Subwoofer with Lascala / Cornwall's Passive

[JohnA]

I have 4 VMPS Larger Subs (92 dB/w/m) driven by 2 Acurus A-250 amps (300 to 350 wpc) in the corners.  That keeps up with my La Scalas and Heresies nicely, without noticable distortion.  

 

The drivers must be mated to the cabinet volume and tuning.  Don't substitute other drivers in a completed cabinet.  K-33s and K-34s are not great sub drivers.  Choose others that are better at it. 

 

Certainly add power. 

 

Get an SPL meter with a known calibration or software (REW?) to set your sub levels and leave them alone.  Different recording have different bass levels and that is part of making great music. 

[Tom05]

4 hours ago, JohnA said:

I have 4 VMPS Larger Subs (92 dB/w/m) driven by 2 Acurus A-250 amps (300 to 350 wpc) in the corners.  That keeps up with my La Scalas and Heresies nicely, without noticable distortion.  

 

The drivers must be mated to the cabinet volume and tuning.  Don't substitute other drivers in a completed cabinet.  K-33s and K-34s are not great sub drivers.  Choose others that are better at it. 

 

Certainly add power. 

 

Get an SPL meter with a known calibration or software (REW?) to set your sub levels and leave them alone.  Different recording have different bass levels and that is part of making great music. 

Sounds like you’ve got a sweet setup, and BTW ,  good advice .

[Tom05]

As to the benefits of running these fully horn loaded speakers full range, we should  also consider the fact that running full range can increase the number of point sources that contribute to low frequency bass output , and the beneficial effects that this has on balancing room modes . In the case of Klipschorn , we have a very good contribution to 35hz , so if we have one subwoofer source  and two Khorns running full range , and a bit of overlap, we have a three point source down to 35 hz . The result of this is better sounding and more natural bass coverage in your listening room, not to mention more headroom. Below 35hz when the subwoofer substantially takes over, the bass will act more as a single point source from the subwoofer, but it will be working within a very small frequency range , and can be positioned to satisfy the listening position.

[Audible Nectar]

I run two JBL 4638 cabs in my all-Cornwall theater. These have the efficiency and brawn to keep up with these high efficiency speakers. Another is the JBL 4642 (single 18"), then to look at Klipsch they have the KPT-904 and similar. These woofer cabs can run with the big Klipsch Heritage beasts and can do it and not be horn loaded - these are made for pro use. My JBL 4638 pair run effortlessly with my Cornwalls and make "keeping up" with the big Heritage a breeze, and modern pre-pros can adroitly blend these beasts with your existing mains.

 

I am a big proponent of using these types of cabs for LFE on Heritage as they are capable of the job and relatively inexpensive as well (oft can be found used, especially out of "theater rescues"). You don't have to get fancy on power either, biggest issue is QUIET power, in my case a Crown K1 driving the two twin woofered cabs. 

 

On 3/10/2023 at 10:00 PM, mrparisi said:

I'm sure the newer Klipsch subwoofers are good but I had one about 10 years ago and all it did was dance around the floor and vibrate.  It wasn't for me but that was a long time ago. 

 

I really believe these new Klipsch beasts are another animal entirely, that is if powered is OK. They do appear to have the ability to blend the liver, to be sure. Klipsch has really upped their game on subs. I'm a pretty hard bitten passive guy though, and I'll probably die with mine (these cabs do half a century in theaters and they'll do that same 50 years here).

[Bubo]

Buy some inexpensive class D amps

parts express has some

also plate amps for subs

the pre amp controls the volume of the subs

Enjoy your project subs

 

[mrparisi]

On 3/14/2023 at 2:30 PM, JohnA said:

I have 4 VMPS Larger Subs (92 dB/w/m) driven by 2 Acurus A-250 amps (300 to 350 wpc) in the corners.  That keeps up with my La Scalas and Heresies nicely, without noticable distortion.  

 

The drivers must be mated to the cabinet volume and tuning.  Don't substitute other drivers in a completed cabinet.  K-33s and K-34s are not great sub drivers.  Choose others that are better at it. 

 

Certainly add power. 

 

Get an SPL meter with a known calibration or software (REW?) to set your sub levels and leave them alone.  Different recording have different bass levels and that is part of making great music. 

I used bass box to do my calculations. You plug in the specs of the driver and it tells you volume for sealed and vented. I didn't build my subs willy nilly. My only mistake isn't choosing more efficient drivers. The Adcom is working nicely but I may try a d powered amp to see how that works. Many tracks have bloated bass or use bass distortion for effect. Other tracks have thin bass so I like to adjust my bass accordingly.

[JohnA]

21 hours ago, mrparisi said:

I used bass box to do my calculations. You..,...

 

 

 

I use BassBox as well.  Then you know you can't drop in different drivers in to a completed box.  If you find another driver that's more efficient, it won't go as deep, if it works in your box.  It sounds like you have a calibration error or a lack of power, or both.  

 

As to some recordings sounding thin, ..... the artist may have meant it that way.  That's why I don't mess with mine and are particular about the recording.