Cost aside…Yes, they have a con.
They are more expensive.
Well designed both works, but a passive is more expensive.
Cost aside…
There are passive monitors like the Focal Shape 50 that are in the same price category as other ported monitors.
Same with the Amphion One15
Passive radiators are always technicaly worse than good slot-ported or port designs.
The distortion is higher with passive radiators. The only advantage is that you can shrink the cabinet and get the same -3 dB point in the bass , compared to a ported design.
This is a serious salespoint in a store, more important than really good sound.
The price for shrinking the cabinet and using a passive radiator are always: higher distortion and somewhat unarticulated bass, compared to good closed boxes and ported ones.
In 2022 you see a lot of designs with passive radiators from lots of companies.
I always stay away from those.
In a minimal phase system like a woofer the group delay is a function of the highpass frequency response, meaning if you tune it to the same response it will have the same GR independently from if its closed, ported etc. There is a good article about it here.I wonder about passive/ported vs infinite baffle/closed and effect on group delay at LF.
Do the latter have an advantage due to lesser group delay?
Does GD matter… are there known thresholds of group delay where yes, it does start to matter?
Ok thanks, this surprises me as I had though GD increased with stored enclosure energy, such as mass of air in ports or passive radiators. I will do the reading !meaning if you tune it to the same response it will have the same GR independently from if its closed, ported etc.
Shouldn’t the room also be included in this? It will reek havoc with the frequency response and consequently group delay.In a minimal phase system like a woofer the group delay is a function of the highpass frequency response, meaning if you tune it to the same response it will have the same GR independently from if its closed, ported etc. There is a good article about it here.
Not an issue with a good designed port. In many cases the ports are to small though.Port compression is often not included in these kinds of conversations. I wonder why…
There are some truly great passive radiator speakers out now.The only advantage is that you can shrink the cabinet and get the same -3 dB point in the bass , compared to a ported design.
This is a serious salespoint in a store, more important than really good sound.
The price for shrinking the cabinet and using a passive radiator are always: higher distortion and somewhat unarticulated bass, compared to good closed boxes and ported ones.
In 2022 you see a lot of designs with passive radiators from lots of companies.
I always stay away from those.
Not an issue with a good designed port. In many cases the ports are to small though.
Passive radiators are unlinear just like ordinary drivers depending on how loud the music plays.
As I wrote before - a passive radiator construction are mainly a salespoint because the boxes can be smaller for the same amount of bass , but the quality will suffer.
If you want to make a passive radiator construction less bad, you must have a steep HP filter just below the tuning point otherwise there is no damping of the cone at all. This is done in some of RELs subwoofers . The same can be done in all ported designs with a dsp , like Genelec does in its SAM monitors.
2x SD is not an issue since you would want one woofer and one waveguided tweeter of similar size at the front. So the back is more less available for 2x SD.The cabinet volume difference isn’t really that much. Usually it’s about the same as a reflex alignment. Reflex just adds the port volume. What you do need though, is more surface area. You needs at least a passive radiator with twice the SD of the active driver, preferably 3x. All these PR’s need to go somewhere..
Ports have their own issues. For a smaller speaker, a large enough port is mostly fine. For low tuning, a port can quickly be very long and large. Taking up considerable volume and are prone to resonances. In those cases a few massive PR’s can really work very well.
You have a very good point in this . Most PRs are wrongly constructed, focusing only on the salespoints with smaller boxes, with a single and to small PR . And as I wrote earlier, a PR construction need a steep HP filter right below tuningpoint.You needs at least a passive radiator with twice the SD of the active driver, preferably 3x. All these PR’s need to go somewhere..
You have a very good point in this . Most PRs are wrongly constructed, focusing only on the salespoints with smaller boxes, with a single and to small PR . And as I wrote earlier, a PR construction need a steep HP filter right below tuningpoint.
As for subwoofers - I would buy a Linkwitz transformed closed box with a low Q driver any day of the week .
We don't see that a lot though, especially not on cheaper designs. Who wants to hide apparent woofers?2x SD is not an issue since you would want one woofer and one waveguided tweeter of similar size at the front. So the back is more less available for 2x SD.
It is in many cases. Moreover, if you take a tower enclosure, and shove 1 driver and 2 PR's in it, it will look impressive, and also, you can actually use a cheaper driver with a relatively weak motor and larger VAS, since you'll use the whole tower volume for the single woofer, vs a tower that has to share the volume with two drivers and some ports. Obviously the same goes for a single driver + port, but the PR version will probably sell much better because it looks more impressive.It’s just the cost imo, that’s the only negative.