Inputs Format 48

Build your own mixer!

A high-end microphone preamplifier, with several innovative features, specially designed for best possible sound reproduction.

INPUT SECTION:

The XLR input (MIC IN) can receive balanced signals from -63 dBu to +18 dBu. (A range of 81 dB, which therefore permits connection of any audio signal.)
The GAIN knob will amplify a weak signal to a nominal level of 0dBV, or attenuate a stronger signal, so that a nominal signal of 0dB is always present at the output of the mic input amp.
The VU level meters display the amount of Gain set. The headroom from input to output enables fairly strong overloads to be absorbed by the mixer’s electronics, without producing distortion. Gain can therefore be set so that the red “overload” occasionally shows.
The +15dB and MIC-LINE buttons help control the Gain. The +15dB button is automatically excluded when the MIC-LINE button is pressed (as it doesn’t make sense to amplify and attenuate a signal at the same time). Depressing the MIC-LINE button to “line position” (green light) and setting the Gain on “U” (unity gain) means that the mic preamp will neither amplify nor attenuate the signal. This is the correct setting for nominal 0 dB signals, or line signals from professional devices like limiters, effect units or recorders.
The PHASE button (ø) swaps the “hot” and “cold” aspects of the input signal, inverting the signal’s phase 180°. Helpful if two microphones are positioned at a distance, or reverse-faced (i.e. for top and bottom snare drum miking).
Depressing the P 48 button (blue light) delivers 48V of phantom power to the microphone, which, in most cases will be a condenser, or active ribbon mic. Only use this button for mics that you know need phantom power in order to work.
The low cut button (ƒ) limits low frequencies at 100Hz/second order, removing unwanted low frequencies from “boomy” signals. It is also helpful in shaping signals from smaller instruments (violin, mandolin etc).
The INSERT-DIRECTOUT button works in a similar way to that on other mixers, while offering extra possibilities with an additional bypass switch: If the INSERT DIRECTOUT button is not depressed (i.e. off, white light), the signal will not be interrupted by the entry of a phone jack into the Insert connector. If the INSERT DIRECTOUT button is depressed (i.e. on, red light), the signal will be interrupted and the Insert will work in the usual way.
The resonance filter (a kind of notch filter) is gradually adjustable over its attenuation level. If set to “flat” during recording, the filter will be totally bypassed, having no effect on the incoming signal. The filter is designed to avoid, or at least attenuate, feedback on acoustic instruments that are mic’d up in live situations using pickups such as the SCHERTLER DYN series. The 150Hz-240Hz button enables frequency choice: When the button is not depressed (green light) the filter attenuates at 150 Hz. When depressed, (blue light) the filter attenuates at 240 Hz. Keeping the RESONANCE button set to the far left on FLAT means that the filter will not be active. When the RESONANCE button is turned slowly clockwise, the filter gradually attenuates at the chosen frequency.Filters. Innovative filter circuitry enables loss of sound to be kept to an absolute minimum.
The filter section is bypassed (white light) or activated (green light) via the EQ ON button: Helpful for comparing a filter configuration with unfiltered sound. The EQ ON button does not bypass the RESONANCE filter. The HI knob enables the high range of the audio spectrum (5kHz to 20kHz) to be tuned from +/- 16dB with a slope of 18dB / octave. The MID knob, together with the MID FREQ knob, acts on frequencies from 250 Hz to 3.2 kHz, with amplification or attenuation of +/- 14 dB. The LOW filter knob enables signal adjustment from +/- 16dB within a range of 20Hz to 300Hz, with a slope of 12dB / octave. Flat filter positions are indicated by detents at the mid position of each knob.
The CHANNEL ON button connects or disconnects the output routing for all outputs (AUX 1, AUX 2, AUX 3 and L/R), except the PFL routing. Similar to the MUTE button on other mixers, its functionality is however reversed. When the CHANNEL ON button is depressed, all outputs are connected. Also, whereas a MUTE normally only disconnects the L/R routing (the channel’s fader), this unit’s CHANNEL ON button affects all outputs. Note: Even if the CHANNEL ON button is in the switched off position (white light), the PFL and INSERT will still be ready to function, (as shown by the white lights on their respective buttons), even though all other button lights are off.
Three AUX SEND knobs enable independent level control of each send (AUX 1, AUX 2, AUX 3). The sends can also “read” signals pre or post fade, through the use of switch buttons. If a button is not depressed (white light), the signal arrives “post fade” i.e. while the relevant auxiliary level is controlled by its level knob, the final outcome is also influenced by the channel fader’s position.If a button is depressed (red light), the signal arrives “pre fade” and is sent to the AUX master without being affected by the channel fader’s position or movement. Note: To benefit from all the AUX sends (and other additional options), a MASTER AUX unit is required as well as the MASTER L/R unit. The MASTER L/R unit only receives AUX 1 and is intended for a basic configuration, for example, when only one auxiliary send is needed to operate a reverb device.
PFL BUTTON. The PFL can only be operated through the MASTER AUX unit. As well as being a traditional PFL (pre fade listen), it also serves as a fourth AUX send (without the possibility to set any level). Signals from any channels with an activated PFL (red light) will be mixed in the MASTER AUX unit and sent to the PFL output, controlled by the PFL fader on the master AUX unit. Note: The PFL section still runs if the CHANNEL ON button is deactivated (white light).
L / R FADER section. In most cases, the signal going through here will be mixed in the L/R Master before appearing on the main L/R outputs that drive the recording device or the front-of-house PA speakers. Operating the L/R fader section is the same as on other mixing consoles.
The PAN pot enables signal to be sent to the Left or Right channel by turning it in the appropriate direction. At the pot’s mid position, the signal flows to both channels at maximum level.

