9
UL TRACOUSTIC ACX1000
+Please note that with all three EQ controls set fully to the left (instrument channel), the resulting
signal will be very low-volume.
10
The FEEDBACK 1 control adjusts a notch filter that allows you to suppress feedback frequencies or
other forms of interference. The frequency range is from 65 Hz through 400 Hz. To detect and suppress
interference frequencies, please turn the FEEDBACK 1 control slowly.
11
The FEEDBACK 2 control determines the frequency of a second notch filter, ranging from 150 Hz
through 900 Hz.
12
Use the FX RETURN control to determine the intensity of the effect selected on the effects module
(instrument channel).
13
The MIC jack is the balanced XLR microphone input of the microphone/line channel.
14
The balanced LINE/INST. jack of the microphone/line channel can be used for line-level signals, e.g.
keyboards, samplers etc.
15
The +48 V switch activates the phantom power supply for the XLR microphone input, providing the
operating voltage required for condenser microphones.
16
Use the GAIN control to determine the volume level of the microphone/line channel.
17
When the input signal overdrives the microphone/line channel, the CLIP LED signals this condition.
Reduce the input gain with the GAIN control, until the CLIP LED just stops lighting up. Occasional
flashing of the CLIP LED, caused by signal peaks, is harmless though, because the microphone/line
channel, too, has sufficient headroom.
18
The BASS control in the EQ section allows you to boost/cut the bass frequencies on the microphone/
line channel.
19
With the MID control you can boost/cut the midrange frequencies on the microphone/line channel.
20
Finally, the TREBLE control governs the microphone/line channel’s high frequency gain.
21
With the ENHANCER control you can add treble frequencies to the microphone/line signal, thus improving
the audio signal’s power and transparency.
22
The FEEDBACK 1 control adjusts a notch filter that allows you to suppress feedback frequencies or
other forms of interference. The frequency range is from 650 Hz through 4 kHz. To detect and suppress
interference frequencies, please turn the FEEDBACK 1 control slowly.
23
The FEEDBACK 2 control determines the frequency of a second notch filter, ranging from 1.5 kHz
through 9.5 kHz.
24
Use the FX RETURN control to determine the intensity of the effect selected on the effects module
(microphone/line channel).
25
The WARMTH control adjusts the ULTRACOUSTIC’s tube emulator circuit. The more you turn this
control to the right, the more upper harmonics are added to the signals on the instrument or microphone/
line channels, which results in a sound of unobtrusive brilliance with improved power and transparency.
26
Use this CONTROL INDICATOR to assess the amount of upper harmonics added with the WARMTH
control.
+To achieve the maximum tube emulation effect, both channels should be set to correct levels.
The CLIP LED should be flashing with signal peaks only. Make sure it never lights up all the
time.
27
The PHASE switch reverses the phase of the mix signal by 180°. Use this switch to eliminate feedback
problems.
28
The MASTER control determines the overall volume level of your ULTRACOUSTIC.
29
The ULTRACOUSTIC features a limiter circuit in the master section. The LIM LED lights up as soon as
the limiter is on.
1. INTRODUCTION