You don't lack bass, you have too much treble

...and I'll vote with @jkf011 , ultimately.  Too much I relate to the 'basser's that cruise about, megawatt subs up to anything loose in the ride rattling...

Great for one's GI tract, I'd guess...not my problem, tho'...🤷‍♂️

Dial them in to what seems to fit the mix and/or program.  I can dish out plenty, but know when it's 'quite enough, thenkewu....'

Been around enough garage bands, gone to enough concerts, rattled enough glassware...😏

@mahgister 20hz in your 'phones?  

Take care there, Rock'nRoller.... ;)

Better off making self a tactile bass shaker suit.....

"See the man vibin' down the street....'citing all the windows he meets...

Mahg's the Bassman....vibin' all the fans..."

(Appropo....playlist just brought up N. Youngs' Rockin' in the Free World....*L*)

my K340 is an hybrid with two dedicated cells and with an internal grid of 5 Helmholtz tuned resonators separating perfectly among other effects bass and mids and making this phone to give deep bass without flowing interaction with usual bass..

Not only that but i modified and optimized them with 6 mods... The main one is i put inside and outside anti resonance materials and dampers of two kind to comnplement each others ...

By bone resonances i feel deep bass with my chest and feet...

is it 20 hertz ?

i did not measure it but i listen big church organ music of Bach and some organ go down 8 hertz...

I am pretty sure i hear then 20 hertz or near it with my feet ...

I disliked all headphones i bough... Save the K340 i like a lot after 6 months of intensive studies about it even with the original paper of the founder of AKG who design it...

I spoke with Kennerton representant about hybrid headphones as the K340... Because i asked them how they will build one...

They said it is too costly to design right because of the research implkied, too costly to make and too litlle profit...

This design complexities is the reason it takes me time to improve them so much that they are my audiophile reference now not my small modified speakers so much i love them ..

 By the way if the recording make it possible  i hear the soundfield out of my head...Not inside my head...

 My best to you my friend ...

@mahgister 20hz in your ’phones?

@mijostyn very good points.  I have bass traps in the corners behind my speakers, they actually help greatly with the room. I've listened with and without them and the really help

I also use a Krell KBX electronic balanced crossover designed specifically for my speakers (incorporates some wave shaping circuitry) with low and high adjustments that I use to tune slightly. Trying to get the flat response first and then adjust slightly for effect.

I am sure that I can do more.  Room treatment is hit or miss with no refunds if you miss and most are seriously ugly.  But, sometimes worth a try.

I know McIntosh labs actually have a equalizer that might help that has balanced in and outputs.  I am looking into that or some other.

But, I'm pretty much "there" with my system otherwise. I just replaced the panels on my Martin Logan Monolith III speakers and upgraded the woofers to the Pearless woofers.  Nice!

Those speakers are still outstanding and with the Krell crossover, I don't hear any gaps or timing issues between the panels and the woofers.

I'm sure subwoofers may help, but I don't feel I'm missing anything. Especially when I go to my dealer friends and listen to my music on their equipment with subwoofers.  

But, one never knows whats in the future.  I've tried subwoofers added before, and couldn't dial them in correctly to the extent they weren't hurting the sound more.

But I know there are some really nice subwoofer systems out there.

Also, My Audio Research REF 10 pre-amp is simply outstanding an well no, not changing that anytime soon.

Thanks for the suggestions,

enjoy

Another side of the same coin:  If your system is well-balanced and you add subwoofers thereby extending the response an octave or more on the low end, the net result may no longer sound balanced.  In this case, it can make sense to flex your DIY muscles a bit and add a rear-firing tweeter whose response is tailored to filling in the top octave where your main tweeter is beaming. 

In my opinion.

Duke

@audiokinesis My favorite all time speakers, the Snell A/IIIs used that trick, also contributed significantly to imaging.