Summary of apa-4e8
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Page 2 apa-4e8 operator’s manual ta x.
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Apa-4e8 operator’s manual page 3 ta x contents thanks thanks thanks thanks ................................ ................................ ................................ ................................................................ ................................ ...............................
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Page 4 apa-4e8 operator’s manual ta x operating your apa: operating your apa: operating your apa: operating your apa: ................................ ................................ ................................ ................................................................ .....................
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Apa-4e8 operator’s manual page 5 ta x remote connection to remote connection to remote connection to remote connection to your apa your apa your apa your apa ................................ ................................ ................................ ..............................................
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Page 6 apa-4e8 operator’s manual ta x additional informati additional informati additional informati additional information about your apa: on about your apa: on about your apa: on about your apa: ................................ ................................ ................................ .......
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Apa-4e8 operator’s manual page 7 ta x thanks thanks thanks thanks thank you for choosing the apa-4e8 adaptive processing amplifier for your application. Please spend a little time reading through this manual, so that you obtain the best possible performance from the unit and become familiar with its...
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Page 8 apa-4e8 operator’s manual ta x import import import important safety instructions ant safety instructions ant safety instructions ant safety instructions caution: risk of electric shock. Do not open warning: apparatus with class i construction shall be connected to a mains socket outlet with ...
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Apa-4e8 operator’s manual page 9 ta x instructions de securite importantes instructions de securite importantes instructions de securite importantes instructions de securite importantes attention: risque de choc electrique. Ne pas ouvrir attention: appareils de construction de classe i doit être rac...
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Page 10 apa-4e8 operator’s manual ta x declaration of conformity declaration of conformity declaration of conformity declaration of conformity we, the manufacturer: xta electronics limited, the design house vale business park worcester road stourport on severn worcestershire england dy13 9bz acknowl...
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Apa-4e8 operator’s manual page 11 ta x installing your installing your installing your installing your apa apa apa apa:::: unpacking after unpacking the unit, please check it carefully for any damage. If any is found, immediately notify the carrier concerned - you, the consignee, must instigate any ...
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Page 12 apa-4e8 operator’s manual ta x installing your apa: installing your apa: installing your apa: installing your apa: electrical considerations the amplifier is fitted with a universal power supply which will operate world-wide — no user setting is required. Make sure power outlets conform to t...
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Apa-4e8 operator’s manual page 13 ta x installing your apa: installing your apa: installing your apa: installing your apa: mechanical considerations to ensure that your apa performs to specification, it should be mounted in a suitable rack or enclosure as described below. Like all high power amplifi...
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Page 14 apa-4e8 operator’s manual ta x connecting to your connecting to your connecting to your connecting to your apa apa apa apa: : : : audio inputs wiring inputs - the inputs are made via 3-pin xlr connectors, which are electronically balanced and should be connected via a high grade twin core sc...
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Apa-4e8 operator’s manual page 15 ta x speaker outputs wiring the speaker outputs are via neutrik speakon connectors. 2 pole (nl2fc) or 4 pole (nl4fc) connectors can be used. Pin 1+: hot pin 1-: cold additionally channel 1 speakon connector carries channel 2 output on pins +2 & -2 to allow easy bi-a...
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Page 16 apa-4e8 operator’s manual ta x getting to getting to getting to getting to know your know your know your know your apa apa apa apa:::: front panel layout and controls 1: usb ‘otg’ socket: apa works in host mode, so usb memory sticks can be plugged in here to update firmware, download presets...
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Apa-4e8 operator’s manual page 17 ta x front panel layout and controls cntd… 11: status and warning indicators: permanent indication of the following: alarm: illuminates to show any condition apa needs to warn you about — the list of possible warnings is covered on page 52. Ctrl: illuminates when a ...
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Page 18 apa-4e8 operator’s manual ta x rear panel controls and sockets 1: mains input socket: mains connection is via a 32a ”powercon” type plug. Supply voltage is 100-240v ac. This unit must be earthed. 2: gpio socket: connections are via phoenix “mini” connectors. They can be used to provide feedb...
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Apa-4e8 operator’s manual page 19 ta x rear panel status led groups there are two sets of status leds on the rear panel — one set beside the input xlr sockets and one set beside the network sockets. Both sets are tri-colour leds and so can show a variety of information using colour and steady/flashi...
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Page 20 apa-4e8 operator’s manual ta x signal paths and block diagram.
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Apa-4e8 operator’s manual page 21 ta x input sources apa is exceptionally flexible as regards input routing and mixing, and can receive audio from a variety of sources: analogue audio, stereo aes audio, multichannel networked audio, along with internal noise and sine wave generators and audio file p...
