Alto A500.2 DRAGONFLY User manual

User's Manual
www.altoproaudio.com
Version 1.5 February 2006
LTO
R
English
A500.2 DRAGONFLY DIGITAL POWER AMPLIFIER

1
SAFETY RELATED SYMBOLS
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
This symbol, wherever used, alerts
you to the presence of un-insulated
and dangerous voltages within the
product enclosure. These are voltages
that may be sufficient to constitute the
risk of electric shock or death.
WARNING
Describes precautions that should be
observed to prevent the possibility of
death or injury to the user.
Describes precautions that should be
observed to prevent damage to the
product.
CAUTION
Operating Conditions
Always install in accordance with the
manufacturer's instructions.
This symbol, wherever used, alerts
you to important operating and ma-
intenance instructions. Please read.
Protective Ground Terminal
AC mains (Alternating Current)
Hazardous Live Terminal
ON:
OFF:
Denotes the product is turned on.
Denotes the product is turned off.
1
WARNING
Power Supply
Ensure that the mains source voltage (AC
outlet) matches the voltage rating of the
product. Failure to do so could result in
damage to the product and possibly the user.
External Connection
Do not Remove any Covers
Fuse
To prevent fire and damage to the
product, use only the recommended
fuse type as indicated in this manual.
Do not short-circuit the fuse holder.
Before replacing the fuse, make sure
that the product is OFF and disconnected
from the AC outlet.
Always use proper ready-made insulated
mains cabling (power cord). Failure to do
so could result in shock/death or fire. If
in doubt, seek advice, from a registered
electrician.
Within the product are areas where high
voltages may present. To reduce the risk
of electric shock do not remove any
covers unless the AC mains power cord
is removed.
Covers should be removed by qualified
service personnel only.
No user serviceable parts inside.
Unplug the product before electrical storms
occur and when unused for long periods of
time to reduce the risk of electric shock or
fire.
Protective Ground
Before turning the product ON, make sure
that it is connected to Ground. This is to
prevent the risk of electric shock.
Never cut internal or external Ground wires.
Likewise, never remove Ground wiring
from the Protective Ground Terminal.
Disposing of this product should
not be placed in municipal waste
and should be separate collection.

2
Do not install this product near any direct
heat source.
Do not block areas of ventilation. Failure
to do so could result in fire.
Keep product away from naked flames.
IMPORTANT SAFETY INSTRUCTIONS
Read these instructions
Follow all instructions
Keep these instructions. Do not discard.
Heed all warnings.
Only use attachments/accessories
specified by the manufacturer.
Power Cord and Plug
Do not tamper with the power cord or plug.
These are designed for your safety.
Do not remove Ground connections!
If the plug does not fit your AC outlet seek
advice from a qualified electrician.
Protect the power cord and plug from any
physical stress to avoid risk of electric shock.
Do not place heavy objects on the power
cord. This could cause electric shock or fire.
Cleaning
When required, either blow off dust from
the product or use a dry cloth.
Do not use any solvents such as Benzol
or Alcohol.
For safety, keep product clean and free
from dust.
Servicing
Refer all servicing to qualified service
personnel only.
Do not perform any servicing other than
those instructions contained within the
User's Manual.
To avoid the risk of electric shock and
damage, do not subject this product to
any liquid/rain or moisture. Do not use this
product when in close proximity to water.

