Three-way Bessel and Butterworth Crossovers | Telex ISP-100 guide

8-14

implementation of Linkwitz-Riley crossovers, for which the ISP-100 has been optimized. The filters marked optional in Figure 8-5 will be explained in the Linkwitz-Riley Crossover section, below.

The lowpass filters LPx (except for the optional LP2) and the highpass filters HPx may each be independently configured as:

Bessel 6 dB/octave (1st-order)

Bessel 12 dB/octave (2nd-order)

Bessel 18 dB/octave (3rd-order)

Bessel 24 dB/octave (4th-order)

Butterworth 6 dB/octave (1st-order)

Butterworth 12 dB/octave (2nd-order)

Butterworth 18 dB/octave (3rd-order)

Butterworth 24 dB/octave (4th-order)

Linkwitz-Riley (Butterworth-Squared) 12 dB/octave (2nd-order) Linkwitz-Riley (Butterworth-Squared) 24 dB/octave (4th-order)

In addition, the cutoff frequency, attenuation, and polarity in the low band, the mid band, and the high band may be independently adjusted, and all of the filters in any band may be bypassed entirely.

The cutoff frequency in each filter is continuously variable from 20 Hz to 20 kHz.

The attenuation in each band is continuously variable from -96 dB to 0 dB, plus mute.

The polarity in each band is selectable as + or - (in-phase or out-of- phase).

Each band may be bypassed, in which case all of the crossover filters in that band will be bypassed while the crossover filters in the other bands will not be affected.

Three-way Bessel and Butterworth Crossovers

Figure 8-6Three-way Bessel & butterworth crossover implementation.

