Multiple Small Subs - Geddes Approach

That is actually the way to do it. Bias will be dominate in the beginning, but as time goes on it diminishes. But then there is also "acclimation" - where we get used to and come to like whatever we have - sometimes no matter how bad it is.
Agreed. Thing is, I can now almost freely walk around my apartment, even to other rooms... and the base does not change much. It does not become super boomy or thin, like what is very normal with almost any standard set of stereo speakers with no subwoofers.

It is very interesting to listen to music, watch anything on YouTube, watch a movie or simply play a game, because now everything sound deep, high, low and all those bla bla hifi-terms in all occasions, according to the actual source of the sound. So if a recording is crappy on YouTube - you'll hear it slightly crappy. But the thing is, suddenly the sound is less annoying, because the sound is simply what it is. So it is kinda like real crap - not glossed over crap - which actually sound way more natural and pleasant :D

We all know that they fiddle a ton with the music in the studio anyway... and that most movies and games are excessively mixed up with whatever they wanted, to create a given result... so nothing natural about this. All we can do is try and represent the source material as neutral as possible... with a little extra "oompf" in the bottom end... because that sound much more fun when you first got the subwoofer/midwoofer integration very smooth and even - also with respect to our lower sensitivity in the lower frequencies.

Another thing. I must say, that a lot of people seem to forget that you have to interpolate for yourself. Certain things in hifi can be made into general rules or guidelines. But as soon as you start to put all sorts of combinations of subwoofers, rooms, placement, EQ, amplifiers and so on into the mix. You simply have to put in the effort yourself to find what is compatible with your choice of gear, when you try to pull out the essence of someone else's work or success in reaching for example a good neutral sound with a given set of speakers/subwoofers.

I myself, included, sometimes fall in love with some tweeter or woofer, and then try to hammer all other theories in place with that one or few choices, to see if I can still reach audio nirvana - without changing that original choice, because that is my "precious" first idea or focus. Silly but true :ROFLMAO:

It's like baking a cake, where you have to grasp that each ingredient is more or less significant, and maybe more or less so, when combined with anything else. And that the final taste - is the combination of it all, no longer a single ingredient all by itself.

Seems like so many are complaining about bad advice or that it won't fit their specific case. When in reality, they should learn better to understand the compromise that they already put on themselves to begin with, before they ask for the magic cure to fix what they kinda chose to be stuck with.

Earl, I applaud your work - but at the same time I must admit that creating my own version of what you have done - is not a mere copy and paste, but a learning curve, which is actually some of what this hobby is all about :)
 
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Juicy, strong, extremely muscular. Controlled. 4,2 liter Closed box per woofer. Extremely top notch small subwoofers.

https://www.jlaudio.com/collections...ducts/6w3v3-4-car-audio-w3v3-subwoofers-92145

I have never ever heard anything more musical in a car. I run two as front subwoofers in my car. DSP all channels.

The rear subwoofer in closed box is the really really good s**t:
https://www.jlaudio.com/collections...ducts/8w7ae-3-car-audio-w7ae-subwoofers-92117


But in pure ”musicality” the twin small front subwoofers wins the gigantic smile. Any day of the year.🙂

But thats just my taste and take on it🙂
 
Agreed. Thing is, I can now almost freely walk around my apartment, even to other rooms... and the base does not change much. It does not become super boomy or thin, like what is very normal with almost any standard set of stereo speakers with no subwoofers.
Agreed. Thing is, I can now almost freely walk around my apartment, even to other rooms... and the base does not change much. It does not become super boomy or thin, like what is very normal with almost any standard set of stereo speakers with no subwoofers.
We need to keep these various perceptual issues separate. What you are talking about is also known as the "Toole critique". It implies there's no sense in tuning a room since your hearing adjusts for the room and Uncle Harry sounds the same everywhere you might be talking with him.

My own take is that you need to get the sound delivery right, not the room. That would mean the speakers, directionality, and maybe some disruptive features of the acoustics that interact in ways with the speakers.

I don't know as this has a name within psychology or just how you'd study it.

B.
 
