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TubePRE
Single-Channel Tube Mic-Preamplifier w/ VU Meter
User's Manual
VERSION 1.0
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Presonus Limited Warranty Presonus Audio Electronics Inc. warrants this product to be free of defects in material and workmanship for a period of one year from the date of original retail purchase. This warranty is enforceable only by the original retail purchaser. To be protected by this warranty, the purchaser must complete and return the enclosed warranty card within 14 days of purchase. During the warranty period Presonus shall, at its sole and absolute option, either repair or replace, free
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Limited Warranty Outside of The U.S. Presonus Audio Electronics products are warranted only in the country where purchased, through the authorized Presonus distributor in that country, against defects in material and workmanship. The specific period of this limited warranty shall be that which is described to the original retail purchaser by the authorized Presonus dealer or distributor at the time of purchase. Presonus does not, however, warrant its products against any and all defects: 1) aris
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Table of Contents 1.1 Introduction........................................................................1 1.2 Features.........................................................................................2 2.1 Controls & Connections .......................................................4 2.2 Front Panel.....................................................................................4 2.3 Preamplifier Section .........................................................................4 2.4
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1.1 INTRODUCTION Thank you for purchasing the Presonus TubePRE Single-Channel Microphone/Instrument Tube Preamplifier. This pre-amp was designed using state of the art components to deliver crystal clear audio for an infinite period of time. We feel that we have created a reliable, versatile and affordable piece of audio equipment. It is designed to meet a multitude of professional audio applications. If you have any questions or comments in regards to this or any other piece of Presonus equipme
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1.2 Features The following is a summary of your TubePRE's features: Dual-Servo Gain Stage Your TubePRE contains a dual-servo gain stage (no capacitors). This provides ultra-low noise performance and wide dynamic control. This gives the TubePRE the ability to boost the desirable signal without increasing unwanted background noise. Phantom Power When the phantom power switch is engaged, power is supplied at a constant rate. This assures optimum performance of your condenser microphone and that the
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80Hz Rumble Filter A rumble filter is available to eliminate low frequency noise. This lets you greatly reduce background noise from things such as air conditioners or wind noise with the flick of a switch without affecting the desired frequencies. Mic/Instrument Input The TubePRE has a separate XLR and 1/4” connector on the back of the chassis for signal input from microphones (XLR) or instruments (1/4”). Drive The TubePRE provides a Drive potentiometer for controlling the amount of signal rout
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2.1 CONTROLS & CONNECTIONS 2.2 Front Panel The TubePRE front panel has the following features: Phantom Power Switch (+48v) Phase Reverse Switch Drive Control (0 to 20dB) -20db Pad Gain Control (0 to 40dB) 80Hz filter Backlit VU meter 2.3 Preamplifier Section Phantom power is available for the input of the TubePRE. The 48 volts are supplied through the XLR connector for condenser mics and any other devices requiring continuous power (through the XLR input). 4
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XLR wiring for phantom power PIN 1 GND PIN 2 +48v PIN 3 +48v Phase Reverse Switch Allows the user to invert the polarity of the XLR connector by switching pins two and three. The inversion of the pins of the XLR connector may be necessary to alter the audio phase of two like microphones to compensate for phase cancellation. It may be required that the wiring of a cable’s XLR connector be switched to successfully utilize phantom power. -20dB Pad Provides -20 decibels of attenuation with the push
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infinitely richer and sweeter. An overdriven signal can be achieved by significantly raising the level of the drive control. This overdriven tube effect is extremely useful in providing distorted guitar and for creating that authentic “blues harp” vibe (harmonica). The possibilities of the drive control are limited only to your application and your imagination. Gain This control governs the amount of boost to the signal being processed by the preamplifier. Dynamic mics and instruments without pr
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1/4” phone plug wiring input and output TIP High (+) SLEEVE GND (-) The output 1/4” phone plug is unbalanced 7
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3.1 OPERATION 3.2 Dynamic Microphones Lower output levels characterize dynamic microphones, so more gain is needed to achieve sufficient operating levels. Occasionally it is necessary to add the -20dB pad to the microphone to avoid distortion (e.g. when recording percussion). Do not use phantom power when using dynamic microphones. 3.3 Phantom Powered Microphones Phantom powered microphones such as condenser and some ribbon microphones require external power to preamplify the microphone. These m
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how hard the tube is driven when in use. Signs of wear may be exhibited by poor performance or by the tube becoming “microphonic”. Periodic replacement of the vacuum tube is recommended. The time between the suggested replacements varies greatly with use. If you notice deterioration in sound quality then it’s time to change the tube. Replacing the tube in the TubePRE 1. Unplug the unit. Proceed with caution, as the tube could be hot. Remove the two screws from the top and the two screws from the
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With a compressor/EQ/dynamics processor When running the Tube Pre in conjunction with other processors it is recommended that the TubePRE be the first unit in the chain. The other units should be connected to the output (either XLR or 1/4”) of the TubePRE. Most compressors require that the signal be preamplified before they are connected. This simply means that the signal is loud enough for the compressor to process it. In most cases (and there are exceptions) if you were to plug a microphone/gu
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If the voltage on the back of my TubePRE does not match the voltage listed on the power supply what do I do? The voltage on the TubePRE’s external power supply may change. If the power supply came factory sealed with the unit, then it is the right power supply. If the power supply did not come with the unit it is recommended that it not be used. If your power supply is damaged or missing, please consult your salesperson or call Presonus. Can I use a higher/lower/alternate voltage power supply th
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Can I plug my keyboard/CD player/etc into the TubePRE? It is not recommended that any LINE LEVEL items be plugged into the TubePRE. This scenario will not cause damage to the unit. However, it may cause the signal to distort or sound unpleasant. The reason is that the signal being fed into the unit is too loud for the TubePRE. This may cause the unit to distort (In some cases this may be the desired effect). Whenever I turn up the tube drive all the way my signal sounds distorted. Why is this? T
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9.1 TECHNICIAL SPECIFICATIONS Preamp Bandwidth..................................................... 10Hz to 50kHz Number of Channels .................................................................One Performance THD + Noise (Unweighted) ......................... 0.05% @ 0dB Tube Drive ................................................................. 10% @ 20dB Tube Drive Noise Floor ......................................................................... -94dBu Signal to Noise................
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Metering VU Meter.............................................................. -20dBu to +3dBu Clip LED ............................................................................ +20dBu Power Supply Type..................................................... Linear/External Transformer Input .....................................................................16 VAC/1000mA Power ............................................................................ 16 WATTS Physical Weight................
