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Vasubandu's Tower of Subwoofer Build

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3 minutes ago, MetropolisLakeOutfitters said:

That's why I keep telling you to make big giant ports.  

 

There's two things that kill a sub's sound the fastest, one is port noise, second is box coloration / ringing, both of which are due to undersizing.  Most people's complaints revolve around port issues though.  

 

Thanks again.  I assume that when I actually have the actual measurements to work with, some software will indicate optimal port size, or is it more subjective than that? I also have been looking for anything about port location but have not come up with anything useful. Logic suggests that it would matter.

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1 hour ago, CECAA850 said:

I think that at this point, anyone who wishes to answer the OP's questions on subwoofers is welcome to do so.  All other posts aren't really necessary.

 

I kind of have to agree with this.  I am not trying to offend or annoy anyone. If no one here is interested or wants to help me, I can just take this elsewhere. Was never my intention to create a commotion.

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21 minutes ago, MetropolisLakeOutfitters said:

That's why I keep telling you to make big giant ports.  

He'll probably only need one 6" hole in the side of the tube.  Depending on tune, maybe 2 inches long max.

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Thanks @CECAA850  I have the HS-24 set up in WinISD, but it says something is wrong - missing information I think. Using what I have  witih a 1200 liter volume, which I will have,  wit one 5 inch port, the rear port air velocity is off the charts below 42.  A 10" is not much better, 2 10" has me over 14 from 25 down, 3 10" limits the over 14 to 15-20, and 4 10" peaks at 12.25 around 18.  I am still figuring WinISD out.  The rest of the criteria that I understand still look good with 4 10 inch ports.  

 

I am not sure why I would want to limit the ports and am still learning that.  

 

I appreciate your taking the time to comment.  If you want to check in from time to time and offer an occasional comment, that would be appreciated, but I won't expect you to help me.  Whatever works for you will work just fine for me.  

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There has been more research and sub designs over the decades than likely everyone on this site can even imagine.  I think its cool you're trying something different, but I would look at SVS's cylinder design and why all the different cylinder models were phased out except one.   Just on what you're going to invest in hardware, have you considered a horn loaded sub?  Jason can hook you up with some plans for some of the best horn loaded sub models known to man right now.  I respect the fact that you want to build something different, but when you have some stellar Sub companies out there pushing the envelope everyday and trying new ideas, you either need to clone one or buy one.   Personally, I would build something that I could market or re-coup some money once I lost interest which would lean better with a proven design.

 

Having said that, have you considered dividing the cylinder and separating the two drivers and porting each end? This might make tuning a little easier and offer offsetting port sizes and lengths for each end giving you something tuned lets say @ 30hz to 40hz and the other end tuned at 20-25hz.  That may be a Kamikaze mission, but it would offer experimentation and something to mess around with. 

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29 minutes ago, Max2 said:

Personally, I would build something that I could market or re-coup some money once I lost interest which would lean better with a proven design.

 

Having said that, have you considered...Snip!

You should have stopped with "lean(ing) towards a proven design!"  :P

+++

 

Hey @vasubandu I have an interesting proposal for you that may help you to fulfill your desire to build a sub, without investing $5000.  Shoot me a PM if you are interested. 

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11 minutes ago, Max2 said:

There has been more research and sub designs over the decades than likely everyone on this site can even imagine.  I think its cool you're trying something different, but I would look at SVS's cylinder design and why all the different cylinder models were phased out except one.   Just on what you're going to invest in hardware, have you considered a horn loaded sub?  Jason can hook you up with some plans for some of the best horn loaded sub models known to man right now.  I respect the fact that you want to build something different, but when you have some stellar Sub companies out there pushing the envelope everyday and trying new ideas, you either need to clone one or buy one.   Personally, I would build something that I could market or re-coup some money once I lost interest which would lean better with a proven design.

 

Having said that, have you considered dividing the cylinder and separating the two drivers and porting each end? This might make tuning a little easier and offer offsetting port sizes and lengths for each end giving you something tuned lets say @ 30hz to 40hz and the other end tuned at 20-25hz.  That may be a Kamikaze mission, but it would offer experimentation and something to mess around with. 

 

Thanks @Max2.  I have been more careful than it may appear about costs.  Most of it cane be easily recovered or reused.  I could just make one or two new subs with the drivers, and the amp will power both  however it is done. The wooden tube will run me $500, and if it does not work out, I will have to find some other purpose for it or burn it.  Maybe I will keep the door on it and sell it to Seattle as a prototype for a green public restroom.  I am guessing that I will have about $1,000 of nonrecoverable costs into it.  That is not insignificant, but considering how many hours of fun I will have with it, not bad entertainment value.  

 

If I know nothing about subwoofers, my knowledge of horn loaded subwoofers goes into the negative.  It is a very intriguing thought, and I need to check it out;  Do they have similar sealed/vented and space issues, or are they just totally different?

