Jump to content
The Klipsch Audio Community
Sign in to follow this  
Wim M

DIY Bass cab - KP 480 style

Recommended Posts

Currently we are running a pair of La Scala IIs combined with a pair of Tuba HTLPs (big thanks goes to @jason str)  The LSIIs are bi-amped, time aligned and EQed flat (with the enormous appreciated help of @Chris A)

 

Two years ago I did a DIY project with a pair of 18 "JBL 2242 drivers (specs) which didn't work out very well.  The major problem was that I didn't realize the JBLs are bass drivers, and actually not usable for sub applications in a bass reflex cab, where they have problems to keep up with the high efficiency of Klipsch speakers.  Also, at that time, I didn't have the proper DSP and amplification.  Now I have a Xilica XP 4080, with 2 unused outputs, and a spare QSC DCA series amp.  The JBL 2242s are on a shelf in our basement in their original packaging, and I want to put them to use.

 

Klipsch made the KP 480 a number of years ago, a bass cab loaded with an active 18" and a passive 15".  They were to go with the industrial La Scalas.

 

So I came with the idea of building a pair of bass cabs in the style of the KP 480, each loaded with a JBL 2242 and a Dayton Audio 18" passive radiator (specs)   The bass cabs should have the same footprint as our LSIIs, so the bass cabs can be put under each LSII.  Height should be minimum so that the top cab of the LSII is not raised too high.  This will give a net internal volume of  around 5,8 cu ft.  The PR can fire backwards into a corner.  I will let the bass cab handle the 40 - 120 Hz region,  below 40 Hz can be done with our Tubas.

 

Great idea or a definite no go?  Thanks in advance for sharing your thoughts with me!

 

 

PICT0198.thumb.JPG.894f26522ab00b591609614d20356ecd.JPG

  • Like 1

Share this post


Link to post
Share on other sites

If these are to be used with the LS II and Tubas the answer is no.

 

 

 

 

Share this post


Link to post
Share on other sites
53 minutes ago, jason str said:

If these are to be used with the LS II and Tubas the answer is no.

 

 

 

 

 

Is it because I'm going to put a direct radiator in between two horns?

Share this post


Link to post
Share on other sites

Simply no reason for it.

 

What i would suggest is building a set of angled risers and raising the crossover point.

 

 

 

Share this post


Link to post
Share on other sites
14 minutes ago, jason str said:

Simply no reason for it.

 

You 're probably right.  It just sounded fun building those extra bass cabs, the only thing I'm missing right now are the passive radiators.

 

In our region you can often hear those JBL drivers in PA applications, and I really love the sound of those 18s, that's why I bought them in the first place.

22 minutes ago, jason str said:

 

What i would suggest is building a set of angled risers and raising the crossover point.

Could you expand this a bit please?

Share this post


Link to post
Share on other sites
10 minutes ago, Wim M said:

 

Could you expand this a bit please?

 

The crossover or the risers ?

Share this post


Link to post
Share on other sites
31 minutes ago, jason str said:

 

The crossover or the risers ?

 

Both please

 

Share this post


Link to post
Share on other sites

Simply raise the crossover point using whatever device you are using, use REW or whatever software to confirm you have the right settings. My La Scala's are high passed @ 200 Hz & THTLP low passed @ 45 Hz, crossover is near 95 Hz just for reference.

 

For the riser just use scrap wood, books or whatever you have handy to mock up for testing, sit wherever you normally sit and get the squawker high enough so its facing your ear by simply squating a bit to be sure you can see the driver at the back of the lens, now you will have basic measurements measure for the new risers.

Share this post


Link to post
Share on other sites
13 hours ago, jason str said:

Simply raise the crossover point using whatever device you are using, use REW or whatever software to confirm you have the right settings. My La Scala's are high passed @ 200 Hz & THTLP low passed @ 45 Hz, crossover is near 95 Hz just for reference.

 

Jason, I think I'm not completely getting this.  If you high pass your La Scalas at 200, and lowpass your THTLP at 45, what do you use in the 45-200Hz range?

Share this post


Link to post
Share on other sites
37 minutes ago, Wim M said:

 

Jason, I think I'm not completely getting this.  If you high pass your La Scalas at 200, and lowpass your THTLP at 45, what do you use in the 45-200Hz range?

Probably the sound that makes it past the filters which aren't brick walls.

Share this post


Link to post
Share on other sites
19 hours ago, CECAA850 said:

Probably the sound that makes it past the filters which aren't brick walls.

 

If I'm not mistaken, I believe he said he uses 48 dB slopes.  

Share this post


Link to post
Share on other sites
4 hours ago, Wim M said:

 

If I'm not mistaken, I believe he said he uses 48 dB slopes.  

Correct but we're talking about 2 octaves.  Maybe he'll explain.

Share this post


Link to post
Share on other sites
On 2/10/2018 at 2:56 AM, Wim M said:

 

If I'm not mistaken, I believe he said he uses 48 dB slopes.  

 

I don't use steep slope filters like that with my La Scala & THTLP system, i just mentioned it to another forum member for his setup as he uses different mains with a lower crossover point.

 

 

 

 

 

  • Like 1

Share this post


Link to post
Share on other sites

.....and it worked perfect.

Sent from my SM-G950U using Tapatalk

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...