gene's speakers - cabinet tuning, crossover and more!

[gene]

hey guys. I never wanted to say this but I think my speaker cabinet are not tune right.I get some bass but not the way I thought I would. does any one know a company or some one who tune speaker cabs. My speakers are jbl 2245h -2202h -2425h-2404h. the cabs are 54 height- 24 witdh- 19 deep. I was told the ports should be 5 inch diam - 5 5/6 inch long that should be tune around 26 hz. the cabs are birch wood 3/4 thick thanks for any info gene

[Zilch]

One port per cabinet?

You should measure your current box tuning. Do you have a tone generator or test-tone disc?

[Robh3606]

What's the internal volume minus bracing, drivers, and subenclosure for the 2202. If the horn is internal on the 2425 which one are you using. You need to subtract that as well.

Rob:)

[boputnam]

Dood...

Everytime you post problems with your DIY build, you ignore my questions - yet you keep returning here unhappy. :(
I am not trying to be rude, but answer some detailed questions - OK?

Here, you describe Your Cabinet Dimensions you mention a 12-ft3 volume. That is large for a 2245, depending upon your tuning. You ignored my question on what the tuning was. Do you know what it is?

I also wonder if your 2202H is NOT in a separate subenclosure (bad), but you only post coarse dimensions of your cabinet

the cabs are 54 height- 24 witdh- 19 deep.
and then pm Ian for help.

That is fine, but dood, you are drifting and wasting all the combined talents here.

DESCRIBE YOUR CABINET BUILDS IN DETAIL, or we all join you in pissing up a rope... :o:

[Ian Mackenzie]

I hope it works out better than my last encounter with a 4 way diyer.

Gene,

My I ask why you think they are not tuned right? :D Can you describe what you are hearing? Is it biamped? :D Please tell me it is :biting:

The cat might be sleeping in the Port:blink: ..No kidding is happens!:p

The Vas is so large compared to the box volume Vb that some small variation will not upset it to much. More likely the vent will need some adjustment.

My last recollection of a box tuning Fb for that driver around 10-11 cu ft was 27 hz.

Give me a picture of what you have

Thanks

[Ian Mackenzie]

Dood...

Everytime you post problems with your DIY build, you ignore my questions - yet you keep returning here unhappy. :(
I am not trying to be rude, but answer some damned questions - OK?

Here, you describe Your Cabinet Dimensions you mention a 12-ft3 volume. That is large for a 2245, depending upon your tuning. You ignored my question on what the tuning was. WHAT IS IT?

I also wonder if your 2202H is NOT in a separate subenclosure (bad), but you only post coarse dimensions of your cabinet

and then pm Ian for help.

That is fine, but dood, you are drifting and wasting all the combined talents here.

DESCRIBE YOUR CABINET BUILDS IN DETAIL, or we all join you in pissing up a rope... :o:

What combined talents are they.


Auto sub change outs are your speciality.

Gene, take no notice of Bo. He who knows not the difference of an Oval and a Round Port:D

[Mr. Widget]

I never wanted to say this but I think my speaker cabinet are not tune right.I get some bass but not the way I thought I would.We really could use some additional info... are your cabs actually 12 cu ft or are there sub chambers, bracing , etc. to be subtracted. If there isn't quite a bit of bracing then you could be losing a lot of bass energy due to wall flexing. This will muddy the sound as well as lower the SPL and extension.


Widget

[Don Mascali]

This is an amazing little thing.


http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=390-802&CFID=644999&CFTOKEN=24432096

[boputnam]

This is an amazing little thing.It was reviewed to some extent here: Woofer Tester II

But, it would be handy if gene came back with some detail on his cabinet construction, and maybe a few pics, too... :)

[Ian Mackenzie]

One thing I noted was the 2245 is used with a passive network. That will effect the bass quality for certain regardless of what amp or tuning he tries.

[gene]

when I post my problem yesterday I was madd. and I gave the wrong info on the cabs.the right measurements are 54 inch tall- 29 inch wide- 19 inch deep. the 2202 is in a seald cab . about 14 wide 14 tall and 8 inch deep. the cab is birch wood 3/4 thick. the horns are mounted on the front of the speaker cab with weather proof sponge like materials. no air is coming from the side of my horns. cross over is passive 290 hz 1200 -5000. xover is not biamp. ports are two ports per cab 5 inch diam- 5 5/6 inch in lenth they suppose to be tune around 27 hz. they have bass but not like the L112 or L56 If I stand to the side of my speaker I can her more bass but if I stand in front of them the bass is less. the guy how gave me the ports measurements said he took my in side measurements of my cab and my 2245 vas qmax etc.and he came up with the ports measurements the cabs do have brace , in the middle of the cab were the seald box is for the midrange and some kind of brace in each corner of the speaker cab I hope I answer all of your question . 2344a birdal horn is mounted to the 2425h

[boputnam]

:applaud: Yea, we are starting to get somewhere!!

gene - is there any way you can post some pictures? It would be nice to see the overall cabinet shape / configuration.

