Page 2 - FEATURES; Input Level Controls
2 FEATURES Your Optimus 85 × 4 High Power 4- Channel Trunk Mount Amplifier is de-signed to produce a total of 340 wattsto give added punch and power toyour vehicle’s existing stereo sys-tem. The amplifier produces up to 85watts per channel of clean, powerfulsound at all audio frequencies withminimum...
Page 3 - Mute Turn On Circuit; eliminates; Power Indicator; lights when power; Full MOSFET Power Supply; distorts
3 Mute Turn On Circuit - eliminates the irritating thump noise that someamplifiers produce when you turnthem on. Power Indicator - lights when power is on. Full MOSFET Power Supply - pro- duces enough power to supply themain amplifier and has a consider-able amount of reserve power forpeak “high dem...
Page 4 - CONTENTS; Connecting Two Unbridged Speakers
4 CONTENTS Preparation ..................................................................................................... 5 Choosing a Mounting Location .................................................................. 5Before You Begin the Installation .............................................
Page 5 - PREPARATION; CHOOSING A MOUNTING LOCATION; • Does not interfere with the vehicle’s operation.; BEFORE YOU BEGIN THE INSTALLATION; • Which of the amplifier’s wires is the power wire?
5 PREPARATION CHOOSING A MOUNTING LOCATION The ideal location for mounting the amplifier is in your vehicle’s trunk. Whereveryou decide to mount it, choose a mounting location that: • Does not interfere with the vehicle’s operation. • Lets you drill mounting holes without damaging other vehicle comp...
Page 7 - Securely connect the supplied dark; such as a bolt attached to a part of the vehicle’s chassis.
7 2. Securely connect the supplied dark blue/white wire’s spade connector endto the amplifier’s REM (remote power) terminal. 3. Connect the dark blue/white wire’s other end to your autosound system’sswitched power lead using a twist-onterminal connector (such as Cat. No.64-3057, not supplied). Note:...
Page 8 - CONNECTING TO YOUR AUTOSOUND SYSTEM; Low Level Input Connections; low input
8 CONNECTING TO YOUR AUTOSOUND SYSTEM Low Level Input Connections You can connect your autosound system’s low-level phono output jacks to theamplifier’s low-level phono input jacks. For the best results, use shielded audiocables, such as Cat. No. 42-2368 (not supplied). Note: For a cleaner, less noi...
Page 10 - If your autosound system has only two phono output jacks
10 If your autosound system has only two phono output jacks (left and right) and you are using four speakers, use two Y-adapter audio cables to makethe connections as follows: Note: For the best results, use shielded phono plug-to-phono plug Y-adapter audio cables, such as Cat. No. 42-2368 (not supp...
Page 11 - High-Level Input Connections
11 If your autosound system has only two phono output jacks (left and right) and you are using only two speakers, simply connect them to the amplifier’s corresponding CH1 and CH2 , or CH3 and CH4, phono jacks. High-Level Input Connections If your autosoiund system has only speaker outputs, you can c...
Page 14 - CONNECTING THE SPEAKERS; to; Caution: Do not connect the speakers’ negative (; ) terminal wires to chassis; Preparing the Speaker Wires; Strip the insulation from the ends of each conductor to expose; Note: Be sure to twist the ends to secure loose strands.
14 CONNECTING THE SPEAKERS With the speakers placed in their approximate locations, run one speaker wirefrom each speaker to the amplifier. We recommend you use 16- or 18-gaugemarked or color-coded wires to help you correctly connect the speakers to youramplifier. For the maximum bass response and t...
Page 15 - Connecting Four Speakers
15 Connecting Four Speakers 1. Connect one end of a speaker wire’s marked conductor to the amplifier’s CH1 + terminal (front-left positive). 2. Connect the unmarked conductor ’s end to the amplifier ’s CH1 - terminal (front-left negative). 3. Repeat Steps 1 and 2 to connect another speaker wire to t...
