Pros and Cons of built-in amps?

Hello again Ryder! I should qualify the previous post. I measure to 30 Hz in my room at about 2 db down. The Eidolons ($25,000 with the Walnut Burl upgrade) measured 1 db down and 3 db down at 28 Hz in the same room. Now, you know the size of the AML-1's. They use a flat piston instead of a cone for the low frequencies. The motor assembly is about the size of the piston. This is feeding into a 5 1/2 foot transmission line from the rear of the piston. You cannot visually detect the piston moving at loud listening levels! The Eidolons weighed 150 lbs, were a 3 way with an 11" woofer and a vertical port with a very complex passive crossover network and a costly cabinet. I think the AML-1's are now about $10,000 due to the falling dollar. In this context however, they are still a bargain considering you get the amplifiers, electronic crossovers, equalizers and do not need to pay for the glorified fixed frequency tone controls called speaker cable. Plus, I feel the overall performance is improved. As a bonus, my friends need not fear a hernia whenever I decide to re-arrange the listening room where I now have more square footage left over!

Hi Usarrn, I concur in that the AML-1's can be considered as a bargain for their price in that we are getting so many things in one box and still able to save money on exotic speaker cables. This can be said for other good active speakers such as ATC. The only thing that amazes me is the 6.5" flat piston woofer constructed from carbon fibre/Nomex honeycomb that enables large linear excursions down to 33Hz from those rather small boxes. And I'm surprised you managed to get 30Hz-2db! James Tanner had previously measured the response of two units of his TLE1 subwoofer in his room and he also got about 30Hz. Considering each TLE1's have dual 6.5" woofers, I think there is something special going on in that flat piston woofer of the AML-1.

Anyhow, there is the SB100 subwoofer to match the AML-1 for surround monitoring. I am using the TLE1 subwoofer for my LB1's with great effect. It's good to note that you are getting excellent bass response from the AML-1 without the employment of a subwoofer.

You know, you can get all the benefits and none of the downsides of active speakers in other ways - either an active crossover or no crossover.

The big problem with active speakers is that any one that has decent bass response is going to be shaking the crap out of its amps. That is, you know, real bad for sonics.

To Paul: What about soundwaves traveling through air or floor hitting the tubes in free standing amplifiers? I do not detect any evidence of "shaking" electronics, Doppler distortion or distortion of any kind in the PMC AML-1's. I would assume any design requires proper implementation to succeed. Audiophiles just will not give an active speaker system a chance. Could it be that it is not about the music, as they are fond of saying, but the new equipment of the month that they are so passionate about? Find a PMC dealer. Listen to a properly broken in pair. Then fairly criticize if you can.

Usarrn,

The thing is those vibration sources can be and typically are taken care of. That's why we spend money on good racks and isolation platforms.

You certainly are not going to "detect" obvious things like doppler distortion or obvious effects of vibration, but they are going to be there, as anybody who's ever experimented with vibration control will tell you. It tends to affect about everything.

Inside the speaker itself is going to be the worst source of vibration. Even moving the crossover outside of the speaker pays dividends, which is why some manufacturers do it, and now we're just talking about a few caps and coils.

There's nothing at all wrong with active speakers, but the point is they come with trade-offs, like most things in audio. They're not, IMO, a stroke of genius and not the wave of the future. All of this also assumes that you buy into the mantra that digital amps are "just fine" and amplifiers don't really having any bearing on sound quality.

If you happen to be into open baffles, it's not so easy to make them active anyway. :) Well, there's duck tape...