal Cunt's 40 More Reasons to Hate Us album.

In 1996 Anselmo recorded backing vocals for tracks on Crowbar's Broken Glass album.

Also in 1996, Anselmo provided vocals on Soilent Green's album Sewn Mouth Secrets. Although not credited, he is given thanks in the liner notes.

In 1998 Anthrax released the album Volume 8: The Threat Is Real. Anselmo provided backing vocals on track 8 ("Killing Box"). Also, his Pantera bandmate Dimebag Darrell played guitar solos on tracks 3 ("Inside Out") and 7 ("Born Again Idiot").

In 1998 Anselmo sang a duet ("By the River") on Vision of Disorder's Imprint album.

In 2000 Tony Iommi released a collaborative album with various well known vocalists. Initially, Anselmo was going to co-create an entire album with Iommi, but due to tour schedules it never happened. Anselmo managed, however, to lay down some tracks for Iommi's album. Iommi and Anselmo wrote and recorded three tracks together, "Time Is Mine", "The Bastard", and a third unknown track. Iommi picked "Time Is Mine" for the album. "The Bastard" was never officially released, but can be found online.^[12] The third unknown track is now highly sought after by fans of both artists.^[13]

In 2001 Anselmo provided vocals for "HFFK" on Biohazard's Uncivilization album.

On March 6, 2006, Anselmo made an appearance along with Guns N' Roses and Velvet Revolver bassist Duff McKagan and the surviving members of Alice in Chains at a VH1's Decades Rock Live concert, in honor of fellow Seattle musicians such as Alice in Chains' Layne Staley and Ann and Nancy Wilson of Heart

In 2008 Anselmo recorded vocals for the Mahakali album by Jarboe. The track is sparse musically, features a raw vocal delivery by Anselmo, and a short spoken-word segment.

Further reading[link]

Anselmo playing guitar for Eyehategod during Hellfest 2009

Anton Crowley persona[link]

In the mid-90s, Anselmo began to record for several side projects under the pseudonym Anton Crowley, most notably with Viking Crown. The name Anton Crowley is taken from Aleister Crowley (British occultist) and Anton LaVey (Founder and High Priest of the Church of Satan).

In 1997, Necrophagia frontman Killjoy reformed his band with Phil Anselmo on guitars. Using the Anton Crowley name, Anselmo appeared on the 1998 Holocausto de la Morte album, the 1999 Black Blood Vomitorium EP, and finally the 2001 Cannibal Holocaust EP, which featured Opal Enthroned (then Anselmo's wife) on keyboards.

Housecore Records[link]

Anselmo started his own record label called Housecore Records, to release material by his many side projects and from other bands he supported.^[14] For a time Housecore was merged with Baphomet Records, owned by Philip's friend and ex-bandmate Killjoy of Necrophagia, to form Baphomet/Housecore Records. They have since split.^[15]

House of Shock[link]

Anselmo, together with Steve Joseph, Ross Karpelman and Jay Gracianette, started the House of Shock, a Halloween-themed attraction. Initially, it began in Jay Gracianette's backyard, but was later moved to a large warehouse outside New Orleans that has been converted into an interactive haunted house with 300+ volunteer workers. The attraction has raised money for the Childrens Hospital of New Orleans, the Parish Police Bullet Proof Vest Fund, and the Greater New Orleans Riding Rehabilitation Center.^[16] Anselmo played the role of a part-time actor when his schedule permitted.^[17] Anselmo is no longer involved with the attraction.^[1]

John Kaplan photo essay[link]

Anselmo was featured in the John Kaplan photo essay, 21, which was awarded the Pulitzer Prize for Feature Photography. The photographer documented the lifestyles of 21-year-old Americans. Two pictures of Anselmo were included, one with a snake draped over his shoulders and the second as his head is being shaved to reveal a tattoo.

[edit] The Manson Family movie

Anselmo can be heard in the Jim Van Bebber movie The Manson Family as the voice of Satan. The soundtrack for this movie also contains music from several of Anselmo's bands.

Accusations of racism[link]

Since the mid-90s Anselmo has occasionally been accused of being racist, an accusation that he has denied on numerous occasions.

