The NTMB+ GFL is a preamp voiced for fretless bass that incorporates fully independed Bass, Mid and Treble controls with very low noise and a wide boost/cut range.
It is a single module for ease of installation and includes a gain trim.
The sound is very clear and transparent. Distortion is well below 0.001%. This preamp can be used with either 1 - 9 volt battery ( 9 volt operation) or 2 - 9 volt batteries (18 volt operation) which yields 6 dB extra headroom.
In 9 volt operation the NTMB+ uses approximately 750 microamperes of current from 1 - 9 volt battery. This means 1 month of continuous duty or more than 6 months of average usage.
In 18 volt operation the NTMB+ uses approximately 1000 microamperes of current from 2 - 9 volt batteries. This means more than 3 weeks of continuous duty or more than 4 months of average usage.
Mid frequency options.: 250, 500, 800Hz
See wiring diagram below