CT80-SUB Owner's Manual – Rockville Audio

CT80-SUB 8˝ 70V/100V Commercial/Restaurant Subwoofer

The Rockville CT80-SUB subwoofer is a great choice for any restaurant, office, retail store, or other commercial application. This subwoofer will make a great addition to any 70V speaker setup.

Functions

Detailed Alt Text (Best for product manuals or technical documentation): Black-and-white line illustration of a Rockville CT80-SUB subwoofer from two angles, labeled with numbered circles: 1: A metal mounting bracket attached to the upper side of the left subwoofer cabinet. 2: A volume control knob on the rear control panel labeled "ROCKVILLE CT80-SUB". 3: Screw-type input terminals located on the lower right of the rear panel labeled "70V/100V" and "COM". 4: A circular bass reflex port located near the top center on the front panel of the right subwoofer view.

Choosing the Appropriate Tap

70-volt systems are the number one choice for any application for which you want to install multiple speakers. With 70 volt there are a lot of advantages over 4-ohm systems. One of the main advantages is the simplicity of the wiring, as well as how easy it is to match up the speakers with an amplifier. You always want your 70-volt amp to have at least 15% or 20% more power than the combined watts your speakers are tapped at. For example, if you have a 200-watt /70-volt amplifier, you can install five 70-volt speakers that are tapped at 20 watts each or fifteen 70-volt speakers that are tapped at 10 watts each as long as they total close to 175 watts. When we say the word “tap”, what we are referring to is the selector knob on the back of the CT80-SUB. It allows you to set how many watts the built-in transformer will allow the sub to get from the amplifier. The taps set at 10, 20, and 40 watts for 70-volt input; 15, 25, and 55 watts for 100-volt input. This range of taps allows for full customization of the sound for the space where the speakers are installed. In a restaurant, for example, you can tap your dining room speakers at 20 watts, the speakers in the outside seating area at 40 watts, and the ones in the hallway and bathrooms at 10 watts. Another great feature of 70-volt speakers is that you can mix and match any type,
whether they are wall-mounted speakers (such as these), ceiling speakers, subwoofers, etc.

Another benefit of 70-volt speaker setups is the ability to run very long lines of speaker wire without signal loss. And, the wiring is very simple. You just connect all the positive terminals of the speakers to the positive 70-volt terminal(s) of the amplifier. The negative terminals on the speaker get connected to the negative (COM) terminal(s) of the amp. You do not have to worry about impedance as the power is constant.

Setup

70V/100V Speaker Configuration

The total number of speakers multiplied by the tap value cannot exceed the output power (in watts) of your 70V amplifier. The example on the facing page shows four total speakers and the CT80-SUB. Using the 20W taps, you will need an amplifier with at least 100 watts (5 x 20 = 100W). A good rule of thumb is to select an amplifier with 15% to 20% greater power; in this case, an amplifier that delivers about 120W.

4 Speakers and 1 CT80-Sub connected in parallel using 15W taps

Black-and-white wiring diagram illustrating a parallel setup connecting an amplifier to four speakers and one subwoofer: * **Amplifier Connections:** The amplifier output shows two main leads labeled "COM (Negative)" with a minus symbol and "70V/100V" with a plus symbol. * **Speaker Wiring (Parallel Setup):** Four oval-shaped speakers are lined up horizontally in a row. The top wire from the amplifier's positive "70V/100V" terminal connects in parallel across the positive (+) terminal located at the top of each speaker. The bottom wire from the amplifier's negative "COM" terminal connects across the negative (-) terminal at the bottom of each speaker. * **Subwoofer Connection:** A subwoofer positioned on the far right is wired into the same circuit, with its positive terminal connecting to the "70V/100V" positive line and its negative terminal connecting to the "COM" negative line.

Installation

Tools needed:

Phillips screwdriver, drill, wire strippers, pliers, ladder

The CT80-SUB can be wall-mounted on a variety of surfaces. Make sure to place the mounting bracket at a height that will provide enough clearance for the enclosure and will allow the subwoofer to be tilted as needed.

Flat Surface

Make sure the CT80-SUB is on a flat, stable surface. Bass frequencies are omnidirectional, so the subwoofer can be placed anywhere. Try placing it near a wall or a corner for increased bass.

Drywall/Masonry

1. Using the swivel bracket mounting plate as a template, mark the mounting screw locations (fig. a). When mounting to drywall, we recommend you use a stud finder to locate the wall studs and mark their location. Drill pilot holes for the screws (fig. b). If you are installing on masonry or between studs, we recommend using anchors (included). Be sure to use the proper drill bit size for the anchors. Use no less than two anchors to secure the mounting bracket.

Two-panel installation diagram labeled "1" in the top-left corner showing wall bracket installation steps: fig. a (Marking holes): A pencil marks drilling locations through the screw holes of a rectangular metal mounting bracket held against a wall. The bracket features four corner mounting holes and central top/bottom mounting flanges. fig. b (Drilling holes): A hand holds a power drill, drilling into one of four marked dots on the wall corresponding to the bracket's mounting hole locations.

2. Assemble the swivel bracket by sliding the swivel bracket base into the swivel bracket (fig. c). Next, use the included bolt assembly to secure the base to the bracket as indicated in figure d. Please note, there is a special material applied to the threads of the bolts to help keep them tight when you are screwing on the nut and to keep the nut from coming loose due to vibrations from audio playback. You may feel a bit of resistance and that is normal. To facilitate the process, use a pair of pliers (not included) to hold the nut in place while you tighten the screw with the included wrench.