During a Pantera concert in 1995 at the Montreal Verdun Auditorium, Anselmo gave a speech during a break in the performance.^[18] During this speech, Anselmo stated that Pantera was not a racist band, but security personnel and some people who attended the performance found parts of what Anselmo said to be racist. Following this, Anselmo released an open letter apologizing for any offense that he may have caused during this speech.^[19]

During an interview in August 2003, Anselmo stated in regards to the racist accusations, "I’m anything fucking but, I know there’s shitty people and beautiful people on both sides of the spectrum – black and white. And I know for an absolute fucking fact there’s good Middle Eastern people who live here. And I know there’s good Oriental people. But if I’m writing a song and it has to touch on the negatives of certain issues, I’m not gonna beat around the fucking bush and fence-ride – especially with Superjoint. Before, with Pantera, I had to be slightly careful. Now I don’t. And I can see from the enthusiasm in the audiences that we’re on our way to something extremely relevant – something on top of anywhere anybody thinks we might go."^[20]

Personal life[link]

On October 31, 2001, Anselmo married his longtime girlfriend Stephanie Opal Weinstein. That same year they created an acoustic band called Southern Isolation. Anselmo and Weinstein divorced in 2004.

Anselmo is currently in a relationship with Kate Richardson, who also helps with the running of his record label, Housecore Records.^[1] Anselmo currently resides in a rural property in Louisiana.^[1] He keeps a number of animals, including dogs, cats and a variety of birds.^[1] Anselmo had a pet rottweiler named Dracula that died in 2009.^[21]

Interests[link]

Anselmo owns an extensive collection of several thousand horror films and possesses an encyclopedic knowledge of horror films and horror culture.^[22] Anselmo has an interest in the sport of boxing.^[23] He owns hundreds of fight DVDs and used to take a boxing trainer on tour with him.^[23] He has written articles as a columnist for the Boxing Insider website.^[24] Anselmo is a New Orleans Saints fan.^[25] Anselmo has interviewed Saints player Jeremy Shockey and has helped to coach a youth team at the request of Saints team ambassador Michael Lewis during a visit to the teams practice facility.^[1]

Drug abuse[link]

On July 13, 1996, at the 'Coca-Cola Starplex' in Dallas Texas, Anselmo went into cardiac arrest due to a heroin overdose after a show. Paramedics revived Anselmo and he issued a press release four days later saying, "I, Philip H. Anselmo...injected a lethal dose of heroin into my arm, and died for four to five minutes".^[26]

According to Anselmo, he had been suffering constant pain due to a back injury dating back to the mid-1990s. To ease the pain, he drank heavily, abused painkillers and muscle relaxants, and used heroin.^[1] The medication affected his onstage performances and caused slurred speech.^[1]

Since 2005, Anselmo has stopped using hard drugs, initially so that he could be cleared for surgery on his back.^[1]

Surgery[link]

On November 21, 2005, Anselmo underwent surgery to repair severe damage to his back caused by degenerative disc disease.^[1] The surgery was successful, and after several months of recuperation and rehabilitation Anselmo returned to recording and touring.^[1] Anselmo has stated that he still occasionally experiences pain due to the back injury but much less than prior to the surgery.

In early 2009, Anselmo underwent knee surgery. He made the following statement in regards to the injury:

"It was a semi-torn ACL [anterior cruciate ligament, one of the four major ligaments of the knee] and a semi-torn meniscus [a common knee injury]." Anselmo also stated: "With plans to do some jamming during the healing process, trust me, Down will return."^[27] Anselmo originally acquired the injury at a gig prior to the Monsters of Rock festival in England in 1994, after jumping from a speaker cabinet.^[28]

Influences[link]

Anselmo was mainly influenced by Judas Priest,^[29] Slayer,^[30] Hellhammer^[29] and Venom.^[29] He pays tribute to two of his favorite bands in the lyrics of the Pantera song "Goddamn Electric", singing "your trust is in whiskey and weed and Black Sabbath"; in the second verse, the lyric is tweaked to "whiskey and weed and Slayer". Anselmo states that his main vocal influence is Iron Maiden singer, Bruce Dickinson.^[31]

Discography and filmography[link]

References[link]

External links[link]

• Phil Anselmo at the Internet Movie Database
• Phil Anselmo's official webpage