Due to extensive similarities between the GSP 500 and GSP 600 in terms of design and construction, I have no choice but to rehash some of the stuff I wrote in the review of the GSP 600. Upon closer examination and a direct comparison, I did discover some subtle differences (not counting the ear cup design) I will cover below.
The Sennheiser GSP 500 is a massive headset. Its ear cups are huge, and the same could be said for the headband. When you put it on your head, there's enough room between your head and the headband to fit in your hand, which should give you a good idea about the size of the GSP 500. It's about 40 grams lighter than the GSP 600 due to the ear cups being perforated. Regardless, 358 grams of weight is nothing to laugh about. Luckily, comfort isn't an issue at all; we will get back to that on the next page of this review.
This is, in a nutshell, the most dramatic key difference between the GSP 500 and GSP 600. The GSP 500 (pictured left) has perforated ear cups and, as such, sports an open-back design. At a certain angle, you can clearly see the speaker drivers through the metal mesh. Compared to that, both ear cups of the GSP 600 (pictured right) are completely sealed. Sennheiser opted for a combination of robust, flexible plastic and a couple of metal parts, such as the silver element that connects the ear cup to the headband and the red ring that surrounds the joint of the pivotable microphone. Two additional red stripes can be seen on the arm of the microphone.
The ear pads are different as well. While the GSP 600 (pictured right) uses a combination of pleather and suede, the ear pads on the GSP 500 (pictured on the left) are made entirely out of fabric and slightly thinner. As I mentioned in my GSP 600 review, Sennheiser claims that the purpose of suede is to prevent the ear pads from sticking to the head when gaming in a warm room. It could be argued that such a solution isn't needed because of the open-back design of the GSP 500—we have much more airflow and the ears don't get nearly as warm regardless of the environment.
The right ear cup contains a large wheel that acts as a volume dial. Its circular motion is silent and quite refined, so I had no trouble making even the tiniest of volume adjustments. If you rotate it all the way in a counterclockwise direction, the sound will be completely muted. Accurate and easily accessible, it's a great volume dial.
Staying true to their gaming headset design, Sennheiser integrated the microphone mute function into the microphone itself. If you don't want it to pick up any sounds at all, you can simply pivot it upward. The first photo shows the exact position where a faint "click" can be felt and heard, which will tell you that the microphone has been muted. When you want to use it again, all you have to do is pull it down until it lands in front of your mouth. The microphone's range of motion has been implemented in a similar fashion to that of the volume dial, both in terms of smoothness and accuracy. Once you put it where you want it to be, it will stay in that exact position until you manually change it.
The microphone capsule seems to be quite large, and I'm expecting it to sound just as good as it did on the GSP 600.
One feature that wasn't previously present on Sennheiser's gaming headsets was the ability to adjust the tension of the headband, which, as a result, changes the clamping force. There are two sliders that can be moved to the left and right now. By moving these, you actually change the tension of the "invisible" inner metal headband the sliders are attached to. The tightness of the grip increases as you increase the distance between these sliders. Meaning, if you want the headset to be as loose as possible, which was my preferred setting—one that resulted in fantastic wearing comfort—the sliders should be positioned as closely to one another as possible. We already saw this exact solution on the Turtle Beach Elite Pro Tournament. It worked great there and works great in the case of the Sennheiser GSP 500 (and GSP 600) as well.
The braided cable is detachable, but you won't have an easy time using just any audio cable you have lying around in its place. The hole with the connector is quite deep, and the connector itself is 2.5-mm instead of the more common 3.5-mm. In other words, Sennheiser wants you to use their cables.
Two cables are supplied with the headset. One of these is 2.5 meters long and terminates in a pair of 3.5-mm 3-pole TRS plugs. That's the one you'll use for devices that have separate microphone input and headphone output, such as the integrated sound card of your PC. The second cable is 1.5 meters long. That one terminates in a single 3.5-mm 4-pole TRRS plug and is supposed to be used for consoles, mobile devices, laptops, and other devices with a combined audio input and output.