® GVT52-112 Guitar Amplifier OWNER’S MANUAL
IMPORTANT SAFETY INSTRUCTIONS 1. Read these instructions. 15. Do not overload wall outlets and extension cords as this can result in a risk of fire or electric shock. 2. Keep these instructions. 3. Heed all warnings. 4. Follow all instructions. 5. Do not use this apparatus near water. 6. Clean only with a dry cloth. 7. Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions. 8.
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
TABLE OF CONTENTS Important Safety Instructions..............................................2–3 Introduction...........................................................................4 Special Features....................................................................5 The Front Panel – Channel 1...................................................6 The Front Panel – Channel 2...................................................7 The Rear Panel..................................................................
Special Features • Dual Channel, All-Tube Circuit Path, Push-Pull, Class AB • Power Output: 50W Full Power / 25W Half Power • Preamp Tubes: 3 x 12AX7 / ECC83 / 7025 • Power Tubes: 2 x 6L6GC • Rectifier: Solid State • Channel 1: Voiced for low to moderate gain tones. Ideal for clean, crunchy rhythm and old school lead tones • Channel 2: Voiced for moderate to high gain tones.
The Front Panel – Channel 1 1 2 3 The gain, treble, middle, bass and volume knobs as seen above and mentioned below [#2 – #6] are for channel 1 only. See the next page for the channel 2 illustration and descriptions. 1. INPUT: Connect a guitar to this 1/4" input using a high-quality shielded instrument cable. 2. GAIN: This control adjusts the gain of the amplifier. 3. TREBLE: Use this to adjust the high frequency level of the amplifier.
The Front Panel – Channel 2 8 9 10 11 12 The gain, treble, middle, bass and volume knobs as seen above and mentioned below [#8 – #12] are for channel 2 only. See the previous page for the channel 1 illustration and descriptions. 8. GAIN: This control adjusts the gain of the amplifier. 9. TREBLE: Use this to adjust the high frequency level of the amplifier. This provides up to 12 dB of boost or 12 dB of cut at 5 kHz. The high frequency output is flat at the center position. 10.
The Rear Panel 18 19 20 21 22 18. AC POWER INPUT: The amplifier is equipped with a detachable power cable that plugs into the IEC Mains socket on the back of the amplifier. The AC power cord should only be plugged into a grounded power outlet that meets all applicable electrical codes and is compatible with the voltage, power, and frequency requirements stated on the rear panel of the amplifier. Do not attempt to defeat the safety ground connection.
The Rear Panel continued... 18 19 20 21 22 23 24 25 26 23. EFFECTS LOOP SEND: Use this 1/4" TS unbalanced output to send a line-level output to an external effects processor (for example). The output here is affected by all controls except the Volume [6, 12]. Use the Effects Loop Return jack [22] to feed the returned processed signals back into the amplifier. WARNING! Never turn on or use the amplifier without a load or speaker connected to the amplifier.
Important Information about Tubes: The Nature Of Tubes — Why (And When To) Replace Them: Tubes are made up of a number of fragile mechanical components that are vacuum-sealed in a glass envelope or bubble. The tube’s longevity is based on a number of factors which include how hard and often the amplifier is played, vibration from the speakers, road travel, repeated set up and tear down, etc. Any time you notice a change in the amplifier’s performance, check the tubes first.
Important Information About Tubes (continued): Changing the Tubes: To get to the power tubes, the rear screen must be removed and the tube retainer(s) must be moved out of the way. Qualified service persons may follow these steps to change the tubes: • Turn the amp off, unplug it and let it cool for at least 5 minutes. • Remove the screws which hold the perforated metal screen to the rear of the cabinet. • Set the perforated metal screen aside.
Important Information About Tubes (continued): Survival Tips for Tube Amplifiers: To prolong tube life, observe the following tips and recommendations: • Match the impedance of the speaker cabinet(s) to the amplifier. Improper impedance matching will contribute to early tube degradation and may cause premature tube failure. • Make sure the speaker(s) are properly connected prior to turning on the amplifier. • Allow sufficient time for the amplifier to properly cool down prior to moving it.
Guitar Amplifier MIDRANGE REVERB B+ ™ 1/2 12AX7A POWER 6L6GC 6L6GC 4Ω B+ FULL / STANDBY / HALF SWITCH VOLUME CH SELECT / BOOST FOOTSWITCH CH SELECT / BOOST FOOTSWITCH SPEAKER OUTPUTS MASTER FULL / STANDBY / HALF SWITCH 1/2 12AX7A POWER TREBLE TONE CONTROL CIRCUITRY VOLUME TREBLE REVERB SEND RETURN 6L6GC BASS 1/2 12AX7A EFFECTS LOOP / REVERB FOOTSWITCH 1/2 12AX7A 6L6GC 1/2 12AX7A TONE CONTROL CIRCUITRY TREBLE BASS TRUE BYPASS GAIN 1/2 12AX7A TONE CONTROL CIRCUITRY BASS TONE
TECHNICAL SPECIFICATIONS Preamp Tubes Power Amp Tubes Premium 3 x 12AX7 / ECC83 / 7025 Premium 2 x 6L6GC Output Power Rating 50 watts rms (“full” tetrode mode) / 25 watts rms (“half” triode mode) into 4, 8 or 16 Ω Maximum Gain - Channel 1 64 dB @ 1 kHz, volume max, tones centered, boost engaged, 16 Ω out Maximum Gain - Channel 2 100 dB @ 1 kHz, volume max, tones centered, boost engaged, 16 Ω out Tone Controls - Channel 1 Bass: +12 / –12 dB @ 80 Hz Middle:
Service Information If there is a problem with the GVT52-112 amplifier, please visit our website (www.ampeg.com) and click on Support for service information, or call Technical Support at 1-800-898-3211 Monday – Friday during normal business hours, Pacific Time, to receive assistance. GVT52-112 owners outside of the U.S., contact the local distributor for technical support and service. The GVT52-112 is covered with a durable fabric-backed vinyl material. Clean with a dry lint-free cloth.
® 211-25TVG reifilpmA ratiuG LAUNAM S’RENWO