Two-panel assembly diagram labeled "2" in the top-left corner showing wall bracket assembly steps: * **fig. c (Aligning brackets):** A dashed arrow shows the speaker-side mounting bracket fitting inside the U-shaped wall-mount base bracket. * **fig. d (Securing hardware):** An exploded view showing hardware insertion: two cylindrical spacers slide vertically into the inner bracket, two long hex bolts with washers insert horizontally through the outer bracket slots and internal spacers, and two washers with hex nuts attach to the threaded ends of the bolts to hold the assembly together.

3. Now attach the swivel bracket assembly to the subwoofer cabinet. Unscrew the pre-mounted screws and align the holes on the bracket to the predrilled holes on the back panel of the cabinet. Use the screws to attach the bracket. Make sure that the screws are properly seated and that the bracket is securely mounted.

Two-panel assembly diagram labeled "3" in the top-left corner showing how to attach the bracket assembly to the subwoofer: * **Left Panel (Screw removal):** Dashed arrows indicate the removal of four pre-installed Phillips screws from the side of the subwoofer cabinet directly above the "ROCKVILLE CT80-SUB" backplate. * **Right Panel (Bracket attachment):** Dashed arrows show the four Phillips screws being re-inserted through the mounting flange holes of the assembled metal bracket to secure it flush against the side of the subwoofer cabinet.

4. Attach the swivel bracket mounting plate to the swivel bracket assembly.

Single-panel assembly diagram labeled "4" in the top-left corner showing the final step to join the wall bracket and speaker bracket: * **Hinge Pin Assembly:** A dashed vertical arrow shows a long hex bolt with a flat washer being inserted downward through the aligned top and bottom mounting tabs of the wall-plate bracket and the subwoofer-side bracket. * **Securing Hardware:** At the bottom end of the bolt, a second flat washer and a hex nut are shown aligning with a dashed arrow pointing down, indicating how to thread and tighten the nut to secure the vertical pivot point.

5. Finally, attach the unit to the wall where you drilled the mounting screw holes. Make sure to use all four screws to secure the unit to the wall.

Single-panel installation diagram labeled "5" in the top-left corner showing wall mounting of the subwoofer assembly: Fully Assembled Bracket: The bracket assembly is completely attached to both the side of the subwoofer cabinet and the vertical wall plate hinge. Wall Fastening: A screwdriver drives a wood/wall screw horizontally (indicated by a dashed arrow) through the lower mounting hole of the vertical wall plate to secure the entire subwoofer assembly to the wall.

Wiring

Bracket Adjustments

Vertical Adjustment

The CT80-SUB has a vertical adjustment radius of 80 degrees. To adjust the vertical angle of the cabinet, loosen the bolts (a) and adjust the bracket (fig. 1) up or down (fig. 2). Once you have attained the proper angle, tighten the bolts.

Diagram illustrating bracket angle adjustment capabilities in three views: * **fig. 1 (Upward Tilt):** Shows the bracket tilted upward. Curved arrows around two side hex bolts labeled "**a**" indicate loosening the bolts to pivot the bracket upward along curved tracks, achieving up to a 40° angle from the center horizontal axis. * **fig. 2 (Downward Tilt):** Shows the bracket tilted downward. Curved arrows around the side hex bolts labeled "**a**" indicate pivoting the bracket downward along the curved tracks, achieving up to a 40° angle below the center horizontal axis. * **Far Right View (Total Range of Motion):** Demonstrates the combined total vertical tilt range, with dashed guidelines and a curved double-headed arrow illustrating a full 80° angle of motion (40° up and 40° down).

Horizontal Adjustment

The CT80-SUB has a horizontal adjustment radius of 80 degrees. To adjust the horizontal angle of the cabinet, move it left (fig. 1) or right (fig. 2) to the desired position.

Diagram illustrating horizontal swivel adjustment capabilities of the mounting bracket from a top-down view: * **fig. 1 (Left Swivel):** Shows the bracket swiveling horizontally to the left around its central pivot bolt. A dashed guideline and curved arrow indicate a range of up to 40° from the center line, with a faint outline showing the bracket rotated in that direction. * **fig. 2 (Right Swivel):** Shows the bracket swiveling horizontally to the right around the central pivot bolt. A dashed guideline and curved arrow indicate a range of up to 40° to the right of the center line, with a faint outline showing the rotated position. * **Far Right View (Total Horizontal Range):** Demonstrates the combined horizontal panning range, with dashed guidelines forming an arc and a curved double-headed arrow showing a total 80° swivel angle (40° left and 40° right).

Features/Specifications

Can be placed on the floor or mounted to a wall with included wall-mount bracket
Built-in 70V/100V Transformer
20oz Magnet
Banana binding post terminals accept banana cables or regular speaker wire
40W, 20W, 10W selectable with 70V input
55W, 25W, 15W selectable with 100V input
Bypass option to run sub at 4 ohm: 80W RMS @ 4 ohm
Frequency Response: 40Hz – 800Hz
Sensitivity: 90dB (1W @ 1m)
Includes high quality mounting bracket
Unit Dimension: 12.4˝ x 9.65˝ x 12.4˝
Unit Weight: 12.9LBS

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