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Ralf
11-10-2003, 04:12 PM
In the threat "I would like to introduce myself." you can see my system.

Everything sounds very fine, but naturally the rear loaded horns like 4530 have a delimitation in the range starting with 50 Hz.

So my idea is to create a subbase (vented box) which goes down to 20Hz (16Hz/-3dB).

This stage should insert itself harmoniously into the existing sound.
That`s not so easy, because the 4530 have an enourmous sound pressure.

The best way should be 4 18" Shearer Horns, but this dimension are too large for my small home (and it`s also not possible to go down to earthquake-frequenzies)....

The highpass cutoff should be 50Hz, aktive separated.

Has anybody build a system, which goes down to these deep frequenzies?

Is it possible with 4 2245H?
(my software said no....)

TimG
11-10-2003, 04:45 PM
You probably won't be interested since this design doesn't use JBL drivers. This is a free horn design from Tom Danley, the product engineer for Servodrive/Sound Physics Labs.
This horn design can reach 16Hz, in a home setting, with proper equilization. It was designed to be used 4 per side if used for live sound reinforcement. Here are some links
LABsub design
http://www.prosoundweb.com/lsp/
LABsub discussion forum
http://www.prosoundweb.com/community/forum.php?board=3

Alex Lancaster
11-10-2003, 04:54 PM
Tim:

I cant download the links.

Alex.

Ralf
11-10-2003, 05:07 PM
look at your own:

output (http://www.prosoundweb.com/lsp/response1.gif)

Ralf
11-10-2003, 05:45 PM
the 4645C could be a beginning for my consideration.

I have not found anything about the 121H. Do you have a link to a spec file?

Ralf
11-10-2003, 06:05 PM
Hi Giskard,

I believe, that the JBL/Urei 5234A Network has a jumber inside to cut such subsonic frequencies. But I can`t find the users manual at the moment.

if you have 4 18" cabinets, it should be possible to get a win of 12dB. Is it right?

With a little bit equalizing it could be reached the magic border line down to 20 Hz...

TimG
11-10-2003, 06:50 PM
Using Unibox, with a pair of 2245H in sealed boxes with at least 4.8 cu ft per driver, I get 104.5 dB at 16Hz at 1M, before room gain, at xmax. If you your room has rigid walls and you place the drivers together in a corner I would expect at least 112dB at 16Hz.

With 4 drivers you are looking at 110.6dB anechoic at 16Hz. THis would give you close to 120dB with room gain. You would be hitting 120dB anechoic at 27.8Hz.

These models do not account for driver compression and it does not tell me how much power it takes to hit xmax.

gyusher
11-10-2003, 08:27 PM
Better watch out for the "Brown Note". . . .LOL. . .

GordonW
11-10-2003, 09:43 PM
Speaking, as TimG was, of Tom Danley...

If the LABHorn sub isn't enough, then you could always hunt up the parts to put together one of Danley's "Contrabass" servo-motor subs. ONE of those, will put out 120dB @ 20 Hz, in free space!!

There's a fellow around here, that used to have TWO of these in a home living room. He claims that this sub setup managed to crack EVERY LAST drywall joint in his house, and stated that the drywall ceiling fell in on him once, due to the bass. :eek:

THAT is "enough output", I'd think...

:rockon1: :band: :rockon2: :dancin: :nutz: :jawdrop:

Alex Lancaster
11-11-2003, 07:22 AM
Gordon:

Where do We get more info on the Servo motor bass?.

Alex.

TimG
11-11-2003, 08:43 AM
The website is www.servodrive.com
Here is the link to the contrabass http://www.servodrive.com/contrabass.html
About 9 years ago Tom convinced his boss to let him offer the parts to build your own, but that offer didn't last very long. Tom Danley suggested that you could build something similar using a pair of 12" Labsub drivers and 2 15" PRs per box, here is the link

http://db.audioasylum.com/cgi/m.pl?forum=hug&n=51377&highlight=lab12+tomservo&r=&session=

PM me if you want more info, since this topic is not about JBL drivers.

4313B
11-11-2003, 09:52 AM
"I believe, that the JBL/Urei 5234A Network has a jumber inside to cut such subsonic frequencies. But I can`t find the users manual at the moment."