Page 16 - Connecting Two Speakers (Unbridged Connection)
16 Connecting Two Speakers (Unbridged Connection) If you are connecting only two speakers, you can connect them to the amplifier’sfront ( CH1 and CH2 ) or rear ( CH3 and CH4 ) speaker terminals. Caution: This is an unbridged connection that produces 85 watts per channel. Ifyou do not have high power...
Page 17 - Connecting Two Speakers (Bridged Connection)
17 Connecting Two Speakers (Bridged Connection) If you are connecting only two speakers (left and right), you can add (bridge) thepower output of two channels (front and back) to produce the combined powerof both from each of the two speakers. Caution: This is a bridged connection that produces 170 ...
Page 20 - TESTING THE CONNECTIONS; immediately; . Then disconnect your vehicle battery’s nega-
20 TESTING THE CONNECTIONS Before you permanently mount the amplifier, connect your vehicle battery’s neg-ative ( - ) cable, turn your vehicle’s ignition to ON or ACC, then test the connec- tions. The amplifier is properly connected to the autosound system and speakers if youcan verify that the ampl...
Page 21 - MOUNTING THE AMPLIFIER; • 6 sheet-metal screws
21 MOUNTING THE AMPLIFIER Before you begin mounting the amplifier, make sure you have the following sup-plied hardware necessary for mounting. • 6 sheet-metal screws • 6 spring washers • 6 flat washers Then confirm that the amplifier fits your vehicle’s mounting area. Caution: Be careful to not dril...
Page 23 - OPERATION; TURNING ON THE AMPLIFIER; try to locate the short.; controls fully counterclockwise to; Note: The right level control adjusts the inputs to; and
23 OPERATION TURNING ON THE AMPLIFIER The amplifier automatically turns on whenever you turn your vehicle’s ignitionswitch to ACC or ON. POWER lights when the amplifier is operating. SETTING THE LEVEL CONTROL For the best performance, you can adjust the level of audio signals that enter theamplifier...
Page 24 - USING THE FREQUENCY CROSSOVER
24 2. Temporarily turn up the autosound system’s volume control to about one- third of its full range. Caution: Never turn the level controls up any farther than you need to getclear sound at two thirds volume maximum. 3. Turn the left and right LEVEL controls clockwise until you can hear the sound ...
Page 25 - MAINTENANCE; Your Optimus 85
25 MAINTENANCE Your Optimus 85 × 4 High Power 4-Channel Trunk Mount Amplifier is an example of superior design and craftsmanship. The following suggestions will help youcare for your (product name) so you can enjoy it for years. Keep the amplifier dry. If it gets wet, wipe it dry immediately. Liq-ui...
Page 26 - REPLACING THE FUSES; might damage your amplifier.; Replacing the Tube-Type Fuse; Grasp the two ends of the power; Replacing a Blade-Type Fuse; Grasp the fuse’s plastic end and pull it
26 REPLACING THE FUSES If the amplifier shuts down, you might need to replace the power wire’s 50-amptube-type fuse, either of the two 25-amp blade-type fuses on the back panel, orall three fuses. Cautions: • Do not use a fuse with ratings other than those specified here. Doing so might damage your ...
Page 27 - SPECIFICATIONS; Input Impedance
27 SPECIFICATIONS 10% THD Output Power @ 14.4 VDC 1 kHz (4 Channel Mode) ........................................................................... 85 W ¥ 4 (Bridged Mode) ........................................................................ 170 Watts ¥ 2 Frequency Response ........................
Page 28 - Printed in Taiwan
RADIO SHACK A Division of Tandy Corporation Fort Worth, Texas 76102 7A5 Printed in Taiwan RADIO SHACK LIMITED WARRANTY This product is warranted against defects for 1 year from date of purchase from RadioShack company-owned stores and authorized Radio Shack franchisees and dealers.Within this period...