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Page 22 apa-4e8 operator’s manual ta x pre-matrix processing apa’s processing is conveniently split between input signal conditioning before it reaches the full mix matrix, and output/loudspeaker specific processing dedicated to each of the four power amplifier channels. With this in mind, the pre-m...
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Apa-4e8 operator’s manual page 23 ta x processed input channel blocks each processed input channel contains the following blocks: delay: over 1000ms available on each input channel in 0.01ms steps. Remember that this delay will affect all outputs that it feeds — those might be local power amplifier ...
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Page 24 apa-4e8 operator’s manual ta x mix matrix to power amp processing channels / network outputs following the input switching and before the power amplifier processing and network outputs, the mix matrix allows full mixing of up to 16 sources to each of the 8 outputs. The 16 sources are derived...
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Apa-4e8 operator’s manual page 25 ta x power amp channels processing blocks each power amplifier channel contains the following blocks: delay: over 1000ms available on each input channel in finer sub-sample 300ns steps. This delay normally is used for driver time alignment and so works at very high ...
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Page 26 apa-4e8 operator’s manual ta x gain:placement of the gain control in the signal path is important as it functions not only as a make-up gain for the compressor if required, but also as a channel gain trim. The front panel gain trim also works at this point (but is separate from this). Progra...
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Apa-4e8 operator’s manual page 27 ta x operating your apa operating your apa operating your apa operating your apa:::: powering up your apa will power up in standby the first time it is connected to the mains supply. The power/home button will be illuminated red. A brief press on the power/home butt...
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Page 28 apa-4e8 operator’s manual ta x hint: during start-up, the mute button leds will flash if they are going to unmute automatically at the end of the sequence. They are active during the entire start-up sequence and can be muted/unmuted at any time if not set as required. Powering down and retur...
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Apa-4e8 operator’s manual page 29 ta x home screen layout the home screen shows you important useful information about your apa. The name of your apa as it appears on the network control software is shown first. If you’ve not chosen a name apa will give it a random one so it can be easily identified...
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Page 30 apa-4e8 operator’s manual ta x user metrics incoming mains monitor your apa uses high resolution converters to measure the incoming mains voltage and instantaneous current draw so that it can adjust output power levels if you have set a current limit, and also to ensure that the mains voltag...
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Apa-4e8 operator’s manual page 31 ta x amplifier temperatures your apa has over 20 temperature sensors, monitoring several points on each individual channel’s circuitry, as well as various points within the power supply, and the output filters. This data is all used to ensure that the amplifier can ...
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Page 32 apa-4e8 operator’s manual ta x quick inputs monitor the led meters on your amplifier always show levels relating to the power amplifier outputs, be this absolute output level, level relative to the limiter, or compressor gain reduction 1 . However, you can also check the incoming levels usin...
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Apa-4e8 operator’s manual page 33 ta x amp channel loads in addition to the more obvious 24 bit 96k analogue to digital converters (adcs) fitted to the inputs of your amplifier for analogue signal conversion, your apa has has eight additional adcs of the same quality fitted directly at the output te...
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Page 34 apa-4e8 operator’s manual ta x auto scrolling of user metrics as explained on each user metrics screen, holding either the back or next key for 2 seconds will toggle between auto mode and manual mode. Auto scrolling mode will switch to the next metrics screen every 5 seconds, and will includ...
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Apa-4e8 operator’s manual page 35 ta x tri colour panel metering the led metering on the front panel of your apa is made up of tri colour led elements, capable of displaying red green or yellow. This allows the meters to dynamically alter their colour and offer much better visual feedback. They can ...
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Page 36 apa-4e8 operator’s manual ta x output channel menu overview pressing one of the output edit buttons allows adjustment and viewing of parameters associated with the power amplifier output channels, including quick gain trim, checking of the limiter threshold and adjustment of the output polar...
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Apa-4e8 operator’s manual page 37 ta x output preset if the selected channel is running a specific preset, its name will be displayed here. Output preset will show the name of the output settings that have been selected either as part of a system preset recall via the amplifier’s front panel, or the...
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Page 38 apa-4e8 operator’s manual ta x system menu overview as the majority of apa’s audio features are designed to be set up and adjusted only by remote control, this makes the navigation of the amplifier’s front panel interface much simpler. The main menu (that is, not an output channel menu or us...
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Apa-4e8 operator’s manual page 39 ta x understanding your apa understanding your apa understanding your apa understanding your apa memories, presets and file structures internal sd card each apa is fitted with an internal 4gb microsd card. This card is not user swappable or accessible. Changing or m...
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Page 40 apa-4e8 operator’s manual ta x if you have a ntfs formatted drive instead and need to reformat it for fat32, remember that you will lose all data stored on the drive. Right click on it in your file manager and choose “format” and make sure “file system” is selected to “fat32” as below. Once ...
