Removing the main speaker's woofer work

[@Anh-Áo-Nâu]

Paul, just got your end of 2024 sale preamp last week. Solid build and great sound. Thanks

[@Koolbob2]

Over 20-years ago I was installing and setting up our surround system in the living room of our new home. The equipment at the time was a Sony ES series 5.1 receiver, Paradigm Cinema 90 bookshelf, center and surround speakers and a Hsu VTF sub. I ran the Sony room correction setup with the included microphone and was very underwhelmed with the results. I started poking around in the setup options and switched the main speakers from 'small' to 'large' and the sound improved dramatically, even though the woofers in all of the speakers were only about 5".

[@BobGeogeo]

"I lost my low bass back in Oregon, don't take me alive..." Sort of Steely Dan.

[@turboboost99]

Yes, absolutely roll off the lowest octave -- and then use subwoofers that are properly placed in order to hear the bass that the main speakers are now relieved of producing. That's so obvious I don't know why Paul didn't mention it.

[@tomday7309]

I was told many years ago that even if you can't directly hear frequencies too low or too high for your ears, the speakers ability to reproduce them along with your hearing range will add depth to the sound coming out of them because of the higher range of octaves reproduced. That may be BS, but it seemed reasonable to me, a vintage guy with vintage equipment.

[@davidkclayton]

Apparently Paul likes Doppler distortion

[@bikdav]

What is Doppler distortion?

[@davidkclayton]

@@bikdav here's some quick information on what Doppler is. en.wikipedia.org/wiki/Doppler_effect Now visualize a speaker cone moving to its X Max to produce a low frequency and a higher frequency at the same time.

[@janinapalmer8368]

Change the room ... don't mess with the speakers

[@Joshualbm]

So, the other way around this is using a pair of subwoofers and rolling off the mains with a traditional active or DSP crossover. But I know this flies in the face of your preference to use speaker level sub inputs. But the problem is solvable by having that lower octave dealt with by sub room placement. It's often the case where setting up the main speakers for the best imaging etc isn't always the best for bass. Pro audio sound technicians deal with this all the time. Is the "sound" of your main amp really that important to try and retain at 40Hz and lower? Or is the time arrival the issue between line level and speaker level? Because that can always be dealt with by phase control, correct? Also, the main amp will be relieved of needing to use all the current for bass that isn't really being implemented well.

[@Jorge-Fernandez-Lopez]

The phasing issue remains (no relation with phase knob or position). That's how equalization (DSP o analogue) works, except the alternative (DSP or arnalogue) that creates pre-ringing that sounds even worse.

[@ThinkingBetter]

Perhaps the question also pertains to bass that is lower than being audible (

[@Jorge-Fernandez-Lopez]

I checked all my music, almost nothing under 30 Hz (enough resolution of the analyzer must be selected) with enough energy. I have used tones (very carefully) to solve standing waves problems. However, music is not a tone. Good speakers should handle very low frequencies with a controlled roll-off (acoustic-mechanic high pass filter) rate.

[@markfurlonger9356]

Great videos. You also have the problem that each listeners room will have different characteristics. Limiting the range will impact folks differently.

[@Jack96993]

My main speakers have built-in powered subs I also have 2 powered subs with DSP Im thinking its like a bass array setup After I dialed in my listening room and integrated my subs with the mains, I'm in full range music heaven 😅

[@johndough8115]

Id love to see an experiment, using several woofers, and several other drivers... where you split the frequencies up, using FAR more Crossover points... to vastly reduce the workload per driver. This would make for far less potentials of Micro-Distortions, due to each driver having less overall work to perform (in that particular frequency band). I noticed, that when I was using my 5.1 Surround Sound Amp with 4 speakers, and switching to 5 (center speaker).... that the front Left and Right channels, were MUCH cleaner and clearer. The mere act of removing the additional vocals (and any other center content) from the front-side speakers, gave such an amazing impact to how much better the output was, from those speakers. At that time, I didnt know enough about speakers, to really understand why that was happening. That said... at that time, I wasnt using Audiophile grade speakers, either... So, Im not sure if it would make as big of an Impact, if all drivers are Audiophile grade (superior magnetic strength drivers). Finally... Im not so certain, that changing your Demo room, is the right thing to do... As showing them off in a room that is "Standard" to most peoples homes, is how most people would experience them. That said, you might be able to make an "Expanding Back Wall", for example... So that you can slide the back walls, and change the room shape, so that people can experience Both. Heck, if you wanted to go All-Out... you could also make side-panels on the side-walls, that Rotate... from a Flat Surface, to a Surface that was Treated with Foam or other Absorbing materials. That would, of course, take a bit of tricky Construction... but it could theoretically be accomplished.