Input Impedance 4.7kohm
Maximum input level: +4dBu (@1kHz ; THD <0.5%) (MIC MODE)
+26dBu (@1kHz ; THD <0.5%) (LINE MODE)
Maximum output level (trough L/R): +27dBu (@1kHz ; THD <0.5%)
Gain range: 18 to 63dB (MIC MODE)
-9 to 20dB (LINE MODE)
Total Gain (trough L/R): 72 dB
Frequency response: (-3dB) 16Hz to125 kHz
Low cut: (-3dB) 100 Hz (Shelving, 2nd order)
Reson attenuation: 10dB @ 150 Hz / 240 Hz
Low EQ: 460 Hz (Shelving) -20dB / +15dB
Parametric Mid EQ: 250 Hz – 3 kHz -15dB / +15dB
High EQ: 1.2 kHz (Shelving) -12dB / +12dB
Equivalent input noise (EIN): 122,5dB (Insert, 60dB Gain, 150ohm)
Distortion (THD+N; @1kHz)
-30dBu input level
0dBu output level:
0.13% (2nd harmonic)
0.06% (3rd harmonic)
0.015% (4th harmonic)
0.008% (5th harmonic)
Power consumption: 4W (80mA)
Size & Weight: 36x58x475mm ; 0,5 kg
Blockdiagram

The Microphone In Ultra Low Noise (ULN) unit is designed for use with microphones that have a weaker signal (such as ribbon mics), as well as for professional recording applications where the lowest possible noise is required.

Featuring an improved Signal to Noise Ratio, with 4dB less noise, this mic input module adds further flexibility to the ARTHUR mixer.

All other features and specifications are as for the standard Mic Input Unit (Format48).

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Input Impedance 4.7kohm
Maximum input level: +4dBu (@1kHz ; THD <0.5%) (MIC MODE)
+26dBu (@1kHz ; THD <0.5%) (LINE MODE)
Maximum output level (trough L/R): +27dBu (@1kHz ; THD <0.5%)
Gain range: 18 to 63dB (MIC MODE)
-9 to 20dB (LINE MODE)
Total Gain (trough L/R): 72 dB
Frequency response: (-3dB) 16Hz to 125 kHz
Low cut: (-3dB) 100 Hz (Shelving, 2nd order)
Reson attenuation: 10dB @ 150 Hz / 240 Hz
Low EQ: 460 Hz (Shelving) -20dB / +15dB
Parametric Mid EQ: 250 Hz – 3 kHz -15dB / +15dB
High EQ: 1.2 kHz (Shelving) -12dB / +12dB
Equivalent input noise (EIN): 128,7dB (Insert, 60dB Gain, 150ohm) (ULN model)
Distortion (THD+N; @1kHz)
-30dBu input level
0dBu output level:
0.13% (2nd harmonic)
0.06% (3rd harmonic)
0.015% (4th harmonic)
0.008% (5th harmonic)
Power consumption: 4W (80mA)
Size & Weight: 36x58x475mm ; 0,5 kg
Blockdiagram

The unit’s wide gain control and input impedance control (a novel feature) enables instruments to be directly connected to the mixer without external preamps, pedals or guitar amps.

