Demeter Amplification VTBP-201S User Manual

6990 Kingsbury Road | Templeton, CA 93465 | 805-461-4100 | http://www.demeteramps.com/

VTBP-201S Tube Bass Preamplier User’s Guide

The classic VTBP-201 by James Demeter is now reborn in this new single space rack chassis. All of

the sound and controls of the classic have been retained and some new features have been added. The
VTBP-201S bass preamplier continues the sonic excellence of its predecessor. It features a high volt­age (270V fully regulated), all tube design providing all of the tube preamplier gain and output drivers,
classic passive tone controls, and a balanced microphone level Jensen transformer output for recording
or house PA. Two unbalanced line level outputs for amplier connections and a mute switch. As with all
Demeter equipment, it is meticulously hand wired using the nest components and assembled in the
U.S.A.

CONTROLS AND FEATURES

INPUTS
Passive: For passive basses or basses with lower output.
Active: Provided for basses with internal preampliers or basses with a very high output. If both inputs
are used, there is a circuit that mixes the inputs.

TUBE PREAMPLIFIER
Bright Switch: this boosts the high frequency at 6 dB per octave from 1 kHz. The total gain of the bright
switch is dependent on the volume control setting (i.e. the lower the volume the greater the eect of the
bright switch).
Volume: this controls the output level of all outputs except the eects loop and tuner.
Treble: a passive 6 dB per octave, shelving and high frequency control. Boost or cut of 10dB. This con­trol eects the 4 k to 20 k range.
Middle: a passive 6 dB per octave peaking mid frequency control. Boost or cut of 10 dB. This control is
centered at 600 Hz.
Bass: a passive 6 dB per octave, shelving, low frequency control. Boost or cut of 10 dB. This control ef­fects the 120 Hz to 10 Hz range or the 240 to 20 Hz range depending on the EQ switch’s setting.
Presence: an active 6 dB per octave, shelving upper-mid to high frequency control. Boost in the 2 to 20
k range. The at setting for this control is the knob turned all the way to the left.
Bass EQ Switch: selects between the peak frequencies of 60 Hz and 120 Hz for the bass control.
Presence Frequency Switch: selects between the peak frequency of 2 kHz and 4 kHz for the presence

control.

EFFECTS LOOP

Eects Loop Switch: this switch engages the eects loop section of the preamplier activating the back
and the controls in front. With nothing inserted in this jack, the switch will kill the signal.
Send Control: controls the level leaving the send jack of the preamplier (the input jack of your eect).
Return Control: controls the level returning to the preamplier from your eects unit into the bass pre­amplier.
Mute Switch: mutes all outputs except the at setting on the Jensen balanced output and tuner output.

6990 Kingsbury Road | Templeton, CA 93465 | 805-461-4100 | http://www.demeteramps.com/

VTBP-201S Tube Bass Preamplier User’s Guide

REAR PANEL CONTROLS

Ground Lift Switch: this switch lifts the chassis ground from one pin of the XLR connector. This is used
when hum and noise are present in the connection.
EQ/Flat Switch: switches between a at tube buered output and the main output of the preamplier

outputs.

REAR PANEL OUTPUTS
Three Pin XLR: this output is fully balanced. It is the output used for recording and for connecting to PA
consoles. It is aected by the switches on either side of it.
Unbalance Output: this output is designed for connection to power ampliers or other devices.

REAR PANEL EFFECTS LOOP

Eects Loop: this output connects to the input of your eects unit (compressor, delay etc.). The level

controls for output are on the front panel.

Eects Return: this input is connected to the output of your eects unit. The level controls for this input

are on the front panel.

Tuner Output: this output is designed for connection to your tuner. It is not aected by the mute switch
or volume control of the preamplier.