[@sudd3660]

do no think many way speaker is a solution, there are single fullrange drivers that does impressive work. we are talking about stereo here. we also have the value for the cost aspect that make multi way speakers not compete. i have my finger on 3 way for a nice compromise.

[@johndough8115]

@@sudd3660 Fullrange drivers, are total Crap, compared to even decent 2-way speakers. I also have a pair of low-end 3-way speakers, that are utterly Destroyed by my Audiophile grade 2-way speakers ( EPI 100v ). So, its not Just about the number of drivers.. but also, about the Quality of the drivers. But as said... Its a proven thing, that you Can in fact, get better audio performance, by splitting up the workload. Such a process, can actually make low spec drivers, perform close to high end drivers. As far as costs goes... Lets be real here. Most Audiophile grade speakers, are Insanely Over-Priced. They might use $40 high-end woofers... but, they will charge you the equivalent of +$500 per each driver. They are charging you for small batch runs, and higher end cabinet finishing (trying to make a Mirror Finish, without any blemishes, via hand-work, rather than automated machines). My 70s era EPI 100v speakers, use drivers that outperform the local high end stereo shops $3000 flagship tower speakers. Its not even Close. When they originally sold, I believe they cost under $300 a pair. Not sure what inflation would put that at... but certainly much cheaper than the kinds of speaker prices, that you see today. Anyway... Im speaking about the cleanest, distortion free, potential Output (at any volume level). It does not matter, if anyone could or could not afford it. But I guarantee, you could easily make such speakers, affordable. The problem is, low number runs, drive up costs considerable... and since companies do not provide enough education to the public about whats different "Inside" of the speakers... they dont know the differences, between the Low Spec speakers, and High Spec speakers... from a mere External View point. This is ultimately what Destroyed most of the High End speakers, in the 80s.

[@PSA78]

There's tradeoffs with that as well, each driver needs to meet the next perfectly with response and phase (which is difficult enough with a few drivers and their crossover). There's a good reason why a small group use a single wide band, there's also a good reason why 3 way (plus subwoofer(s)) is quite common, while more is less common.

[@franny231123DMT]

word. cheers , Paul

[@ianbigsand7]

Maybe I have a fundamental lack of understanding here. Does the inaudible bass, and therefore driver excursion, not cause a doppler type of distortion? The microphone diaphragm excursion is very small compared to that of speaker cones. I once read that an advantage of horn loading is that the driver excursion is far more limited for the same spl, and that the doppler distortion is rather less.

[@sudd3660]

driver excursion is a source of distortion, mechanically and acoustically and i think the solution is adding total cone area, more woofers preferably. a horn is so large that you could for many woofer in same space to i rather do that.

[@ianbigsand7]

​@sudd3660 everything is a compromise

[@sudd3660]

@@ianbigsand7 that is not an argument. my points is that more drivers is better than horn bass, for a larger band of frequencies. you have to acknowledge that one driver doing more work is not preferable for the bass.

[@ianbigsand7]

@sudd3660 yes, I see what you mean, so long as you limit the upper frequencies fed to the bass drivers so that you don't start to have vertical dispersion/time alignment issues when you hand over to the next driver, so I suppose that this implies at least a three way system. I am just thinking out aloud, and my understanding is not that of an expert in the field, I'm just trying to understand better.

[@TheDanEdwards]

All transducers will have issues with doppler effects. It's inevitable and is one reason why sound reproduction never really duplicates an original performance from real instruments. I do agree with you that less excursion is better and that is accomplished by increasing the area of the transducer, but that brings in other issues.

