Who makes an active speaker that isn't ported?

ATC Makes sealed 3 way active designs

Why?

Please explain - what is active speaker?
Thank you.

Timf - To go along with a dose of subjectivity, I believe there is science to support the theory that a sealed enclosure will produce a more accurate bass response than a ported design.

Zoya - An active speaker is one that is not passive. Just kidding! ;-) An active speaker design is one that contains its own onboard amp, similiar to powered subwoofer. Each driver is supplied with a predetermined amount of power (i.e. 50 watts for the tweeter, 100 watts for the midrange and 150 watts for the woofer). This design eliminates the need for XO's and thereby fixes many of the issues surrounding bad XO design, which introduce distortion and other undesirable effects. By supplying each driver with its own dedicated amp, speakers that are active tend to have a less colored more accurate sound. Think of it as a properly aged wine - richer, fuller, smoother etc. Many believe this type of design would be more popular if it wasn't for the penchant of most audiophiles to continuously tweak their upstream components.

"This design eliminates the need for [PASSIVE] XO's."

Active equalization is almost always incorporated in the design of an active system. But I am in total accord on getting rid of those nasty inductors. We worry and kvetch over speaker cabling, but disregard the yards and yards of wire in the inductor of nearly every speaker extant. The subject has been well-hashed in the archives.

On ported vs. sealed enclosures. This debate is closing in on the vinyl vs. digital and tube/SS wars. I would think both designs are valid, thought not without a sonic signature attributable to both. That said, we seem to get caught up listening to the technology instead of the music. Maybe it's just me, but I recently discovered [with the kind help of a fellow Audiogoner] that I have pretty good gear, good enough to stop fretting over its quality. The point of the game is to Enjoy the Music. So I bought lots of music at my local HiFi Hut, and I could not be happier. This revelation came admittedly late in the game, about 25 years worth. But I learned the lesson and now I really enjoy my tunes, and still admire the hardware that gets me there. I wish you and all lovers of music the same. Good luck in your quest. *Sorry for veering off-thread but it seemed relevant.*

Dawgbyte sez:

This design eliminates the need for XO's...

No, no! You ALWAYS need filtering with a multidriver spkr system. It's just that the XO can be placed before the amp(s), each amp unit thereby connected directly to a driver & amplifying only part of the spectrum.
And since it's at line level, the signal is low and there is less distortion induced than with regular passive spkrs, and there is better control. Also, amps work effortlessly, amplifying only a few octaves AND driving the driver voice coil directly. Cheers

Gregm - you're correct there are XO's in active speakers. What I meant to say is... well, precisely what you pointed out. My mistake.

Cinematic Systems... I thought ATC's were ported in the front. What multi-driver model is not ported?

The ports are not a bass alignment, they are to release pressure from the cabinet under high SPL conditions, same with the Meyer Sound reference monitors.

So they are ported but not to extend bass frequencies.

For whatever it is worth, the best vehicle sound I have ever heard is with a six speaker system (Infinity) with ten watt amps with each speaker.

ports are not a bass alignment, they are to release pressure from the cabinet

Are you saying the ports don't contribute to the/any sound? Do you know anything about this? If so, care to expand? Cheers

Cinematic_systems is a ATC dealer.
I will disclose this for him as a favor :~)

DB,

One more name to your list (a name who has perhaps been a pioneer in this active loudspeaker technique):
Boothroyd-Stuart Meridian's DSP8000

AFAIK, this active speaker is a sealed box (atleast reading the info posted on their website)
http://www.meridian-audio.com/p_d8k.htm

"ports are not a bass alignment, they are to release pressure from the cabinet"

"Are you saying the ports don't contribute to the/any sound? Do you know anything about this? If so, care to expand? Cheers"

Well, I'm repeating what i've been told, the cabinets are designed in such a way that they maintain a particular impedance, the holes on the cabinet are the visible mechanism from which the air is released, but there is a matrix which leads to a cavity that is then ported. Any sound coming from the port is unintentional. You will not feel air chuffing out of the ports due to bass and measuring the speakers you will see that they have a 2nd order rolloff not a 4th order like a ported system.

In both cases Meyersound and ATC, neither are in a huge hurry to talk much about the cabinet design internally.

Bambaywalla - thanks for the FYI. I've seen, but not heard the Meridian DSP8000 speakers. Given what I've read on this board, I'm a little skeptical about 6 outwardly facing woofers. Why so many and why place them in that particular arrangement? The air pressure and vibration potential must be addressed in a very clever way I would think, or they would fall flat on their face.

Like I said, I haven't heard them... they could be incredible.

"I'm trying to think of a 3-way active speaker that isn't ported... "

How about the Linkwitz Orions...3 way, active & no ports...no cabinets either :-) .

Orions

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