Also, try and get some close-ups of the 2245H - how new are they?

How are the cabinets sealed? Any chance of leaks out the rear, or anywhere else?

[boputnam]

:idea:

Is it possible to get your cabinet maker and crossover designer to get involved in this discussion? You likely paid dearly for those cabinets and they should be willing to help. Maybe they can join here...

The more information you can get to the forum, the more efficient help you will receive.

It would be great to get those beauties working up to par!

[gene]

I just finish sending [email protected] my picture of my speakers. I hope they post them. my xovers were built by dssoundlab.com. the xover is pretty big it is rated 600 watts rms at 8 ohms 95 db at 1 watt. I will try to get dssound and the company who build my speaker cabs to respond to your questions. thanks . gene

[Zilch]

BB6P computes your gross internal volume at 14.62 cuft and 13.38 cuft net after subtracting the woofer displacement and the subenclosure.

It indicates you are presently tuned to 25.93 Hz (black), not a bad tuning, actually. It's -3 dB at 30.59 Hz, and should be producing plenty of good bass.

It further suggests for more extended bass, you might retune to 21.22 Hz (orchid) with two 5" ports 11.85" long, or a single one 3.375" long. That'd give you usable bass down to 19.24 Hz (cursor).

To try a similar lower tuning, just close off one of your present ports. That'll retune the box to 19.07 Hz (red).

I'm thinking if L112 and L56 comprise your standard for comparison of bass performance, you're not going to like any of these extended bass tunings, but give it a try.

Further, without measurements, it's not known if the drivers are in balance. I could easily see how the 2202H must be properly balanced with the 2245H, for example, for that combination to sound right....

29" wide, not the 24" you originally posted above, right? 24" gives the 12 cuft. you previously stated they were. :blink:

Note: If I just let BB6P design the box for extended bass, it recommends 15.46 cuft tuned to 20.76 Hz for the 2245H (blue).

For "High Fidelity" (maximally flat) tuning, it says 7.95 cuft tuned to 26.45 Hz (green).

What you presently have seems a good compromise. :dont-know

[gene]

Thanks for the info on the ports zilch. they are no l-pads at all on the 2202 2425 2404. www.dssoundlabs.com (http://www.dssoundlabs.com). he use some kind of soft ware on his computer that with the right type of caps -iron core what ever, it would tune all my driver to 95 db at 1 watt. If you go to his web site and click on quilty first then go down to edc-crossovers ,It would explain a little about his balance tuned crossovers

[gene]

hello boputnam. the cabs have some kind corner brace in each corner inside the cab. and they use hot glue. the cabs are pertty air tight. on my lunch break and after work I would stop pass the shop in check out my speaker every day

[Zilch]

Gene, I need for you to clear up the width issue. Are they 24" or 29" wide?

[Ian Mackenzie]

Hi Gene,

Thanks for your post..we wondered where you had got to.

Is the main enclosure lined with fibreglass?

In my initial I tuned with the 2245 I usedthem in a similar manner to yours but I used an active crossover (DB Keele tuning 292 litres 27 hz Fb).

Using the passive crossover later on made the bass less tight and a bit boomy.

The reason is that the effect of DC resistance in the crossover for the woofer and the large box gives a somewhat underdamped response and will lead to a small bump in the response.This is because the wooker T/L electrical and mechanical paramters are effected and this leads to audible ripple an or a slight lift in the response.

Is this what you are hearing?

In the commercial JBL systems, they tuned the 2245 at 30 hz and use a smaller box. In the JBL monitor 4345 the net volume is 9 cu ft and its tuned to 28-29 hertz.

I find the biamping on this woofer far more satisfactory than a passive crossover.

regards

Ian

[speakerdave]

Maybe Gene has room/placement problems like the other guy (investment biker) who said his little speakers sounded bassier.

[Ian Mackenzie]

Ah yes but has Steve G says..and I will always remember this ....we should not speculate until we are told what he is actually doing. of course he might not know such:barf:

[johnaec]

he use some kind of soft ware on his computer that with the right type of caps -iron core what ever, it would tune all my driver to 95 db at 1 watt.If it's only the bass that's lacking, I'd suggest bi-amping the cabinet - it almost sounds like his crossover calcs are off re: efficiency of the 2245H vs. level matching the other drivers.

John

[gene]

Hello.zilch the cabs are 54 tall -29 wide and 19 deep. Ian I have the cabs insulated with fiberglass.

[Ian Mackenzie]

Gene,

Can you post a picture inside and outside the box and its location in your room?

Can you also advise if you had you boxes built and tuned buy the cabinet builder?

Can the builder tell you any specifications about the tuning?

[Ian Mackenzie]

Gene,

Based on the limited information provided I doubt if there are any serious errors with the tuning.

Its more a case of what has been arranged and whether this tuning suits your needs and taste.

Technically, given the box net vol is about 12-13 cuf ft (from what you say) the tuning of the ports as stated will be somewhere in the vacinity of 27.5-26 hertz depending on the actual net volume.

However +- 2 hertz either way will give an acceptable result.

