Sonotube sub bass project

[JBL 4645]

Okay I’m thinking of getting this cheap tubing for those Sonotube sub projects that looks relatively easy and straight forward.

I have those JBL 15” 2226 and was thinking of snapping them tougher with the aid and assistance of friend as he as tools.

I’ve put the question on Home Theatre Shack as they have several DIY sub bass members’ projects happening on the site.

Only think I need to find is the tubing that is used for concrete pillar constriction, basically its cast mould for the concrete to set in.

I have looked though local yellow pages and all I see is (concrete ready mix) I’ll call one company in the morning and find out where I can find a supplier that produces the tubes.

If most Americans have brought these, tubes for around $35.00 dollars then it’s going to be rather cheap project to do.

I plan to place the tubes not vertically but rather horizontally along the each sidewall attached near to the top of the ceiling in the corners (between wall and ceiling).

I was thinking at first 12 feet. The room is only 15 and part of that is taken up from the CRT and JBL sub that stick out the most due to their depth!

So 10 feet sounds like round even number.

What I’d like, is rough idea on the frequency response, that I can stretch out of these JBL a rough wild insane guess.

Also there is an alternative to the tubing and that is the tubes that is used on (road works). I’ve noticed many projects around town and even DIY hardware music live in Bournemouth, on Old Christchurch Road a few years ago.

One was using yellow tubing that is used for gas! It had wicked low beat when banged on that was felt in the chest. Mind you this was outdoors and not indoors where it sound different.

It was basically percussion music with a lot hard beating and rhythm.

Blue tubes is used for water
Black used for fresh water (at least that’s what my dad thinks)

There’s usually off-cuts on sites that end up as scarps so who cares what you want with it. I might look around for some tomorrow while doing the shopping.

[jcrobso]

http://pro.bose.com/pdf/pro/tech_dat...naray_awcs.pdf

I have heard them, about the only BO$E product that I kinda liked the sound.
It is a double tuned bass reflex built as a straight pipe. I think the BO$E used a 12" speaker, it would be interesting with a 15", maybe you could aim it at your neighbors and blow them away!
When you read the PDF they talk about the Panaray digital system controller, I think that this is the real star of the sound of this speaker.
More info of sorts.
http://www.talkbass.com/forum/archiv.../t-105572.html

[Ruediger]

Hi JBL4645,

if I got You right You plan to use a 12 feet long tube with a driver at one end and the other end open.

This thing will resonate when it's length is half a wavelength. At 46 Hz both ends of the tube will radiate with the same phase.

When the length is one or three quarter wavelengths it will not resonate. Then only the driver will radiate sound.

So at 46 Hz You have two sources of sound which radiate with the same phase. This means You will have the same interference patterns as if You had two drivers several meters apart. Along the line perpendicular to the middle of the tube the two sources will add, at either end they will subtract.

Further this thing will trigger room modes. At certain frequencies Your room will vibrate, at others it will not. Your "experience" will be position-dependent.

The problem is that the two sources are 12 feet apart. That leads to the interference patterns. In a large room You might even make some use of that (bass radiator with a non-uniform radiation pattern). I cannot imagine that it's any good in a small room.

You could build a real transmission line by folding the tube in the middle and thus bringing the two ends together. So You would get rid of the interference problem.

Actually that is a very old construction. Search in Google for "Jensen Transflex" and for "JBL Air Coupler". These things were meant to be built into the floor. To protect the driver from people's feet the driver was recessed so that it's at the inside of such a construction and not at the outside.

Looks like a crapped horn Look at page 86 in John Eargle's "Loudspeaker Handbook" if You have that book. There's also a drawing.

Ruediger

[Doc Mark]

Morning, 4645,

I've only heard one system like you describe, back when I lived in Minneapolis. A German fellow, with whom I worked at Schaak Electronics, made such a system using terracotta pipes. It was impressive, but sort of a "one note Johnny", if memory serves. After a bit of listening, I found it rather artificial, at least to my ears. That's all I can add to this, but for what it's worth, I think there are far better systems out there for bass reproduction. Take care, and God Bless!

Every Good Wish,
Doc

[Eaulive]

That'll be my guess as well, it will most likely resonnate at a specific frequency and that's something you don't want for a sound reproduction system.

Of course, if you're looking for efficiency at a specific frequency like the car audio freaks, that'll do

[hjames]

That'll be my guess as well, it will most likely resonnate at a specific frequency and that's something you don't want for a sound reproduction system.

Of course, if you're looking for efficiency at a specific frequency like the car audio freaks, that'll do

Yeah, but any kind of tuned BOOM tube like that should be the LAST THING an apartment dweller ought to get into!

Talk about a guaranteed lease breaker!