 

I have indeed thought about separating the spaces as you suggest. It will be designed with that in mind so that I can easily create the separation without removing a driver.  With the door, I should be able to try all kinds of things with it, and my notion was to develop the ability to measure the effects and keep good records.  Sort of more laboratory than subwoofer.  That is what I have not explained very well to everyone. "Experimentation and something to mess around with" as you put it is about as good as it gets for me.

 

And by the way you are dead right about the R&D.  There are a lot of subwoofer patents in the works, and some of them have radically different ways of producing sound.  I don't even understand a lot of them.  The same it true of speakers. I am still stuck on the one that uses air to make sound.  No kidding.  This is their speaker.

 

wave-1024x994.png

http://www.waveion.net/

 

I sent an email to the guy behind it, and he actually responded.  Sometimes people will.  This is what he said.

 

Ionic loudspeaker, located in the upper part of the acoustic system provides the pulsation of the air column, thus generating axially symmetric sound waves propagating with one phase at 360 degrees. It also has a pronounced vertical orientation. The higher the emitter height, and the higher the signal frequency = the higher directivity. 

 

The sound pressure level of one loudspeaker is 40cm in height and at a distance of 1m at a frequency of 1kHz - 93dB. 

 

In some laboratory prototypes, we managed to develop the volume in 110 dB.

 

The non-scalable parameter is the interelectrode distance in a few centimeters. A loudspeaker formed by a system of electrodes, can have any shape and accordingly radiation direction.

 

Let me ask you, what is the reason for your interest, because our team does not have enough time to personal answers.

With the information you are interested you can read on our website.

 

Sincerely,  Chief Engineer Maksym Chyzhov.

 

And then there is the speaker with no moving parts.  

web_Good_Vibrations__main.jpg

Researchers have combined speaker,

amplifier and graphic equaliser into a

chip the size of a thumbnail.

 

http://www.exeter.ac.uk/news/featurednews/title_581068_en.html

 

For that  matter Apple's new speaker is behing hailed as audiophile quality.

 

Reddit audiophiles test HomePod, say it sounds better than $1,000 speaker

https://arstechnica.com/gadgets/2018/02/reddit-audiophiles-test-homepod-say-it-sounds-better-than-1000-speaker/

 

 

Of course, anyone who knows anything will tell you that the tried and true methods are best, and that anyone who thinks outside the speakerbox is a fool and wasting their time.

 

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10 minutes ago, CECAA850 said:

Don't get caught up in hyperbole and marketing.

 

Good point.  I am going to cancel that air speaker order.  Or maybe I will just send them back if they don't sound great.  

 

And actually, when something interests me, I try very hard to drill down to the original source. I read an article on the air speaker, but it did not give the company name,. Took me a while to find them, and then I wrote to the company for information.  I am always surprised at how willing people are to share information if you ask them for it. But the air speaker is pretty much all smoke and mirrors.  Its domain name was purchased from Godaddy.com in 2016, and its domain is held by domainsbyproxy.com.  Not the sign of a substantial enterprise.  

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There's not much new under the sun as far as subs go.  There's only so many ways you can combine a box and a driver and they've all been pretty much tried.  There were a few innovations that really peaked my interest.  One that Klipsch came out recently was very innovative.  They horn loaded the driver which in itself is nothing new BUT they then horn loaded the port as well.  That's the 1802 that Roy came up with.  Another one that I liked was the fan sub that used the pitch and speed of the fan blades to vary the frequency.  They were outstanding from 2 to 20 Hz and then a normal sub was needed to take over.  They also had to be built into your house ala IB sub like I have.   Tapped horn subs are nothing new but they have really been refined as of late.   Push pull slot loaded are neat to look at and play very cleanly but a box/tube and a couple of drivers has been done many many times.

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Some of the stuff I cam across invovled thing like vibrating thicker material - like half an inch thick, some stuff with various carbon substances, so nano particle stuff which made no sense to me, and something that generated a controlled shock wave.  Some of this was in patent applications, which is supposed to mean that it can be shown to work.  Our bidies make sound with vocal cords.  why not something based on that?

 

My impression so far is that sound generation has pretty much escaped the advance of technology.  I don't count doing the same thing the same way better to be the advance of technology.  We can digitize sound, but the end point is still analog.  Sound waves are just inherently different from electricity and light. The only word I can come up with for sound is primitive.

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18 hours ago, wvu80 said:

You should have stopped with "lean(ing) towards a proven design!"  :P

+++

 

Hey @vasubandu I have an interesting proposal for you that may help you to fulfill your desire to build a sub, without investing $5000.  Shoot me a PM if you are interested. 

