IMPORTANT SAFTEY INSTRUCTIONS
Please read the following very carefully before operating this unit












Read ALL instructions carefully before using this unit. Keep these instructions for future reference. Heed all warnings and follow
all instructions.
Do not use this unit near water, in the rain, or where there is moisture. If this warning is ignored a serious electrical shock or
death may occur.
Do not attempt to service this unit. No user serviceable parts inside. Refer servicing to qualified, ISP approved personnel.
Servicing is required when the unit is damaged in any way, such as power supply cord or plug is damaged, liquid has been
spilled or objects have fallen into the unit, the unit has been exposed to rain or moisture, does not operate normally, or has
been dropped.
Do not block any ventilation openings on the unit. Do not install near heat sources such as radiators, heat registers, stoves, or
other apparatus that produces heat.
Do not defeat the grounding pin on the power plug. A grounding type plug has two blades and a third grounding prong. If the
grounded plug does not fit in your outlet, please consult an electrician for replacement of the outlet, which may be obsolete.
Care should be taken to avoid any foreign objects or liquid into this unit. Avoid exposure of this equipment to dripping or
splashing and ensure that no objects filled with liquid, such as vases, are placed on the equipment.
Only use accessories or attachments that are specified by the manufacturer.
Use only with the caster attachment, stand, connecting bracket, or table specified by the manufacturer, or sold as an accessory
with the unit. When a castor attachment is used, use caution when moving the cart/apparatus combination to avoid injury from
tipping over.
To completely disconnect this unit from the AC mains, disconnect the power supply cord plug from the AC receptacle.
This active speaker system has internal power amplifier(s) and a heatsink located internally with cooling ports on the back of
the unit for airflow over the heatsink. Care should be taken to avoid placing this active speaker in a location where the airflow
over the heatsink is impeded and proper cooling of the internal amplifiers is not provided. Avoid placing this system close to
other heat sources. The external heatsink may reach high temperatures under normal use. Do not block the external heatsink
with any other object. Make certain there is proper ventilation for the external heatsink when in use.
Do not drive the unit into excessive heavy distortionfor an extended period of time to avoid premature speaker failure.
Failure to follow these instructions may void the warranty.
THIS UNIT CONTAINS POTENTALLY LETHAL VOLTAGES. TO PREVENT ELECTRIC SHOCK
OR HAZED, DO NOT REMOVE THE POWER AMPLIFIER MODULE, INPUT PANEL OR AC
INPUT PANEL. NO UER SERVICABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED
ISP TECHNOLOGIES SERVICE PERSONNELL.
The lightning bolt triangle is used to alert the user to the risk of electric shock.
The exclamation point triangle is used to alert the user to important operating or
maintenance instructions.
Caution: Exposure to extremely high noise levels can
cause permanent hearing loss.
The LT1, LT1S and LT1XF speaker system is capable of producing in excess of 129db SPL at
1 meter. Continued exposure to noise levels in excess of 90db may cause permanent hearing
loss. Below is a chart of the OSHA (Occupational Safety & Health Administration) regulations
for Occupational Noise Exposure. Please note: OSHA requires hearing protection for any
work environment when the sound levels exceed those shown in Table G-16 when measured
on the A scale of a standard sound level meter at slow response.
INTRODUCTION
Thank you for purchasing ISP Technologies LT1 active speaker system. The LT1 is a high
output three-way active speaker system designed to deliver HI-FI sound quality for high SPL
sound reinforcement applications. The LT1 is designed with a 500 watt 12 inch woofer, a 225
watt 8-inch midrange driver and a high performance, 2 inch high frequency compression driver.
The LT1 has three separate power amplifiers capable of producing upwards of 900 watts of
power. Each amplifier receives its input signal from an internal 4th order crossover network
specifically designed to provide optimized phase and frequency response at each crossover
point. The internal amplifiers are based on ISP Technologies patent pending D-CAT
(Dynamic Current Amplifier Technology) amplifier technology. The D-CAT technology is
capable of delivering extremely high output current providing an improvement in transient
response, output current and a noticeable improvement in PUNCH. The D-CAT amplifier
technology utilizes a monolithic power amplifier driver that reduces parts count and greatly
improves reliability. The D-CAT amplifiers provide improved reliability by including short circuit
and over temperature protection.
The LT1 offers both ¼ inch RTS and XLR balanced inputs as well as, ¼ inch RTS and XLR
outputs for connecting multiple speakers. A sensitivity adjustment knob allows you to adapt
the speaker for a wide range of common signal levels. The Tripower cabinet is made of high
quality 13 ply Baltic birch plywood with a durable spray on black finish for long life.