5234A Manual (http://www.jblproservice.com/pdf/Vintage%20JBL-UREI%20Electronics/JBL-5234A%20manual.pdf)

5235 Manual (http://www.jblproservice.com/pdf/Vintage%20JBL-UREI%20Electronics/JBL-5235%20manual.pdf)

4313B
11-11-2003, 09:54 AM
Forget I mentioned the 121H. It's too difficult to explain how to employ it. Besides, it simply isn't efficient enough, even in quantity, for your particular application. Forget I mentioned the 2245H as well. It's also too difficult to explain how to use it.

You can buy or build a few 4645C's, and EQ them if desired, or you can go out and buy any of the other fartknockers currently on the market for significantly more money.

Niklas Nord
11-11-2003, 10:28 AM
What would be possible with a TacT RCS 2.2x and two or
four JBL 2245H ?

It would be possible to put the 2245s in sealed enclousures
and EQ it down to 20hz.. And put them in corners..

Or would it not?

If we then hook this up to an ampfilter capable to deliver
1200watts into the 2245s...

THAT would be something

4313B
11-11-2003, 10:47 AM
It has been my experience that the 2245H in a sealed enclosure doesn't necessarily need electrical EQ nor does it need to be specifically placed in a corner. In general, the 2242 is easier to boundary load than the 2245. I almost always employ a minimum of two subs regardless of diaphragm size.

A 2245 in a sealed enclosure gains some protection from the restoring force of the trapped air and won't unload below resonance. It has significantly less group delay. It ultimately extends much deeper than it's ported counterpart. It EQ's (EQ here refers to natural room rise) naturally with a typical room more successfully. It's transient response improves significantly. It's intermodulation distortion is greater at the same frequencies that it's ported counterpart is tuned to. It's efficiency is significantly lower as well. In short, it is my personal opinion that it is excellent for a typical home listening environment and less than ideal for situations demanding maximum SPL in the VLF.

*****

For clarity

Niklas Nord
11-11-2003, 10:49 AM
Aha
what volume are we talking about for the 2245 and 2235 here?

4313B
11-11-2003, 11:08 AM
It depends. Set the system Qtc for 0.5 to 0.7 and figure the required volume accordingly. A Qtc lower than 0.5 begins to enter the realm of infinte baffle as opposed to acoustic suspension. That is where the trapped air volume begins to no longer be able to add any restoring force to the moving assembly. I personally like Bessel responses (Qtc = 1/sqrt(3)) but Butterworths are maximally flat and can be quite nice (Qtc = 1/sqrt(2)). In reality it usually takes a pretty trained ear to be able to tell the difference between a sealed Bessel and a sealed Butterworth.

Niklas Nord
11-11-2003, 01:59 PM
Aha okej!
Then a simple testbox will be the thing to try

4313B
11-11-2003, 02:08 PM
You got it ;)
Test boxes are fun :)
I can sit here and tell you all kinds of stuff until the cows come home but until you try it yourself and see what's going on you'll never get the experience first hand.

Niklas Nord
11-11-2003, 03:02 PM
What do you talk about?
I dont own a cow ??????


:D

4313B
11-11-2003, 03:56 PM
Well, I guess we'll have to wait until mine come home then :D

Paul D
11-12-2003, 02:19 PM
I have 4 X 2245's in homebuilt cabs similar to the B460. I would like to know how your project turns out! My cabs are ported but
I always thought about using sealed cabs. I have heard the Infinities with 4 X 12" woofers per side in sealed cabs and they
were quite impressive.

Do you think a sealed design would eliminate the boominess that ported enclosures can have?

Ralf
11-12-2003, 05:21 PM
What you think about?

with 4 of these, I should get a maximum sound pressure of 133dB@50Hz (129dB@20Hz)...

boputnam
11-13-2003, 11:11 AM
Originally posted by Ralf
with 4 of these, I should get a maximum sound pressure of 133dB@50Hz (129dB@20Hz)... Yikes!

Can you hear me now...? :duck:
Can you hear me now...? :duck:
Can you hear me now...? :duck:

delahais
11-13-2003, 11:18 AM
Originally posted by Giskard
Ralf,

Looks decent. Are these 12 cubic foot volumes?

Paul D,

Sealed enclosures can also result in boominess if the sealed volume is too small for a given trasnducer (Qtc ~> 1.2). Vented enclosures are harder to "get right" hence the common misbelief that they are all boom boxes. They CAN be boom boxes, but they don't HAVE to be.


hi,
perhaps giskard can tell us if it's possible to use jbl bx 63 to extend bass response. perhaps he can give us schematics of this network :D

4313B
11-13-2003, 11:18 AM
Ralf,

Looks decent. Are these 12 cubic foot volumes?

