Demeter Amplification HBP-1 H series User manual

HBP-1 H Series Bass Preamplier User’s Guide
The H Series Bass Preamplier by James Demeter uses the same all tube front end found in his clas-
sic VTBP-201S Bass Preamplier and combines it with the revolutionary H Series circuitry found in his
professional audio H Series line. This preamplier provides the best of both the tube and solid state
world. It features high voltage (250V) tube front end (providing all of the preamplier gain and passive
tone controls), a two band solid state fully Parametric Equalizer that is tuned for bass, a fully adjustable
active eects loop with controls up front, a tuner output, a full balanced output with switchable micro-
phone or line level, both a balanced TRS line level output and an unbalanced line level output 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: is for passive basses or basses with lower output.
Active: is provided for basses with internal preampliers or basses with very high output.
TUBE PREAMPLIFIER
Volume: controls the output level for all outputs except the eects loop and tuner.
Treble: a passive 6 dB per octave shelving high frequency control. Boosts or cuts 10 dB. This control af-
fects the 4 k to 20 k range.
Middle: a passive 6 dB per octave peaking mid frequency control. Boosts or cuts 10 dB. This control is
centered at 1 kHz.
Bass: a passive 6 dB per octave shelving low frequency control. Boosts or cuts 10 dB. This control af-
fects the 120 Hz to 10 Hz range.
Presence: an active 6 dB per octave shelving upper mid to high frequency control. Boosts in the 1 k to
20 k range. The at setting for this control is the knob turned all the way to to the left.
PARAMETRIC EQ
EQ Switch: switches in or out of circuit the parametric EQ.
Boost/Cut: controls the boost and cut of the parametric EQ plus or minus 12 dB.
Frequency Controls: continuously variable frequency selection for each bandwidth (low frequency or
mid frequency). The number shows the center frequency.
Q or Width Control: controls how wide or narrow the aected frequency are. The most narrow setting is
one half octave and the widest is four octaves around the center frequency.
6990 Kingsbury Road | Templeton, CA 93465 | 805-461-4100 | http://www.demeteramps.com/

HBP-1 H Series Bass Preamplier User’s Guide
EFFECTS LOOP
Eects Loop Switch: this switch engages the the eects loop section of the preamplier activating the
jacks in the back and the controls in front. With nothing inserted in the jacks this switch will kill the
signal.
Send Control: controls level leaving the send jacks of the preamplier (the input jacks of your eect).
Return Control: controls the level returning to the preamplier from your eects unit into the bass pre-
amplier.
Mute Switch: mutes all outputs except the tuner output.
REAR PANEL CONTROLS
Ground Lift Switch: This switch lifts the chassis ground from pin one of the XLR connector. This is used
when hum and noise are present in this connection.
Level Switch: This switch changes the output level of the XLR from line level (+4 dB) to microphone
(level -20 dB). The microphone level is used to input recording consoles microphone preampliers. The
line level is for line level and power amp connections.
REAR PANEL OUTPUTS
Three Pin XLR: This output is a fully balanced. It is the output used for recording and for connecting to
power ampliers with XLR connections. It is aected by the switches on either side of it. Warning: do
not connect this to mixers with 48+ volt phantom power: it will damage the preamplier.
Balanced TRS Output: This output is a 1/4” TRS connector used for TRS input power ampliers or any
other TRS input device. This output has 6 dB more output than the unbalanced output in the balanced
mode. If used in the unbalanced (ring grounded) mode this output is 3 dB louder than the unbalanced
out.
Unbalance output: this output is designed for connection to power ampliers or other devices with un-
balanced inputs. It has 3 dB to 6 dB less output than the balanced output. Note: if for any reason there
is damage done to the balanced output system (i.e. phantom power) this output will still work.
REAR PANEL EFFECTS LOOP
Send: this output connects to the input of your eects unit (compressor, delay etc.). The level controls
for this output are on the front panel.
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 the volume control of the preamplier.
6990 Kingsbury Road | Templeton, CA 93465 | 805-461-4100 | http://www.demeteramps.com/