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Apa-4e8 operator’s manual page 41 ta x this drive is now suitable for copying and syncing firmware, presets and evacuation messages. The concept of file syncing many users will already be familiar with the concept of file syncing, having used external hard drives for backing up important data on com...
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Page 42 apa-4e8 operator’s manual ta x recalling unit memories the memory structure in your apa is very flexible and allows different parts of the amplifier to be independently controlled via memory recalls without affecting other sections. For example, it is possible to recall settings that just sw...
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Apa-4e8 operator’s manual page 43 ta x to recall a unit memory, press menu and then enter to jump to the recall sub menu: use back and next to scroll through the available unit memories. The name of the memory is shown on the top line of each entry; with the second line summarizing what parts of the...
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Page 44 apa-4e8 operator’s manual ta x upgrading firmware via usb upgrading firmware is a two stage process. The firmware file is first copied onto the /firmware folder on the micro sd card. The required version is then chosen via the front panel interface, and the upgrade initiated. Your apa is cap...
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Apa-4e8 operator’s manual page 45 ta x assuming the amplifier is in standby, it will now enable the usb port and try to detect any connected flash drive. This may take a few seconds so please be patient! Once detected, some details of the drive will be displayed and the options available will be sho...
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Page 46 apa-4e8 operator’s manual ta x now that the firmware has been copied to your apa’s sd card, it can be used to finish upgrading the amplifier. Press menu to drop back to the updates sub menu and navigate to: …and press enter. You will now see a list of all the firmware versions stored in the ...
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Apa-4e8 operator’s manual page 47 ta x mains rms current limiter as your apa is capable of drawing huge amounts of current from the mains supply (in excess of the 32a long-term specified for the “powercon” mains connector), it has a programmable mains current limiter that can be used to prevent exce...
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Page 48 apa-4e8 operator’s manual ta x identify unit to help pick out individual amplifiers in a larger system, a two way identification mechanism is built into your apa. This will flash the led meters in a pattern when enabled, and also flag it in the remote software. This can also be enabled remot...
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Apa-4e8 operator’s manual page 49 ta x default user settings your apa’s non-audio related settings can also be defaulted independently. These include the mains current, the ip address configuration, and anything else that can be adjusted in the unit sub menu (excluding the identify function which ca...
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Page 50 apa-4e8 operator’s manual ta x emergency voice evacuation playback if a suitable file exists in the amplifier’s /wav folder on the sd card, it will be played back on all outputs that have the route from aes c&d enabled. This input is interrupted by the evac playback message when gpi 1 is ena...
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Apa-4e8 operator’s manual page 51 ta x system security overview and locking procedure your apa has a sophisticated security system that consists of three hierarchical levels, which can be populated with any combination of controls to limit access to various parts of the system, both locally and remo...
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Page 52 apa-4e8 operator’s manual ta x system warnings system warnings system warnings system warnings your apa has a multitude of temperature sensors (over 20!) as well as real time high resolution voltage and current measurement converters (24 bit, 96k) to feed back information to the dsp in real ...
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Apa-4e8 operator’s manual page 53 ta x warning message shutdown? What to do… status: mains under voltage no, but close… input voltage below 90v — increase mains supply voltage — can you shorten the mains cable run at all? Status: mains over voltage no, but close… disconnect from supply! Input voltag...
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Page 54 apa-4e8 operator’s manual ta x remote connection to your apa remote connection to your apa remote connection to your apa remote connection to your apa overview full remote control of all your apa’s dsp functionality and monitoring of all aspects of its performance is achieved by connecting i...
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Apa-4e8 operator’s manual page 55 ta x the unit should now be visible to the remote control software, as long as your computer is connected to the same network. Adhoc connections (no dhcp server) it is possible to connect directly to a single apa amplifier without routing through a network. This con...
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Page 56 apa-4e8 operator’s manual ta x the default selection is for automatic ip address selection. To change this to manual, press next to display all the manual set-up parameters. Changes are saved automatically — exit by either pressing menu to drop back through the levels or power/home to get ba...
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Apa-4e8 operator’s manual page 57 ta x looking after your apa: looking after your apa: looking after your apa: looking after your apa: maintenance these maintenance instructions are for use by qualified personnel only. Before any routine maintenance, please ensure that your amplifier is disconnected...
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Page 58 apa-4e8 operator’s manual ta x performance of y performance of y performance of y performance of your our our our apa apa apa apa:::: technical specifications a note about how we measure performance. Amplifier power ratings differ from manufacturer to manufacturer making it very difficult to...
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Apa-4e8 operator’s manual page 59 ta x digital audio parameter value adc and dac sample rate 96khz (oversampling type) adc and dac resolution 24bit accepted aes3 sample rates 44.1khz, 48khz, 96khz, 192khz aes3 resolution 16 to 24bit dsp sample rate 96khz dsp resolution 32bit (floating point) process...