Subjectively, my inclination is that the tuning that you have currently looks good on paper but it is set up for a subwoofer for use below 80 hertz because as previously advised this will offer a degree of extended response at the cost of some group delay.

To explain , with your current tuning the -3 db point is 27.5 hertz (+- 5 % which I would not loose sleep over) assuming a 12 cu ft box with some 21 ms group delay at the tuning frequency according to my simulator. The group delay is quite possibly more if I include the effects of fill (QL) and the effect of the woofer crossover choke on the total Qts of the woofer.

Fill incidentally makes the box appear a bit bigger to the woofer. It also absorbs some of the energy from the woofer.

So I think its a borderline scenario you have for getting a tight articulate bass sound based on my own practical experience. Therefore I would tend to steer clear of any extended bass alignments in your application.

Moreover as you are crossing over the 12 inch driver at a higher crossover the subjective result may not be entirley satisfactory, particularly as you have a passive crossover arrangement. The bass will tend to lag the lower mid/bass region covered by the 12 inch driver .

My suggestion is to experiement with some alternative tunings by reducing the net volume with an intert (with the heads of a couple of forum members..a joke:D ) solid substance and retuning the box to say a net volume of 10 cu ft @ 30 hertz, or even less volume say (three forum members heads:D even more funny) 9 cuft @ 28.5 hertz. The later will still provide an F3 of 32 hertz but less group delay

The subjective bass quality will change and will tend to sound more articulate and defined. You need to decided what you like best.

For you own interest JBL used empirical tuning to arrive and what they felt was the most desirable tuning for this woofer in their studio monitors and I find this offers me the best performance.

Gene, please don't loose any sleep over this sort of thing. Just try some of the above options and see how you go.

Pm me if you need more detailed assistance!

Ian

[boputnam]

via email:

"I will take some of xovers and inside of cabs. gene"

[gene]

hello guys. Ian I just found my paper work on the cabinet tunings the right measurements are 4 inch in dia and 5 5/6 in lenth. I just took a ruler and measure the ports size. the company who build my speakers just build any thing made out of wood. madd sound gave me my ports measurements

[gene]

Thank you Mr BOPUTNAM for helping me post my speakers gene. The ports are located at 11 and 2 ocolck at the top of the woofers but you cant see them. sorry about the wrong info I gave all of you early. the speaker size is 54 tall -29 wide -19 deep. ports are 4 inch in dia and 5 5/6 inch in lenth. I spoke to dssoundlabs, Ian he is going to build me a biamp xover. I spoke with the company who build my speakers and he said they used something called biscuits and blocking? but were the midrange is located there is a brace in the middle of in side of the cabinet

[gene]

To Zilch I know I told you my ports were 5 inch in dia 5 5/6 in lenth I was wrong and I apoligize I measure them this eving .they are 4 inch in dia and 5 5/6 in lenth:) I spent a lot of money on these speakers which money is one thing I really dont have. I have two keds and a girl friend who works p/t I been saving this money for a long time. I not looking for crazy bass but good bass I dont have a problem with the mids/ or highs I just want to be proud of my custom jbl speakers and brag about them just a little. I dont want to for get every one who help me so thank you all

[Zilch]

It's O.K., Gene, but before I run the calcs again, please verify that the port length is 5-5/6". That's an odd way to express the length, as few scales read in 1/6".

Decimal equivalent is 5.833", just over 5-13/16", but less than 5-27/32". Is this correct?

[Mr. Widget]

It's O.K., Gene, but before I run the calcs again, please verify that the port length is 5-5/6". Don't you imagine that's a typo... 5 5/16"?

Sounds like you have really underbraced cabs... those are quite large boxes to only have a couple of braces in the middle.

Other issues:

How much and what type of damping material is inside?
Only one 4" port for an 18" sub?! At any SPL above a whisper you will hear port noise at low frequencies.

My guess is that you have a very lossy cab that is tuned too low. You may also have room placement issues.


Widget

[Ian Mackenzie]

I tend to agree with The Widget.

While you recent measurments are more factual, I think my previous thoughts posted earlier about the tuning apply.

Gene, you mention something about the woofer supplier giving you the tuning. I think they have given you tuning based on an understanding/assumption that this was a sub woofer application.

There have been several articles written about this driver for sub woofers using 12 cu ft 3 enclosures. In each instance operation above 80 hz is NOT recommended. If my understanding is correct you are operating the woofer over a bandwidth up to 250hz. This really necessitates a different type of alignement.

All is not lost but it is most likely you will require alternative tunings as i explained earlier.

The closest tuning given the current enclosures is a Keele alignment of 292 lites (about 10.3 cu ft) tuned to 27.2 hz. The two 4 inch ports will need to be in the order of 4 1/4 inches in length. This assumes Ql=7 and normal filling in Bassbox 5.1 simulator.

You may wish to provide / collect more facts and this would be appreciated before deciding what course of action you will take.

Please note we cannot be responsible for incorrect advice where you have not provided complete or accurate information.

All the factors, room placement, tuning and associated equipment will effect the bass performance. But it should not sound crap in any instance.