SUSPENDING LOUDSPEAKERS
Important Notice!!!
The information in this section has been gathered from engineering data and is for
informational purposes only. None of the information in this section should be used without first
obtaining competent advice with respect to applicability to a given circumstance. None of the
information presented herein is intended as a representation of warranty on the part of ISP
Technologies. Anyone making use of this information assumes all liability arising from such
use.
All information presented in this manual is based upon materials and practices that are most
common to The United States of America and may not directly apply to other countries
because of differing material dimensions, specs, and/or local regulations. Users in outside
countries should consult with appropriate engineering and regulatory authorities for specific
guidelines.
Correct use of all flyware is required for secure system suspension. Careful calculations should
always be performed to ensure that all components are used within their working load limits
before the cabinet suspended. Never exceed the maximum load ratings.
Before hanging any speaker system, always inspect all components for cracks, deformations,
corrosion, missing, loose or damaged parts that could reduce strength and safety of the
cabinet. Do not suspend the cabinet until the proper corrective action has been taken.
ATTACHMENT TO STRUCTURES
A licensed professional engineer must approve the placement and method of attachment to
the structure prior to the installation of any overhead object. The following performance
standards should be provided to the professional engineer for design purposes; Uniform
building code as applicable, Municipal Building code as applicable and Seismic Code as
applicable.
INSPECTION and MAINTENANCE
Suspension systems are comprised of mechanical devices and, as such, they require regular
inspection and routine maintenance to insure proper function ability. Any suspended ISP
Technologies loudspeaker must be inspected for fatigue at least annually. The inspection shall
include a visual survey of all corners and load bearing surfaces for signs of cracking, water
damage, de-lamination, or any other condition that may decrease the strength of the
loudspeaker enclosure.
Flyware that is provided with or for any ISP Technologies loudspeakers must be inspected for
fatigue at least annually. The inspection shall include a visual survey of the material for signs
of corrosion, bending, or any other condition that may decrease the strength of the fastener.
ISP Technologies is not responsible for the application of its products for any purpose or the
misuse of this information for any purpose. ISP is also not responsible for the abuse of its
products caused by avoiding compliance with inspection and maintenance procedures.
REAR PANEL DESCRIPTION
1. POWER SWITCH-This switch provides power to the Tri-Power power amp section. This
switch is a three-position switch where center is OFF and the outer positions are ON.
2. POWER INLET MODULE-This module provides a connection for the power cord and also
houses the mains fuse. (See Fuse Replacement Section)
3. INPUT GAIN- This control determines the overall input level of the signal to the power amp
section of the Tri-Power cabinet. Adjusting this level will not affect the level of the signal
passing through to output connectors.
4. BALANCED ¼” PHONE INPUT-This jack provides an input for balanced or unbalanced
line level signal source.
5. BALANCED XLR INPUT-This female XLR connector provides an input for balanced line
level signal source
6. BALANCED ¼” PHONE OUTPUT – This ¼” phone provides a balanced loop through for
connecting to additional powered cabinets.
7. BALANCED XLR OUTPUT- This XLR male provides a balanced loop through for
connecting to additional powered cabinets.
FUSE REPLACEMENT
1. Use a small screwdriver as shown to slide the fuse
cover out from the power inlet module. The fuse can be found inside the fuse cover module
after it is pulled out.
NOTE: A SMALL COMPARTMENT IS ALSO PROVIDED WITHIN THE FUSE
COVER MODULE FOR STORING A SPARE FUSE.
2. After replacing the fuse with another of identical
specifications, push the fuse cover module fully back into
place, ensuring that the fuse has snapped onto the fuse
holder inside the power inlet module.
CONNECTION DIAGRAM
BALANCED CONNECTION DESCRIPTION
The ISP Tripower series has balanced XLR and ¼” phone inputs and outputs configured to
AES standards (Audio Engineering Society). These connections are connected in a loop
through configuration and will accept a balanced line-level input. The standard phase
configuration is that pin 2 is (+), pin 3 is (-), and pin 1 is shielded ground on the XLR. On the ¼”
phone jacks the configuration is Tip is (+), Ring is (-), and Sleeve is ground.
NOTE: IF AN UNBALANCED SIGNAL SOURCE IS USED, THE MALE XLR AND ¼” PHONE
OUTPUTS FOR LOOPING THROUGH TO ADDITIONAL POWERED CABINETS WILL ALSO BE
UNBALANCED.
