I started an ill fated audio company back in the 90's called Bottom Octave Audio Specialties... it was fun while it lasted. A subwoofer adds a sense of surround and realism that brings the sound to another level. If done properly even the highs seem to take a new level of detail and brilliance. Once you go deep you wont ever want to go without... just keep it tight and controlled without drowning out the midbass... it has to smoothly blend with the midbass to sound perfect.

No sub woofers... Get one... OR TWO... use them for a month, then remove them... See how long it is before you put them back... No sub, I can't imagine not having them...

Passive radiators are used a lot in smaller Bluetooth speakers where they can do a pretty good job. I own a Denon Envaya which is very capable for its size. It has a big radiator at the back which helps a lot in the bass department. So, if well engineered, it can be very helpful!

Paul, every video is a winner. Your authenticity is compelling. Well done.

One of the things seldom talked about is that by using a regular speaker driver with a voice coil and magnet as your passive radiator you can control frequency response, damping, and transient response by connecting passive components to the input terminals of the passive radiator.

A good saying says...if two always agree on everything one of them is not thinking.

My Sunfire XTEQ 12 has a radiator. Nice little sub and it chucks out some decent thump.

"Yeees!"...that´s the sauce ;) Love your points of view. Many thanks from Portugal.

...watch my language, says "fart". Part to the reason I love the videos is because Paul is such a chilled, friendly guy, radiates calm. Would be amazing to work for him.

Ahhh...Passive Radiators...I remember the days! I still have my Kennwood LS-9000HG's that had 18" Passive Radiators. I bought the pair in 1988 when I was stationed in Okinawa Japan. Sadly, the surround on the radiators and the woofers have long since dried out and crumbled. Not sure about the tweeters as I haven't attempted to play them since sometime in the mid-1990's. I keep them because some day I want to refurbish them or restore them. These were the best floor standing speakers I have ever owned.

I have made speaker boxes with passive radiator and with the correct baffle placement inside the box you can get huge benefits to tonal richness and bass that said you can't beat a good pair of sealed speakers and some well balanced Subs

My speakers have two 4" ports in 5½ cu. ft. enclosures (6 cu. ft. minus ½ for midrange sub-chamber). They are tuned to below the driver resonance, to extend roll-off. There is no audible farting or chuffing. I can hold a match to a port, and even on low notes, it flickers slightly but does not go out. The ports are longer than the original JBL 4343 design indicated. They are PVC pipe, and have an elbow to get sufficient length. I was able to borrow an HP wave analyzer to empirically determine the length. I used a binary search, and wound up with scrap PVC. :) It was a fun project that I have enjoyed for decades.

If manufacturers started putting rudimentary tone controls on their preamps and/or integrateds it would go a long way toward eliminating the perfect speaker goose chase. Treble, bass, loudness boost can do a lot of the heavy lifting.

I have been working with passive radiators with my loudspeakers and subwoofers for years, and love the clean punchy bass they produse. But I must correct you and what many others claime. 1st a passive radiator is not out of phase, the backside of the driver is out of phase inside the box. But when the pressure in the box moves from the driver to the passive radiator, it use some time and the phase shifts 180degrees. So both the passive radiator and the driver moves in and out at the same time. 2nd It may have many simularities with a port, but a cone or membrane makes soundwaves in a much cleaner and linear way. VS a port that makes soundwaves that probably looks more like rings of smoke. And thats far from an optimal way to make sound vs a membrane that makes clean soundwaves like the driver. So with a paasive radiator you get to use all the pressure in the box to make a clean wave in phase with the driver

I have built systems using "passive radiators" to great effect, lowering the drivers Fs, increasing efficiency, & output levels. They are much more useful than a second driver installed in the same enclosure, doubly so for a poorly designed port opening, which is a more common problem than most will admit to.

I think only one drawback of passive radiators is that they make speaker to vibrate much more due to increased moving mass. But in my opinion they sound much better than ports and you can make box size same as sealed one and have more bass without port noise. In some cases they can be even cheaper than ports.

Sprout speaker??? It’s the first I have heard about that one. I bought my Sprout & a set of Bookshelf ELAC B6.2 speakers. I would enjoy hearing about what your plans are.

