[WoahReQQuiem]

Do get the FiiO E9 dock for the E7, it'll provide great amounts of power for the Pro 900. 
And if you'll need a more powerful portable, the iBasso D-Zero / FiiO E11 can do the job.
Quote:

thanks for all the help guys. if i can sell my beats i will go ahead and get the Ultrasone 900s and the E7 amp. I'll report back if i do!

 

 

[funkmeister]

You guys crack me up. The Ultrasone specs are 40 Ohm impedance and 96 dB SPL. Amping is not an epic improvement unless you have a current buffer amp.
 
The Ultrasones will sound much better than the Beats, though their headband is hit and miss with folks. The AKG's are downright huge with a broader headband, but they have flat bass, so coming off the Beats they'll sound shrill and anemic at the same time... though they're actually fine. If you actually liked your Beats (which many do) then don't get the AKGs; they're too real. The Ultrasones will be spectacular and are actually portable. The S-Logic is awesome. It's the only thing that can really rival AKG's wide soundstage. Anyway, they don't really need amping to sound good, but they make use of amping to sound a bit better, especially with quiet tracks.
 
I've seen a very detailed electrical analysis of FiiO products and the E7 is by far better than the E11. The output impedance of the E7 matches the Ultrasones perfectly... much better than if you mate it to the E9 dock. The S-Logic will be your best friend with the E7.
 
Also, the Ultrasone Pro 650's or 750's sound VERY similar for less money. So if you're feeling the squeeze, they're great options.
 
Enjoy!
 
Oh, if you like the Ultrasone sound but want some semi-open cans, then the Pro 2900's are good, as are the AKG K240 or K242 headphones... very similar in sound and detail. The AKGs aren't portable, though. They also look a little funny but they are probably the most comfortable headphones on earth.

 

[gustavthelion]

Thanks for all the info! I've already ordered the iBasso D-Zero will that be worse than the E7 with ultrasone 900s?

 

[gcameron]

i have the ultrasone pro 750 and i use the cheap and cheerful FiiO E5 which really makes quite a difference and isnt bank breaking.
 
still burning them in but each time i put them on they sound better each time

 

[Coq de Combat]

I can add that the E11 and E10 are good matches with the Pro 900.

 

[funkmeister]

The iBasso D-Zero has a good current delivery, so you should be fine if it's implemented well. I don't know what the output resistance is. It wouldn't be good if they exceed 5 Ohms. Unfortunately, it's very likely that it does because the AD8656 is designed to feed loads of at least 1k Ohms. If I understand correctly, it's actually designed as a DAC buffer to feed automotive head units. In fact, I couldn't find a noise performance measurement that wasn't at least 1k impedance. I found 1k, 2k, 10k, 1M. Any of those will put your damping factor down in the low fractions territory instead of the ideal >8:1. So linearity would suffer making the bass less controlled. Coming off the Beats, you wouldn't know you're missing anything anyway, so see if you like it. It might be fine. Since they advertise 8-300 Ohm loads, you're probably just fine. I don't mean to scare you. I can just nerd out sometimes.
 
The FiiO E7 (not E9) has super low output impedance <1 Ohm, so we know that it's a good fit.

 

[gustavthelion]

So I've had the Ultrasone 900s and the iBasso D-Zero for a few weeks so i thought i'd come back and report. firstly, thanks all for the help! And I absolutely love these headphones, I can finally listen to something other than Hip Hop loud! All genres of music sound amazing honestly. Although regarding the amp I will say that it isn't the most useful thing. Directly plugged into my iPhone i can hear no difference in sound quality between that and through the amp through the LOD cable, even if the amp can get quite a bit louder. One bonus of the amp i'm seeing is that if I use the LOD cable and the amp then listening to music seems to only drain my amp's battery and hardly effects my phone's battery which is really nice- i don't need a secondary player anymore. I would like to note however that even though the sound directly from my iPhone's audio jack may be quieter i cannot tell any difference in audio quality when listening through the LOD and amp

 

[LithoJazoSphere]

Quote:

I've seen a very detailed electrical analysis of FiiO products and the E7 is by far better than the E11. The output impedance of the E7 matches the Ultrasones perfectly... much better than if you mate it to the E9 dock. The S-Logic will be your best friend with the E7.
 

 
This is quite surprising.  Everything I've read and my ears tell me that the E11 is superior to the E7.  Both have an output impedance of <1. 

 

[skiam]

hey 
 
i've had the Pro 900s for almost a year now and I love them, but I just sometimes wish for more "umpf?" in vocals when I'm listening to like Adele or slow RnB songs. Beyond these, I mainly listen to Kpop (all kinds), classical, and lots of ballads. Would the K550 answer my wish for that extra "wow" factor? Sometimes I get bored from my Pro 900s sounding too hollow in a sense, maybe due to a lack of a good amp. I certainly hope K550s would be an improvement when listening to the genres I mentioned before.

 

[Watchmaven]

No they won't give you the WOW you're looking for. The detail and soundstage is wonderful but the lack of powerful bass can be a let down for the first couple of listening sessions. Don't get me wrong, the bass is accurate and tight, just not deep. Thicker firmer pads and a headband with better clamping would make the 550 close to perfect.
 
I've been warned off the Ultrasone by many experts but I keep coming back to them, so I'm going to order one to try. Only one will survive the cut.

 

[cyberalpha11]

In term of sound stage, separation & mids- high, does AKG K550 perform much better than Ultrasone Pro900 S-Logic?