Preface
3
Dear Customer,
.
Thank you very much.
LTO AUDIO TEAM
Thanks for choosing LTO A500.2 Amplifier and thanks for choosing one of the results
Of LTO AUDIO TEAM job and researches.
For our LTO AUDIO TEAM, music and sound are more than a job...are first of all
passion and let us say...our obsession!
We have been designing professional audio products for a number of years in cooperation
with many of the world's major brands in audio field.
The LTO line presents unparalleled analogue and digital products made by Musicians
for Musicians in our R&D centers in Italy, Netherlands, United Kingdom and Taiwan.
We provide you with world -class designs, while our software development teams continue
to develop and impressive range of audio specific algorithms.
Because we are convinced you are the most important member of LTO AUDIO TEAM
and the one confirming the quality of our job, we would like to share with you our work
and our dreams, pay attention to your suggestions and your comments. Following this
idea we create our products and we will create the new ones! From our side, we guar-
antee you and we will supply you also in future the best quality, and the best fruits of
our continuous researches and the best prices.
Our A500.2 Amplifier is the result of many hours of listening and tests involving Co-
mMon people, area experts, musicians and technicians.
Nothing else to add, but that we would like to thank all the people that made the LTO
Amplifier a reality available to our customers, thank our designers and all the LTO
Staff, there to make possible the realization of products containing our idea of music
And sound and there to support you, our customers, in the best way, conscious that You
are our best richness.

4
TABLE OF CONTENT
1. INTRODUCTION ............................................................................................5
2. FEATURES .............................................................................................. 5......
3. CONTROL ELEMENTS .................................................................................5
3.1 Front Panel
3.2 Rear Panel
4. .................................................................. 7.....TECHNICAL SPECIFICATION
5. WARRANTY....................................................................................................7

1. INTRODUCTION
5
2
1.5U height and 1/2 rack space, stereo high power amplifier
Fantastic audio quality even with extremely high volume levels
Solid and durable, can be mounted into a cabinet
User-controllable limiter
2x480 Watts on 4 ohms (EIAJ)
x260 Watts on 8 ohms (EIAJ)
2x245 Watts on 4 ohms (RMS)
2 COMBO input connectors are compatible with balanced XLR and JACK
Neutrik Speak-on connectors for outputs
Front panel LED indicators for clip, limit, power on and signal
Accurate level control
Manufactured under QS9000, VDA 6.1 certified management system
2. FEATURES
3. CONTROL ELEMENTS
3.1 Front Panel:
The LTO A500.2 DRAGONFLY is D-class digital Power Amplifier with advanced
features and great efficiency. It delivers tremendous power in a small space, providing
high level performance even under the most demanding conditions. The amplifier
contains two independent channels with separate AC transformer, power supplies and
protection system. Each channel has independent protective circuitry against open
circuit, short Circuit, mismatched loads and over temperature. Thanks to the use of
selected and expensive components, the performance of A500.2 DRAGONFLY is
worth much more than its price.
POWER
ON
OFF
CLIP
SIG
LIMIT
CH1
CLIP
SIG
LIMIT
CH2
30
12
16
20
18
6
22
24
26
28
dB
8
-30
12
16
20
18
6
22
24
26
28
dB
8
-
A500.2
DRAGONFLY
R
LTO
4 5
6
POWER ON
321

6
Power LED
This LED lights up when the unit is powered on.
1
Power Switch
Turn the unit on or off.
2
Level Control for Channels1&2
Adjust the output signal level of respective channel.
3
Clip LED
When the LED lights up, it means the output level of signal is too high and it is
time to reduce the signal level until clip LED turns off.
4
Limit LED
While the unit is limiting the output signal, the LED lights up.
5
Signal LED
When there are signals present in this unit, the LED lights up, or it will be off.
6
3.2 :Rear Panel
Input Connector
These connectors connect the input signal of channel1 and channel 2 separately.
7
Limiter Switch
Set this switch of CHI or CH2 at "ON" position, once the output level is above
maximum output level, the limiter begins, thus keeping consistent output level
of respective channel to protect apparatus. If the switch is set at "OFF", the
limiter doesn't work.
8
Apparaten skall anslutas till
jordat uttag nar den ansluts
till ett natverk
Input: 210-240V 50/60Hz
Fuse: T6.3AL 250V
Power Consumption: 450W
AC INPUT
INPUT POWER OUTPUT
CH.1 CH.2
CH2 4 SPEAKER LOAD MIN.
LIMITER
OFF
ON
CH1
LIMITER
OFF
ON
21
Use only with a 250V fuse
7 9
8
10
11
21
21
21

