Ya either of these are good options. Depends if OP wants to buy used or not. He can probably save a lot if he does. @checks If you’re planning to upgrade later I’d suggest investing in a better AMP/DAC at the start so you don’t need to buy another one later down the line.
Yeah I totally don’t mind if I gotta spend extra and have two less things to worry about upgrading in the future. Would something like a Magnius/Modius be a decent step up if I wanna go a bit better than like a Adam stack or the magni/modi stack?
I think as far as headphones go, I’ll probably end up looking at either LCD-2s or like check out a pair of Argons or T1 3rd gens. There should be some audio shops by me that I can stop by and most likely try a pair out before making a buy.
I’ll probably look at getting a decent budget pair of IEMs though (Moondrop Arias or something) just to dip my toes into IEMs and see what’s up.
Would there be anything from Fostex/Denon worth looking at?
Ya Magnius+Modius is good upgrade, or the EL amp 2+ and EL dac 2+ from JDS Labs if you need more power.
If you are, get Tripowin Olina instead of Aria. Way better. It’s pretty much Tanchjim Oxygen 02 (a $275 IEM that competes at the $500 range) but $100 since it uses the exact same dynamic driver and like 97% of the tuning. So you’re basically getting a $500 range IEM for $100. Heads up neither Aria nor Olina is basshead though; FOCUS EDM ($150 on sale) is value king as a basshead set under $300.
Edit: You might also need to research the amps needed if you are looking at Argons and Fostex since those need a lot of power. I mean I was using my speaker’s amp for my Argons a few years ago 
Maybe their newer models need less power now, but double check just in case 
I switched over to the 8xx with dekoni elite hybrids.
Zmf also just released some pads for the 990 if you want to breath some life into your old phones
Fostex th-x ebony or purple heart would be nice but can only be had used because drop doesn’t have them anymore 
otherwise the fostex th610 should be nearly the same but hasn’t the same nice looking cups, from Denon ah d7200 is nice or if you can find a used ah d7000 for a good price
The magnius Modius stack should have power for days but if i remember correctly the balanced output sounds noticeable better than the single ended
lol looks like this was answered before I got a chance to get to ya.
I would actually mention the same headphones here next to the argon… In the case of denon over there though those have better imaging. However, something like purple heart( I own that one myself) is extremely heavy in the bass and satisfyingly so. You can still find them here and there around the $400-$600 line. There was three variations, mahogany, ebony, and purple heart… purple has the most
Though were swinging to closed backs at this point unfortunately… as mentioned though most open backs just do not compete with closed or iem in terms of base and its qualities… The best one I seen was that T1 or Audeze’s honestly… and even then as @VIVIDICI_111 mentions… the IEMS surpass them in terms of the qualities your searching for… however, if open back over ear is the goal… The ones recommended for open back already are the ones I encourage trying… denons are closed backs as are fostex but they are pretty much the bass head brands next to what… sony? but sonys are kinda junk in most cases
wait what…? why did nobody mention this to me… appreciate that… thats a buy for the perfs. Don’t put leathers on DT 990 it dampens the hell out of them usually makes them worse. Less they worked some weird magic
Now that you mention Sony maybe a Sony MDR z7 mkI could be an open back option ?
thought that was a closed back, am I recalling that wrong or is there an open back variation? That honestly was the one I thought of when I mentioned sony since its very “fun” bassy
I heard good things about the Sony MDR Z7 and Fostex TH610. Just a heads up though since they’ll most likely push you over $1K after amp and dac.
@checks But I mean if you’re willing to invest in a better amp/dac then might as well just invest in a $1500 Fostex TH900 (one of the best basshead sets) and be done with it 
You pretty much have to go to closed-back if you’re looking for basshead headphones. That’s why I suggested IEMs or closed-back Argons. Open-backs are very good for a neutral reference but not close to being basshead even with a lot of power due to it’s design and how physics work.
So my suggestion is:
- Grab any Modhouse Argon’s for around $270-400 and Magni+Modi or any entry level da/amp from JDS Labs or other brands ($500-700)
- Grab the XENNS UP or EJ07M and Magni+Modi ($800-900)
- Or go big and invest in the Magnius+Modius and Fostex TH900 and never upgrade again ($2000+)
Yeah right the z1 was open the MDR is also closed 