Paul D,

Sealed enclosures can also result in boominess if the sealed volume is too small for a given transducer (Qtc ~> 1.2). Vented enclosures are harder to "get right" hence the common misbelief that they are all boom boxes. They CAN be boom boxes, but they don't HAVE to be.

4313B
11-13-2003, 11:31 AM
Originally posted by delahais
hi,
perhaps giskard can tell us if it's possible to use jbl bx 63 to extend bass response. perhaps he can give us schematics of this network :D
I've posted schematics of the BX63 and BX63A numerous times. I've also uploaded the BX63 response for those who use BB6P. I've posted how to remove the low pass filter in the BX63, leaving just the EQ. You should be able to find the threads doing a search for BX-63 or BX63.

If you want to try a fun little LF EQ try this - Eight Band Sub-Woofer Graphic Equaliser (http://sound.westhost.com/project84.htm)

He has other fun projects as well...

The top designers at JBL are not shy about using EQ. The latest crop of transducers such as the ME150HS, 1500AL, 1400ND, 1500FE, 2242H, etc. respond quite well to some LF and VLF EQ.

Ralf
11-13-2003, 03:18 PM
[QUOTE]Originally posted by Giskard
[B]Ralf,

Looks decent. Are these 12 cubic foot volumes?

Hi Giskard,

Yes, each box has exactly 12.143 cubic foot.

Dimensions External:
(HxWxD)
1189 x 754,1 x 485,1 mm

Wall Thickness 25 mm MDF

Port Diameter 222 mm
Port Length 538 mm (must be bent)

4343mod
11-13-2003, 03:32 PM
Amazing thread. I'm compressed. Way out of my league.

Niklas Nord
11-13-2003, 03:35 PM
Since i have 4 of the 2245 and 4 of the 2235, there are really
SOME things i could do with these..

corner placed, and i tend to buy a TacT, so sealed boxes whaaa

:smthsail:

delahais
11-14-2003, 03:16 PM
Originally posted by Giskard
I've posted schematics of the BX63 and BX63A numerous times. I've also uploaded the BX63 response for those who use BB6P. I've posted how to remove the low pass filter in the BX63, leaving just the EQ. You should be able to find the threads doing a search for BX-63 or BX63.

If you want to try a fun little LF EQ try this - Eight Band Sub-Woofer Graphic Equaliser (http://sound.westhost.com/project84.htm)

He has other fun projects as well...

The top designers at JBL are not shy about using EQ. The latest crop of transducers such as the ME150HS, 1500AL, 1400ND, 1500FE, 2242H, etc. respond quite well to some LF and VLF EQ.

hi GISKARD,
thank you, interesting !:thmbsup:
regards.

pdemondo
11-17-2003, 02:21 PM
I have a couple of Phoenix Gold Cyclones each in
a 6 cubic ft. (net) enclosure (cubes) firing down. There is
1 15 in Stryke audio passive radiator on each side
box tuned to 16 hz. (2 PR per box).

I can rattle my foundation and communicate with
whales. for 30hz and up about 10 Watts is fairly
loud. I max out the PRS at 15 hz , I am adding
2 more and tuning to the same freq.

Most of the time the addition to the mains is very
subtle. My subs only put out from 50 hz on down.
(Using active crossover).

I couldn't afford the contrabass so I went this route.

Niklas Nord
11-24-2003, 02:03 PM
Then, to get rid of boominess, there should be interesting to
try selaed boxes? :smthsail:

pdemondo
11-25-2003, 01:40 PM
Well boominess is not really a problem.
(I could just be a bass nut)
I started out with sealed boxes but I could
reach their limit with Jurassic Park III. I figured
I would add PRs tuned low (turned out to
be 16hz) to take the low end work away
from the cyclone.

Also, I didn't think the subs were sensitive enough
on the bottom end.


I am powering the subs with a Pioneer Spec 1
amp. Its output starts to drop below 20hz.
I also use the Spec 2 preamp for volume
adjustment of the sub. I feed the subs with
a DOD electronic crossover set to about 50hz.

My house is open so the sound plays into about
2000 or so sq. ft of my house.