From you picture the box appears near a wall/ floor juntion in a corner.
Please note the corner location is not the most ideal for the bass to sound best.

Please continue to provide more details.

Ian

[Mike Caldwell]

Hello
Have you checked to be sure that the 18's are in phase. The simple battery test work, use just a 1 1/2 volt battery.
Sorry if this has already been tried or suggested.

Mike Caldwell

[boputnam]

Have you checked to be sure that the 18's are in phase. The simple battery test work, use just a 1 1/2 volt battery.
:idea:

jbl 2245 H thread

Hello I just bought a jbl 2245 H woofer from vintage tube amp or uncle spot speaker repair. the problem I am having is the woofer look the same as the other one but the color is gray kind of orange -redish .the surround is not foam its the same surround thats on the 4312 woofer. what about the low end responce will this effect any thing:blink:

:hmm:

[JuniorJBL]

This may not be applicable but I once had a 2245 that looked like it had a 2241 cone (but with foam surround). It never did sound as good as the original 2245 that I have. The new re cone came from OCS. I decided to just sell it and would work on finding a different one. It would never play quite as low as my original and would pop all the time. I also tried to run a 30hz signal at about 10 watts for 30 hrs but that changed nothing.

[boputnam]

from "D+S Sound Labs" (http://www.dssoundlabs.com/)

[boputnam]

gene's crossover...

I think I see one crossover point worth reconsidering:

In the 4345, the 2245H is taken-up to 290Hz.

Asking the 2202H to go down so low (80Hz) - inside what should be a fairly small subenclosure - might be a great deal of the reason for a lack of bass response. You certainly would not get anything like the magnificent response the 2245H is capable of. :no:

Here's the passive crossover points, and slopes, from the 4345 brochure (L) and 4355 (R, which uses the 2202H)...

[gene]

I believe on jbl speakers terminals red is neg and black is pos. . good question but the drivers are hook up right speakers ports are 4 inch in dia and 5-5/6 in lenth the speaker has two ports per cab. 1-1/2 of fiberglass is use for insulation.. something call biscuit is use for bracing in each corner of the speaker. one speaker is in a corner box on the floor the other speaker is located right befor the patio glass door which that speaker is in the middle of the basement so there 10 ft to the left of the speaker which is a open area. i look in side my jbl L250 my cabs has more brace then the jbl L 250 IF that means any thing

[boputnam]

..ports are 4 inch in dia and 5-5/6 in lenthShould that be 5-5/16 in?

[gene]

I ask dan at dssound to leave me a message becuse I wanted from the start the xovers points to be 80hz 1200 and 5000. but after he did his thing he told me he had to bring up the low end xover point up to ethier 250hz or 290. so I waiting on his responce. but 1200 and 5000 is correct...... for those who wondering why I wanted 80hz.I got my info from gold sound kit 14 but they use a 2206 or 2226h for there midbass . so I knoe he change the crossovers points to 250 or 290hz

[Robh3606]

Are those values correct?? You have a 2mH on the 2245??? Ist order no cap and a first order bandpass on the midrange?? What is the phase on the midrange vs. the 2245?? You have the phase reversed??

That 2202 is sealed??? It's not ever going to get to 80Hz. Not sure what the crossover point is but its not 80Hz. Here is what the driver look like with the 2245 in 10cubic ft and the 2202 sealed in 1 cu ft with the crossover components added as listed.

Rob:)

[gene]

did every body take a vacation. the only person is boputnam whos feeding me input for right now. I am like a kid waking up for christmas waiting on your responce so I can finally get this issue squared away and JAMMMMMMMMMMMMMM

[boputnam]

Patience, man... This information has been a long time coming - and right now you are living with timezones differences, dinner hour, and fine wine time :D .

Get some more info on the internal cabinet detail. Specifically, what the bracing is like and the dimensions of the 2202H subenclosure. email me more pics... :applaud:

gene - if you can, lay the cabinet on it's back and remove the 2245H and the 2202H. Take best possible pictures inside the 2245H opening.

Take best possible measurements inside the 2202H subenclosure.

This is critical info, pard'...

[Zilch]

Did every body take a vacation?I am not asleep. I'm waiting for your response to post #30, 31, and 39.

I've spun out twice here so far; we need some TRACTION!

Also, we're all over the place regarding the size of these boxes, somewhere between 10 and 14 cuft., apparently. :p

What makes you think they're 12 cuft.? That's not what the dimensions you've provided calculate out to.

[The pic indeed scales to ~29" wide....]

[Mr. Widget]

...we're all over the place...Yep... kinda makes me loose interest.

...about the volume...

Based on the answers to the game of twenty questions, I'd bet it's in the neighborhood of 10 cu ft and not any larger than 12 cu ft... the gross internal volume is 14.6 cu ft before you subtract the dog house, any bracing, and the drivers.


Send up a balloon when you've figured it out.


Widget

[Robh3606]

Don't worry so much about the box. Take a look at what the network is doing.

