A question about headphones

I like rich base.  Do open-back designs lack this?  I have heard 'bright' and a lack of base.  Thanks.

My BT transmitter is something cheap off of Amazon.  It fits the 1/4" plug on my preamp through an adaptor.  There must be something better out there?

I have a DAC and a Matrix DCC.  Thanks .

The B&W lineup looks nice but it seems BT only, no combo.  Is this correct?

A couple of things come to mind.  First, I only plan to use these in my music room so why would I want noise-cancelling?  It seems the money spent on that feature could be better served elsewhere.

My preamp has two sets of outputs, RCA 1 / XLR and RCA 2 / XLR.  I have it configured so output 1 is XLR and not RCA so it feeds my power amp.

Output 2 is RCA and I have a 20' dual-RCA cable off of this going to my SVC-2000 Pro sub.  The sub is closer to my listening position.

Could I put some RCA Y-splitters on this cable before it goes to the sub and then add a headphone amplifier?  The amp would be close to where I would listen with headphones.  Thanks.

Thanks for all the feedback and suggestions

UPDATE:

I just wanted to give all of you that took an interest in my project an update.  I purchased a 'new to me' Shitt LYR 2 headphone amp and a pair of Hifiman HE-R9 cans.  To sum it up, I couldn't be happier for a first time setup and came in under $1000 CDN.

The amp and headphones sound fantastic.  There are two tubes in the amp and they have a great sound.  As a bonus, I don't have any of the interconnect hassles I thought I might have.

RCA Output 2 on my preamp ran directly to the line inputs on my SVS SB-2000 Pro sub.  I plugged these directly into the line in on the LYR 2.  Line out on the LYR 2 goes to the sub.  When the headphones are connected, the inputs to the sub disconnect by themselves automatically.

The only manual step I have to do is turn off Output 1 on my preamp that feeds the balanced input to my power amp.

The HE-R9 can kick out a lot of bass that I like with the 60s and 70s music I enjoy.

Prior to all this, I did have a set of Bose BT ANC headphones.  You know what they say, 'no highs, no lows, must be Bose'.  Anyway, there is no comparison.  I was looking for a hi-res audiophile type solution for home and am satisfied with my start.  Knowing me, now I will want to collect headphones and an open-back design will be first on my list.

A lot of your opinions factored into the direction I went so my thanks goes out to your knowledge, experience and willingness to help.

I tried plugging my headphones directly into the 1/4" plug on the front of my C48 preamp and it sounded terrible - at least as far as hi-fi is concerned.  There was no comparison connecting the line out on the preamp to the line in on the headphone amp - the sound was amazing!  

I was mentioning in my earlier post that the only manual task I had to do before listening with the headphones was to turn off output 1 that feeds the power amp.  Well McIntosh makes that too easy because that function is on the McIntosh remote control (which I never use).

I have heard a lot about the Sennheiser HD800s in that the name comes up often.  Depending how much use my present headphones get, at least I  now have a gift suggestion for my wife the next time she asks!

@soix don't forget Donald Rumsfeld:

“There are known knowns — there are things we know we know.  We also know there are known unknowns — that is to say, we know there are some things we do not know. But there are also unknown unknowns, the ones we don’t know we don’t know.” 🤣

Thanks for the tips marco1.  I have two pair of extra tubes that came with the amp, different makes.  I think the previous owner was doing exactly what you suggested.  :-)