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Page 60 apa-4e8 operator’s manual ta x input power parameter value operating voltage range 90v — 240v 3 230v ac max long term current (1 hour) 16.5arms max long term power (1 hour) 3800w rms max short term current (2 sec) 24.3a rms max short term power (2 sec) 5600w rms 115v ac max long term current...
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Apa-4e8 operator’s manual page 61 ta x output power: continuous performance parameter value all channels driven (230v) rms sine wave long term continuous power with all channels run simultaneously (over an hour assuming 20 degree ambient) (test type 1) 8 ohms 3000w (4 x 750w) 4 ohms 3000w (4 x 750w)...
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Page 62 apa-4e8 operator’s manual ta x power measurement test types test type 1: continuous rms sine wave electronic engineers usually find it easy to measure with constant sine wave tones, so we provide power figures in a continuous rms sine wave format so that measurements can be made and understo...
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Apa-4e8 operator’s manual page 63 ta x additional additional additional additional information about your information about your information about your information about your apa: apa: apa: apa: appendix i: dynamic eq dynamic eq is essentially a compressor or expander that can be set to respond and ...
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Page 64 apa-4e8 operator’s manual ta x mode ii: “cut below” having selected the frequency band to work with, the dynamic eq will listen to this band and act upon it by cutting any frequencies present in it that drop below the predetermined threshold. Consider the example below where the threshold is...
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Apa-4e8 operator’s manual page 65 ta x mode iii: “boost above” this is the other less than traditional mode of operation, offering upward expansion, where the signal is boosted once it reaches the threshold. The example below shows that 1khz filter again, this time with the threshold at -20db. As ca...
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Page 66 apa-4e8 operator’s manual ta x mode iv: “boost below” this mode operates in a slightly unconventional manner insofar as behaving as an ‘upwards expander’, as opposed to the more traditional ‘downwards expander’. What this means is that as the signal drops below the threshold, the selected ba...
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Apa-4e8 operator’s manual page 67 ta x appendix ii: program limiter and peak limiter your amplifier has two levels of dynamic protection on its outputs — a traditional program limiter, and a peak limiter. Program limiter high performance digital limiters are provided for each output with control ove...
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Page 68 apa-4e8 operator’s manual ta x peak limiter the main limitation with traditional dynamics control is the inability of the processing to react truly instantaneously to the signal. One of the most significant advantages of digital signal processing over analogue is the ability to delay the aud...
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Apa-4e8 operator’s manual page 69 ta x the blue waveform shows the output of the dynamics module. The circled peak demonstrates that the processor has missed the first peak above the threshold (as it is very fast and short), but has ‘caught up’ shortly afterwards, keeping all other peaks under contr...
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Page 70 apa-4e8 operator’s manual ta x setting accurate limiter thresholds — program limiter the limiters built into your amplifier are intended to be used for loudspeaker driver protection, as opposed to amplifier protection. The amplifier has additional limiters which can adapt automatically to bo...
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Apa-4e8 operator’s manual page 71 ta x setting accurate limiter thresholds — peak limiter assuming the rms limiter has been set correctly and, just as importantly, attack and release times have been chosen as appropriate to the driver to be protected, the peak limiter is typically set to limit overs...
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Page 72 apa-4e8 operator’s manual ta x appendix iii: parametric filter types and uses a wide selection of filter types has been made available under the peq section when editing input or output filters. Each filter type will be explained in turn in the following section. Standard parametric eq the s...
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Apa-4e8 operator’s manual page 73 ta x high/low shelving eq (high shelf shown) the shelving eq has adjustable frequency, ‘q’ (or bandwidth) and gain controls. These affect a range of frequencies from the turnover freqency as shown in the graph. For a high shelf, frequencies above the turnover freque...
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Page 74 apa-4e8 operator’s manual ta x bandpass filter the bandpass filter has adjustable frequency and‘q’ (or bandwidth) controls. These affect a range of frequencies symmetrically about the centre freqency as shown in the graph, gradually cutting the level, but providing no gain. Remember that ‘q’...
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Apa-4e8 operator’s manual page 75 ta x all pass filter the allpass filter has adjustable frequency and ‘q’ (or bandwidth) controls. These affect the frequency at which the phase effectively flips 180°, and the ‘speed’ at which this transition occurs. The graph shows an allpass filter centred at 1khz...
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Page 76 apa-4e8 operator’s manual ta x low/high pass variable ‘q’ filter (low pass shown) the low and high pass variable ‘q’ filters have adjustable frequency and ‘q’ (or bandwidth) controls. The ‘q’ control adjust the damping of the filter, so that low ‘q’ settings show less overshoot at the turnov...