I love subwoofers (sealed) ... But the biggest problem is setting up... My favorite configuration being the main speakers running in full range (sealed ones) then having the sub extend the low end with a bessel allignment.

Is there any benefit in modifying ported bookshelf speaker to passive radiator? And what would it do to the response? Im talking about Boston Acoustic A26, its a budget bookshelf with 6inch woofer.

I agree subwoofers are great for other speakers but my three way monitor audio speakers go down to 27hz and the bass on some records actually rattled the glasses in the kitchen the other day.

The way I see it, passives are a compromise between sealed and ported. I don't like when the passive faces the same direction as the sub, but I understand when the phase cancellation is deliberate and calculated.

With today's equipment, whether it be low to mid end and even high end, you NEED a subwoofer. Unless your room is able to support low bass from a three way speaker that has extension to at least 25hz. Even then, that's debatable depending on the type of music you listen to...it takes allot of time to get a sub to integrate with your system and I think it turns some hobbiests off...

Passive radiators seems to be used more often in compact or in-wall speakers.

Passive radiator is using 1 voice coil to drive 2 speakers usually of different sizes to more efficiently have a wider frequency range.

Passive radiators are very popular in small Bluetooth speakers nowadays. The alternative of using a tiny bass port will yield too much wind noise.

I love your lectures Paul, but I have to comment, Radiators don't produce steam, they condense it. Boilers produce steam, and to a more accurate description, they produce high temperature water pressure. The problem with steam is that it condenses the instant it falls below "steam conditions" which vary depending upon atmospheric pressure and temperature, and system pressure and temperature. Most laypersons think that steam is a constant, but that couldn't be farther from the truth. Water vapor is even more unstable than water ;)

ok, so a passive radiator will give you more bass. butt....what effect will it have on the sound due to it being out of phase?

I still own a pair of Celestion Ditton 25's and to my ears the use of a passive radiator was designed right by those oldschool engineers. My son wants them when I go deaf but he'll need to wait ...

Press Release: "SproutSpeaker" @ 5:24

Thanks for the explanation. I had some knowledge about passive radiators, but never had the thought of imagining it as a port. I feel kind of stupid now, haha.

I dont think much of subs ether lol. Celestion Ditton 15 have a radiator with woofer & tweeter , deep base line these have , but treble not so good . take a look . good for R& B base line .

subs all the way!

Subs are great if you want lots of bass at the expense of large amounts of THD/IMD. Paul Klipsch believed sub woofers were inherently bad for that very reason and I honestly tend to agree with him. Big high excursion drivers flapping around creates just that very thing and it stands to reason that anyone who truly cares about quality sound would want to avoid that. Utilizing a horn on the other hand can produce incredible low frequencies without all the distortion. When you essentially turn said woofers into a large compression driver you eliminate the vast majority of the added cone distortion which with subs is measurable and substantial. IM distortion being particularly obtrusive, you want to eliminate as much as possible. If you care about quality bass over quantity of bass then horn loaded LF bins and horn loaded subs are really the only way to go. Anyone who has heard the difference between horn loaded bass vs. direct radiator systems knows the difference is undeniable. So yes subs aren’t of particular help unless they’re the right subs which are not the subs McGowen advocates. Speaking of passive radiators, Klipsch is yet again a company who utilizes said technology very well. In fact their passive systems are second only to their fully horn loaded systems in my experience. Talk about some smooth bass with no immediate need for a subwoofer. Yes it is out of phase on most models which can make them a bit finicky when it comes to placement but I’ve never found it to be a major issue. Sorry for more of my Klipsch fanboy rants but it just baffles me how so many people claiming to be all about high end audio continue to ignore and or deny just how substantial Paul Klipsch’s contributions to the world of quality sound reproduction truly are. Not only when it comes to speakers but amplifier development as well. Anyway end of rant. I know I probably shouldn’t even be wasting my time, or anyone else’s for that matter, ranting on four year old videos but some of these remarks deserve a factual rebuttal.

