BASS.NET API for the Un4seen BASS Audio LibraryBASS_BFX_BQF ClassBASS.NET API for the Un4seen BASS Audio Library
Used with BASS_ChannelSetFX(Int32, BASSFXType, Int32), BASS_FXSetParameters(Int32, Object) and BASS_FXGetParameters(Int32, Object) to retrieve and set the parameters of the DSP effect BiQuad filter.
Inheritance Hierarchy

SystemObject
  Un4seen.Bass.AddOn.FxBASS_BFX_BQF

Namespace: Un4seen.Bass.AddOn.Fx
Assembly: Bass.Net (in Bass.Net.dll) Version: 2.4.12.0
Syntax

[SerializableAttribute]
[StructLayoutAttribute(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public sealed class BASS_BFX_BQF

The BASS_BFX_BQF type exposes the following members.

Constructors

  NameDescription
Public methodBASS_BFX_BQF
Default constructor
Public methodBASS_BFX_BQF(BASSBFXBQF, Single, Single, Single, Single, Single, BASSFXChan)
Constructor already setting the members.
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Fields

  NameDescription
Public fieldfBandwidth
Bandwidth in octaves (0.1...4...n), Q is not in use (fBandwidth has priority over fQ). Default = 1 (0=not in use).

The bandwidth in octaves (between -3 dB frequencies for for BANDPASS and NOTCH or between midpoint (dBgain/2) gain frequencies for PEAKINGEQ).

Public fieldfCenter
Cut-off frequency (Center in PEAKINGEQ and Shelving filters) in Hz (1...info.freq/2). Default = 200Hz.
Public fieldfGain
Gain in dB (-15...0...+15). Default 0dB (used only for PEAKINGEQ and Shelving filters).
Public fieldfQ
EE kinda definition of Q (0.1...1...n), if bandwidth is not in use. Default = 0.0 (0=not in use).
Public fieldfS
A shelf slope parameter (linear, used only with Shelving filters) (0...1...n). Default = 0.0.

When fS=1, the shelf slope is as steep as you can get it and remain monotonically increasing or decreasing gain with frequency.

Public fieldlChannel
A BASSFXChan flag to define on which channels to apply the effect.

Default: -1 (BASS_BFX_CHANALL) - all channels.

Public fieldlFilter
Defines which BiQuad filter should be used.
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Remarks

BiQuad filters are second-order recursive linear filters.

BASS_BFX_BQF_LOWPASS:
A low-pass filter is a filter that passes low-frequency signals but attenuates (reduces the amplitude of) signals with frequencies higher than the fCenter frequency. The actual amount of attenuation for each frequency varies from filter to filter. It is sometimes called a high-cut filter, or treble cut filter when used in audio applications. A low-pass filter is the opposite of a high-pass filter, and a band-pass filter is a combination of a low-pass and a high-pass.

BASS_BFX_BQF_HIGHPASS:
A high-pass filter is an LTI filter that passes high frequencies well but attenuates (i.e., reduces the amplitude of) frequencies lower than the fCenter frequency. The actual amount of attenuation for each frequency is a design parameter of the filter. It is sometimes called a low-cut filter; the terms bass-cut filter or rumble filter are also used in audio applications.

BASS_BFX_BQF_BANDPASS:
A band-pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range. An example of an analogue electronic band-pass filter is an RLC circuit (a resistor–inductor–capacitor circuit). These filters can also be created by combining a low-pass filter with a high-pass filter.

BASS_BFX_BQF_NOTCH:
In signal processing, a band-stop filter or band-rejection filter is a filter that passes most frequencies unaltered, but attenuates those in a specific range to very low levels. It is the opposite of a band-pass filter. A notch filter is a band-stop filter with a narrow stopband (high Q factor). Notch filters are used in live sound reproduction (Public Address systems, also known as PA systems) and in instrument amplifier (especially amplifiers or preamplifiers for acoustic instruments such as acoustic guitar, mandolin, bass instrument amplifier, etc.) to reduce or prevent feedback, while having little noticeable effect on the rest of the frequency spectrum. Other names include 'band limit filter', 'T-notch filter', 'band-elimination filter', and 'band-reject filter'.

BASS_BFX_BQF_ALLPASS:
An all-pass filter is a signal processing filter that passes all frequencies equally, but changes the phase relationship between various frequencies. It does this by varying its propagation delay with frequency. Generally, the filter is described by the frequency at which the phase shift crosses 90° (i.e., when the input and output signals go into quadrature — when there is a quarter wavelength of delay between them).

BASS_BFX_BQF_PEAKINGEQ:
A peaking equalizer raises or lowers a range of frequencies around a central point in a bell shape. A peaking equalizer with controls to adjust the level (fGain), fBandwidth (fQ) and center frequency (Hz) is called a parametric equalizer. Peaking Equalizer in BASS_FX can be achieved directly and efficiently by BASS_BFX_PEAKEQ.

BASS_BFX_BQF_ALLPASS:
An all-pass filter is a signal processing filter that passes all frequencies equally, but changes the phase relationship between various frequencies. It does this by varying its propagation delay with frequency. Generally, the filter is described by the frequency at which the phase shift crosses 90° (i.e., when the input and output signals go into quadrature — when there is a quarter wavelength of delay between them).

BASS_BFX_BQF_LOWSHELF:
A low-shelf filter passes all frequencies, but increasing or reducing frequencies below the fCenter frequency by specified amount.

BASS_BFX_BQF_HIGHSHELF:
A high-shelf filter passes all frequencies, but increasing or reducing frequencies above the fCenter frequency by specified amount.

See Also

Reference