JBL 4367 = Sleep Denervation

@james633 

I forgot to mention. if you high pass the JBLs to subwoofers at 80 to 100 Hz block those ports off on the JBLs. You no longer need them to enhance low bass and they are leaking muffled midrange. The low frequencies they enhance are being taken on by the subwoofers. Stuffing them with socks is not the right way to do this. You do want to pack them with Polyfil (Parts Express) then cover them with something attractive like 1/2" thick walnut cut to shape around the woofer so it reaches the four lower grill cloth sockets.. You can finish it with clear acrylic lacquer in a spray can sanding between coats with 320 grit sandpaper. It will require at least three wet coats. You can get the male pins to fit those sockets at Parts Express or you can remove them from the grills. You want to make sure there is some polyfil between the walnut and speaker around the ports. This is totally reversible should you ever want to sell the speakers. 

I can't stress enough the power of digital signal processing when it comes to integrating subwoofers and tailoring the sound of your system. The MiniDSP SHD preamp does everything you need at the extremely reasonable price of $1300.         I just set one up in my son in laws system and am very impressed. I you are computer literate you will enjoy this immensely and enter a whole new world of high fidelity. Plus your system will kick ass. 

mijostyn...can the MiniDSP SHD work with subwoofers only ? I don`t want

my turntable setup run through anything digital.

Mijostyn,

I have looked at the miniDSP SHD. It is much cheaper than other options. Do you feel there is any resolution loss with it? Think the output stage is good enough? It complicates my home theater pass through as I would have to use the analog input. 
 

I am currently highpassing at 60hz. 24db slope on both sides. 

@james633 - 

As mentioned in a different thread, I’m using the 2269H drivers that we know are used in the SUB18 cabinets.  They are musical and very enjoyable; not just air moving pro audio speakers.  My cabinets mimic the SUB18 cabinet volume.

@mijostyn writes:

“Adding subwoofers to a system is not only to add more low end, it is also to lower distortion in the main speaker. With these speakers a minimum of two 12" subs is required and you have to use a high pass filter on the main amplifier, a full two way crossover. Digital is best. Crossover at 80 Hz. Do this and you will take your system a large step forward.”  - I fully agree with these statements!

I am using McIntosh’s MEN220 for my subwoofer crossover and also use the room correction software to remove a node in my room.  It’s a nice unit.  Marchand makes great analog crossovers for reasonable prices.  The JL Audio CR-1 is very nice and the SPL crossover looks to be exceptional as well.

I also feel there is “no replacement for displacement” and while spousal approval is low for such a concept in living spaces, if you really want a system to “hit”, decent cabinet volumes are helpful.  This may be one of the reasons (of many) you are experiencing exciting audio with the addition of the 4367’s.  I experienced a large upgrade in low frequency response when I ditched the JBL ASB7118 cabinets in favor of the custom cabinets I had built by Joe at Stewart Speaker Systems.  The stock ‘7118 cabinets were too small and tuned for a “rock box” type sound.  The far larger cabinets that mimic the dimensions of the SUB18 are just right.  Flat response and musical in sound.

Adding JBL paper cone 18” subs with the accordion surrounds would be great synergy with your 4367’s that use identical woofer construction.  I’m a firm believer in synergy between all drivers in a system and maybe that could be some of the dissatisfaction with the JL Audio subs you are experiencing.

All JBL drivers in the sizes of 18” to 15” to Horn just seems right to me and I think you’d really have sleep deprivation if you added nice subs, an appropriate outboard crossover and power amp to your system in your nice room.  That would be a, pardon my French, effing unbelievable experience even over what you are enjoying now.

Thanks for letting me ramble!  What a fun journey!

It's funny in this thread I just saw and commented on the systems of @jheppe815 @ditusa and @james633 well done gentlemen one and all. 😎