YELLOW is similar to the Microphone Input unit, differing only in its input section:

The unbalanced phone plug input can receive signals from -42dbu to +9dBu. (A range of 51 dB, which therefore permits connection of any musical instrument pickup.)
The GAIN knob amplifies a weak signal to a nominal level of 0dBV, or attenuates a stronger signal, so that a nominal signal of 0dB is always present at the output of the mic input amp.
The VU level meters display the amount of Gain set. The headroom from input to output enables fairly strong overloads to be absorbed by the mixer’s electronics, without producing distortion. Gain can therefore be set so that the red “overload” occasionally shows.
For active instruments with a very strong output, depressing the PAD button (green light) will attenuate the signal by 15 dB.
The 10V button delivers the necessary 10-volt supply for all SCHERTLER electrostatic pickups (STAT- and BASiK series), enabling direct connection to the unit without using the pickup’s original preamp. The 10V button can also be used for connecting unbalanced electret microphones.
The PHASE button (ø) swaps the “hot” and “cold” aspects of the input signal, inverting the signal phase 180°. Helpful if a pickup is combined with a microphone (going through its own mic unit).
The LOW CUT button limits low frequencies at 100Hz/second order.
The IMPEDANCE knob changes the input impedance from 22k to 1M ohms, as the knob is turned from low to hi. For active instrument pickups it should be set to low. For magnetic pickups it should be set between the extremes. For piezo pickups it should be set to hi. Magnetic pickups in particular can benefit from a correctly adjusted input impedance.

The signal flow from input to fader (INSERT, EQ, CHANNEL ON / OFF, AUX SEND, PAN and PFL) is otherwise identical to that of the MIC INPUT unit. For further information, please read the Microphone Input Unit web page.

Input Impedance variable from 20 kohm to 800 kohm
Maximum input level: +24dBu (with PAD ON @1kHz ; THD <0.5%)
Maximum output level (trough L/R): +27dBu (@1kHz ; THD <0.5%)
Gain range: -42 to +9dB
PAD attenuation: 15dB
Frequency response: (-3dB) 5Hz to 50 kHz
Low cut: (-3dB) 100 Hz (Shelving, 2nd order)
Warm: 2 kHz (Shelving, 1st order)
Low EQ: 460 Hz (Shelving) -20dB / +15dB
Parametric Mid EQ: 250 Hz – 3 kHz -15dB / +15dB
High EQ: 1.2 kHz (Shelving) -12dB / +12dB
Distortion (THD+N; @1kHz)
-30dBu input level
0dBu output level:
0.11% (2nd harmonic)
0.05% (3rd harmonic)
0.012% (4th harmonic)
0.006% (5th harmonic)
Power consumption: 4W (78mA)
Size & Weight: 36x58x475mm ; 0,5 kg
Blockdiagram

A CLASS-A unit that can receive signals from various sources (mostly audio devices generating a 0 dBV line signal) including effects units, CD players, tape or digital recorders, preamps and electronic instruments such as keyboards or MIDI devices.

Input section: The unit has two (left and right) fully balanced input connectors, which use space-saving stereo phone plugs. Connecting an unbalanced music signal, e.g. from a keyboard, via a simple guitar jack, is also possible. An unbalanced signal from a HiFi device such as a CD player can also be connected using two RCA connecters.

Although the stereo line input unit is intended for nominal line level signals, the input amp’s sensitivity can be adjusted, from -12 dB to +25 dB, using the GAIN knobs. Left and right channels can be separately adjusted. Depressing the UNITY button sets the gain to 1, allowing the signal to pass (without amplification or attenuation) independently from the Gain knob setting.