Rob:)

[Mr. Widget]

Don't worry so much about the box. Take a look at what the network is doing.The networks seem to be designed with the same level of care and understanding as the entire system.:(

That is unfortunate... there are some good drivers there. Maybe with a bit of help he can get this thing fixed.:bouncy:


Widget

[gene]

To mr wigget and Zilch- post 38 and 40 should answer your question. Hey guys I had one class of tv/ vcr repair when I was in high school .All of my info from cabinet cubic ft size -ports- xovers etc. I got my info from people I bought this stuff from. I am not trying to bash these guys. my best friend brother turned me on to jbl in 1979. what I do know I love the sound of jbl. q-max vas etc, I dont know a damm thing about any of this stuff. All I know I put my faith in the people I bought my speakers -cabs -xovers-ports from .they gave me my cubic ft size. my port size etc. Now I am trying to get it right. I love jbl sound so much I put my self out there when I had my custom speakers built.crossover points 250 hz - 1200- 5000. cab size 54 high- 29 wide- 19 deep. two ports per cab 4 inch dia and 5 -5/6inch in lenth that is what in my cabs. I know on the croosovers schematic it reads 2245 and the 2202 is crossover at 80 hz But its not, he told me the 2202 would not work so the crossover point is 250hz-1200-5000

[gene]

In the washington dc area only 1 company name speaker factory does it all but his price is high as hell. he wnts about 3000 to 4000 to build the cabs- 1000 to build xovers -100 to test the 2245 qmax vas and etc,I paid 1800 to have my cabs build.... its to late what is done is done:banghead: I hope this problem can be fix :banghead:

[Mr. Widget]

In the washington dc area only 1 company name speaker factory does it all but his price is high as hell.Typically you get what you pay for.

I have no idea where you found a ruler that measures in increments of 1/6th (0.1667) of an inch but whatever...

80Hz, 250Hz? Based on the values posted on the schematic the 1st order crossover between the 2202H and the 2245 is more like 650Hz...

I have no idea what you have here. I am sorry that it hasn't worked out.

Good Luck.


Widget

[boputnam]

...I know on the croosovers schematic it reads 2245 and the 2202 is crossover at 80 hz But its not, he told me the 2202 would not work so the crossover point is 250hz-1200-5000Ignore what you think you know (and don't know...), and let's collect DATA. :applaud:

Can you measure the subenclosure? Remove the 2202H and take L-W-H of that box.

Also, is the crossover anywhere you can take a picture of it? The schematic is clear - but can you talk/email Bill Daniels and get him to email you (or post here hisself... :yes: ) some discussion on the network design. Answer Rob's questions...

[boputnam]

Based on the values posted on the schematic the 1st order crossover between the 2202H and the 2245 is more like 650Hz...I get 637Hz. :yes: But, anyway...

[Zilch]

Gene, we're all here to help you work this out. We just need to be certain of the parameters we are working with.

Please stick your tape measure in those ports and measure the actual depth from the front of the baffle to confirm, like you did with the diameter. Several of us are suspecting that 5-5/6" is not what they actually are....

[boputnam]

Gene, we're all here to help you work this out. We just need to be certain of the parameters we are working with.Bingo.

gene...

Don't get frustrated (yet...). Take some Patience Pills and work on this. You can't go away for 24-hrs and expect things are fixed.

So, by the numbers? Start from the beginning...

1. Measure the ports: Take a tape, stick it in, and measure them. Take another picture of the face of the speaker, too, showing the ports. If you can, have someone take a picture of the measuring tape at the port.

2. Measure the cabinets: L, W, H. Then, tell us how thick the walls are (3/4?).

3. Measure the subenclosure: Lay the cabinet on its back and remove the 2202H. Put your tape inside the opening and best you can, measure the dimensions of that doghouse. L, W, H.

4. More pics of the cabinet interior: Remove the 2245H and try and get some pics of the interior bracing, etc. More, the better...

5. Crossover: We have to believe the crossover topology you provided - so, the hand-off from the 245H to the 2202H is ~637Hz. This is not ideal. This will take some work, too, but IT CAN BE FIXED.

So, relax, collect some measurements and let the gang help. You have some fantastic potential in that cabinet. The guys will make them work for you, but you must focus on giving data.

[Robh3606]

Crossover point is more like 350Hz-400Hz assuming the plots are correct.

Rob:)

[gene]

Boputnam I cant believe what i just measured, my ports lenth. both 6 1/2 inch long. I will take pictures sat of the inside of the cabs and xover- and the 2202 housing I will measure the housing.http://www.audioheritage.org/vbulletin/images/icons/icon8.gif

[JuniorJBL]

Bingo.

gene...

Don't get frustrated (yet...). Take some Patience Pills and work on this. You can't go away for 24-hrs and expect things are fixed.

So, by the numbers? Start from the beginning...

1. Measure the ports: Take a tape, stick it in, and measure them. Take another picture of the face of the speaker, too, showing the ports. If you can, have someone take a picture of the measuring tape at the port.