With the PRs I get noticeable 35 hz - down reinforcement.

Since I have tuned so low, I can't notice delay from subs
vs. mains (250Tis). It sounds tight.

More than anything, with the PRs, I really notice impact
on music much more that doesn't seem to be coming
from the subs. When you turn the subs off the
impact diminishes. (Impact less "full-bodied")
(MY AB comparisons).

The 1812 Cannon fire sounds real. Thunder is
quite enjoyable as well.

I kept the holes I cut out (used a thin router bit) just in
case I decided to reverse course, but I was surprised
I think it works well.

The cyclones seem to be just right for the 250Ti's, they help
in the 30hz on down range.

The hardest part is there are no T/S parameters to deal with.
I have been using trial and error for about a year or so and
I think I am almost there.

I have cut and rounded solid teak edges and have started
applying the teak veneer. The "look" like the TI's in grain.
the tone of my veneer is more brown, the Tis are a little
more towards red. When they finally look like furniture,
I can post some pics.

Niklas Nord
11-25-2003, 02:23 PM
Sound great.

Ralf
12-01-2003, 04:19 PM
I play arround with some considerations. Has anybody build a Compound-Box with 2245H?

Ok. the pressure goes down, but the kick in the near of 20Hz is interesting...(theoretical software results)

4313B
12-01-2003, 04:30 PM
That I haven't tried...

Ralf
12-01-2003, 04:35 PM
Originally posted by Giskard
That I haven't tried...

Is there any reason why not?

4313B
12-01-2003, 05:11 PM
I never had the need.

What is the "real estate" cost we are talking about here?

Ralf
12-02-2003, 01:37 AM
Originally posted by Giskard
I never had the need.

What is the "real estate" cost we are talking about here?


Ok. the discussion about optimized acustic rooms and their costs is maybe a theme for a new thread...

Look at my rough draft. What is if the chassis and the vents are not on axis? Is their any problem?

Ralf
12-02-2003, 01:46 AM
...and here the theoretical frequencies:

Niklas Nord
12-10-2003, 08:43 AM
Tim G:
"Using Unibox, with a pair of 2245H in sealed boxes with at least 4.8 cu ft per driver, I get 104.5 dB at 16Hz at 1M, before room gain, at xmax. If you your room has rigid walls and you place the drivers together in a corner I would expect at least 112dB at 16Hz.

With 4 drivers you are looking at 110.6dB anechoic at 16Hz. THis would give you close to 120dB with room gain. You would be hitting 120dB anechoic at 27.8Hz.

These models do not account for driver compression and it does not tell me how much power it takes to hit xmax."



Can this really be true, can the 2245 really reach souch
high output in a sealed enclousure? IF thats so, then i
vill absolutely try selaed..

Ralf
01-08-2004, 09:12 PM
To get really 16 Hz it is a Problem with Power compression....so I downgrade to 20Hz...but this is possible with enough sound pressure...my computations resulted in the following:

- Together with my system (2x4530/2226H + 2x2206, 2x2344/2426J, 2x2404) 20Hz can be only reached, if 4 2245H-18"-Speakers are used (cutoff 50-60Hz).

The following conditions are to be considered:

- maximum sound pressure adapted to the 4530

- maximally linear frequency characteristic down to 20Hz

Here is the solution:

4 x vented enclousures
(housing with the following dimensions (25mm MDF):

Width x Depth x Height
573mm x 673mm x 1036mm

3 Ducts:
outside dia. meters of 100mm,
inside 93,7mm,
length 314mm

Pictures will follow...

Greetings
Ralf

Ralf
02-11-2004, 07:39 PM
I purchased today the third 2245H chassis.

Soon is it so far...

mikebake
02-11-2004, 08:44 PM
Ralf rocks!!

Ian Mackenzie
02-11-2004, 10:29 PM
Have you tried any B6 alignments, the advantage is less real estate and control of cone excursion at Fb and below.

At the risk of being exciled, for anything below 25 hertz you may well be better looking at a Bad End Sub or a Profounder which uses parametric loading to extend and control cone movement, both these have Lucas Certification.

With such attempts to get a loe F3 you sacrific too many other performance critieria in my view and is unlikely to sound good on normal program sources.