Sometimes you have to throw in the towel and just embrace what is in front of you :D     A lot of smarter guys than me already trying to steer Vasubandu in a different direction.  Lots of guys here have some insane Sub setups with multi 18" in wall and what not, but I cant stand having my sub turned on unless its a movie.  Its a damned insult to my K-horns running @ 2.1 :)

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20 minutes ago, Max2 said:

Its a damned insult to my K-horns running @ 2.1 :)

I'll bet @Mallette would beg to differ especially if you're listening to musical content with deep bass.  Sometimes it's nice to have that extra octave.  I made a believer out of him.

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18 hours ago, vasubandu said:

I don't count doing the same thing the same way better to be the advance of technology. 

  Subwoofers have embraced and benefited from new technology.  They're light years ahead of where they were 10 to 15 years ago.  Advances in dsp and surround material are 2 things that come to mind.  Magnet materials are different.  Cone materials are different.  Drivers have amazing x-max numbers now.  Reproducing bass waves is all about moving air and subs today are better now than they ever have been at doing just that thanks to technological advances.

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1 hour ago, CECAA850 said:

I'll bet @Mallette would beg to differ especially if you're listening to musical content with deep bass.  Sometimes it's nice to have that extra octave.  I made a believer out of him.

Indeed.  And PWK helped.  PWK was an organ lover, and that was part of his reasoning for the K'horn to extend flat only to 32hz, or C1 which is the first pedal of an organ with 16' pipes.  The vast majority of organs at the time he designed the K'horn had no pipes larger than that.  As to records, the medium of choice of 99 percent of people, E. Power Biggs "French Organ Music" is generally credited as being the first public release of an LP good to 32hz and that was long after the K'horn was designed.  PWK told me that due to the design goal of building the highest fidelity, most efficient loudspeaker physics would allow had corollaries.  These were an acceptable footprint, and a reasonable cost.  He said on numerous occasions that the K'horn could reproduce 98% of recorded music.  

The only instruments that extend significantly lower than C1 are the pipe organ and the grand piano.  Grand piano gets to about 21.7.  This explains to me that, while I always preferred the K'horn on the majority of music, the Frazier Eleven was my speaker of choice for piano.  It had quite a bit more at 21.7 than the K'horn.  

Point is, for those who love pipe organ they have no need of C0.  But for those of use who listen to large pipe organs the K'horn is not "high fidelity" for these recordings.  So we need a great, preferably, horn loaded sub to handle them.  And, set to roll off at 32hz, you only need one as sound between C0 and C1 is not directional to the ear.  

 

Dave

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4 hours ago, Max2 said:

Sometimes you have to throw in the towel and just embrace what is in front of you :D     A lot of smarter guys than me already trying to steer Vasubandu in a different direction.  Lots of guys here have some insane Sub setups with multi 18" in wall and what not, but I cant stand having my sub turned on unless its a movie.  Its a damned insult to my K-horns running @ 2.1 :)

 

I would never throw in the towel until it was the last thing I had.  And I have taken @wvu80 up on his offer, which present more an additional rather than different direction. I still do not see what is so deviant about my project.  It is dual opposed HS-24 drivers in an enclosure with amount of space recommended by the designer.  The space is all entirely open.  It will have the appropriate number and type of ports as determined by calculations.  It is true that I am starting with the enclosure and working backwards, but just about any series of calculations can be done starting with the variables or the result to reach the same answer.  

 

Your comment about the K-horns makes complete sense.  In a perfect world, our speakers would cover the entire range adequately, and we would not need a secondary source.  Like you, I really could not imagine listening to music with a subwoofer.

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4 hours ago, CECAA850 said:

Subwoofers have embraced and benefited from new technology.  They're light years ahead of where they were 10 to 15 years ago.  Advances in dsp and surround material are 2 things that come to mind.  Magnet materials are different.  Cone materials are different.  Drivers have amazing x-max numbers now.  Reproducing bass waves is all about moving air and subs today are better now than they ever have been at doing just that thanks to technological advances.

 

When I started this, I really thought that my 2004 PB2 Plus was as good as current subs, just older. I thought that there were come improvements along the way, but the basic design was the same, and I expected that performance would be within fairly narrow parameters.  Comments by @CECAA850 made me go do some serious research, and it showed that he is absolutely correct.  Far more correct than I thought possible, and really more correct than he says.  If I think back to a 2004 model car and compare it to one made today, the difference is night and day.  Not just in terms of style, but performance, efficiency and quality.  The difference in subwoofers over the same time seems to be vastly greater than the difference in cars.

 

It was when I finally got what @CECAA850 was saying that I realized the stupidity of pursuing that 2000 B4 Plus.  No matter how good it was at the time, a pair of good current 12-inch subs would run circles around it. I really don't see the same advances in other speakers.  I guess subs just had more room for improvement.  Anyway, I was dead wrong in going for 15-year old sub designs, and it really colored my perspective about what is possible with subwoofers today.

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On 2/13/2018 at 4:34 PM, vasubandu said:

 

 

wave-1024x994.png

 

 

I’m certain I saw this in the original Hustler store here in Cincinnati sometime in the mid 1980's...

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