2. Measure the cabinets: L, W, H. Then, tell us how thick the walls are (3/4?).

3. Measure the subenclosure: Lay the cabinet on its back and remove the 2202H. Put your tape inside the opening and best you can, measure the dimensions of that doghouse. L, W, H.

4. More pics of the cabinet interior: Remove the 2245H and try and get some pics of the interior bracing, etc. More, the better...

5. Crossover: We have to believe the crossover topology you provided - so, the hand-off from the 245H to the 2202H is ~637Hz. This is not ideal. This will take some work, too, but IT CAN BE FIXED.

So, relax, collect some measurements and let the gang help. You have some fantastic potential in that cabinet. The guys will make them work for you, but you must focus on giving data.

Thanks Bo for "LISTING OUT" what needs to be done. Hopefully Gene can continue to reference this post until everyone can be on the same page. This really could be an awesome speaker!!;)

BTW Gene you can post pics of your speakers and what-not by using the "manage attachments" button below the "New Post" window.
I have attached a pic of where the "button" is to do this.
Then you just browse for your pic after you have downloaded them from your camera.

[boputnam]

Crossover point is more like 350Hz-400Hz assuming the plots are correct.Yea, I thought that too looking at your first plot. I interated into the figure until the required inductor was ~2mH. I was intrigued it was close to Widget's. Anyway, I don't do these sorts of things often enough to defend that result (and never before iterated to a given result!).

Let's get some more info...

[Mr. Widget]

My figure was an off the top of my head and not meant as a guide for speaker designing...:D just pointing out that it sure as hell wasn't 80Hz... beyond that a single pole crossover down there will really muddy up the sound. The 2245 will be pouring sound all over the top of the 2202.


Widget

[Zilch]

Here's what I put into BB6P:

2245H driver, front mounted
Box exterior dimensions: 54 x 29 x 19"
Wall thickness, front & side: 0.75"
Damping: Typical
Subenclosure: 14 x 14 x 8" = 0.907 cuft.
Bracing: Unknown, but volume assumed inconsequential
HF driver: 6" dia. x 5" dp., including minimal horn throat volume = 0.082 cuft.
Two round ports, 4" dia. x 6.5" dp.

BB6P calculates:

2245H and port displacement = 0.291 cuft.
Gross internal volume = 14.62 cuft.
Net internal volume = 13.34 cuft.
Tuning = 21.28 Hz
F3 = 43.28 Hz

Gene's box according to BB6P, then, the black curve below.


I asked BB6P for its suggested tuning for that box and driver complement.

Answer: 21.28 Hz; that'd be 6.485" long ports. :)


I then asked what size box and "extended bass" tuning it suggests, as the issue was raised whether so large a box and so low a tuning was appropriate.

Answer: Even larger, and a little bit lower. 15.54 cuft. gross, 14.26 cuft. net, tuned to 20.76 Hz, the orchid curve.


Group delays, bottom.


So, at least insofar as BB6P analysis is concerned, and barring additional disclosures, Gene's boxes are well and appropriately designed. Usable LF response (-10 dB) is 19.24 Hz. Should be plenty nice low bass coming from those 2245H's....

{{Passes baton to crossover team.... ;) }}

[Mr. Widget]

So, at least insofar as BB6P analysis is concerned, and barring additional disclosures, Gene's boxes are well and appropriately designed. :)I think that is being generous... I would agree that the volume and tuning seem to be appropriate now that additional info has come forward... however we know nothing of the design... I'd suggest it is still quite in question.:):)


Widget

[Zilch]

I'm just talking about them as bass boxes, of course.

These are 4-ways.

Best I can do to help further is to shut up now.... :p

[gene]

Hey guys. I just walk thur the door. I had to work -ot . I got to work tomarrow as well but I get off at 3pm I will take pictures of every thing tomarrow and post them.Thanks for your help:applaud: :applaud: :applaud: :applaud: :applaud: .

[gene]

Inside measurements of the 2202 housing is 12 1/2 height- 12 1/2 wide and 8 1/2 deep

[Zilch]

Well, that changes the net internal volume of the main cabinets to 13.19 cuft., your present box tuning to 21.37 Hz, and the F3 to 42.14 Hz, as the exterior dimensions of the subenclosure are apparently 14 x 14 x 9.25".

You're still within 0.01 Hz of BB6P's 21.36 Hz recommended tuning for the main cabinets.

Others will likely be able to analyze the appropriateness of the subenclosure for you.

[ ... Not my job, mon.... :D ]

[gene]

I just sent boputnam, 11 pictures of the inside of my cabinet. bracing the top and bottom of the 2202 housing . crossover- not a great picture. ports If you cant make out some thing let me know .I will take some more pictures of my xovers

[gene]

pictures are not that great. took with my cell phone I wii take some better pictures 2nd pictures is the lower bracing below the 2202 housing. 3rd one is the bottom of the 2202 housing . 4th is the same as the 2nd .5th is the bracing on top of the 2202 housing

[gene]

Will take better pictures. 1st is the inside of the 2202 housing. 2nd agin the top bracing on the top of the 2202 housing. 3rd and 4th left and right ports

[boputnam]

I just sent boputnam, 11 pictures of the inside of my cabinet. ...Sorry, guys... Optical fiber to the coast was taken-out by a muslide... :o: We've been out for about 32-hrs. Land phone lines, Internet, 911 (clever, that!! :banghead: ). Surprised they have us going at all.