Ian:banghead: :rotfl: :rotfl: :rotfl:

mikebake
02-12-2004, 07:27 AM
I'm with Ian; demanding to get that low does entail a different beast with some design compromises. Given that room reinforcement can lower the response anway, why kill yourself going after it?

Guido
02-12-2004, 07:40 AM
Originally posted by mikebake
Ralf rocks!!

He does and I know him:D

Ralf
02-12-2004, 08:09 AM
Originally posted by mikebake
I'm with Ian; demanding to get that low does entail a different beast with some design compromises. Given that room reinforcement can lower the response anway, why kill yourself going after it?

I give you quite that room resonances and interferences are a problem.

In addition, one can get that into the grasp.

I build now the test boxes and everything else arise. For each problem there is one solution at least. That applies to all situations in life and problems.

We`ll see.

4313B
02-12-2004, 09:03 AM
If you have an 8 cubic foot space available and you want the kind of 16 Hz bass response that literally busts stuff up in your place of residence fill the 8 cubic feet with four JBL 121H's and let 'em rip. No stoopid servos or goofy assed electronics bullshit. No smoke or mirrors. No ports, no ducts, just sealed boxes, mutual coupling, and a 12 dB/octave low end roll off which any decent room should counter with it's rising response reasonably well.

Be forwarned that you will be repairing your place of residence. You will replace plate glass picture windows and lamp filaments and broken plaster and expensive china :blah: :blah: :blah: The tired old phrase "been there, done that" pretty much sums it up. Going that low is just too damn damaging to everything in the vicinity.

Ralf
02-12-2004, 09:04 AM
Originally posted by Ian Mackenzie
Have you tried any B6 alignments, the advantage is less real estate and control of cone excursion at Fb and below.

At the risk of being exciled, for anything below 25 hertz you may well be better looking at a Bad End Sub or a Profounder which uses parametric loading to extend and control cone movement, both these have Lucas Certification.

With such attempts to get a loe F3 you sacrific too many other performance critieria in my view and is unlikely to sound good on normal program sources.

Ian:banghead: :rotfl: :rotfl: :rotfl:

When the testboxes are ready I`ll motify a 5235 like Giskards manual for a +6dB bump filter. Then it really rocks...

Ralf
02-12-2004, 09:11 AM
Originally posted by Giskard

Be forwarned that you will be repairing your place of residence. You will replace plate glass picture windows and lamp filaments and broken plaster and expensive china :blah: :blah: :blah: The tired old phrase "been there, done that" pretty much sums it up. Going that low is just too damn damaging to everything in the vicinity.

I look forward to it and will be pleased...

4313B
02-12-2004, 09:11 AM
Ok, if you want to do the B4 to B6 trick then just build your 8 cubic foot volumes for each 2245H and put two ports in each volume. Tune the volumes to 28 Hz using the two ports. When you want DVD movie playback instead of music playback block one of the ports (lowers the tuning by Keele's recommended amount to 20 Hz) and kick in the +6 dB boost at 20 Hz.

Again... "been there, done that, it was fun". :yes:

*****

Unless you get real nutty with the volume, the roll-off from the 6 dB bump filter in the 5234A/5235 should keep you from blowing the cones of the 2245H out onto the floor with sub-20 Hz program information.

Ralf
02-12-2004, 09:48 AM
Originally posted by Giskard
Ok, if you want to do the B4 to B6 trick then just build your 8 cubic foot volumes for each 2245H and put two ports in each volume. Tune the volumes to 28 Hz using the two ports. When you want DVD movie playback instead of music playback block one of the ports (lowers the tuning by Keele's recommended amount to 20 Hz) and kick in the +6 dB boost at 20 Hz.

Again... "been there, done that, it was fun". :yes:

*****

Unless you get real nutty with the volume, the roll-off from the 6 dB bump filter in the 5234A/5235 should keep you from blowing the cones of the 2245H out onto the floor with sub-20 Hz program information.

I`m a little bit confused about the 8 cubic foot box. With BBP I got a better result with 12 cubic foot. Did I survey something? Or are there still different reasons for it?

4313B
02-12-2004, 10:40 AM
12 cubic feet can work. Make sure you look at the whole package. What was the initial tuning frequency you decided on for the 12 cubic foot enclosure? How does it affect power capacity and acoustic output? Group delay? When you kick in the +6 dB boost filter the total group delay can potentially double, even triple. Not necessarily a problem when playing a movie but definitely a potential problem with music playback, especially with such types as classical, orchestral, or chamber music.

