Maggies...Measured Amp Power Requirements


Just how many watts does it really take to drive Maggies? Two things made me investigate this…first: on a visit to the cellar (my system’s boiler room) I noticed that the clip leds on my 600 watt CarverPro ZR1600 amps were flashing when I played the system very loud…second: I wondered if using a higher subwoofer crossover frequency would make it possible to try a tube amp for the Maggies. Some people say a good 100 – 150 watt tube amp can sound good. My Maggies are MG1.6.

With the SW crossover frequency set to 45 Hz, and the maximum measured SPL at 96 dB, I measured up to 38 vrms across the speaker terminals. This represents 361 watts, rms.

With 38 vrms measured, the peak voltage would be at least 1.5*38 which is 57 volts.
This voltage would suggest a power amp capable of 812 watts peak (briefly). So the clipping led was telling the truth.

Moving the subwoofer crossover frequency up to 100 Hz brought the maximum rms voltage down to 26 vrms. This represents 169 watts. The corresponding peak voltage would be 39 volts, and the peak power requirement would be 380 watts.

I conclude that people who use tube amps with Maggies do not play them loudly. Another factor to consider is clipping recovery characteristics of the amp. Tube amps do naturally recover better than solid state amps, so a little clipping may not be the end of the world.

I also conclude that I can forget about trying tube amps with my Maggies. Shucks. Now what will I do with all that money?
eldartford

Showing 2 responses by jafox

Was Jvogt's improvement strictly due to the increase in power or the refinements brought on in Madrigal's amplifier design between the 27.5 and the 335? What exactly improved? .... less strain, more openness, more dynamics, etc. Details here would be of great value.
Controversial indeed. Ah nuts, why didn't I think to do the same experiment with my pair of JL-3 Sigs which have been driving a pair of Maggie 3.5s until tonight when a pair of Soundlab A1s arrived. With the 3.5s sidelined I just have no desire to try the Maggie measurments but maybe when I feel bored I'll give it a shot. All I can say is that the JL-3's drive the Maggies like no amp I every experienced and oh my, so very LOUD. But I did lose a tweeter last week as I did not get to the volume control fast enough on an explosion in the Roger Waters "Amused to Death" LP. So a trip to Magnepan last week took care of that. I would love to hear a shootout of the JL-3's with the massive Pass or other megawatt SS amps.