10 July 1998

Image 84

Telex ISP-100 manual Three-way Bessel and Butterworth Crossovers

Contents

ISP-100 This page Left Blank Intentionally Proprietary Notice Procedure for Returns Shipping to Manufacturer for Repair or Adjustment Iii Table of Contents PEQ Installing VUE-IT Processing Components Viii Table of Contents Glossary Standard Quickmap Library An Overview of the ISP-100 About this Manual Customer SupportConventions Used in this Manual Front Panel Features see Figure IntroductionUnpacking Rear Panel Features see Figure Power RequirementsOperating Environment Rack Mounting Card Installation Procedure Battery/module tool Cable Diagrams Analog Audio MIM-1, MIM-2, MOM-1Balanced Input from Balanced Output Balanced Input from Unbalanced Output Balanced Output to Unbalanced Input Digital Audio MDM-1 CardsAES/EBU Input Spdif Input AES/EBU Output Spdif OutputSerial Communications Front Panel RS-232 Rear Panel RS-232 Connections Over 50 Feet 16Connector pinouts July General Purpose Inputs GPI Master Sync Input This page Left Blank Intentionally Case of Problems User Modifications Diagnostics Factory Default Mode Retrieving Version Numbers Retrieving Serial Numbers Changing the Battery Changing the FuseSchurter P/N Telex P/N Denmark Finland Technical Support Helpful Information Shipping to Manufacturer for Repair or Adjustment This page Left Blank Intentionally Components Limiter Property Filters PropertyLowPass Filter Property HighPass Filter Property ISP-100 Component Plots Combine PropertyInput Property Output Property Gate Linkwitz-Riley 3-way Crossover Notch Filter Peaked HighPass Filter System Measurements System Frequency Response System Noise Floor System THD+N Power MIM-1 & MIM-2* Analog Input ModulesPerformance Miscellaneous MOM-1 Analog Output Module MDM-1 AES/EBU Digital I/O Module Performance Sample Rate Converter Engaged1 Performance Sample Rate Converter bypassed Mutes Power Physical Minimum System Requirements Identifying a Serial PortLoading the Software Updating the ISP-100’s Operating System 1OS mismatch dialog 3Open OS file dialog Configuring the Software Dialog box similar to the one in the -6 should appear 9Communications error dialog This page Left Blank Intentionally Starting VUE-IT 1VUE-IT workspace Starting a New Project 2Create new project dialog VUE-IT File System 4New project created Archiving Projects Mounting ProjectsQuickMAP Template Files Component Directory Using VUE-IT Edit see Figure Window see Figure Soft Mute Ramp in Ms System Configurations see Figure Project Manager Properties for the ISP-100 Master Clock SelectionInput Slot Bit Level Project Properties QuickMAP Selection QuickMAP Properties Component Properties Component Export 15Component export dialog QuickSET Manager Component Import Configuring Input Pins Creating New QuickSETsDeleting QuickSETs Selecting the Active QuickSET Testing the GPI Assignments 19 GPI panel QuickMAP QuickMAP Component Bypassing Using the Stereo Control Using the Pad ControlInput Using the Relay Control OutputMute Control Digital I/O Mute RX Status Information Sample Rate ConverterInput Stream Format Input Stream Emphasis Device Status Panel Output Meters Processing Components Using the Knob Using the Text BoxUsing the UP/DOWN Arrows Combine Fine F or Coarse C Control Polarity Control +Mute Control M Bypass Control master Compressor Familiar ControlsCompression Ratio Threshold Attack Time Release TimeKnee Selection Sidechain Source Unfamiliar ControlsDetection Window Crest Factor Sensitivity Metering BypassOvershoot Computation of Average Level Using the Slider Meter Knee Control Ratio ControlSidechain Crossover Two-Way Crossovers July Two-way Linkwitz-Riley Crossovers Three-Way Crossovers Three-way Bessel and Butterworth Crossovers Three-way Linkwitz-Riley Crossovers 7Three-way Linkwitz-Riley crossover implementation July Four-Way Crossovers 8Four-way crossover implementation Four-way Bessel and Butterworth Crossovers 9Four-way Bessel & Butterworth crossover implementation Four-way Linkwitz-Riley Crossovers 10Four-way Linkwitz-Riley crossover implementation LPx HPx = θx LPx + HPx = θ July Three-way Four-wayLow, Low-Mid, Mid, Mid-High and High Controls Link/Unlink Control Class Cutoff FrequencyPassband Gain Fine F or Coarse C Control Cut Attenuation and PolarityAttenuator Processing Components Cut Delay Setting Delay Dither Bit Level Dither Signal Characteristics Dither Bit Level Filter Filter Bands LowPass Filters HighPass Filters LowShelf Filters HighShelf Filters Notch Filters Parametric EQ Filters Center Frequency Bandwidth Boost and Cut Peaked HighPass FiltersPeak Magnitude AllPass Filters Filter TypeActive Band Frequency in Hz Using the Filter Tool Boost/Cut Using the Magnitude Mag. or Phase Control Using the Logarithmic Log. or Linear ControlUsing the 24 dB, 40 dB, 120 dB Controls Gain Trim Isolate Iso Control Gain Gain and Polarity Master Attenuator Fine or Coarse ControlPre-Fader Metering PFM Processing Components Gain Gate Opening Time Closing Time Key ChannelGated Attenuation Keying from Other Channels Attenuation and Threshold Controls Open, Window, Close Controls Limiter 19Limiter component Release Time Unfamiliar Controls Metering Computation of Average Level Fine or Coarse Control Select Selecting the Input Glossary DSP Glossary This page Left Blank Intentionally Identification of Slots and Connectors Applying QuickMAPs MONDOEQ.QMS 2X6CMBC.QMS 2X8COMB.QMS 3X6CMBC.QMS 2X8THRU.QMS 4CHAN.QMS 4X6CMBC.QMS 4X6THRU.QMS 32W.QMS 2WAYS.QMS 23WAY.QMS 22WSUB.QMS 22WFR.QMS 22W2ST.QMS 42WAYS.QMS 4W2FR.QMS LCR.QMS MONO3W.QMS Copyright