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We need to keep these various perceptual issues separate. What you are talking about is also known as the "Toole critique". It implies there's no sense in tuning a room since your hearing adjusts for the room and Uncle Harry sounds the same everywhere you might be talking with him.

My own take is that you need to get the sound delivery right, not the room. That would mean the speakers, directionality, and maybe some disruptive features of the acoustics that interact in ways with the speakers.

I don't know as this has a name within psychology or just how you'd study it.

B.
I try my best to measure my speakers gated in the middle of the room, with minimum reflections, so to get the sound from the speakers as correct as possible - per Toole's theories. In the woofer range, I believe we can fiddle a bit, since we are now going into Schroders "domain". As we move into 100Hz and below, we are almost purely talking level as a total goal - whereas the level of each sound-source, no longer matters as an individual - only the sum.

I remember the quote - Floyd in this room and Floyd in that room. I kinda agree... but I think that a room which is comfortable for talking and normal daily activities - usually also is an ok start for hifi listening.

Trying to dampen the room, as we go down in frequency, is hard - big. I try to keep the room nice to be in, both for speech and practical living conditions. Then I focus on the speakers and mostly go for avoiding the worst first reflections. I could do better, but I need to start somewhere, and where I feel that I get the most output/quality first - then the icing on the cake can follow as I move down the hifi-road.

I never said that I knew how to reach super sound and my advice or way to do things was the best. I'm simply trying here.... trying to have a blast, live a life and enjoy my hobby. As I already wrote... some things rarely change, but the rest we have to adjust to all the compromises that we already chose.

I do not feel like I studied it... maybe I did... cause damn... I read and tried a lot :ROFLMAO: :geek: I also make many experiments and try if I can replicate the phenomena and or theory, at friends places. Mostly, the distributed bass seems to be a rather sturdy theory, which also seem to work out pretty well in praxis - everywhere. It's one of those things that just work - if done right... even half right, and you still get some kind of improvement.

And just because... I can... I'm now trying out new waveguides and cabinets for my midrange and tweeter. Then measure and listen to music.... we cant forget to actually listen to music... and forget a bit of all these theories... so it won't feel too much like work :giggle: :D
 
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Earl, I applaud your work - but at the same time I must admit that creating my own version of what you have done - is not a mere copy and paste, but a learning curve, which is actually some of what this hobby is all about :)
Thanks.

I have always said that LFs in small rooms needs to be done with a very wide brush. There are few things in this regime that are set-in-stone.

One woofer is better than no woofers and surely two are better than one, and three will almost always be an improvement. Four gets to the 50/50 point where it may or may not be an improvement. But beyond that almost everything is open to interpretation and experimentation as there is no one-way to do things.
 
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Earl, do you know if Toole makes speakers? Good commercial offerings can be hard to find and I notice Toole making some choices that I probably wouldn't make myself. I wonder if things would relate differently if he was engineering both sides of the coin.
 
Floyd just got remarried (his wife passed away). Last I talked to him (not long ago) he was happy and content to be retired. But I don't think that he ever made any speakers himself. Even now he says his system is Sonos.

My son tried and tried to get a job at several audio companies (Harmon, Sonos, etc.,) but nobody bit, even after several nibbles. But he just landed a job at Morgan Stanley on Wall Street in cyber security for more money that I could ever have imagined - right out of college. Audio - as we knew and loved - is a thing of the past.
 
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My son tried and tried to get a job at several audio companies (Harmon, Sonos, etc.,) but nobody bit, even after several nibbles. But he just landed a job at Morgan Stanley on Wall Street in cyber security for more money that I could ever have imagined - right out of college. Audio - as we knew and loved - is a thing of the past.
It seems, that many people now just buy something almost good enough... which in return simply is easier, smaller and uses less power. Convenience over quality, I guess. Could also just be a priority - a choice.

It's also business... When you can reach millions of people with small, cheaper and ok devices - and music anyway is going in the wrong way when it comes to audio quality (loudness wars ) - then it's a big ship to turn.

I have been thinking for some time, that maybe in the future, we could make like an event HIFI room, where people can come to try how music used to sound. No clipping, loudness wars, full frequency spectrum anomalies, no compression, phantom center all that fun stuff that makes these Bluetooth products sound like a weird little annoying dog that tries too hard to be big and scary - like going to the cinema should be like - a wow experience.

