Well, I was away for most of the weekend, so I didn't want to post anything too long winded, but:
I have also had these pads now for a little bit of time. I'll go ahead and give my impressions here after many many hours of listening:
New pads presents a much stronger and a clearer case of treble and midrange. Midrange has especially gained a noticeable increase in quantity and quality. It has more texture and more detail. The treble is also clearer and not as muddled over by the bass. The bass has taken a step back around 100Hz, and it's not as bloomy overall. The bass is smoother overall tighter, controlled and really for intents and purposes can only be described as sounding "ortho". The texture and detail in bass is really hard to get from a dynamic driver, and the new pads really make the quality of the bass shine.
I always thought the MD had a fifteen foot soundstage in each direction, which is pretty darn good for a closed headphone. Within the 15’, the instruments could be easily picked out in an exact position. With the new pads, that 15' wall seems to drop away and the space really stretches on.
Here are some genre specific notes I jotted down
Electronic: (Track: Ovnimoon – Turn Off the Light)
Mad Dogs: More bass punch upfront. It’s subtle but definitely more powerful, but a little muddy.
Alphas: Bass is much more controlled, and shows transparency. Still powerful, impact and hard hitting, but not as bloomy as the mad dog pads.
Rock: (The XX – Sunset, The Airborne Toxic Event – Live album)
Mad Dogs: More presence in the strings. Indicates to me a slight kick over the alphas in the 80Hz-180Hz range
Alphas: Warmer, smoother presentation in vocals and all midrange/treble areas. The more controlled bass really benefits the bass guitars and classic stringed instruments to give them more texture. Clear improvement in instrument separation.
Jazz: (Jazz at the Pawnshop, Muddy Waters)
Mad Dogs: Separation is really shown in the Jazz mixes.
Alphas: Strong instrument separation and soundstage opening. Treble and midrange are much more balanced, and treble is definitely less fatiguing. Once again, love the string presence here.
Female Vocals: (Norah Jones, Joni Mitchel)
Mad Dogs: Recessed vocals, to the point where they start to sound a little thin
Alphas: Much more fullness, warmth, really an enjoyable presentation to listen to
My impressions are very similar except I definitely find the bass with the alphas to be a little looser and bloomier than with the dog pads. Some may hear this as superior though. That's really the only area where I might have some reservations. The highs are definitely crisper yet non fatiguing. The isolation is at least as good if not better than the dog pads. They're comfy. They smell nice and leathery!
Does anyone know if it's possible to experiment to try and cut some of the bass bloom back down by putting some (or all?) of the white foam back in with the alpha pads in place?