This is off topic, but maybe someone will answer. We all know running lower impedance loads than recommended is bad for your amp and speakers possibly, but why? Suppose I had a 2000w amp @ 4Ω and I connected a 2Ω load? Would it damage the amp at low volume or would I have to increase the gain until it was pushing more than rated power?

how to powered 12 0 12 volt supply by car battery...??is it possible...!!

I hear chuffing here alright. REL SUBS passive radiators. Nuffsaid!

I think ports are just a way to have a Smaller Cabinet . Save space add a Tuned port. Got room make a big box.

Paul, Steak Eating audiophile here. What other systems use an Active Passive radiator, AKA Acoustic Coupler IE: Vandersteen Model 2?

Yeah subs are crucial to audio. Full range

Passive radiators where the kind we had in the very cold house in which I was raised.

I don't like subwoofers either. Don't need it. About 40 years ago I had a set of EV 3 way 12" speakers . The voice coil burned out on one them so I removed it. A friend wanted it so I gave it to him. A couple days later he brought a cabinet with the bad driver in it. He removed the voice coil and called it a drone. It was not what I expected but that system sounded pretty good. We were in our mid teens then and were building our own speaker systems then buying the drivers and making our own cabinets.

I have only heard cheap mass produced passive radiator speakers that boomed and sounded unnatural. Anyone know of a good high end speaker with passive radiators?

this is why i like vintage gear. 12" woofers was the norm. my jbl's use a 14". subs need not apply

I don't believe he disagreed with having a subwoofer but something else like the line connection or something else. He might have real full range speakers.

They always talk about cabinet rigidity ..then they put a hole with a passive rubber moved by the air moved by the active driver...i dont get it...when the active drivers pushes air forward the silly rubber goes back and vice versa sucking power and impact ...mmmm they say it helps make better more punchy bass..mmm dont think so...that fuckin rubber is out of phase moving all way around what the actual woofer is doing..please explain further...i see lots of passive radiators on portable bluetooth speakers and they seem to work..but it doesnt make any sense to me...i need further explanation on whats going on..thanks

Paul.... if you are such a believer in subwoofers why then do I not see such a thing ( or things..! ) next to the IRS V's ...??? Mmmmm...? Lol !! Ports only fart if they are too small in diameter ( and not flared at each end ) the object of good port design is to achieve what is known as " Linear port airflow " this only happens when the port is at least 1/4 to 1/3 of the cone area. The beauty of a PR is that you achieve max possible port area ( similar to the main driver ) but without the inordinate long port length that you'd have to use if it was just an open duct .

TBH, I don't see the point of a separate subwoofer if a stereo speaker already has 3 or more pairs of amps and the largest driver already has the ability to produce sub bass frequencies well down to 20Hz or lower. That said, most speakers can't go low enough, hence the need for a sub woofer.

Maybe handheld Bluetooth speakers use something similar.

NO! Please don't say that ports or passive radiators are out of phase EVER AGAIN! Do some research on ports and passive radiators and you'll figure out how insanely clever these inventions actually are and how they manage to produce sound that's in phase with that of the speaker cone.

the flat at the cone the more lower the bass and more air can be push. Is it really Paul a hole is cheaper !!!!!! 😉

So Harbeth Monitor 40.2 Loudspeaker are low cost, cheapie speakers because they have ports? OK, good to know. ;^)

I do not need a sub woofer in my main audio system . My Von Schwerkert audio speakers have PLEANTY!!! of Bass. I do have a sub woofer in my surround sound system.

Dear James, you guys are in the dark ages where you live when it comes to subwoofer technology. Don't judge them based on what you've experienced.

Subwoofers are essential...

Oh no! The subwoofer rears it's ugly head... again. Just kidding! I don't presently have a pair (if I did have subs, I would have two.) As Paul has said many times the key is to make sure they are properly 'tuned' (I guess that's the proper term.) That's exactly what keeps me away from subs. The thought of spending thousands of dollars and not being able to 'tune' them or (use) them properly. The manufacture can 'show' me how, but that doesn't guarantee that I'll be able to do it correctly and I doubt that Paul or a rep from the sub manufacture is going stop by my house and do it for me. At this point, I still haven't made-up my mind on buying a pair or not. Kinda in limbo...….