So, here is a quick and dirty video of this quick and dirty mod. Together with the descriptive post I put up earlier, I hope it'll make things clearer. The holes in the inner foam are from before, if this is your first time, gently poke around until you find the screw holes, using the images as a guide. Of course, this will void your warranty, so don't try it at home unless you really wanna.
The sound.. hm, it's much more fun (and by that I mean bassy), the soundstage is bigger and better IMO, instrument separation also improved. On the other hand, you might find the bass a bit too much now, compared to what it was before. I think this is a highly subjective call, so try and see what works for you. Of course, you can experiment with covering holes with different materials and in different ways.
I've tried putting some cotton wool between the two enclosures and found that it absolutely kills the sound, making them sound like 5$ headphones.
Have fun and be sure to share your findings.
Here's the video: link.
Hey ZMD, instead of putting the mesh over the middle hole and leaving the side hole open, try leaving the middle hole open and putting the mesh over the "front" hole. The bass is much better controlled this way and I would argue it helps with damping, the achilles' heel of the HD448. With this modification, it brings it closer in quality to my HD580's with the HD650 stock cable and HD600 rear grilles, if not to the level of the aforementioned headphones with the Cable Pro EarCandy headphone cable upgrade.
Just did what you said and I don't really find much of a difference yet between the two options you mentioned. This setup, however (one hole open, one sealed and one with the original mesh on) seems to be optimal for full, if a bit boomy, bass and balanced sound. I tried covering two holes with mesh and leaving one open, bit it cuts the soundstage down to almost original levels, with not much improvement to bass. I'm really digging the wide sound and don't think I'll be going back to the original.
The option I mentioned seems to make a subtle difference in the clarity of the bass attack to my ears. The method you originally mentioned seemed to be more "fuzzy" and indistinct in the bass note attacks, much like the HD238. Either way, it does seem that it makes an improvement over the original mesh-only configuration. Thanks for sharing your findings and this mod.
I just got the HD 448s, and based on above comments I see that an amp would improve the sound on ipods? Any recommendations as to which ones to get? The ones from HeadRoom are out of my price range...
I am looking for portable ones... My budget is around $20-40
I see some Fiios on amazon like Fiio3 and 5, also the cmoy amps look pretty interesting but I don't if they are gd or not... and I dunt really know where to get them either
I have a FiiO E5 that's currently being shipped to me. I'll report on my experience when it gets here.
As for the bass port mod, I have to say I've gone back to stock. It's the only configuration that gives me good detail across the spectrum, and while the HD 428 is light on bass, it's definitely not missing any except for the lowest of frequencies. If I ever feel the need for a bit of added kick, there's always the bass boost on the FiiO.
I've reverted to stock too, but only now I realise that I'd been missing big bloated bass because of listening to sony IEMs for 3 years almost daily. The lows on the HD448 are great for bassy music (because they're so tight and fast), but they're outshined when it comes to more complex stuff, when all the frequencies come into play and the mids dominate.
Yeah, I wish there were a way to control how much bass is increased.
My main issue with the bass mod was distortion. For tracks that are light on bass, it was great, but most of my techno tracks were reduced to a mid-bass distorted rumble. It wasn't exactly clean bass, sadly.
Hey guys, I am a new guy here. Is there anyone tried Sony MDR-7506/V6, HD 448 and HD 555? I am currently struggling to decide which to buy. I don't have a headphone amp. All I want is just excellent sound. Any advice? My budget is around $100-150.
For serious bass go for Sony, for seriously better sound regarding neutrality and clarity consider the Sennheisers. The Sony MDR V6/7506 can be good, it's just that you really have to like the sound, audition the Sony headphones if possible. Always audition if possible...
P.S. Welcome to Head-Fi and sorry for your wallet...