7
Output Connector
These NEUTRIK connectors are used to connect with your speakers.
9
AC Input
Use it to connect your A500.2 DRAGONFLY to the supplied AC cord only. Please
check the voltage in your country before attempting toconnect the unit with the
main AC.
10
Fuse Holder
The fuse can protect the AC supplies circuit of the equipment.
CAUTION: if there is something wrong with the fuse or the fuse needs to
-change, use only the recommended fuse type as indica ted in
-this unit. If the fuse continues to blow after replacing, discon
tinue using this unit before being repaired.
11
4. TECHNICAL SPECIFICATION
8 ohms per channel(EIAJ)
4 ohms per channel(EIAJ)
4 ohms per channel(RMS)
A500.2 DRAGONFLY
20Hz [email protected]%THD, Stereo Mode
MODEL
Controls FRONT: Power switch, CH1 & CH2 LEVEL knobs
REAR: CH1 & CH2 LIMITER
Indicators (per channel) Power-On: Green LED
Clip: Red LED
Limit: Yellow LED
Signal: Green LED
Connectors of each channel Input: COMBO connector
Output: NEUTRIK Speak-on connector
Power Supply 190-240 Vac~50Hz / 95-120Vac~60Hz
Dimension
Net Weight
5. WARRANTY
1. WARRANTY REGISTRATION CARD
To obtain Warranty Service, the buyer should first fill out and return the enclosed Wa-
rranty Registration Card within 10 days of the Purchase Date.
260W
480W
245W (at THD 1%)
3.85 kg (8.49lb)
314W x 208.5D x 66.6H mm / 12.4" x 8.2" x 2.6"
Input Sensitivity @4 ohms +3dBu

All the information presented in this Warranty Registration Card gives the manufac-
turer a better understanding of the sales status, so as to purport a more effective and
efficient after-sales warranty service. Please fill out all the information carefully and
genuinely, miswriting or absence of this card will void your warranty service.
2. RETURN NOTICE
2.1 In case of return for any warranty service, please make sure that the product is
well packed in its original shipping carton, and it can protect your unit from any
other extra damage.
2.2 Please provide a copy of your sales receipt or other proof of purchase with the
returned machine, and give detail information about your return address and con-
tact telephone number.
2.3 A brief description of the defect will be appreciated.
2.4 Please prepay all the costs involved in the return shipping, handling and insu-
rance.
3. TERMS AND CONDITIONS
3.1 warrants that this product will be free from any defects in materials and/orLTO
workmanship for a period of 1 year from the purchase date if you have comple-
ted the Warranty Registration Card in time.
3.2 The warranty service is only available to the original consumer, who purchased
this product directly from the retail dealer, and it can not be transferred.
3.3 During the warranty service, may repair or replace this product at its ownLTO
option at no charge to you for parts or for labor in accordance with the right side
of this limited warranty.
3.4 This warranty does not apply to the damages to this product that occurred as the
following conditions:
Instead of operating in accordance with the user's manual thoroughly, any
use or misuse of this product.ab
Normal tear and wear.
The product has been altered or modified in any way.
Damage which may have been caused either directly or indirectly by another
product / force / etc.
Abnormal service or repairing by anyone other than the qualified personnel or
technician.
And in such cases, all the expenses will be charged to the buyer.
3.5 In no event shall be liable for any incidental or consequential damages.
LTO
Some states do not allow the exclusion or limitation of incidental or consequential
damages, so the above exclusion or limitation may not apply to you.
3.6 This warranty gives you the specific rights, and these rights are compatible with
the state laws, you may also have other statutory rights that may vary from state
to state.
8

NF02069-1.5
SEKAKU ELECTRON INDUSTRY (H.K.) CO., LTD.
No. 1, Lane 17, Sec. 2, Han Shi West Road, Taichung 40151, Taiwan
http://www.altoproaudio.com Tel: [phone]
email: [email protected] Fax: [phone]
c
All rights reserved to ALTO. All features and content might be changed
without prior notice. Any photocopy, translation, or reproduction of part of this
manual without written permission is forbidden. Copyright 2005 SEIKAKU GROUP
SEIKAKU TECHNICAL GROUP LIMITED