[ErnestPoland]

I recently purchased the MDR-XB50AP and I am pretty surprised about the sound quality. I always put the EQ on every sounding device I own (that is with my ATH-M50X and that was with my studio monitors earlier). So I've took them and first I wanted to listen to it without any EQ and try to compare to other things. So in raw, they have a little bit muddy but detailed sound. I like crystal hi's and meaty mids and low-mids. They have punchy bass, but they lacks that cleanliness. So I've set the 250Hz-2kHz freqs a bit around +0.5dB to +1dB, 8kHz a bit more (around +2dB) and 16kHz even little bit more. Now they sound really clean and also they have punchy lows.
For the price I've purchased it ($40 after taxes, in Future Shop), they sound really good, and they are loud too.

 

[Xeroday]

I have a pair of Sony MDR XB50AP and they have so much bass (probably 50% more than the Sennheiser CX 300 II's). When I first used them, the bass was uncomfortably strong. With their huge drivers, you really feel the bass inside your head. 
 
The sound quality on them is pretty good -- similar to Klipsch S4's, just a lot bassier. I would still probably choose my S4i's over them, just because they're more balanced. The huge drivers also cause the earbuds to protrude out twice as much as the Klipsch S4's, which kind of looks weird.
 
But if you want a pair of low cost, very bassy IEM's, this is probably the one to get. You can find them for as low as $15 on eBay (Open box), which was fine for me, since Sony's manufacturer's warranty was only 90 days anyways. 

 

[Mark Up]

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[Baseman]

• Calibration graphs from Golden Ears ('SPECIAL THANKS'). If you have a 'Q' setting found in your EQ options set it to 4.3. Refer to my UPDATE post.

Frequency Original Applied Difference
32Hz +6.5 +2.5 -4.0
64 +9.0 +1.5 -7.5
125 +10.0 +0.5 -9.5
250 +6.0 +0.5 -5.5
500 +0.5 -1.0 -0.5
1000 +1.0 +1.0 +1.0
2000 -5.0 -2.0 -3.0
4000 -8.0 -1.0 -7.0
9500 +2.0 +3.5 +1.5
16000 -14.0 -14.0 -14.0

Q Factor = 4.3 (1/3 Octave)

 

[p4s2p0]

The xb70bt have amazing sound better than my old urbeats or xb50ap, and the 9hr battery life rating is awsome. They have HD voice for calls too

 

[Baseman]

Changed the low and high end filters to zero since this is considered 'No Guarantee Area'

 

[Baseman]

Actually had to revert changes and bring the high end to 0, low end back to -2.5. Man, am I having fun learning this calibration stuff!!!

 

[Baseman]

UPDATE: I seem to have overlooked several things and do apologize! GE calibration is done with a 'smoothed octave 1/3' and since I didn't see it mentioned in their 'FR Comparison graph' I understood to the leave 'Q Factor' off or at its lowest. NO, it should be set to 4.3 as indicated by the 'Q Factor' I posted above. It is very important that if you use any calibrations that are done with any type of smoothing, you need to apply the very same factor in your EQ device.

 

[bukowski]

I've bought the XB55 and want to buy some memory foam tips for them. can you guys give me some advice with the size? T200?