THERMAL CONDITIONS
The ISP LT1 Series is capable of producing in excess of 900 watts at full power. This
generates heat that must be dissipated in order to maintain reliability and insure the amplifier
components stay within their operating temperature specs. To accomplish this the amplifier is
mounted on a heatsink that is exposed on the rear of the cabinet. Airflow is forced through a
bass port at the bottom of the fins of the rear heatsink via the air movement from the 12”
speaker. It is recommended that the fins have at least 6 inches of clearance from any
obstruction to allow proper ventilation to occur.
In addition the amplifiers are thermally protected internally via a thermal switch, which will
attenuate the signal 40db if the heatsink temperature exceeds a certain temperature. When
the temperature drops below a certain point, full signal will be restored. Tests have shown
under extreme conditions that cycling will occur approx. (40 sec. ON, 20 sec. OFF)
Under extreme conditions, such as when ambient temperatures are too high (hot rooms,
extreme outdoor temperatures) it is recommended to use a fan on the fins to reduce the
cycling effects.
It should also be noted that a separate internal thermal breaker also protects the power
transformer. If the power transformer temperature reaches a critical point the internal thermal
breaker will open. The power LED on the front of the cabinet will go out and the LT2 will shut
down for several minutes while the power transformer cools. If this condition occurs simply
reduce the signal level of the system. This will only occur if the LT1 is continually pushed into
heavy distortion.
NOTE: The power transformer inside the LT1 contains an enamel coating on the wires.
During the first several hours of heavy use the LT1 may have a slight odor caused by the
enamel on the transformer wires heating.
SPECIFICATIONS
System
Frequency Range
Frequency Response (-3dB)
Horizontal Coverage Angle
Vertical Coverage Angle
Peak Output @ 1m
Crossover Points
Input Type
Input Impedance
Thermal Protection
Transducers
Low-Frequency Transducer
Diameter
Voice Coil Diameter
Power Handling
Mid-Frequency Transducer
Diameter
Voice Coil Diameter
Power Handling
High-Frequency Transducer
Diaphragm Diameter
Voice Coil Diameter
Throat Size
Power Handling
Diaphragm Material
Power Amplifiers
Low-Frequency Amplifier
Power Output
THD
Mid-Frequency Amplifier
Power Output
THD
High-Frequency Amplifier
THD
45Hz - 20KHz
50Hz - 19KHz
100 degrees.
65 degrees.
129 dB
350 Hz, 2.6KHz
Balanced differential
10K ohms
Output Drivers have internal protection, self-resetting. Heatsink
temperature monitored and input is muted if safe temperature is
exceeded, self-resetting. Transformer has internal thermal fuse, selfresetting.
12” (381mm)
3” (76.2mm)
500 watts rms
8” (254mm)
2.5” (63.5mm)
225 watts rms
2” (51mm)
2” (51mm)
1” (25.4mm)
80 watts rms
Titanium
300 watts rms
<0.05% typical
300 watts rms
<0.05% typical
100 watts rms
<0.02% typical
Line Input Power
Voltage
Current
Power
117Vac, 60 Hz
6.9 amps
800 watts
Physical
Height
Width
Depth
Weight
Enclosure
Mounting Methods
19.75”
30.54”
19.5”
120 lbs.
18mm thick, 13 ply Baltic Birch plywood
3/8 eyebolt suspension
WARRANTY AND SERVICE
The unit, parts and workmanship are fully guaranteed to be free of defects under normal use
and service for a period of three years from the date of purchase. The Internal Speakers that
are used in this pro audio cabinet are fully guaranteed to be free of defects under normal use
and service for a period of three years.
Any damage resulting from the misuse or the failure to follow the precautions and instructions
will void the warranty.
In the event that the unit needs to be repaired, Please return the unit to ISP Technologies
directly. Simply repack the unit, send a copy of the original receipt, a note stating the problem,
and send it to:
ISP Technologies, LLC
5479 Perry Drive Suite B
Waterford, MI 48329
Attn: Repair Dept.
All shipping charges must be fully prepaid.
ISP will not be responsible for any damages incurred in shipping of any unit. Any claim will
need to be settled with the shipping company.
The warranty will be voided if the serial number has been tampered with in any way.
NOTE: This Product may be covered under one or more of the following patents or patents
pending: 7,035,413; 6,944,305; 6,931,134; 6,831,514; 6,091,013
Should you have any questions for the repair department prior to returning the product please
call 1-(248)-673-7790
NOTE: If it is determined that the power amp module has failed, it is possible for an ISP
certified service center to remove the module from the cabinet by removing the mounting
screws and disconnecting the speaker terminals and the transformer. The module may be sent
back to ISP separately. Please contact ISP for technical support to help determine if the
amplifier module may be defective.
ISP TECHNOLOGIES, LLC
5479 Perry Drive Suite B
Waterford, MI. 48329
248-673-7790
FAX: 248-673-7696
www.isptechnologies.com