La Scala Variant

[Dave A]

In the same vein of thought as the Super MWM and using as much of a 60" x 60" sheet of Baltic Birch as possible here is a thought on making a La Scala as big as possible withing those limits. The height of the dog house is as normal. The plenum behind the woofer is deeper and the doghouse is set back from the front edge for more protection from dings. I figure the bigger plenum, the longer travel and wider mouth should all help bass out and since you are cutting up this much material anyway why not make it go as far as possible.

  Debating the separate horn bin and thinking seriously about making it large enough for the bigger MAHL tweeter which I prefer if I have a choice. I will use the standard K400 horn with the K-55-v driver. I figure to use an AA crossover for this with the Zeners pulled out of the circuit.

[ClaudeJ1]

Another winter project.

[Dave A]

Yes and looking into cabinet saws to do these with. Oh and this is using 1" Baltic Birch, the superior cabinet material ;D

[ClaudeJ1]

On 11/13/2018 at 10:27 PM, Dave A said:

Yes and looking into cabinet saws to do these with. Oh and this is using 1" Baltic Birch, the superior cabinet material ;D

Is this after the Super MWM build???

[Dave A]

Of course it is Claude, there are priorities after all and thunderous clean bass is at the top of the list.

[moray james]

this is not much different from a Peavey FH1 and it is not going to get you very much lower (a few Hz only) than a LaScala. If you want bass extension look to a either a University or a Beck California.

fh1_002.pdf

[Dave A]

Hi Moray,

  I figured it would go deeper but not by a whole bunch of hz. Something to do with parts I find I have on hand once again and it is an excuse to make a top section for using my larger MAHL tweeter which will make a big difference. Add the two together and it becomes a worthwhile project.

  I have those plans and many others but like how bass sounds from MWM's and want more there since I have the space to do so. The MCM 1900's are really remarkable and I want the extra bass the supers would bring to this set.

[jason str]

That cabinet is nearly the size of the BFM DR 300 if you were interested in having a look at something different, no folds in the bass bin design like the others and gives you more squawker options if you choose to do so as you are able to cross it over at a much higher frequency

[Marvel]

The DR 300 still doesn't go very low. What is the bass horn geometry on those?

 

Bruce

[jason str]

9 minutes ago, Marvel said:

The DR 300 still doesn't go very low. What is the bass horn geometry on those?

 

Bruce

 

Any short horn is really going to need a good sub to fill in the lows.

 

Its an actual waveguide from driver to mouth.

[JohnA]

On 11/13/2018 at 10:22 PM, Dave A said:

In the same vein of thought as the Super MWM and using as much of a 60" x 60" sheet of Baltic Birch as possible here is a thought on making a La Scala as big as possible withing those limits. The height of the dog house is as normal. The plenum behind the woofer is deeper and the doghouse is set back from the front edge for more protection from dings. I figure the bigger plenum, the longer travel and wider mouth should all help bass out and since you are cutting up this much material anyway why not make it go as far as possible.

  Debating the separate horn bin and thinking seriously about making it large enough for the bigger MAHL tweeter which I prefer if I have a choice. I will use the standard K400 horn with the K-55-v driver. I figure to use an AA crossover for this with the Zeners pulled out of the circuit.

 

 

Good Start!  But, don't increase the volume of the doghouse, it controls the woofer's resonance.  Keep the horn throat and initial expansion, behind the doghouse, the same, too.  Then, increase the total area of the bass horn exponentially and make the bass horn longer and the mouth much larger.  That'll get ya woofin'!  maybe make the doghouse a triangle like an FH-1, should be easier to build, too.  

[Dave A]

1 hour ago, jason str said:

That cabinet is nearly the size of the BFM DR 300 if you were interested in having a look at something different, no folds in the bass bin design like the others and gives you more squawker options if you choose to do so as you are able to cross it over at a much higher frequency

I like the La Scala bass bin for punch and want to try it in conjunction with my larger MAHL tweeter. The lower hz no matter what it is will be welcome. This is an experiment for something I may decide to start building later.

