C Class Signal Processors TUBE MICROPHONE/INSTRUMENT PREAMPLIFIER WITH DIGITAL OUTPUT
Safety Instructions
Table of Contents Introduction C valve Features Controls and Functions Front Panel Layout Rear Panel Layout Operating the C valve Setting Up the C valve Setting a Good Level Using The C valve For Getting A Sound Using the Low Cut Filter Using the Tube Process Using the Enhancer Using C valve With An External Signal Processor Using the Digital Output Using the Digital Link Jack System Set-ups Stacking and Tilting the C valve C valve Connections C•Class Dual Rack Adapter (optional) Block Diagram Specificatio
Congratulations! You just purchased one of the most useful audio tools for digital audio recording, C valve from Samson Audio. The C valve is a high quality microphone/instrument tube pre-amplifier offering a tremendous amount of transparent gain with a pristine audio path that terminates in both balanced analog and S/PDIF digital outputs.
C valve Features The Samson C valve microphone and instrument pre-amp utilizes the latest technology in circuit design. Here are some of its main features: • A high quality microphone or instrument pre-amplifier using discrete transistor and tube gain cells. • On board Limiter for leveling the output is useful in recording and live sound applications. • The total amount of harmonic overtones or “warmth” can be controlled using the Saturation control.
C valve Layout 1 INPUT GAIN – Rotary control used to adjust the input level. 2 LOW FREQUENCY – This rotary control is used to set the EQ cut off point for the Low Cut filter. 3 INPUT METER – Six segment LED VU meter displays the input level after being affected by the Gain control. 4 SATURATION – Rotary control used to adjust the total amount of harmonic overtones generated by the tube circuit.
C valve Layout Rear Panel Layout A AC INLET – Connect the included AC1800 power supply here. F SEND (INSERT) - 1/4-inch phone jack for carrying the send signal for the external processing loop. B 24 BIT 48 / 96 (DIGITAL OUT)- 24-bit S/PDIF Digital Output on an RCA connector. G INSTRUMENT IN - 1/4-inch phone input jack for connecting signals from instruments or line level devices.
Operating The C valve Setting up the C valve Setting up your C Valve tube pre-amp is a simple procedure, which takes only a few minutes: 1. Remove all packing materials (save them in case of need for future service) and decide where the pre-amp is to be physically placed. To avoid potential overheating problems, be sure that there is good ventilation around the entire unit. 2. Plug the provided AC power adapter in the rear AC inlet, but don’t plug the power pack into a wall outlet just yet. 3.
Operating The C valve Setting Up the C valve (continued) 6. Plug the C valve power pack into a wall outlet and switch the unit on by pressing the power switch. 7. If you are using an instrument with your C valve, press the MIC/INST switch in to set the C valve’s input to accept instrument levels. The LED will illuminate. If you are using a microphone skip this step and go on to the next step. 8. The C valve features on board 48-volt phantom power supply for connecting condenser microphones.
Operating The C valve Setting a Good Level One of the most important fundamentals of good audio engineering is setting proper levels. Even on a small typical mixer, or basic multi-track recorder, there are several controls that affect the level of a signal as it makes it’s way from your sound source to your speakers and then, ultimately, the level of your headphone or monitor system.
Operating The C valve 4 MIC/INST - Select switch The MIC/INST switch is used to set the operating level of the C valve’s input. When using a microphone, set the switch to the “MIC” position, which is selected when the switch is in the out position and the green LED is off. When you press the MIC/INST switch in, the green LED will illuminate indicating that the C valve is ready to accept a signal from an instrument like a guitar or bass guitar.
Operating The C valve Using the Low Cut Filter ( continued) LOW FREQUENCY You can set the exact frequency to start attenuating the low-end using the LOW FREQUENCY control knob. Be sure that the LOW CUT filter switch is engaged as described in the previous section. The variable LOW FREQUENCY rotary knob allows you to set the low-cut filter to operate at any frequency from 18 to 300Hz. Using the Tube Process The C valve features a 12AX7 vacuum tube for adding extra harmonic content to the signal.
Using C valve With An External Signal Processor To further control your signal, the C valve features an insertion point, or “effects loop”, on two 1/4-inch phone jacks, INSERT SEND and RETURN. An insertion point is a patch-point that interrupts the signal, allowing you to bring that signal outside to be processed by another device.
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C valve System Set-Ups Using C Valve in a Live PA System 14
C valve System Set-Ups 15
Stacking and Tilting the C valve Stacking the C valve You can stack one C valve, or any other Samson C Class units, on top of each other by simply lining up the bumpers. Important Note: When stacking the C valve, be sure that only the bottom unit has the tilting feet installed. Installing the Tilting Feet You can install the tilting rubber feet included with your C valve so that you can set the unit at a comfortable operating angle on a workstation or desktop.
C valve Connections CONNECTING THE C valve The are several ways to interface the C valve to support a variety of applications. The C valve features servobalanced inputs and outputs, so connecting balanced and unbalanced signals is possible without any signal loss. The C valve can be used on a single instrument by connecting to a channel’s insert points, or on an entire mix "in-line" between a mixer’s outputs and a power amp or equalizer.
C•Class Dual Rack Adapter (optional) The C Class Dual Rack Adapter is available as an accessory from an authorized Samson dealer. 1. 2. 3. 4. 5. Disconnect any cables, that may be connected, from the C•Class unit to be mounted, i.e., the power supply cable, audio cables, headphones. Align the holes in the C•Rack with the holes on the bottom of of the C•Class unit to be mounted. Use the supplied phillips head M4 machine screws to fix the unit to the rack as shown below.
C valve Block Diagram 19
Specifications System Specifications Frequency Response Dynamic range THD Crosstalk Detector 20Hz to 20kHz + - 0.5 dB 95 dBu, un-weighted, 22 Hz to 22 kHz 0.008 % typ. @ +4 dBu, 1 kHz 90dB 22 Hz to 22 kHz RMS Inst/Line In Connectors Impedance Max. Input Level 1/4"TRS jack 1 meg Ohm balanced +21 dBu, balanced and unbalanced Mic Input Connectors Impedance Max. Input Level CMRR XLR 2.5k Ohm balanced +21 dBu, balanced and unbalanced Typ. 40dB, >55dB @ 1kHz Analog Output Connectors Impedance Max.
Samson Technologies Corp. 575 Underhill Blvd. P.O. Box 9031 Syosset, NY 11791-9031 Phone: 1-800-3-SAMSON (1-800-372-6766) Fax: 516-364-3888 www.samsontech.