I see gene posted the pics (cool!), help is on the way...

[gene]

Hey guys. here are some better pictures:) 1st picture left speaker in basement next to tv. to the left of speaker open area ,10 ft from wall. 2nd and 3rd picture xover.4th picture bracing top 2202 housing . 5th -right speaker in corner

[gene]

odd pictuers. 2245h with wrong cone and surround.-jbl L250 bracing

[JuniorJBL]

That looks like an L250 crossover!!

[gene]

aLL OF MY MEASUREMENTS CAME FROM THE COMPANY I PAIDTO HAVE THIS SPEAKER BUILT. 5- 5/6 INCH PORTS ARE NOT SOMETHING I CAME UP WITH. JUST LIKE YOU GO TO THE DOCTOR AND HE OR SHE TELLS YOU . YOU NEED TO HAVE SUCH AND SUCH DONE. I AM NOT A DOC , IF WHAT THEY ARE TELLING ME DONT SOUND CRAZY I AM GOING TO TAKE THERE WORD. THIS IS WHAT THEY DO FOR A LIVING. THE ONLY INPUT I HAD IN MY SPEAKERS ARE THE BRAND NAME JBL AND THE DRIVERS. ITS A SIMPLE BOX DESIGN .SOME TIME WHEN YOU TAKE A PATH OR ROAD YOU NEVER BEEN DOWN BEFOR YOU DONT KNOW WHAT TO LOOK FOR. BUT LIKE ANY THING ELSE IF YOU WANT IT BAD ENOUGH GO FOR IT. SO THATS WHY I MADE A POST TO LANSING HERITAGE I BELIVE THESE GUYS ARE NOT ONLY SMART BUT KNOW WHAT THE HELL THEY ARE TALKING ABOUT. AND I BELIVE THEY PUT AS MUCH INPUT HELPING OTHERS WITH THERE CUSTOM JBL SPEAKER AS THEY WOULD THERE OWN

[Ian Mackenzie]

Would you like a forum member to come over and listen to your system.

I have just the person in mind!:D

It want cost you a cent...maybe a slab of Fosters:cheers:

[gene]

Yes I would like that.:bouncy:

[gene]

Thank you don mascali very much for your help and your time to drive to my house - gas is not cheap. and hook up your eq, and give me your input and knolwledge. Its a big start in the right direction. :applaud: :applaud: :applaud: thank you gene

[boputnam]

Hey, now that's pretty cool!! :applaud:

So, Don - what did you find?

[Robh3606]

Oh Good

Glad to hear someone made it over there with some gear.

Rob:)

[Zilch]

So, Don - what did you find?Yeah, Don.

We NEED to know!!! :bouncy:

[gene]

I spoke to don last night, he told me he was going to respond to your question. what he told me, the cabinet maker did a damm good job he knew what he was doing. I guess we will have to wait on don to tell us what he found

[gene]

I guess don is busy. what he found the 2202h housing is .8 cubic ft, inside measurements of the cab, take the midrange housing and bracing 12 -1/2 cubic ft. he brought his own music to compare the sound of my system to his. he had the bass and treble set at the half way mark. 12 oclock there was plenty of bass. he use some kind of spectuim analiyzer with a micphone ,my 2425h was a little high compare to the rest of the drivers at the same db level. he said who ever built my cabs knew what the hell there were doing.the cab is tune kind of low . jbl speakers are tuned around 30hz , maybe I should have the my speaker tuned around 30hz and biamp my speakers. he also said the bracing insde the cabs were well done

[Ian Mackenzie]

Gene,

None of this is an exact science.

The tuning of your boxes is based on a simulated model using certain assumtpions. As such the current tuning is only accurate for those assumptions which may or may not be the case in reality.

Ideally, a box can be tuned (within realms of a proper alignment, not a misalignment) for a particular room situation / roomboundary/box location.

Ultimately only you can decide what is satisfactory.

Ian

[Don Mascali]

Sorry for the delay, real life has been a PIA. I will go into detail a little later.

[gene]

hello Ian. I want to change my tunning on my speakers. music bass playback or record on cd is about 30 to 60 hz. I have bass when I play my music.but when I play my dvds the walls-ceiling is rockin. there is a difference in sound quailty. I want the same repsonce out of my music as I do when I play my dvds I also want to biamp my speakers.Don was a lot of help. when I spend that much money on a set of speakers that I know can kick ass I wont stop until I have them right. If I have to wait until I have the money or beg please barrow etc.I will get them square away. don is a big help I cant thank him enough. in this crazy world we live in- don didnt know me from apples to oranges plus gas is high and time is money. thanks agin don if there any thing I can do for you let me know -you wont have to ask me twice. LONG LIVE JBL

[Don Mascali]