[Dave A]

5 minutes ago, JohnA said:

Good Start!  But, don't increase the volume of the doghouse, it controls the woofer's resonance.

Claude found that the deeper plenum behind the woofer on the Super MWM helped lower the bass according to the software. Are you thinking that I should keep the original size behind the woofer and extend an expanding throat like a mini MWM in front of it? It will have an additional foot to travel and a bigger mouth at that point over the OEM cabinet.

[JohnA]

Yes.  The La Scala is a good basic design.  The compromises are the straight sides of the dog house, to get more back chamber air volume, and the short horn length and mouth to keep it compact.

[moray james]

if you look at the data of the Peavey FH1 which is a good bit larger than a LaScala you will see it only plays a little bit lower it is already 3db doen at 58 Hz you would want to cross it at about 90 Hz for decent results. I tried to find the data on a larger and much newer Caire design which as I sad is larger again than the FH1 and it does not go lower than by a few Hz. You really have to add some length and mouth size and the package will grow a lot in doing so.

   Re the dog house size I concur do not make it larger if anything smaller will help.

Just found the Caire info see attachment link.

you might consider DJK's vent mod for a LaScala or FH1 to pick up some bass extension and keep your over cabinet size acceptable,

 

https://community.klipsch.com/applications/core/interface/file/attachment.php?id=105870

 

 

 

 

 

 

 

 

 

[Zilch510]

On 11/14/2018 at 5:22 AM, Dave A said:

In the same vein of thought as the Super MWM and using as much of a 60" x 60" sheet of Baltic Birch as possible here is a thought on making a La Scala as big as possible withing those limits. The height of the dog house is as normal. The plenum behind the woofer is deeper and the doghouse is set back from the front edge for more protection from dings. I figure the bigger plenum, the longer travel and wider mouth should all help bass out and since you are cutting up this much material anyway why not make it go as far as possible.

  Debating the separate horn bin and thinking seriously about making it large enough for the bigger MAHL tweeter which I prefer if I have a choice. I will use the standard K400 horn with the K-55-v driver. I figure to use an AA crossover for this with the Zeners pulled out of the circuit.

 

Just wondering...

Is this design based on the old, or new La Scala's?

[Dave A]

5 hours ago, Zilch510 said:

 

Just wondering...

Is this design based on the old, or new La Scala's?

There is no difference on the internal dimensions as far as I know. This was never built and was based on the basic Ls Scala plans out there everywhere. I would redo this if I were to build it so the pieces would all cut out of a 60" x 60" sheet of Baltic.  One thing I did do is rebuild a set of bass bins and used 25mm Baltic for the sides and 18mm for the rest but made the bass bin 3" deeper to protect the point on the doghouse which is always getting beaten up. It was a nice sounding set.

[karlson3]

That horn would look very nice - did you work out its hornresp model yet ?

 

Re: BFM - although gentle curved folds, one would have to still deal with directivity issues (matching the midhorn)  It still might be a really good folded horn down to 70Hz or so.,  At least BFM builds light. 

 

Beck's Califronia is like a free standing box version of the K-horn

 

Here's one of my FH1 outdoors

 

 

I need to get rid of my FH-1 pair so to have space for my K15's

 

[Dave A]

19 minutes ago, karlson3 said:

That horn would look very nice - did you work out its hornresp model yet ?

 

Re: BFM - although gentle curved folds, one would have to still deal with directivity issues (matching the midhorn)  It still might be a really good folded horn down to 70Hz or so.,  At least BFM builds light. 

 

Beck's Califronia is like a free standing box version of the K-horn

 

Here's one of my FH1 outdoors

 

 

I need to get rid of my FH-1 pair so to have space for my K15's

 

No I have not since I never expect to build it. I did however post the drawings here for anyone who wants to. I require something much more substantial than a La Scala and ended up with the Super MWM

[karlson3]

It woujld be a pretty proiject for suire.   It made me think of Thuras speaker - That would be sustantial size wise 

 

http://www.itishifi.com/2016/05/loud-speaker-for-auditory-perspective.html