says amp recommended on headfi ive got the fiio e5 and the boost is ok for easily driven cans but i think maybe yours may need the extra power ,i also have the caffine ultra amp and i think that drives hd 650s maybe you can try afew different sources ,friends ect. The bass on my ultrasones is amazing even out of a d2 but they are only 32ohmns(i know this dosnt always meen easily driven)
heres the headfi article on good headphone and their amping requirements (maybe a little out of date)
Suggestion for amping:
"0" denotes amp usually included/bundled
"1" denotes amp not needed.
"2" denotes amp recommended.
"3" denotes amp required.
Under $70
IEM/Earbud
1-JVC Marshmallow (FX33, 34) ($15) Bassy, recessed mids and highs. I love them with rock. Great value. Kramer mod helps these a lot.
1-Creative ep630 ($23)
1-JVC Air Cushion ($30) These sound similar to the marshmallows, but with better detail and no recessed mids/highs.
1-Sennheiser cx300 ($30) Lovely midrange, and very strong bass (although uncontrolled) Highs are the weakness of this phone.
1-Yuin pk3 ($39)
1-Jays j-jays ($50)
1-Shure e2c ($60)
1-Crossroads Mylarone x3i/xbi ($57 and $65)
1-Yuin pk2 ($69)
1-Etymotic er6 ($70) Very detailed. Good mids/highs. Slightly lacking the bass department
1-Ultimate Ears Super.Fi.3 ($70)
1-V-moda Vibe($70) Very muddy, not a lot of detail. no highs to speak off.
2-Altec Lansing im716 ($100) Currently on sale @buy.com for $49
Open Headphone
1-Koss KSC75/35 (Clip-on) ($13) Very good value. Some bass bloat, good mids and sparkly highs.
1-Sennheiser px100 ($33)
1-Koss Portapro ($35)
1-Sennheiser HD515 ($60)
1-Grado sr-60 ($69) Wonderful liquid mids! Amazing with guitars. Not harsh to me, but to some. Lacking in bass.
Closed Headphone
1-Sennheiser HD201 ($22)
1-AKG k81dj ($54) Bassy dj headphone. Better with some damping. Good for rap and Hip-Hop
$70 to $150
IEM/Earbud
1-Sony ex90 ($95)
1-Jays D-jays ($99)
1-Westone UM1 ($109)
1-Shure e3c ($119)
1-Super.Fi.5 Pro/EB ($130-$150)
2-Yuin pk1 ($139)
1-Sennheiser CX95 ($140)
Open Headphone
1-Audio Technica ad500/700 ($100 and $130)
1-AKG 240S ($85)
1.5-Sennheiser hd555 ($95) Availalbe in 50 and 120 ohm versions.
1-Grado Sr80/sr125 ($95 and $149)
1-Alessandro MS-1
2-Goldring DR150 ($135)
2-Sennheiser hd580 ($160)
Closed Headphone
1-Sony Mdr-v6 ($71) A very neutral headphone. Good mids, highs. No bass bloat IMO.
1-Sennheiser HD280 ($80) Extreme isolation in a closed Headphone. Slightly anemic bass.
1-Audio Technica a500/700 ($98 and $140) Very balanced overall sound. Good for rock and metal. Speedy, controlled bass. Cheap pleather pads.
1-Equation rp21/rp22x ($85-$90) Plenty of awesome bass. Slightly recessed mids, good highs
1-Audio Technica ES7 ($110)
2-Beyerdynamic DT770 PRO ($150) Bass monsters! Also a good gaming/movie watching 'phone.
1-Denon d1000 ($130)
$150 to ~$200
IEM/Earbud
1-Shure e4c (~160)
1-Jays q-jays ($170)
1-Atrio M5/M8 ($180)
2-Etymotic ER4p ($180) Very detailed, awesome highs and Mids. Bass is lacking to some. Sound is wonderful with a Mini-box E amp (Bass boost)
Open Headphone
2-Sennheiser hd595 ($180) Available in 50 and 120 ohm versions
1-Grado Sr225 ($180)
2-AKG k501 ($190)
3-Beyerdynamic DT880 PRO/2005 (~$200)
Closed Headphone
2-Sennheiser HD25-II ($175)
1-Audio Technica a900 ($200) Massive soundstage, strong bass, and comfort are its strong points. Great for movies and jazz. Slight weakness in the low-midrange. Crappy pleather Pads.
2-Beyerdynamic Dt250 ($200)
2-AKG 271s ($185)
$200 to $300
IEM/Earbud
0-Stax SR001/003 ($230)
1-Shure SE530PTH ($280)
1-Earpiece Livewires ($250 plus impressions)
1-Ultimate Ears Triple.Fi.10 ($299)
1-Westone UM2 ($299)
Open Headphone
2-Sony Mdr-F1 ($240)
3-Sennheiser HD600 ($240)
2-Grado SR-325i ($249) Most aggressive Grado. Sharp metallic sound with fast attack + decay. Great pair for electric guitars.
3-Beyerdynamic dt990-2005 ($250)
3-AKG k701 ($250) Detailed phones with wide sound stage. Amp dependent for good bass. Often compared against HD650.
1-Ultrasone PROLine 2500 ($263)
2-Audio Technica ad1000 ($330)
2-Alessandro MS-2i ($299)
Closed Headphone
2-Denon D2000 ($260)
2-Ultrasone PROLine 750 ($263)
?-Audio Technica ESW9 ($280)
$300 to $500
2-Headphile Darth Beyer ($370 to Whatever you can imagine!)
IEM/Earbud
2-APureSound Etymotic Er4p
?-Klipsch Image ($350)
Open Headphone
3-Sennhesier HD650 ($325) Dark headphone with ample bass. Very amp/source dependent. A whole new level of awesome when balanced.
0-Stax SR303 ($350)
2-Sony SA5000 ($350)
2-Grado Hf-1 ($350 to $400)
0-Stax SR404 ($450)
2-Grado Rs2 ($495) Liquid mid-range and if used with flat pads, slammy bass. If 325i is too sharp, this is the 'phone to go for.
2-Audio Technica AD2000 ($499)
0-Sony Pfr-V1 ($499)
Closed Headphone
3-Audio Technica w1000 ($399)
3-Denon D5000 ($559)
More Than $500
IEM/Earbud
Westone ES-2
Ultimate Ears UE-10 pro ($900 + Impressions)
Ultimate Ears UE-11 Pro ($1,150 +Impressions)
Sensaphonics 2X-S
Open Headphone
2-Grado Rs1 ($695)
2-Alessandro MS-Pro ($699)
2-Grado GS1000 ($995)
2-Grado Hp-2 (~$1400)
3-Grado Ps-1 (~$1400)
0-Stax Omega 2 ($1850)
Closed Headphone
3-Audio Technica w5000 ($699) Woody headphone which is known for troublesome fit and being picky about amplification. If used successfully - very worth the trouble.
3-JVC/Victor DX1000 ($889)
2-Ultrasone Edition 9 ($1,499)
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