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Dear valued customers We would like to take a moment to express our sincerest gratitude for choosing our product. We are thrilled to have the opportunity to enhance your audio experience and provide you with high-quality sound. Before using your new amplifier, we kindly remind you to read the user manual carefully before use. The manual contains important information such as basic precautions and guidelines for proper usage.
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Introduction Thank you for purchasing this Audio-Technica product. Before using the product, read through this user manual to ensure that you will use the product correctly. Please keep this manual for future reference. • This product can only be used in the country in which it was sold. •...
Notes on use • Be sure to read the connected device’s user manual before use. • Do not subject the product to strong impact to avoid electric shock, malfunction or fire. • Do not store the product under direct sunlight, near heating devices or in a hot, humid or dusty place to avoid malfunction.
Package contents Before using this product, please make sure that all of the following items are included in the package. If some items are missing or damaged, contact your local Audio-Technica dealer. Amplifier main unit Vacuum tube (TA-300B) (replacement) x 4 Function explanation plate There are no indications on the switches or dials of the amplifier itself.
Part names and functions Front panel Power indicator When the power switch is turned ON, the light blinks for about 90 seconds and then turns on. While blinking, it is warming up. Power switch Input selector switch BAL1: Balanced 1 BAL2: Balanced 2 LINE: LINE 1 Output selector switch...
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Part names and functions Volume control dial Adjusts the volume of the headphone output and pre-output. Left/Right balance adjustment dial Adjusts the left/right volume balance. XLR4 balanced output jack Connect headphones. 6.3 mm headphone output jack Connect headphones.
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Part names and functions Rear panel Line pre-output terminal Connect to a power amplifier or similar device using an RCA audio cable. XLR balanced pre-output terminal Connect to a power amplifier or similar device using an XLR balanced cable. Line input terminal Connect to a CD player or other device using an RCA audio cable.
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Part names and functions Fuse holder Use the specified fuse. Supply voltage Fuse (Rating/Model Name/Manufacturer) 100 V AC T5.0AH 250 V / 215 005 / Littelfuse 110 V AC T5.0AH 250 V / 215 005 / Littelfuse 120 V AC T5.0AH 250 V / 215 005 / Littelfuse 220 V AC T2.5AH 250 V / 215 02.5 / Littelfuse...
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About connectors and plugs Balanced pre-output connector SHIELD/GROUND + (HOT) - (COLD) Balanced input connector SHIELD/GROUND + (HOT) - (COLD) XLR4 balanced headphone output connector L (+) L (-) R (+) R (-)
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About connectors and plugs 6.3 mm headphone output plug Tip (Lch) Ring (Rch) Sleeve (GND)
Connecting method Rear panel • The product offers three inputs of audio signal, including two balanced inputs (Balanced 1 and Balanced 2) and one unbalanced input (LINE 1). Balanced audio, commonly used in professional and high-end consumer audio systems, is transmitted as the voltage difference between the non-inverted and inverted signals over three wires, resulting in a cleaner audio signal with reduced noise and interference.
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Connecting method Front panel • The product features one 6.3 mm stereo headphone output terminal on its front panel and one XLR4 balanced headphone output. The headphone outputs can deliver up to 1600 mW of output power per channel and is compatible with headphones that have an impedance of 32 to 600 ohms.
Using the product To start using the product, follow these steps. Connect the audio source to the product using interconnects and attach the headphone cable to the appropriate output terminals securely. Attach the power cable to the rear IEC inlet of the product and plug the other end into a grounded AC power outlet.
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Amplifier circuit block diagram OUTPUT Rch Hot Output Transformer PRE BALANCED INPUT ECC83S+300B Amplifier Impedance Matching Input matrix selector PRE LINE BALANCED1 control circuit Rch Cold Output Transformer ECC83S+300B Amplifier Impedance Matching Output BALANCED to UNBALANCED Selector BALANCED BALANCED2 UNBALANCED to BALANCED &...
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Cautions for using the product as a preamplifier Since this product uses vacuum tubes, sufficient sound quality may not be obtained when loud playback is performed through speakers. To ensure optimal performance, consider the following suggested layouts when using the product output with speakers: If the speaker’s woofer is on the front It is recommended to avoid placing the product directly facing the sounding position of the speaker.
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Cautions for using the product as a preamplifier If the speaker’s woofer is on the rear or side It is recommended to position it in front of or to the side of the listener to prevent sound waves from directly impacting the vacuum tube and causing distortion.
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Cautions for using the product as a preamplifier For even louder playback or better bass If you are looking for even louder playback or better bass from the product, one option is to install acoustic shielding that matches the environment in which it will be used. Acoustic shielding can help to reduce unwanted noise and vibrations that can negatively impact the performance and sound quality of the preamplifier.
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Cleaning • Get into the habit of regularly cleaning the product to ensure that it will last for a long time. • Use a dry cloth to clean the product. Do not use alcohol, paint thinners or other solvents for cleaning purposes.
Troubleshooting In case the equipment is not functioning correctly, please check the following. If the issue persists even after checking the suggested points, be sure to unplug the power cable from the outlet and contact your local Audio- Technica dealer for assistance. Power is not supplied •...
Warranty • The product comes with a three-year warranty against defects in workmanship or materials from the date of purchase. Please note that the warranty is non-transferable. • The warranty is void if the product has been subject to misuse, or negligence or has been modified, repaired or opened by a non-authorized person without the written authorization of Audio-Technica.
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