Dynamics too.... small speakers, no subwoofers + overly compressed music, equals very little dynamics and sense of greatness when the drums or beat kicks in. It is just like one big wall of distortion and sound.... not the fine nuance of going from a small whisper to a large smack on the kick drum, while keeping everything in balance and not losing power/breath during the transition from low to high.

I sat yesterday, after mounting an SB 26ADC in a 5" Augerpro waveguide, to mate with my SB MW13TX in some new cabinets(still with 2 woofers and four subs - of course). Listening to Michael Jackson, Phil Collins, George Michael and a few of the older ones. All new music is definitely not bad, but maybe it was the gear they used back then, which forced them a little bit to do a better job - or maybe I'm just nostalgic :ROFLMAO: Thing is, even at low volume, you still have a sense of beat, while maintaining the distinct sound of the artist voice.

I enjoyed it, which is an awesome thing to experience, when constantly being in the middle of building or tweaking something :D

Happy for you and your son. I know how it feels to search for a job high and low - working with anything from construction to research and development - now a multi facetted technician at a small factory - using a good mix of my hands and brains every day - 4 days work week and a 4 min. bike trip.

Sorry if it went OT. I think I just tried to point at the possible good things that can be had, even though times change a lot of things around us :giggle:
 
digitalthor, this sounds encouraging. Glad to hear it's going so well.
Thank you :) I think I turned a corner, where I have started to look at things upside down sometimes - brainstorming, in the sense that building HIFI, should be going backwards from what you like in music. If simply hearing the voices and a noticing a simple beat - then you can get away with rather simplistic HIFI systems - even a small radio.
But if you want all the typical HIFI stuff... then it's back to the drawing board and figuring out what it actually requires reaching that goal. My happiness now - and maybe the encouraging tone you noticed. Might be hidden in that fact that I increasingly aim a bit firmer for what I believe is right and worry a bit less too - even though someone feels or tells different.
 
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Yes, I think I'm at my best once I understand a concept and begin pursuing it on my own. Then I use the forum to connect with people who have done it and who understand it. If you're not sure who that is then you can try taking smaller steps in learning. This internet has a signal to noise ratio you wouldn't expect from a textbook :)
 
Yes, I think I'm at my best once I understand a concept and begin pursuing it on my own. Then I use the forum to connect with people who have done it and who understand it. If you're not sure who that is then you can try taking smaller steps in learning. This internet has a signal to noise ratio you wouldn't expect from a textbook :)
Haha... so true ;) I mostly try to do what makes me happy. And sometimes hard work, dedication, pursuing knowledge, and scratching my head to figure things out - is what makes me happy in the end.
It's a good mix of theory and actually getting your hands a bit dirty. One can't exist without the other.

Is there a thread somewhere, where the discussion is about where we come from and why we build like we do? I mean HIFI - not necessarily existence as a whole ;)
 
I don't know as this has a name within psychology or just how you'd study it.

B.
It has a numerical reference which is universal law matter where you’re using it unfortunately making a connection to what you’re comparing to specifically is the hard part.

360 into 12 parts is 30.

and then 1÷12 and 11÷12 and 10÷12 along with five and six /12 are very important.

as Soon as you put it into the making of sound , or better, in a speaker ducting, it starts to show why.

Connection between reciprocal , or in numbers opposing in degrees on a wheel. Imediate phase or unwrapped phase).

.833333333/1.2

Same as 360/432 as 0.83333

seconds in a day vs per hour

432/360 as 1.2

adding them up you get 2.033333

0.08333 -.12222 is Part of the optic nerve function flipping bewtween unconscious processing information all day every day.
You see, you go blind- your brain thinks, processes- your brain spit back out info- your regain concousness, you see you , repeat Anniversary throughout the day or night whenever. The same pattern is in the yeaThe same pattern is in the ear/hearing.

and that wheel around around the whole time and see how they all relate.

OK but the bigger pictures or bigger or the same thing to see how the numbers are interwoven in other ways

exact thing put it out for everyone to see so no one even think to look at Leap year. 360 vs 365.2xxxxxx 360 x 4 is 1440 vs 1461.