That sounds more like something for hip-hop, car-audio gimmick music than for a real audiophile like Ash with his known taste for classic music and film,

[grumpy]

it's still possible to have fun with this:

http://passdiy.com/pdf/el-pipe-o.pdf

[JBL 4645]

Morning, 4645,

I've only heard one system like you describe, back when I lived in Minneapolis. A German fellow, with whom I worked at Schaak Electronics, made such a system using terracotta pipes. It was impressive, but sort of a "one note Johnny", if memory serves. After a bit of listening, I found it rather artificial, at least to my ears. That's all I can add to this, but for what it's worth, I think there are far better systems out there for bass reproduction. Take care, and God Bless!

Every Good Wish,
Doc

Hey there Doc.

Yeah I know what you mean by (one note tone) It needs to address all the tones otherwise like you explained it would be like playing 30Hz to 40Hz no? It needs to do 20Hz up to 100Hz? Or best below 20Hz to capture those rich exclusive pedal organ notes.

I’ve been tired up for the past 24hours and yesterday I had other things on my plate and didn’t make phone call around, to see if I can get an answer on where to get the tubing.

As for the, (yellow gas pipe). I saw works on Commercial road at the centre of Bournemouth, and the piping is far to narrow. I guessed it by eye as (8” to 10”) far too small.

I seen threads on AVS where some have DIY sonotube projects some seem disappointed because they want higher SPL at lower frequency. I guess it’s rather hard to achieve this?

Oh, well at least once I, got some tubing I won’t keep my expectations too high.

[JBL 4645]

That'll be my guess as well, it will most likely resonnate at a specific frequency and that's something you don't want for a sound reproduction system.

Of course, if you're looking for efficiency at a specific frequency like the car audio freaks, that'll do

No way. I don’t want that boomy smearing bass that overwhelms the rest of the frequency spectrum, no way.

I’ve heard a car hi-fi and it sounded dreadful, I mean the owner might as well been playing a sine wave signal note tone, because that what it sounded like.

It was just a load of air turbulence, that’s not music!

[JBL 4645]

http://pro.bose.com/pdf/pro/tech_dat...naray_awcs.pdf

I have heard them, about the only BO$E product that I kinda liked the sound.
It is a double tuned bass reflex built as a straight pipe. I think the BO$E used a 12" speaker, it would be interesting with a 15", maybe you could aim it at your neighbors and blow them away!
When you read the PDF they talk about the Panaray digital system controller, I think that this is the real star of the sound of this speaker.
More info of sorts.
http://www.talkbass.com/forum/archiv.../t-105572.html

Bose, yes, that’s why I’d like to knock it up and place it horizontal in the room. Kinder like the (Bose wave canon), only using a JBL speaker.

Wow 25Hz down that’s not too bad. One would be weight factor issue as the 2226 weighs a bit, at least at one end of the tube it would and it would have to be very strong to withstand the vibrations!

Oh the Bose wave canon 29Kg

A single JBL 2226 8.7Kg Oh, not that bad in weight

[Eaulive]

it's still possible to have fun with this:

http://passdiy.com/pdf/el-pipe-o.pdf

They had fun, they blew two 21" 800W woofers in one party.
I wouldn't like to be at this party...

[JBL 4645]

it's still possible to have fun with this:

http://passdiy.com/pdf/el-pipe-o.pdf

Grumpy Cheers for that link I’ll have read of this.

Yeah I agree its not easy to get 20Hz at high SPL db. I guess the same can be said about 20Khz. Its narrow wavelength will be so small to hear.

I think both requires a lot of power or high efficiency HF to make things easier to produce the 20KHz but if, one has shallow hearing spectrum in the highs then its really not worthy bothering with. Unless your bat?


El Pipe-O consists of very large woofers mated to large cylindrical transmission lines. The goal is to get good powerful response down to 20 Hz at levels where the room starts to rattle before the loudspeaker.

By that does the mean less illumination the barograph display on the amp as I see this often on my amps barograph display.

[JBL 4645]

Yeah, but any kind of tuned BOOM tube like that should be the LAST THING an apartment dweller ought to get into!

Talk about a guaranteed lease breaker!

That sounds more like something for hip-hop, car-audio gimmick music than for a real audiophile like Ash with his known taste for classic music and film,

Yes, but the pipe organ seems good on some classically music and it would serve nice even if this thing me jig only turned out to do below 30Hz or I don’t know I haven’t gotten as far as getting hold or the tubing yet.

But with two side by side of the room it should do something in the room, I’ll have to wait until I get contact number and get a quote on the price.

I like that music that was used in the original Rollerball with James Cann you know the pipe organ music I’m talking about.

[Eaulive]

I like that music that was used in the original Rollerball with James Cann you know the pipe organ music I’m talking about.

Toccata et fugue en ré mineur, Jean Sébastien Bach.
http://www.youtube.com/watch?v=_FXoyr_FyFw

[jcrobso]

Toccata et fugue en ré mineur, Jean Sébastien Bach.
http://www.youtube.com/watch?v=_FXoyr_FyFw

I has been used in many a science fiction movie, the mad scientist play this piece on the organ just before he destroys the world.
I grew up listing to it, my older brother was child prodigy organist he learned to play it when he 10 or so.
On a big organ with a full 32' stop it is an amazing thing to hear!
Organ pipes are just Helmholtz resonators!