PulpLogic Entry Point User manual

Entry Point
User Guide
May 2012
Rev. B

Introduction:
The Eurorack platfor is rich in sound shaping tools that can be used to create new and innovative effects for
stringed instru ents. The Entry Point allows you to take advantage of this sonic landscape by acting as a bridge
between your electric or bass guitar and Eurorack odular synthesizer. Instead of buying a single effect pedal
to achieve a desired sound, now you can patch ultiple odules to build your own unique effects with the
individual characteristics you desire. The Entry Point perfor s three pri ary functions when connecting your
instru ent to a Eurorack syste . First, it acts as a low noise prea plifier to bring your instru ent up to
Eurorack signal levels. Second, it generates an envelope voltage that follows your playing dyna ics for use as a
control voltage. Third, it extracts the funda ental frequency of the note played and outputs it as a square
wave signal for processing in the odular.
Preamplifier:
The Entry Point's prea plifier is designed to a plify usical instru ents up to Eurorack signal levels. When
connecting traditional passive instru ents or other low signal level devices, the ACTIVE/PASSIVE switch should
be set to the passive position. When connecting active instru ents or other devices that output line level
signals the switch should be set to the active position. The switch position affects both the envelope follower
and the square wave generator and should be set prior to aking any other adjust ents. The GAIN control
knob sets the a plitude of the signal co ing out of the the SIG jack. The a plitude of the SIG output is
displayed on the LED signal strength eter.
Envelope Follower:
The envelope follower generates a control voltage that correlates with the dyna ics of your playing. An
envelope is output when the a plitude of the input signal is greater than the threshold set by the THRESH
knob. Exceeding the set threshold is displayed by illu ination of the blue threshold LED. The RATIO control
sets the a ount gain that is applied to the control signal that has exceeded threshold. A wide range of
envelope shapes can be achieved by the anipulation of these controls. For an envelope shape that follows the
overall dyna ics of the input signal, the THRESH control should be set to the ini u threshold (full
clockwise) and the RATIO control should be adjusted to set the axi u envelope size. To create an envelope
that responds to the ost dyna ic parts of the input signal, raise the THRESH control so the threshold LED
illu inates only on the loudest parts of the input signal. Then adjust the RATIO control for the desired
envelope a plitude. The envelope follower control voltage is available as both a positive control ENV + and
negative control ENV - . The range on the ENV + output is 0 to 5V and the range on the ENV – is 5V to 0 or 0 to
-5V as set by H101.
ENV – : 5V down to 0V (default configuration) ENV – : 0V down to -5V (user option)
Square Wave Generator:
The square wave generator extracts the funda ental frequency of the single note being played and outputs it
as a ±5V square wave on the SQR jack. The TRACK control knob allows for adjust ents to be ade to the bias
of the extraction circuit. When this control is in the counterclockwise position the circuit is very sensitive and
an output can be triggered with an extre ely light touch. As the control is rotated clockwise, the sensitivity is
reduced resulting in ore precise tracking; however the sustain of a note will be shortened. The quality of the
tracking is largely dependent on a nu ber of factors such as the instru ent configuration, setup, and playing
technique. Playing with a soft touch and using only the neck pickup will generally offer good results. Poor
tracking will result in an output that ju ps between the funda ental and the second har onic (octave up). At
ti es this ight be just the thing you're looking for, so have at it.

