While any avid head-fier is likely to know of at least one, if not multiple versions of a modified Fostex T50rp, knowing which versions are likely to fit one's personal preference is a whole other story. If you like rich mids and a little heft down south, Mad Dogs are likely to please. A more neutral tuning? LFF is your guy. Somewhere in between has largely been filled by the excellent ZMF Master Model. However, there is a newcomer who's made quite a name for himself as far as I'm concerned. He's a head-fier and he goes by PETEREK. His modified T50rp (I'm told a snazzier title is forthcoming, but for the remaineder of this review, I'll call it the PTKT50) bests all of the above headphones to these ears. But that's just the tip of the iceberg. Not only do they sound awesome, but they are extremely customizable, more comfortable than the competition, AND priced firmly in the middle of this tier's price bracket. So without further ado, let's get to it! The Breakdown
Test Songs (all FLAC either 16/44 or 24/96):
The Curtain - Snarky Puppy & Metropole Orkest - Sylva
Love Yourself - Justin Bieber - Purpose
A Good Name - Shad - TSOL
Lightning Crashes - Live - Awake: The Best of Live
Strasbourg/St. Denis - Roy Hargrove Quintet - Earfood
You Go to My Head - Lauren Desberg ft. Gretchen Parlato - Sideways
Too Close - Alex Clare - The Lateness of the Hour
MBP > JRMC > ALO Pan Am
MBP > JRMC > DACport LX > MAD Ear+ HD
Before we jump into specifics, I need to clarify something: the PTKT50 is not a mass-produced product. There are really only a few out there thus far. PETEREK is a fantastic modder who's work is not only legendary, but also wonderfully unique. Knowing that you're rocking a headphone that no one else on Head-fi has is a pretty sweet feeling!
So for the sound...
Overall tuning: largely linear (check out the graph), which a little extra bump in the trunk and sparkle up top. Somehow PETEREK has found a tuning that stays true to hi-rez recordings, but also insists that you bob your head while listening. Quite the feat if you ask me!
Bass: From another review of mine: "Full and textured. I've learned that my favorite bass presentation is that featuring a present sub-bass sound, with a slight mid-bass boost. This makes kick drums a little more felt than just heard and works better for lower level listening." The PTKT50's bass bears a large resemblance to that of the HE500. Goes deep and still hits pretty hard. The 500s low end is a little less aggressive, but that's not to imply that PETEREK's work is worthy of the basshead title. It's the kind of low end that brings funky bass lines (like those in the Snarky Puppy) up front, and drops it hard when the chorus from Mr. Clare comes up!
Mids: Smooth and clear. The mids on this headphone rank right up there with those found in the Mad Dog. Very smooth, and free of muddiness. Electric guitars have crunch, male vocals are nice and full, and the airy, breathy voice of Lauren Desberg is just gorgeous. To these ears the lower mids don't differentiate from the mid-bass quite as well as say the ZMF or HE500, but that's just me being picky. I will say that the PTKT50's mids sit just slightly behind the frequency extremes. They certainly aren't recessed or unnatural in any way, but they definitely aren't uber-lush or forward like a Grado or HD600. Check out all the subtleties in Bieb's new jam:
Treble: Crisp and crunchy! Based on my experience and readings, one of the harder things to nail down using the T50 drivers is the treble range. It's prone to being utterly subdued or overly peaky and disjointed. I felt like the upper end in the Mad Dogs was a little too polite and even though the ZMF got closer, it still didn't dig out the details that a comparably priced open-back could. Well, I'm here to tel you that the upper end in PETEREK's mod is the best one yet. It's got great extension and clarity. Intricate cymbal play and electric guitar strums are wonderfully realistic and the zingy electronics in the Clare and Shad are just groovy! My only qualm with the treble (and really with the whole package) is that the treble can get a little zingy. Just a hair spicy. Now I didn't feel that way as much with warmer tubes in the amps, or with songs that have a smoother top end already, but with more neutral source material and/or amplification, I found the very top end a little fatiguing.
Soundstage/Separation: Both are very good. I think that the tuning allows for a larger-than-average soundstage, especially for a closed back. Definitely more depth than width. Not quite as realistic as the ZMF Master, but I've certainly not felt like I've been shortchanged in the soundstage department.
Non - Sonic Commentary: If you haven't already, check out the pictures below. PETEREK has recabled, repadded, and revented a stock T50rp. He's painted the cups, tuned and retuned the internals, and installed LEMO connectors (which are pretty freakin' sweet). To say that the PTKT50 is customizable would be an understatement. I'm sure that if you've got an idea for parts or mods for the T50, PETEREK will hook you up! He even removed the stock Fostex headband covering to reduce weight! Brilliant!
Conclusion: All in all, you can probably discern that I'm a fan of PETEREK's Modified T50rp. It's been my favorite T50 mod out of the three I've heard. It's got sweet looks, a sweeter price tag, and an even sweeter tuning. For EDM, pop, rock, or jazz listeners, I think this is the T50rp variant for you. For those who are married to neutrality or classical music, the ZMF may be the way for you to go. But all things considered, PETEREK has created a fantastic closed can that will offer the listener a one of a kind headphone who's great looks are only bested by it's excellent sound!