MK Sound SS-150THX operation manual Speaker Phasing Test, Speaker Damage & HOW to Avoid IT

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SS-150THX satellite speaker

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To adjust the attenuation of the Dipole element, connect the positive (+) lead to Terminal 3 and insert a 5 watt resistor between terminals 3 and 4. The resistor can be any value between 2 and 11 ohms. The larger the value of the resistor, the greater the attenuation.

f.Tripole With Maximum Output From All Drivers (2.4 ohm impedance)

Compared to the standard Tripole configuration, the output from the Dipole (side) drivers will be unchanged, but there will be significantly greater output from the Direct (front) drivers.

To get maximum output from all drivers, connect the (+) lead from the amplifier to Terminal 1. Connect a jumper wire between Terminal 1 and Terminal 3. CAUTION: This configuration presents a 2.4 ohm load to the amplifier. Do not use this configuration unless your amplifier is rated to 2 ohms.

g.Direct Radiator Only Mode

There will be very little (virtually no) output from the Dipole (side) drivers.

To operate as a Direct Radiator, connect the (+) lead from the amplifier to Terminal 3. Use no jumper.

Remember, regardless of configuration, the Ground (-) lead must always connect to Terminal 2.

REMOTE SWITCHING OF MODES

If you want to be able to switch between any of the above modes, you can do so by using a speaker level switch box. The specific instructions will vary according to the particular switcher you are using and the , so this is section is intended to be general in nature.

For example, to switch between THX Dipole mode and Tripole mode, connect one wire between Terminal 3 and the switcher Input. Connect a separate wire between Terminal 4 and one of the switcher outputs. For the THX Dipole mode, the switcher output connected to Terminal 4 should be turned off. For the Tripole mode, the switcher output should be turned on. Nothing else should be connected to the switch box, especially your amplifier.

As another example, you can also use a switcher to direct the (+) signal from the amplifier to either Terminal 1 or Terminal 3, to switch between some of the custom modes described above.

CAUTION: DO NOT WIRE THE SWITCH BOX SO TERMINAL 2 CAN BE CONNECTED TO ANY OTHER TERMINAL. If Terminal 2 is connected to Terminal 1, 3, or 4, the output of the power amplifier will be shorted, which will almost certainly damage the amplifier.

8. SPEAKER PHASING TEST

In any system using a subwoofer separate from Satellite speakers, especially in multi-channel surround sound applications, a phasing test must be performed to insure proper phase in the system, in order to achieve optimum sound in the critical bass frequencies.

Therefore, you must have correct phase among all the speakers in the system. We recommend using a test disc to compare the phase of the front channels, surround channels, and subwoofer. Test by comparing the phase between individual channels (starting with the front right and left) until you have established that all units have identical phase.

9. SPEAKER DAMAGE & HOW TO AVOID IT

An important factor to consider with any speaker system is the potential for speaker damage. Even though your SS-150THXs have high power handling ability, they still can be damaged by relatively low powered amplifiers.

While very few M&K speakers ever need service, the vast majority of those returned are not for manufacturing defects. Instead, they are returned because they have been overdriven, and almost always because the amplifier used was driven into clipping distortion. This damage is abuse, and is not necessarily covered under warranty.

This distortion occurs when the demands of the music are greater than the amplifier's power. It can occur at 20 watts with a small amplifier, or at 400 watts with a large amplifier. Regardless, when this happens, the amplifier's output waveform (which usually looks like a smooth arc) is "clipped" off, exhibiting a flat top instead of the arc.

This flat top contains multiples of the original amplified frequencies, sometimes at higher levels than the original signal itself. For tweeters, this can be very damaging, as this distortion is well above the audible range, where you will be unable to hear it, and where the tweeter is more vulnerable to damage.

When an amplifier clips, its sound becomes harsh and grating, and a break-up is often audible in the bass frequencies. It will become uncomfortable to listen to, compared to a slightly lower volume level. When you are listening at high volume levels, be aware of the onset of clipping distortion, and turn the volume down slightly if the

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Contents SS-150THXtripole surround speaker Diagrams Table of ContentsIntroduction Home THX Audio Speaker SystemTripole Surround Speaker Using the SS-150THX Mounting Bracket Installation of Your SS-150THX SpeakersWiring the SS-150THX Basic Wiring With the SS-150THXSS-150THX Speaker HOOK-UP Left Surround Speaker / Right Surround SpeakerWiring the SS-150THX for Tripole Operation Wiring the SS-150THX for THX Dipole OperationTripole or Dipole Operation Very ImportantPlacement When Used in THX Dipole Mode Placement of the SS-150THXAS a Surround Channel SpeakerPlacement When Used in Tripole Mode Position Relative to SeatingCustom Modes & Remote Operation Direct Radiator Only Mode Speaker Damage & HOW to Avoid ITRemote Switching of Modes Speaker Phasing TestSpecifications If YOU Need ServiceCabinet Maintenance USE with Omnimount BracketsSS-150THX Uses Omnimount 53-RST USE with AN Omnimount BracketCustom Modes & Remote Operation