1. Instrument Input
1/4” phone jack input for connection to both passive and
active instru ents.
2. Active Passive Selector Switch
Selects the a ount of gain required to bring your instru ent's
output up to a line level signal. For passive instru ents with
standard high i pedance pickups the switch should be set to
PASSIVE for best results. When using instru ents with on-
board active electronics or when feeding the Entry Point fro
the output of an external prea plifier, the switch should be
set in active ode. So e instru ents with active pickups
(like EMG) produce relatively low output signals and ay
work best in passive ode. Since every instru ent is
different experi entation is encouraged.
3. Output Level Control
Sets the output level for the 3.5 SIG jack. The required
output level is dependent on the next odule in the
processing chain. Experi ent with driving filters and other
odules with different a ounts of gain to broaden your
sound palette. Once you find the sweet-spot for a particular
odule, note the LED etering level for repeatability.
4. Output Level Metering
The LED output etering provides a visual feedback for the proper level settings. The eter is particularly
valuable when playing live as it allows you to quickly setup your syste based on predeter ined levels.
5. Fundamental Tracking
The TRACK control is used to set the bias for the funda ental extractor. In the counterclockwise position the
extractor is at it's ost sensitive setting. In this position the extractor ay be unreliable when tracking low
frequency notes and open strings. This will be evident by the note ju ping between the funda ental and an
octave above the funda ental. As the control is rotated clockwise, tracking will i prove but the sustain will
be shortened.
6. Envelope Threshold
The envelope threshold control THRESH is used to set the ini u signal necessary before an envelope is
created. Once the input signal crosses the set threshold level, an envelope will be present on the ENV+ and
ENV- jacks. The a plitude of the envelope will be the a ount of signal over threshold ultiplied by the ratio.
The blue led illu inates when threshold has been exceeded.
7. Envelope Ratio
The ratio control sets the gain for the envelope follower. Large envelope ratios allow for the generation of
envelopes that span the full control range on input signals that just barley exceed the threshold.
8. Output Group
3.5 output jacks for interfacing with Eurorack odules. The SIG jack delivers a clean Eurorack level
representation of your instru ent's output. The SQR jack is the square wave output of the funda ental
extractor. The ENV+ and ENV- jacks output the rising and falling envelope control voltages. The rising envelope
is 0V to 5V and the falling envelope is 5V to 0V or 0V to -5V.
9. Balanced Output
This output provides a line level balanced copy of the input signal. The jack is TRS balanced with the tip
connected to the in phase signal and the ring to the -180° signal. It is safe to use a standard TS instru ent
cable if an un-balanced output is needed.

Specifications:
Form Factor - Panel Size: 10 HP Eurorack panel
Depth (Back of panel to Max): 35 (1.38”)
Power - Connector: Eurorack 16 pin keyed header
+5V: Not Used
+12V: 55 A Max Consu ption
-12V: 55 A Max Consu ption
Max Operating Voltage: ±15V
Electrical - Instrument Input:
Connector: 1/4” TS Phone Jack (Unbalanced)
Input I pedance: 1 Meg Ω
Direct Output:
Connector: 1/4” TRS Phone Jack (Balanced Line Level)
Output I pedance: 470 Ω
THD + N (20Hz – 20kHz): < 0.002%
SNR (A-weighted): 112dB
Gain Passive +22dB Unbalanced
+28dB Balanced
Gain Active +6 dB Unbalanced
+12dB Balanced
Max Output Before Clipping: ±12V Rails - ±10Vpk (+19 dB )
±15V Rails - ±13Vpk (+22 dB )
Signal Output “SIG”:
Connector: 3.5 TS Jack (unbalanced)
Output I pedance: 470 Ω
THD + N (20Hz – 20kHz): < 0.002%
SNR (A-weighted): 110dB
Max Gain Passive +35dB
Max Gain Active +18dB
Max Output Before Clipping: ±12V Rails - ±10Vpk (+19 dB )
±15V Rails - ±13Vpk (+22 dB )
Square Wave Output “SQR”:
Connector: 3.5 TS Jack (unbalanced)
Output I pedance: 470 Ω Output I pedance
Output Signal: ±4.8Vpk (dc coupled)
ositive Envelope “ENV +”:
Connector: 3.5 TS Jack (unbalanced)
Output I pedance: 470 Ω Output I pedance
Envelope Detector: True RMS (THAT 2252)
Output Signal: 0V up-to 5.4V
Negative Envelope “ENV -”:
Connector: 3.5 TS Jack (unbalanced)
Output I pedance: 470 Ω Output I pedance
Output Signal: 5.4V down-to 0V or 0V down-to -5.4V (j p opt)