Box construction;
54” x 29” x 19” outside, so 14.62 ft3 internal volume, minus 0.8 cu ft for the 2206H dog house, (0.53 ft3 internal). The construction was good of birch veneer cabinet grade plywood and reasonably braced. I would make the net volume at 13.5 ft3

Box tuning;
I wasn’t able to determine the box tuning frequency with a signal generator and cone motion. I had a WT2 with me but there wasn’t a computer in the room that we could use. Gene has to have one of his 2245Hs reconed, so I will bring a laptop back to test them both up when He gets it done. My best guess is that the box is tuned a bit low with a gentle roll off and is good candidate for a bump filter. Gene is still climbing the learning curve and this might be a problem for him at this time, as would a bi-amp set up. For all but a few of us hardcore knob tweekers, it can cause more trouble than benefits. He has some nice old high end Technics gear with a dual 31 band EQ and an analyzer. It also has some nice bass shaping controls on the pre-amp and he has a Stasis amp that seems to be up to the job but certainly could use some help.
We did some education on the nature of the “Bass” he was looking for (Thanks to Carlos Santana’s “Supernatral” percussion). We think that a higher tuning would be appropriate at this time and drop it down when he catches up on equipment and expertice.

Room;
We set up the Behringer 61 band RTA and test mike and looked at some pink noise. The room is short on the speaker to listener distance and wide with no wall on the left side. The left was the only speaker we tested so there was very little help from room gain. The speaker was up to the task when we gave it some thump to work on. And played with the controls. We found a severe 40 hz null in the room center and it is at about 45 hz at the preferred listening position (About 6-8 feet, so it’s almost nearfield conditions) We also found some reinforcement at about 100 to 150hz that made the 2206H LMF sound a little too hot and therefore the whole system sounded “bass shy” in comparison. With no L-pads on the speakers we may have to dial it in with the EQ later.

I enjoyed meeting with Gene and found we work in the same industry. He’s a nice guy, and was frustrated that I don’t drink, so that he could make me feel more at home.
We have some work to do but I think he’s got a great set of speakers to play with and it is up to us to understand the fine points of care and feeding them.

More shall be revealed.

Here is Gene, He's a big guy.

[Zilch]

Here is Gene, He's a big guy.Yeah, well, his speakers are pretty big, too! :p

VERY nice, Gene.... :thmbsup:

Thank you, Don, for helping with Gene's system. :yes:

[boputnam]

We have some work to do but I think he’s got a great set of speakers to play with and it is up to us to understand the fine points of care and feeding them.

More shall be revealed.

Great effort, Don. Interesting the null(s) you found in the room.

Gene standing next to those speakers makes them look like small near-field monitors!

[Ian Mackenzie]

Don and Gene,

Very nice post and picture.

Gene, I think it would be wise to wait until you have reconed your other woofer before considering updating the tuning.

Until then enjoy.

Ian

p.s My in box is full and will be closed until I work out what to do with all those pms.

[johnaec]

p.s My in box is full and will be closed until I work out what to do with all those pms.You do know that you can download PM messages, (function at bottom of PM page), then delete them from your PM's.

John

[Ian Mackenzie]

Well I think it is great someone from The Lansing Forums managed to see you Gene.

All this takes time. Sometimes its the journey that counts.

But with JBL's the results are really worth it.

Ian

[Ian Mackenzie]

Hey Gene,

Can you give us a current tally of your amps and other stuff driving the speakers. I know you have talked about amps in other threads so it would be nice to consolidation what you have in one thread.

Another picture would be nice!

Ian

[Don Mascali]

Ian,

Here is a cropped image of the gear on his TV that drives the speakers now. You can see the curve on the upper EQ that I put in to counteract the room modes. When all is in place we can take the proper action.

Gene,

Get moving on that recone. I'm anxious to see how all of this will play out.:D

[gene]

Ian,

Here is a cropped image of the gear on his TV that drives the speakers now. You can see the curve on the upper EQ that I put in to counteract the room modes. When all is in place we can take the proper action.

Gene,

Get moving on that recone. I'm anxious to see how all of this will play out.:D I drop the woofer off yesterday to be recone:bouncy:

[Ian Mackenzie]

Nice collection of gear..is that a Threshold or a Naka with Stasis?

Ian

[gene]

Nice collection of gear..is that a Threshold or a Naka with Stasis?

Ian gene [quote] nak pa-7 stasis

[Robh3606]

Hello Gene

What's the Technics????? Is that a preamp?? I have an Su-A6 and love it.

Rob:)

[gene]

Hello Gene

What's the Technics????? Is that a preamp?? I have an Su-A6 and love it.

Rob:) Hey rob [quote]gene sua4

[gene]

Hello I just got my woofer back from being recone:bouncy:

[doucanoe]

Im glad to hear that you are on well on your way to getting your speakers straightened out Gene.

This is a little off topic, but I was something in one of your photos you provided that bothered me some.

Maybe besides the room issues and what not, I think I see another problem. Thats a strange image on the port tube wouldn't you agree. I think that you have a ghost in the machine as it were.:D