This is a Review of Beyerdynamic Custom Street headphones with a Custom sound slider. http://north-america.beyerdynamic.com/shop/custom-street-black.html , available on Amazon: When it comes to full size headphones, there is not as much flexibility for sound shaping as you have it with IEMs. Besides a cable replacement, if supported, sometime you can try different earpads, if they can be removed and have a common shape/size. But that could actually affect the whole sound signature instead of a more focused sound change typical of IEM tip rolling (replacing different eartips). With on-ear headphones, quite often you don't even have a luxury of earpads replacement and usually at a mercy of a headband clamping force which can give you a better ear seal with a resulting deeper bass. To address this problem, two years ago Beyerdynamic released their original full size over-ear Custom One Pro (COP) headphones with a Custom Sound Slider (CSS). Later it was upgraded to COP+ with more customization options, though design remained the same. When I had a chance to test and to review it, I found CSS to be very effective in fine tuning the low end portion of the spectrum without affecting too much upper mids and treble. But despite their fun sound signature, I didn't find it to be as much fun wearing outside due to their large size. COP/COP+ design had a typical over sized DT-style earcups and headband intended more for a studio use rather than walking outside or while taking a public transportation. I'm sure Beyer received a lot of feedback about it, and responded back with a new Custom Street design which is a scaled down on-ear version of their COP/COP+ models. After spending a few weeks with them, here is what I found. Unboxing. If it wouldn't be for a smaller box, I could have mistaken Street packaging for COP+ because cover image has a very close resemblance to its full size sibling. Even the artwork on custom earcup inserts looked identical. On the flip side of the box you no longer see the "pirate" guy and instead there is a skateboard guy, more appropriate for "street" theme. The box also has a detailed info about Custom Slider, where you notice it has 3 positions instead of 4 like in COP. Also, you will find a detailed technical spec on the side of the packaging, along with close-ups of accessories where I was very pleased to see a carry case. Accessories. Custom Street comes with a nice selection of accessories which include a carry case, a removable cable, 8 pairs of double sided earcup faceplate inserts (for a total of 16 different designs), and a comprehensive user manual. The cable has a nice durable build, soft flexible design, with a round rubbery jacket, and universal in-line remote with a single multi-function button and mic. To eliminate the confusion with iPhone remote and volume control, Beyer used only a single universal Play/Pause/Call button which also works as transport skip control with double/triple clicks for both iDevices and Android. It was also a good idea to move remote/mic closer to the earcup to pick up voice better when talking. The cable has 3.5mm connector on both ends, where the side going to earcup is thicker with a basic slide-lock, which means the port opening is wide enough for any replacement cable with slimmer connector housing. The other side, going toward the source, has a connector with a slim collar to accommodate phone cases. Both connector sides have a rubbery housing with a nice grip. For a portable headphone cable this one strikes a perfect balance of being not too thick or too thin. It does have some microphonics, but it wasn't too bad. The hard shell case was a very pleasant surprise instead of a typical drawstring pouch. Even though by design Custom Street can fold flat, they also fold inside of the headband to occupy a smaller footprint. The case is moon-shaped and roomy enough to accommodate these headphones when folded in, even with an expanded headband. There was also plenty of room for a cable, though I would have loved to see a small mesh pocket on the side to keep cable organized and maybe to store a few of the earcup faceplates. Other than that, it was a rather nice case with a cool Beyerdynamic logo on top. As I mentioned before, replaceable faceplates were first introduced with COP/COP+, and now shrank in size with Custom Street. Since Custom Street overall design is a scaled down version of COP, you will find a similar earcup frame held down by 4 hex screws which you take off to replace a custom insert (hex key is included). The faceplate inserts are laminated cartons, and they are pretty durable. You can certainly use the default aluminum faceplate, or choose from a selection of 16 included designs, or maybe trace the shape/pattern and make your own faceplate. Either way, it's a nice touch to personalize your pair of headphones to give you some Street cred! Custom faceplates.