[@stevenholquin2127]

Another Lip Smacking ASMR Audio Vignette From Paul In 1976 I Too lost My Bass Frequencies and My Birthday 🎂 😂 For Crying Out Loud Thinking Never To Come Back To The Full Grander of The Past….😮 Yet In 1996 I Got My Birthday Back and My Low Frequencies with a Pair of Apogee 18” Sub Woofers and Two QSC 8001 Power Amps and a BSS Digital Cross Over From This Point On I Have Never Been Without Want of Bass Frequencies In My Home Audio Set Up This Is Not Audio File Madness or The For The Weak Hearted This is Real Not Fantasy Land Plus Oddly Enough I I Can Shake The House With These Apogees ….Thanks Paul For Yet Another Fantastic Lullaby Performance As I Slip into a Piano Concerto of Erik Sati “”Je Te Veux “”

[@KevlarCondom]

Technically, 20hz is around 56ft of wave... 5hz is about 225ft of wave. you need a huge amount of speaker area to make those waves, or a very very long room. eventually, at enough distance in a room, a 2in driver will make a 5hz wave.

[@sudd3660]

you do not need to make the full length wave. you only need to reproduce the pressure so your ear can move in and out in a sine wave motion.

[@Mikexception]

The problem is very low power with which membrane is loaded at very low frequency. . Without strong electromechanical damping (usualy secured by amplifier) speaker works was spring - spring to oscillate do not need even active power. the same speaker driver. Active power is not transferred to speaker even when we observe jumps and may think it is amplifier hard job. . . Second reason is that single membrane (even with strongest damping) cooperates only with tiny and very light freely moving air layer which touches it and follows membrane movement. Mass of air must have enough inertia to stay in place and be late when membrane moves up and back. Thanks to this inertia membrane can create pressure ups and downs. For sopranos we need much less mass of air because speed of membrane is much faster and even small amount of air cannot effectively follow in time . . For low frequency when is no adequate mass of air no plus and minus pressure could be found and it means no sound. When is little mass and slow motion, air follows membrane as siame tweens. We use artificial acoustic systems like boxes. horns , we add mass with tunnnels and TL to force more air to cooperate with membrane. .

[@sudd3660]

i am asking you, please design a speaker that rolls of in the bass, give the larger models some mid bass punch, but make more small box sealed designs. design the woofers in the speaker more like a midrange than full range. and for rolling off the speakers, gr research talks about a line filter you put before the power amp, so the amp does also does not produce the bass. i like the idea of that if you do not have dsp.

[@PSA78]

You can still get a phase problem with low level filter (and the quality might impact SQ everywhere), but it is a thing to use "subsonic filter" (at least as protection) and if it's low enough it might not impact most music that don't go very low.

[@Jorge-Fernandez-Lopez]

Good speakers have already an acoustic and mechanic high pass filter with enough rate.. GR Research only put a capacitor in a box, which creates phasing issues.

[@sudd3660]

@@PSA78 you are correct, maybe a combination of the two means of subsonic filter is the least compromised option. i am not an authority on high end audio so i get excellent results from dsp solution.

[@PSA78]

@@sudd3660 I would probably run the woofer in a closed box for a natural roll-off and then take a possible 'hit' with filter in the subwoofer(s) (depending on tuning frequency, as it's pretty much an open baffle bellow tuning frequency in boxes that's vented or use passive radiator). It's not uncommon that they fit a capacitor in smaller speakers (like bookshelf) to protect the woofer, DSP adds the same phase shift as passive with IIR for every order of filter but FIR could be a solution if the whole system is active (I haven't used FIR so it's a theoretical speculation from me, I've heard different opinions of those who have used both for active systems).

[@thinkIndependent2024]

Exception =Acuphase, Maggie's of certain types

[@tubefreeeasy]

I wish more power amps would have subwoofer out jacks. Shouldn’t the sub be set in the center frontal area of a setup? Listener will receive more bass feel and rumble.

[@sudd3660]

stereo subwoofers in each corner behind the speakers or on the sidewalls is a good general rule.

[@grabannon]

Low frequency is omnidirectional. Hard to determine precise location unlike highs..

[@PSA78]

If you can hear where the bass is coming from then it's either crossed over too high or it's playing too loud (both are essentially creating the same problem of high enough dB high enough in frequency so we can locate it). Bass is all about the rooms physical dimensions, your positioning and the subwoofer(s) positioning, so every situation will have it's own ideal placement.

[@Jorge-Fernandez-Lopez]

Center position in any direction is a null (pressure).

[@KevlarCondom]

if room coupling was a true problem, we would only hang our speakers.

[@funny0000000]

FIRST!

[@HansDelbruck53]

Here's a cookie for you 🍪

[@Mark-lq3sb]

@@HansDelbruck53 No thank you. Every website I visit they try to give me cookies. I've been trying to watch my weight...