LOW and HIGH Filters: Line signals don’t usually need strong shaping, but some small correction of higher and lower frequencies can be useful. Both channels are affected simultaneously.
The CHANNEL ON button connects or disconnects the output routing for all outputs (AUX 1, AUX 2, AUX 3 and L/R), except the PFL routing. Similar to the MUTE button on other mixers, its functionality is however reversed: When the CHANNEL ON button is depressed, all outputs are connected. Also, whereas a MUTE normally only disconnects the L/R routing (the channel’s fader), this unit’s CHANNEL ON button affects all outputs.
The AUX SENDS include three knobs for the left level control of each send (AUX 1, AUX 2, AUX 3) and three knobs for the right level control. Each single AUX send can therefore be controlled independently. Every AUX send can also “read” the signal pre or post fade, through the use of switch buttons. If a button is not depressed (orange light), the signal arrives “post fade”, i.e. while the relevant auxiliary level is controlled by its level knob, the final outcome is also influenced by the channel fader’s position. If a button is depressed (blue light), the signal arrives “pre fade” and is sent to the AUX master without being affected by the channel fader’s position or movement. Note: To benefit from all the AUX sends (and other additional options), a MASTER AUX unit is required as well as the MASTER L/R unit. The MASTER L/R unit only receives AUX 1 and is intended for a basic configuration, e.g. when only one auxiliary send is needed to operate a reverb device and no stage monitors are being used. The MASTER AUX unit also offers a CLASS-A headphone output, talkback function and Room output to control the studio monitors.
MONO and PFL: Depressing the MONO button sets the unit’s stereo configuration to mono; i.e. the two L and R channels are mixed together. Useful when listening to a stereo program reproduced in mono, in order to evaluate its “mono compatibility”. Depressing the mono switch connects the single signal to both the L and R faders so that the music appears on both channels (depending on the setting of the L and R faders). When used on a single mono BUS, the PFL sends the L and R from the stereo input unit as a mono signal to the phones, or PFL output on the AUX master unit. As well as being a traditional PFL (pre fade listen), it also serves as a fourth AUX send (without the possibility to set any level). Signals from any channels with an activated PFL (red light) will be mixed in the MASTER AUX unit and sent to the PFL output, controlled by the PFL fader on the master AUX unit. Note: The PFL section still runs if the CHANNEL ON button is deactivated (white light).
L / R FADER section. In most cases, the signal going through here will be mixed in the L/R Master before appearing on the main L/R outputs that drive the recording device or the front-of-house PA speakers. Operating the L/R fader section is the same as on other mixing consoles. The PAN pot enables signal to be sent to the Left or Right channel by turning it in the appropriate direction. At the pot’s mid position, the signal flows to both channels at maximum level.

Input Impedance 20 kohm (UNBALANCED)
40 kohm (BALANCED)
Maximum input level: +28dBu (THD <0.5%)
Gain range: -12 dB to +25dB
Frequency response: (-3dB) 10Hz to 45 kHz
Low EQ: 500 Hz (Shelving) -13dB / +13dB
Hi EQ: 1.2 kHz (Shelving) -13dB / +14dB
Distortion at unity gain (THD+N; @1kHz)
-30dBu input level
0dBu output level:
0.10% (2nd harmonic)
0.06% (3rd harmonic)
0.022% (4th harmonic)
0.011% (5th harmonic)
Power consumption: 5W (105mA)
Size & Weight: 36x58x475mm ; 0,5 kg
Blockdiagram

The Multiple In is a CLASS-A input unit that can receive 4 line signals (or two stereo lines), as opposed to just the 2 lines that can be handled by the Stereo In unit. It does however include fewer features (no gain, filters or AUX routing), having been principally designed to enable simple routing of line signals to the L/R Master - which, in many cases will prove sufficient.

The Multiple In is mainly intended for use with audio devices that generate a line signal (0 dBV) from their output(s). This makes it particularly useful for sub group routing: Its inputs can accommodate effect units, CD players, tape or digital recorders, preamps of any kind and electronic instruments such as keyboards and Midi devices.

A number of Multiple In units combined with one L/R Master unit will create a summing amp of outstanding quality, which is both modular and money saving. For example, four Multiple In units will configure into a 16-channel summing amp

Input Impedance 41.4 kohm (BALANCED)
Maximum input level: +20dBu (THD <0.5%)
Gain range: -61 dBu to +6dBu
Frequency response: (-3dB)  
Equivalent input noise (EIN) 111,7dB (Gain @11.7dBu)
Distortion (THD+N, @1KHz) - 30dBu input level, 0dBu output level 0.15%; 0.12% 2nd harmonic; 0.06% 3rd harmonic; 0.04% 4th harmonic; 0.01% 5th harmonic
Power consumption: 80mA
Size & Weight: 36x58x475mm ; 0,5 kg
Blockdiagram