Logitech backward firing speakers 360

obobski

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looks like a passive radiator over an active driver, but either way, it'll be fairly similar (in concept) to the myriad of omni/bi directionals released over the last 10-15 years

basically: placement is 110% of the game, if you don't set it up right, it doesn't sound right

the rub is of course that these speakers are a "marvel" of what you can do with ABS (not that you should, of course), so the sound quality probably isn't very great overall (in other words, I wouldn't expect very much at the price these are being offered at)
 

Sycraft

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Looks like a passive radiator. The idea here is to increase bass response, it is the same general thing as a port in a speaker. As for back vs front, doesn't really matter so long as the speaker is designed right. Bass is extremely non-directional as the waves are quite long. I've had speakers both ways and they sound the same. My 604s had a single port in the front, my MTS-01s have two ports in the rear.

There are various formulas to calculate the proper placement of a port, or radiator, given the size and design of the speakers. So long as they are followed, there's no problem. Front, rear, side, they all can work.
 

PM650

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Passive radiators aren't used in bass reflex (ported) systems, it's likely an active driver for a bipolar or dipolar setup, depending on how they're wired.
The terms bipolar and dipolar both refer to speakers with drivers that are fired in two different directions. With dipolar speakers, the two sets of drivers are on the sides of the speaker aimed in opposite directions and are in reverse phase causing a cancellation of sound waves in front of the speaker. This is usually done in rear speakers that are mounted on the wall, where the front of the speaker is aimed at the listening area. This causes all of the sound to bounce off the walls before it is heard. This makes it almost impossible to determine where the speaker is, causing a true surround sound effect. With bipolar speakers, the drivers are fired in opposite directions, but are in phase causing an increase in bass output. In this case, the drivers are in the front and back of the speaker.
 

Sycraft

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I just looked at the second link provided, those aren't a ported design. I didn't realize they were two active speakers.

You are correct that these are bipole or dipole speakers. That said, doesn't seem like a terribly good idea for front speakers. Normally you want dipoles right to your sides, as they tend to produce non directional sound. Having them in front risks getting interference waves from whatever bounces off the wall. You would probably end up with a more ragged frequency response than a standard speaker.
 

obobski

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Passive radiators aren't used in bass reflex (ported) systems, it's likely an active driver for a bipolar or dipolar setup, depending on how they're wired.

I so hope you're wrong, because if they really put a pair of drivers back-to-back and wired it up, probably in series no less, ugh :eek:

I just looked at the second link provided, those aren't a ported design. I didn't realize they were two active speakers.

You are correct that these are bipole or dipole speakers. That said, doesn't seem like a terribly good idea for front speakers. Normally you want dipoles right to your sides, as they tend to produce non directional sound. Having them in front risks getting interference waves from whatever bounces off the wall. You would probably end up with a more ragged frequency response than a standard speaker.

eh, I've seen bi/dipoles as front mains work out fairly well, most Logans are technically dipoles, and can sound fairly good if you position them right, most Definitives are either bi or dipoles, and most older Mirage speakers are one of those (They've since moved to an "omnipolar" solution, similar to B&O (and it sounds about 50x better at about 1/10th the price ;)))

like I said, placement is king here, don't put 'em out right, and they don't sound right (ever heard Logans placed up against a glass wall? not pretty)
 

PM650

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I just looked at the second link provided, those aren't a ported design. I didn't realize they were two active speakers.

Looks to me like they moved the ports to the rear of the speakers in the 2nd link (small slot vent).

I so hope you're wrong, because if they really put a pair of drivers back-to-back and wired it up, probably in series no less, ugh :eek:
I'm quite sure that I'm not wrong :)D), but I was referring to wiring wrt to phasing - series & parallel are both possible for in or out of phase operation, though I assume parallel is more likely for obvious reasons. Tbh, I wouldn't expect production variation to be significant enough to negate series use (providing the two drivers in each speaker are from the same run) - all depends on what impedance they are & what the amp will handle I guess.
 
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