Niklas Nord
02-12-2004, 11:20 AM
My 14 cubic feet box is tuned to 14,5hz :D :smthsail:

Ralf
02-12-2004, 11:24 AM
Originally posted by Niklas Nord
My 14 cubic feet box is tuned to 14,5hz :D :smthsail:

Hi Niklas,

How is the result? Do you have 4 of these?

Niklas Nord
02-12-2004, 11:27 AM
I have not been testing them yet.
if it sounds bad, i can always cut the ducts

Ralf
03-08-2004, 06:37 PM
now i found the last 2245H...I will beginn now...

mikebake
03-08-2004, 08:11 PM
Originally posted by Giskard
Ok, if you want to do the B4 to B6 trick then just build your 8 cubic foot volumes for each 2245H and put two ports in each volume. Tune the volumes to 28 Hz using the two ports. When you want DVD movie playback instead of music playback block one of the ports (lowers the tuning by Keele's recommended amount to 20 Hz) and kick in the +6 dB boost at 20 Hz.

Again... "been there, done that, it was fun". :yes:

*****

Unless you get real nutty with the volume, the roll-off from the 6 dB bump filter in the 5234A/5235 should keep you from blowing the cones of the 2245H out onto the floor with sub-20 Hz program information.

So, Giskard, what happens on my 2245 cabs if one port is blocked??
Anyway, last night my sister is over, having dinner upstairs; the kids are watching Monsters, Inc. on the big screen; I had it at "normal theater levels" and in one sequence during the movie, I was walking in the living room upstairs and "WHOOOOMP" came from below and you could not just feel the floor shake, as in many subs, but, like MOVE upwards.................weird............
Anyway, so far I like them the way they are. What a great driver, the 2245.

4313B
03-08-2004, 09:08 PM
The tuning frequency will drop to around 20 Hz and you can then add a +6 dB bump filter at 20 Hz using a network like the 5234A/5235.

I've done both and prefer the non-EQ'd version in general but you might like it for movies.

Watch the Disney movie Atlantis. Find the track where the Leviathan attacks ;)

Ralf
04-16-2004, 12:16 PM
Next week the 4 cabinets are ready and I will beginn to install the drivers.

I have to recone two of the 2245H before...

Pictures will follow....

I am strained, as they get along with my 4530.
Possibly it does not sound. I have however still two 2235H remaining....

Ralf

Steve Schell
04-26-2004, 10:42 AM
Being a front horn loaded kind off guy (hick!) I took a different approach to covering the bottom two octaves. I built a 15Hz. flare exponential horn sub which uses a single 15" driver (Altec 515-16G) and a split, W bin style 20 foot internal horn path. The enclosure is roughly 8' by 8' by 2', and stands on end against a wall and exhausts out the side. When the mouth is placed 4' from a corner, the corner becomes the final bend in the flare and the room maintains the flare expansion quite well out to 35' or so total path length.

I've been very happy with the results. Sensitivity is about 107dB, and the -3dB point is 20Hz. To me the results sound cleaner and more dynamic than any direct radiator subs I have heard, or horn subs with a short flare and EQ bump on the low end. The downside of this design is the low Spouse Acceptance Factor, and the 20 millisecond delay due to the path length. I am about to try dialing this delay out through digital means.

boputnam
04-26-2004, 11:05 AM
Originally posted by Giskard
Watch the Disney movie Atlantis. Find the track where the Leviathan attacks ;) Or, since we're on a kiddie theme... Watch "Finding Nemo" and play the track where the submarine is slipping off the reef edge into the abyss. :rockon2:

Ralf
05-11-2004, 11:05 AM
here are some pics from the project...

Ralf
05-11-2004, 11:06 AM
.

Ralf
05-11-2004, 11:09 AM
.

Guido
05-11-2004, 02:04 PM
Good God!

I start to feel that "after soundtrack ringing" in my ears.
:D :D :D

Ralf
05-11-2004, 02:20 PM
you will not get a ringing with that...you will get vibrations...


Originally posted by Guido
Good God!

