Dayton Audio RS1200 Fascicule

©2007 Dayton Audio

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Most pre-amps and receivers have a stereo line output that 

follows the output level that is set by the system master volume 

control; these outputs would connect to the line-level inputs on 

the subwoofer amp control panel. Many newer multi-channel 

receivers have a dedicated mono subwoofer output, usually 

labeled LFE or Low Frequency Effects. The use of this output 

will permit you to have separate control over the bass output 

of the source, and it also permits you to set a crossover 

frequency. When using an LFE output, use a single cable to 

connect to the LFE input on the sub amp; keep in mind that this 

input bypasses the internal low pass filter on the amplifier. For 

either configuration, the system will operate with the greatest 

linearity and least noise if all gain controls are balanced; that 

is, no single gain control is operating at much more than 50% 

of its total range. If one output is set at 10% and it feeds a 

corresponding input that ends up at 90% then hum, noise, and 

overly sensitive control characteristics may result. 

The RS1200 comes shipped standard for 110V U.S. operation; 

simply connect the included IEC power cord to your wall outlet. 

For 220V input, remove the fuse holder, rotate 180 degrees, 

and re-install. In most 220V applications a separate power cord 

will be required and is not included. When connecting your 

subwoofer for the first time, it is important to remember to start 

with the amplifier OFF and the gain control set at minimum. 

Start some source program that contains good bass material, 

apply AC power to the subwoofer, and slowly increase the gain 

on the sub amp. You should hear a gradual increase in deep 

bass output as you bring up the volume. When the overall 

balance between low and high frequency seems close, adjust 

the phase switch and keep it set where the sub-bass response 

sounds best in your listening location. You may then use the 

parametric equalizer to finish off the general contour of the 

low frequencies, or to correct a troublesome room mode or 

resonance. These steps to achieve an optimum room response 

should be used in conjunction with the steps described in the 

next section, because the physical location of the speaker 

components in the system can affect performance as much as 

the electronic adjustments.

The requirement for the room location of a subwoofer is 

substantially different than what we would expect for full range 

speakers. We are not concerned with stereo imaging due 

to the omnidirectional nature of sub bass, and bass tends 

to fill a room with little bearing on positioning the subwoofer 

in direct line-ofsight. Bass energy is easily reinforced by 

reflection, and as those reflections recombine, the resulting 

buildup can cause very irregular response in the room in the 

form of peaks. Similarly, phase cancellations can occur when 

the sound waves at a specific frequency cause destructive 

interference and cancel each other out, and create holes or 

nulls in the response. Keeping the subwoofer out of the center 

between two opposing walls, and also out of corners, will help 

to achieve the most even, consistent response. Some listeners 

may prefer the “boomier” sound that results from placing a sub 

in a corner, or need the increase in gain to compensate for 

some other factor. It is generally a good idea to avoid placing 

the subwoofer where it is perfectly centered between any two 

opposing parallel planes (two walls; or the floor and ceiling). In 

some cases, moving the enclosure just a few feet can make a 

noticeable difference. 

Aligning the subwoofer along a line drawn between the left/right 

main speakers will help to keep the speakers in the same time 

domain and will improve coherence. When properly integrated, 

the actual location of the subwoofer will disappear and the 

bass will seem to be coming from the main left/right speakers 

on either side. Test tones and measurement equipment can 

help you with your system setup, but good results can also be 

achieved by spending time with a couple of well recorded CDs 

with which you are especially familiar. You may find it useful to 

have an associate make adjustments to the various system 

controls, or even move speaker enclosures, while you remain in 

a consistent listening position. After satisfying yourself that your 

primary location is OK, move around a bit to make sure that 

the wider soundstage is acceptable. There’s no good reason 

why a single high quality subwoofer cannot be used for both 

home stereo and home theatre applications. Each person has 

his or her own individual preference as far as tonality, loudness, 

range, or definition is concerned, and the biggest difference 

between home theatre and home stereo is not the hardware 

as much as how the hardware is used. A typical home theatre 

system will tend to have the output of the subwoofer turned up 

a bit more than what would be appropriate for home stereo. 

Most cinema soundtracks are mixed with the sub-bass dialed 

in to create both musical support and dramatic special effects. 

It is up to you to decide how much you want the Imperial Battle 

Cruisers to shake your house.

The addition of a new active sub to an existing system can 

sometimes result in the subwoofer beginning to hum. While 

it would be easy to assume that the new product is at fault or 

even defective, it is usually just an indicator that it is time to 

take a closer look at the overall grounding of the audio system. 

To start with, verify that all audio equipment in the system is on 

the same AC power circuit. The outlets in a listening area may 

or may not all be on the same breaker, some could even be on 

a completely different breaker panel. Always make sure that all 

equipment grounds are in good condition, and NEVER remove 

the ground pin from a power plug. There are some cases where 

the actual power line has some form of interference but the 

most common cause of noise is a ground loop, meaning that 

the system’s different ground points lack a common potential. 

The cable TV line can be the cause of hum in multi-source 

home audio/video systems. Just temporarily disconnect the 

cable line, and if the hum stops then the use of an inline 

isolation transformer is suggested. Other situations may require 

the installation of an improved earth ground (connection to a 

metal water pipe or grounding rod) in the vicinity of the audio/

video system. The key is to proceed slowly and step by step, 

taking care to identify which cables or combinations of cables 

cause noise when connected.

If bass output seems low, consider the different parts of the 

system that can contribute to gain or volume. Try moving the 

subwoofer to a corner. Make sure that the bass output control 

of the receiver is set correctly (if so equipped). Be sure to use 

a “Y” cord to connect both line level inputs if you are using 

a mono source. Verify that the source that is feeding the 

subwoofer does not have a crossover of its own that is set to a 

lower frequency than the one in the subwoofer speaker.

Frequency Response: 25Hz-200Hz

SPL: 110dB

Amplifier Power Output: 500 Watts RMS

Signal to Noise Ratio: 98 dB A-weighted

Input Impedance: 12K ohms

Dimensions: 17”(W) x 17”(H) x 17-1/4”(D)

Net Weight: 77 lbs.

Power Requirements: 110-120 VAC, 60 Hz. (8A GMA fuse)