Tapco 6925 User Manual

Protection

A protection circuit is built into the 

6912, 6915, and 6925 to protect their high-

frequency compression drivers from excessive 

power. When tripped, the protection circuit 

substantially reduces the power to the 

HF driver. After the driver cools to a safe 

operating temperature, the protection 

circuit resets and normal operation resumes. 

However, if the protection circuit senses 

excessive power, it will trip again. In this case, 

it is necessary to reduce the power to the 

loudspeaker by either turning down the gain 

controls on the power amplifier or turning 

down the master volume control on the mixer 

or other sound source.

CAUTION: The protection 

circuit is designed to 

protect the HF driver under 

reasonable and sensible 

conditions. Should you 

choose to ignore the warning 

signs (i.e., frequent clip LED indications on 

the mixer or power amplifier, excessive 

distortion), you can still damage the drivers 

in the Series 69 loudspeakers by overdriving 

them past their recommended amplifier 

power-handling ratings, or past the point of 

amplifier clipping. Such damage is beyond 

the scope of the warranty.

We give you two power-handling 

numbers for the Series 69 loudspeakers: 

continuous amd program. So how much 

power do you really need to drive the Series 

69 loudspeakers?

The answer to that question depends 

on what type of program material you are 

running through the system and how loud it 

needs to be.

Some audio signals have lots of 

momentary peaks whose amplitudes 

extend far above the average overall level 

of the program. Percussion instruments are a 

good example of this. Other types of signals, 

like highly compressed rock music, have 

a higher average signal level with fewer 

peaks. Speech reinforcement requires less 

power overall, but involves large moment-

to-moment variations in level.

Assuming you want to use the full 

capability of the loudspeaker, and the 

program contains at least some momentary 

peaks, we recommend that you use 

an amplifier that is rated at twice the 

continuous power rating of the loudspeaker 

(into 8 ohms). For the 6912s, this would be 

250 watts x 2 = 500 watts per channel into 

8 ohms. This insures that the amplifier can 

reproduce peaks that are 6 dB higher than 

the continuous (rms) power-handling rating 

before clipping occurs.

6912 

500 watts into 8 ohms (250 watts rms x 2)

6915 

600 watts into 8 ohms (300 watts rms x 2)

6925 

1200 watts into 8 ohms (600 watts rms x 2)

6918s  900 watts into 8 ohms (450 watts rms x 2)

Speaking of clipping, this is likely 

the number one cause of damage to 

loudspeakers. Clipping occurs when the 

signal at the output of any device in the 

system (not just the amplifier) reaches its 

maximum level. The input signal to the 

device may continue to increase, but the 

output simply stops, and is characterized by 

a “flat-top” appearance to the waveform.

Normal Sine Wave Signal 

☺

Clipped Sine Wave Signal 



Clipping interrupts the motion of the 

transducer, creating distortion and excessive 

heat in the driver, which can damage it 

over time.