I start to feel that "after soundtrack ringing" in my ears.
:D :D :D

andresohc
05-11-2004, 05:44 PM
Those look great!, I have a 4518 enclosure that looks like an ugly version of yours (beat up pro cabinet). It has the same three vents, designed for the 2245h. The JBL tech sheet says 4518 is tuned for 30 hz, I havent read this thread lately and forgive me if you posted this, but whats the volume of the enclosures and the size of the ports. I actually wanted to try and tune my 4518 enclosures to closer to 20 Hz

Are the clamps for the veneer, are you using finished one side plywood or did you veneer the mdf? Man, the one who dies with the most clamps wins
Nice setup.:D

Ralf
05-11-2004, 07:15 PM
Hi andresohc,

here is an excerpt of this threats:

[ Maybe I have a solution....

To get really 16 Hz it is a Problem with Power compression....so I downgrade to 20Hz...but this is possible with enough sound pressure...my computations resulted in the following:

- Together with my system (2x4530/2226H + 2x2206, 2x2344/2426J, 2x2404) 20Hz can be only reached, if 4 2245H-18"-Speakers are used (cutoff 50-60Hz).

The following conditions are to be considered:

- maximum sound pressure adapted to the 4530

- maximally linear frequency characteristic down to 20Hz

Here is the solution:

4 x vented enclousures
(housing with the following dimensions (25mm MDF):

Width x Depth x Height
573mm x 673mm x 1036mm

3 Ducts:
outside dia. meters of 100mm,
inside 93,7mm,
length 314mm

Pictures will follow...

Greetings
Ralf


QUOTE]Originally posted by andresohc
It has the same three vents, designed for the 2245h. The JBL tech sheet says 4518 is tuned for 30 hz, I havent read this thread lately and forgive me if you posted this, but whats the volume of the enclosures and the size of the ports.
[/QUOTE]

Ralf
05-12-2004, 04:17 AM
Originally posted by andresohc

Are the clamps for the veneer, are you using finished one side plywood or did you veneer the mdf? Man, the one who dies with the most clamps wins
Nice setup.:D

I have veneered the mdf with walnut wood. I use the clamps to glue the plates correctly. It is difficulty, because the plates are cut approximately in the 45 degree angle. So I need a lot of clamps...

dieterj
05-12-2004, 02:38 PM
Very nice Enclosure, Ralf!

Dieter
:cool:

Robh3606
05-23-2004, 01:52 PM
How about a 2245 in one of these???:rotfl:


Rob:)

Ralf
05-23-2004, 02:37 PM
Originally posted by Robh3606
How about a 2245 in one of these???:rotfl:


Rob:)

YEAH !!! That`s it! Thx for this great idea!!!:banghead:

Ralf:thmbsup:

Audiobeer
05-23-2004, 06:42 PM
Originally posted by Ralf
.


Nice Shop Ralf! What the hell is that room for industrial production or fun? Nice !!!

Ralf
05-23-2004, 09:32 PM
Originally posted by Audiobeer
Nice Shop Ralf! What the hell is that room for industrial production or fun? Nice !!!

Fun! Not more... That is the production hall for our (Guido`s and Ralf`s) crazy stories....

Those are the premises of a friendly carpenter, who likewise loves such cabinets...

Ralf

Audiobeer
05-23-2004, 09:46 PM
Your a lucky man! I ended up contracting to do repairs on neon signs for Anheuser-Busch in my area, so I ended up clearing out all my woodworking stuff (Hobby). I really miss going out there and losing myself in a furniture or cabinet project! :banghead:

Ralf
05-24-2004, 01:15 PM
Originally posted by Audiobeer
Your a lucky man! I ended up contracting to do repairs on neon signs for Anheuser-Busch in my area, so I ended up clearing out all my woodworking stuff (Hobby). I really miss going out there and losing myself in a furniture or cabinet project! :banghead:

Then you have now infinitely much time. Simply do it...

mikebake
05-24-2004, 08:11 PM
Originally posted by Robh3606
How about a 2245 in one of these???:rotfl:


Rob:)

Or in THIS

http://www.roger-russell.com/truth/truth.htm#norelco

Jakob
05-25-2004, 02:52 AM
Hi Ralf, nice work!

Im about to start building a couple of 2245 test boxes for use with my 250 ti:s. If I'm satisfied with the result I will maybe try to build two B460's. But if that turns out to be too much for me, then I'll have to veneer the testboxes to be allowed to keep them in the house. Where did you get hold of your veneer, and were there different kinds of wood as teak f.e.?

b.r: Jakob

Ralf
05-25-2004, 10:29 AM
Originally posted by Jakob
Hi Ralf, nice work!