Yes 1440 minutes are still in 24 hours and 720 in 12….

what’s the big deal?


well it’s exactly the opposite of Saturns location on top of earth location verbatim.

96:1(9.58AU to 1AU).
And you can draw same shape that is gathered on the pools of Saturn in the storms and the magnetism of the ionized gases causing it at the poles.


1728/1728/1728 (sqr root of 3) making isosceles triangles that form a hexagon on top of earths orbit the mathematical reference to the circle using Kepler Laws (mean average not eliplse)

Four days worth of seconds 172820 is really directly to voicemail to the reason why Saturday we order the race is 1433.5 and earth is 149.6 Same reason Mars is opening at approximately the exact location of uranium 235,236,238 In milion kilometers away from the sun. It’s there after that everything falls apart as well until you arrive at Jupiter work we have a repeat all the way out to the kyber belt And then the Oort cloud and the same sequence that you get overlaid on top of that. Nobody understands this building speakers? yet building speakers to certain wavelengths or (1/4wave plus an offset chaner) that cures this more than anything else.

if it fixes the sound in that area what else does it do, With the same numbers?

Go to 300 cm x 0349206. That’s 104.76 cm times three equals pi. What is soon as you put that into a compound pipe number change it to 05238095 6.2857142 instead .

1/12 and 11/12 from the ends. Look what happens when you build that into horn response at 860 Hz and 1720 and 2580, 3440… and so on(14620) …

And then to see how everything is connected and how this timing thing or sealed boxes( if you wanna give in to nothing to learn as a human or a curious person is interested in any of this case something got missed along the way overtime? ) it certainly seems like multiples of that has occurred and always will. There’s nothing to do with sound or anything in particular it’s how everything works amongst humans it’s what will eventually kill us all. I will never pay attention to the real mechanism lol standby 18 million wrong answers that smeared it. Government and religion including obviously in the grand scheme of things.
Is your reality or your perception of it actually in phase? Starts with a hearing and in our vision but you can go all the way into anything, is schizophrenia condition where people are not in tune to reality? Or are those individuals technically more in tune with reality than we are and we don’t even consider that for a moment…
Floyd just got remarried (his wife passed away). Last I talked to him (not long ago) he was happy and content to be retired. But I don't think that he ever made any speakers himself. Even now he says his system is Sonos.

My son tried and tried to get a job at several audio companies (Harmon, Sonos, etc.,) but nobody bit, even after several nibbles. But he just landed a job at Morgan Stanley on Wall Street in cyber security for more money that I could ever have imagined - right out of college. Audio - as we knew and loved - is a thing of the past.
cyber security.., if his acoustical science and math background is anything like yours he’s gonna do good!
That’s all this book is about endlessly… references to everything we find in building a subwoofer as in the acoustical shapes (rectangles ) and lengths / quarter wave parts and also the frequencies and out of band equivalent freqs …

this stuff is weird, but for some reason I can’t find any of it that doesn’t actually work already? In fact it’s kind of like reading a book about how to do we’re all already doing(Minus the sawdust and the reference to speakers.
 

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Hi all :)

I just finished reading my way through this 128 pages thread.

I am very happy that I did find it, as the Geddes approach solves a major concern for me! Thanks 😊.

I am planing to build some very big synergy horns / MEH's, that I had planed to cross over to some big corner subs at around 80 Hz, thinking in 1/4 wavelength-summation-terms as in the whole synergy approach. I have spend much time speculating, how to blend/crossover the MEH and the Sub phase-coherently! How to measure and set up the crossover IN my living-room? Bla bla bla:eek:. My room is roughly LxWxH 8x4x2,45 meters or 26x13x8 feet.

And now this thread basically tells me: Don't worry mate, it's not even possible, the room will mess it up anyway! Let the MEH's go full range down and support with multisubs to get good bass in a much broader space. Tadaaa, problem solved (I hope ;))

I just need to build more subs to spread around in the room.

Thank you Dr. Earl Geddes for sharing your knowledge and keeping on explaining things.

Well, and now I will go out to finish one of those endless projects that keep on preventing me from building speakers!

Have a nice day

Steffen
 
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