Dear Randy,

We've been testing the EPM-300 modules and we do not see any design issues with this amplifier. We have been producing this model for over three years without incident.

When we first heard of your problem, we honestly thought that there might be a real issue. We extensively tested many units and we were only able to make the amplifier shut down when driven to a true overload condition. I must also say that when this occurred the amplifier was in HARD clip.

We have told you in our phone conversations and direct email communication, your testing techniques are not really valid from an engineering, test, and measurement standpoint. Also, all they really seem to do is add more confusion to a fairly straight forward situation.

The problem you are having is that you are asking the amplifier to deliver output power levels well in excess of its rated power. When you do this you are forcing the amplifier into hard clip. It then shuts down. When we asked you to disable the soft limiter, we felt certain that you would be able to hear the difference in sound quality, as the limiter is no longer softening the clipped waveform. It also makes it seem a little "louder". Your response was that you could still make it shut down at "14", whatever that is.

This is what it is designed to do. It is designed to protect itself from gross overload.

I'm sorry that you are not satisfied with the output level you are achieving with this amplifier, but it is not a fault in the amplifier. It is making more than its rated power, and to reiterate, there is nothing wrong with the MPS-1.

The sad thing is that this thread and the associated comments are making people doubt a product that we have produced for a number of years. We have never had complaints of this nature until this last week or so. In both of these instances, it appears the amplifiers are being driven in a manner outside of their design limits.

They are dong EXACTLY what they were designed to do. Some users do not notice hard clipping or signs of overload, these protection circuits are designed to protect both the amplifier and the speaker.

We take great pride in our products and we want you to be 100% satisfied with your unit. As we have told you many times in the past, if you wish to return the unit, please asked for an RMA and we will arrange this for you immediately. You will be give a prompt refund.

Randy, you need at least twice the power of the MPS-1 in order to realize a meaningful increase in SPL. I have no idea why you want to drive your system to these levels but this is your decision. Please use hearing protection; BTW, I'm not kidding!

Respectfully,
Dan

Dan Laufman