Im about to start building a couple of 2245 test boxes for use with my 250 ti:s. If I'm satisfied with the result I will maybe try to build two B460's. But if that turns out to be too much for me, then I'll have to veneer the testboxes to be allowed to keep them in the house. Where did you get hold of your veneer, and were there different kinds of wood as teak f.e.?

b.r: Jakob

Hello Jakob,

I think it`s difficult
the veneer is American nut tree. One can order that here over wood wholesale dealers.

In principle each hardwood is to be gotten as veneer.

Ralf

Ralf
08-31-2004, 03:31 PM
.

Ralf
08-31-2004, 03:33 PM
.

4313B
08-31-2004, 04:15 PM
Go-Gee-Dah!

Zilch
08-31-2004, 06:48 PM
[Out go the lights!] :bouncy:

mikebake
08-31-2004, 08:41 PM
Ralf. way to go! Those are GORGEOUS!

Guido
09-01-2004, 04:15 AM
This is it
:jawdrop:

Robh3606
09-01-2004, 05:33 AM
WOW very nice work!!

Rob:)

Ralf
09-27-2004, 07:11 AM
I`m surprised. Today I got a special test cd with
different frequencies. I drive 2 of the 4 2245H and got 16Hz....That`s it.

4313B
09-27-2004, 07:34 AM
Okie Dokie!
Quest Complete! :)

paragon
09-27-2004, 07:55 AM
There is a pair of Magnat behind ?

Eckhard

Ralf
09-27-2004, 09:43 AM
Puaaaahh,

no magnats needed. JBL is able to go for it.

Ralf

paragon
09-27-2004, 09:55 AM
But what do you do with this ??

Eckhard

Ralf
09-27-2004, 10:02 AM
Originally posted by paragon
But what do you do with this ??

Eckhard

with what?

paragon
09-27-2004, 10:39 AM
Doen`t think bad about Magnat.
Look at Ebay what they get for their "Ribbon Series".
I get an old pair of Superbull II (mid 70`s) and they sound
very good. Alnico magnets on the low drivers !!
Look !!

paragon
09-27-2004, 10:47 AM
The sidewalls are made of 3 !! cm sandwhich wood.
And the front and back are made of 2 cm wood.
Is that bad ??
The front is also fixed with a samt(?) cloth.
Is this bad??

Eckhard

Ralf
09-27-2004, 11:26 AM
Originally posted by paragon
The sidewalls are made of 3 !! cm sandwhich wood.
And the front and back are made of 2 cm wood.
Is that bad ??
The front is also fixed with a samt(?) cloth.
Is this bad??

Eckhard

sounds good, Eckhard. Nobody has said something bad about Magnat...

paragon
09-27-2004, 11:46 AM
Yes,
You are right !!

Eckhard

spkrman57
03-14-2005, 11:04 AM
WOW!!!

I remember when I first recvd my 4648's from the tent sale(JBL pro) and set them up hozontially on the floor/wall boundry and used Rane AC-22 crossover set for low-pass 120hz on the 4 2226J's in 4648 cabs.

I powered them with a Carver TFM-35 (250 watts/chnl) to break them in. I played all kinds of music(mostly non high quality music unfortunately).

I have a 12' X 16' living room with 8 ft ceiling. I went outside to see how much sound was leaking out to the world outside( my neighborhood).

I felt the stucco exteriorer outside the house, came in and shut down the system, and that was the last time I had a quad of 2226's running hard in my house.

I know some of you out there are wondering why I am getting 2242's to run in my house. Well my normal listening is not that loud, and other than breaking in the 2242's, I will not run at "home-destructive" levels.

It will be a rough time breaking those 18" 2242's in as I am only using 75watts/chnl at 80hz on down to mesh with my Edgarhorns. The midbass horn is only good down to 80hz, hence the subs to finish off the bottom octave.


I found a really interesting point that was brought up in this thread that I totally forgot about. Lowering the tuning frequency by plugging up on of the ports in my cabinets. I no longer have anything more than 250 watts in the house anymore(tube amp junkie), and those are sub-plate amps. My next in line amp is the Sansui AU-7900 I just had reworked and modded recently(75wpc).

Thanks to all in this intruiging discussion, it goes to show the search function will give you tons of info if you use it!!!!!!

Ron