Nady Systems HPA-4 User Manual 2

HPA-4

RACK GEAR

4 CHANNEL HEADPHONE/AMPLIFIER/LINE DISTRIBUTOR

HPA-4

4 CHANNEL HEADPHONE/AMPLIFIER/LINE DISTRIBUTOR

Congratulations on your choice of headphone/amplifier/line distributor — you have purchased one of the finest stereo headphone/am­plifier/line distributors on the market today. This unit was developed using the expertise of professional sound engineers and working
musicians. You will find that your new NADY AUDIO HPA-4 has superior performance and greater flexibility than any other headphone/
amplifier/line distributors in its price range. Please read this manual carefully to get the most out of your new unit.

Thanks for selecting NADY AUDIO as your choice in headphone/amplifier/line distributor.

FEATURES

With extensive switching functions, extreme efficiency, and unmatched sound quality, the ultra-versatile HPA-4 is a universal 4-channel
multi-purpose headphone amplifier/line distribution system—perfect for the most demanding professional stage and studio applications.

• Four totally independent stereo high-power headphone ampli­fier/line distribution channels in a convenient single rack pack­age—an ingenious, easy-to-operate unit allowing a maximum
variety of both useful monitoring and stereo line level signal dis­tribution options.

• Input Source Select switches and Phone and Line 1/4" TRS ste­reo outputs on each channel, and 4 independent stereo input
sections (each with servo-balanced L & R 1/4"TRS jacks) en­able independent selection of any of the 4 stereo signals for
each headphone amp/line distribution channel. This allows se­lecting from up to 4 completely independent monitor signals for
each set of headphones connected to the HPA-4 for optimum
monitoring flexibility or 4 separate choices for each channel’s
Line Output for enabling many useful, simple audio switching/
routing solutions.

• Separate Volume control for each channel adjusts the level to
both Phone and parallel Line outputs

• Easily expandable for optimum versatility in any application—up
to four HPA-4’s can be daisy chained for additional fully select­able headphone/line distribution requirements

• No-compromise circuit design, stringently selected tight-toler­ance components and low-noise, extremely linear or amps for
reference-quality, transparent audio with maximum headroom
even at extremely high headphone volume levels

• High-quality, rugged construction for maximum reliability

• Shielded internal dual regulated power supply with
~115V(60Hz)/~230V(50Hz) select switch and fused IEC power
cord connector

TABLE OF CONTENTS

FEATURES................................................................................. 2

WARNING................................................................................... 3

INSTALLATION .......................................................................... 4

FRONT & REAR PANEL CONNECTIONS ................................ 5

CONTROLS & INDICATORS ..................................................... 5

APPLICATIONS.......................................................................... 6

1. Using the HPA-4 as a headphone amplifier .......................... 6

2. Using the HPA-4 as a line distribution unit............................ 6

3. Daisy chaining multiple HPA-4’s together for additional

headphone/line distribution requirements ............................. 6

SPECIFICATIONS ...................................................................... 6

NOTES........................................................................................ 7

Date of Purchase ____________________________________
Dealer’s Name ______________________________________
City _______________________________________________
State _____________________ Zip _____________________
Model # ____________________________________________
Serial # ___________________

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WARNING

An equilateral triangle enclosing a lightening flash/arrowhead symbol is
intended to alert the user to the presence of uninsulated “dangerous
voltage” within the product’s enclosure which may be of sufficient

ATTENTION: RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR

magnitude to constitute a risk of electric shock.

An equilateral triangle enclosing an exclamation point is intended to alert
the user to the presence of important operating and service instructions in
the literature enclosed with this unit.

IMPORTANT SAFETY INSTRUCTIONS

When using this electronic device, basic precautions should always be taken, including the following:

1. Read all instructions before using the product.

2. Do not use this product near water (e.g., near a bathtub, washbowl, kitchen sink, in a wet basement, or near a swimming
pool, etc.).

3. This product should be used only with a cart or stand that will keep it level and stable and prevent wobbling.

4. This product, in combination with headphones or speakers, may be capable of producing sound levels that could cause
permanent hearing loss. Do not operate for a long period of time at a high volume level or at a level that is uncomfortable.
If you experience any hearing loss or ringing in the ears, you should consult an audiologist.

5. The product should be positioned so that proper ventilation is maintained.

6. The product should be located away from heat sources such as radiators, heat vents, or other devices
(including amplifiers) that produce heat.

7. The product should be connected to a power supply only of the type described in the operating instructions or as marked on the
product. Replace the fuse only with one of the specified type, size, and correct rating.

8. The power supply cord should: (1) be undamaged, (2) never share an outlet or extension cord with other devices so that the
outlet’s or extension cord’s power rating is exceeded, and (3) never be left plugged into the outlet when not being used for
a long period of time.

9. Care should be taken so that objects do not fall into, and liquids are not spilled through, the enclosure’s openings.

10. The product should be serviced by qualified service personnel if:
A. The power supply cord or the plug has been damaged.
B. Objects have fallen into, or liquid has been spilled onto the product.
C. The product has been exposed to rain.
D. The product does not appear to operate normally or exhibits a marked change in performance.
E. The product has been dropped, or the enclosure damaged.

11. Do not attempt to service the product beyond what is described in the user maintenance instructions. All other servicing should
be referred to qualified service personnel.

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