I am assembling a tri-amped system using six M200's. I have not finished building my speakers yet, so I am using some cheap test speakers to test my electronics.

When I power my system on or off, a transient is generated which causes an audible "thump" from each of the drivers in the system. I am very concerned that when I attach my (expensive) new tweeters in my finished speakers, I will damage them.

What do you recommend? Is there a commercial product which includes a couple channels of muted amplifier protection? Rack mount is preferred.

I could wire up a box with some beefy switches in it, but I am afraid that at some point, someone will forget to open these switches before a power-cycle.

First of all, I would strongly recommend against using any amplifier as powerful as the M200 for tweeters. These drivers need much less power than the midrange and woofer drivers. The ideal power level is 1/2 to 1/4 of the power of the woofer amplifier.

The trainsients you hear could either be generated by the power amplifier or the active crossover network. In my system, the active crossover generates a turn-off thump so I designed a timer which keeps the crossover powered on for a minute or so after the power amplifier turns off. This eliminates the thump since I use vacuum tube power amplifiers which still pass signal for several seconds after power is removed.

Some power strips include timing functions in addition to power line filtering. Other members might have some specific brands

I would dis-connect your crossover from the power amplifiers and cycle the power to see if the cause is the crossover or power amplifier.

If it is the power amplifier, a method I have used in the past has been to place a non-polar capacitor of high qualiy in series with the tweeter's "hot" lead, and choose the value of the capicitor so that the cutoff frequency is between 1/4 to 1/2 below the crossover frequency of the active crossover to the tweeter. For instance, if you use a 2kHz crossover to the tweeter, choose a capacitor that causes a high pass frequency of betwen 500Hz and 1kHz.

This high pass capacitor will keep low frequency information generated by a power amplifier transient from reaching the tweeter. The high frequency transient information that remains is unlikely to do any damage to a tweeter.

Soundhound -

Thank you for the response. I did an experiment in which I switched the amps into "music-mode" and power-cycled only the amplifiers - the transient is substantially reduced.

Is the amp output muted in the "music" mode or the 12V remote mode? Would it make any sense to strap the amps into 12V remote control mode, and wire up a delay circuit to attempt to power-cycle the amps at the appropriate time?

I have no idea about this as I don't own Outlaw amps, but rather vacuum tube ones. I do however use the 12 volt trigger output of my 950 preamp to turn on my whole system via a relay box I built.