Zesto Audio EROS 300 User manual

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EROS 300
Class A Monaural Power Amplifier
Owner’s Manual
Please read carefully before
installing and operating this equipment
Zesto Audio
3138 Calle Estepa
Thousand Oaks, California 91360
805-807-1840
www.zestoaudio.com
[email protected]
Made in the USA
Using US and Imported Parts

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Dear Music Lover,
I wanted to personally thank you for your purchase of my EROS 300 Monaural Power Amp.
I have loved music all my life –as a musician, record producer and audio engineer. That makes me fussy about sound.
That’s a good thing.
Each unit is built by hand with precision and pride to produce the most enjoyable listening experience for you.
I am proud to put my name on it and honored to share this with you.
Wishing you many happy years of listening!
Sincerely,
-- George Counnas, President of Zesto Audio
FYI:
Zesto is Greek for hot
EROS is the God of Love and Desire in Greek mythology
Table of Contents
Thank You …………………………………….. Page 2
Table of Contents……………………………… Page 2
What’s in the box……………………………… Page 3
Warning and Caution…………………………. Page 3-5
Parts and Controls……………………………. Page 6
Specifications ……………………………..…. Page 7 & 8
Proper Care of your EROS 300 Power Amp Page 8
Hookup, Settings and Adjustments……….. Page 9
Tips and Tricks ………………………………. Page 9 & 10
Warranty Information……………………….. Page 11

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What’s in the box?
EROS 300 Monaural Power Amp
6 KT88 Vacuum Tubes
2 ECC82 (12AU7) Vacuum Tubes
White glove for handling tubes
IEC power cable 6’
Not Included: Interconnect or speaker cables
Warning and Caution
WARNING: The triangle with the lightning flash symbol displayed on the unit advises the user of dangerous uninsulated
voltage inside the product’s enclosure.
CAUTION: To reduce the risk of electric shock, do not remove the cover. There are no user-serviceable parts inside; it is
recommended that only qualified personnel service this component.
1. OWNER’S MANUAL: Before powering up the equipment, read all safety and operating instructions and follow them as
instructed. Retain the safety and operating instructions for future reference.
2. ATTACHMENTS: Use only those attachments recommended by the unit manufacturer, as others may cause hazards.
3. ACCESSORIES: Do not place the unit on an unstable cart, stand, tripod, bracket, or table. The unit may fall, causing
injury to a person or damage to the unit. Mount the unit according to the manufacturer’s instructions with the
suggested mounting accessory.
4. WALL OR CEILING MOUNTING: Do not mount the unit on a wall or ceiling.
5. WATER AND MOISTURE: Do not use the unit near water (for example, near a swimming pool, bath tub, wash bowl,
kitchen sink, or laundry tub) or in a damp environment (like a basement or outside in the rain).
6. OBJECT AND LIQUID ENTRY: Do not push objects of any kind into the unit through openings as they could touch
dangerous voltage points and short-out parts, possibly resulting in a fire or electric shock. Do not spill liquid of any
kind on the unit. If water or any metal object (such as a paper clip, coin, or staple) accidentally falls inside the unit,
disconnect it from the AC power source immediately and contact Zesto Audio for further instructions.
7. HEAT: Position the unit away from heat sources such as radiators, heat registers, stoves, or other units (including
amplifiers) that produce heat.

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8. VENTILATION: Slots and openings in the enclosure create ventilation to protect the component from overheating. All of
these openings must remain unobstructed. Allow at least 12 inches of clearance above the unit, 1 inch below and an
opening behind the unit for airflow. Do not place the unit on a bed, sofa, rug, built-in bookcase, or rack without
adequate ventilation.
9. GROUNDING OR POLARIZATION: As a safety feature, the unit may be equipped with a polarized alternating current
line plug in which one blade is wider than the other and a has an additional grounding blade. This plug will fit into the
power outlet only one way. If you cannot insert the plug fully into the outlet, try reversing the plug. If the plug still will
not fit, contact a licensed electrician to update your outlet. Do not defeat the safety purpose of the polarized plug.
10. POWER SOURCES: Operate the unit only from the power source indicated on the marking label on the back of the
unit. If you are unsure of the type of power supplied to your home, consult your unit dealer or local power company.
11. POWER CORD PROTECTION: Arrange power supply cords so that they do not suffer from foot traffic or pinching by
items placed on or against them. Pay close attention to cords where plugs enter the AC outlet and where they exit
from the unit.
12. LIGHTNING: For added protection during a lightning storm or when the component is idle for long periods of time,
unplug the unit from the wall outlet. This will help protect the unit from lightning and power line surge damage.
13. POWER LINES: Do not locate an outside antenna system in the vicinity of overhead power lines or other electric light
or power circuits. When installing an outside antenna system, take extreme care to avoid touching the power lines or
circuits; contact with them could be fatal.
14. OVERLOADING: Do not overload wall outlets, extension cords, or integral convenience receptacles as this increases
the risk of fire or electric shock.
15. REPLACEMENT PARTS: When replacement parts are required, be sure the service technician has used
replacement parts specified by the manufacturer or those having the same characteristics as the original parts.
Unauthorized substitutions may result in fire, electric shock or other hazards.
16. SAFETY CHECK: Upon completion of any service or repairs to the unit, ask the service technician to perform safety
checks to ensure the unit is in proper operating condition.
17. IMPORTANT SAFETY NOTE:
• Before connecting a new product such as the EROS 300 to your audio or home theater system, turn off all other
equipment (preferably unplugging them from the AC power source). Many audio components feature automatic
turn-on circuits that may activate during an installation, potentially causing damage to electronic components or
speakers. This type of damage is not covered by product warranties, and Zesto Audio specifically disclaims
responsibility for any such damage.
• Power Cord: The removable IEC power cord provided with your unit was specifically designed for use with this
product, but other AC cords may be used. Consult your dealer for advice on AC power cords and high quality wire
in your system.
• AC Fuse: The fuse is located inside the IEC power entry connector and is user replaceable. Only replace fuse with
the exact same type that was removed. Only use slow blow fuse. If the unit does not power up, contact an
authorized service representative.
•Wiring: Cables running inside walls should have the appropriate markings to indicate compliance and listing by the
UL, CSA or other standards required by the UL, CSA, NEC, or your local building code. Questions about cables
inside of walls should be directed to a qualified custom installer, licensed electrician, or low-voltage contractor.

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18. RECORDING COPYRIGHT: Recording of copyrighted material for other than personal use is illegal without
permission of the copyright holder.
19. FCC INFORMATION FOR USER:
• CAUTION: Any changes or modifications not expressly approved by Zesto Audio could void the user's authority to
operate the equipment.
• These limits are designed to provide reasonable protection against harmful interference in a residential installation.
This equipment generates and can radiate radio frequency energy, and if not installed and used in accordance
with the instructions it may cause harmful interference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation. If this equipment does cause harmful interference to
radio or television reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the equipment.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from where the receiver is connected.