Reddit mentions of AmazonBasics Foam Yoga Blocks - 4 x 9 x 6 Inches, Set of 2, Black

Upvote for Meddle! YNWA!!

After you get those speakers up off the desk, like u/sharkamino says, get a better cartridge for turntable. I'd recommend the Nagaoka MP-110. It's a great cart for the money. Very detailed and a little bit warm. It's available on Amazon for about $120. You'll be stoked listening to Pink Floyd with it.

NAGAOKA MM (MP) Cartridge MP-110 https://www.amazon.com/dp/B002SDU67Y/ref=cm_sw_r_cp_apa_i_XtnMDbCAJVSH6

To get your speakers up:
AmazonBasics Foam Yoga Blocks - 4 x 9 x 6 Inches, Set of 2, Black https://www.amazon.com/dp/B01FN7X7KE/ref=cm_sw_r_cp_apa_i_TvnMDbK4BNNTZ

These work great and are cheap and you get two. https://www.amazon.com/gp/product/B01FN7X7KE/ref=s9_acsd_cartx_hd_bw_bEMHv_c_x_w?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=merchandised-search-3&pf_rd_r=3PCPG2VCEVW5F40WA87N&pf_rd_t=101&pf_rd_p=b4aea1b3-e669-56a4-a25f-0b17678c0d05&pf_rd_i=3422271&th=1

All hard disk boxes are noisy. I put mine over a yoga block to reduce vibrations. https://www.amazon.com/AmazonBasics-Yoga-Blocks-Set-2/dp/B01FN7X7KE/ref=sr_1_8?keywords=yoga+block&qid=1554896322&s=gateway&sr=8-8

T-shirts are fine, they're all I wear. You just have to get the holster oriented correctly so that it's not pressing outward against the t-shirt, and is instead softly pressing into you so that the shirt drapes over it inconspicuously. I can't see what's going on under the shirt in those pictures, but it looks like there are two "hot spots" where the gun is printing—one at the base of the grip, and one at the rear of the slide. I have two recommendations:

First, the Vedder Light Tuck is available with and without a "claw" attachment. Again, I can't see under the shirt, but I'm guessing because of the way the base of the grip is poking out that you aren't using the claw. They sell them as an add-on kit for 9 bucks (https://www.vedderholsters.com/claw/), so I think it's worth it to check that box.

The bigger problem, though, is that it looks like the whole gun is allowed to tilt outboard; if you look under that shirt, I bet you'll see that whereas the muzzle end of the gun is touching you, there's a gap between your belly and the top of the gun, or at least there's more pressure against you at the muzzle end than at the top. That's the opposite of what you want for concealment purposes—the more the gun tilts out at the top, the more it presses outward on your shirt and looks obvious.

Since you're a leaner guy, you might find that the wedge kit sold by JM Custom Kydex (https://www.jmcustomkydex.com/p/NSWK.html) is the right size for tilting things back in a good direction.

I'm heavier than you and found that I needed a different solution with more material than that, so "the yoga block mod" (https://youtu.be/E4HD4J37u6I) that Scott Jedlinski advocates was necessary. The idea is that you get a big block of foam (any relatively dense foam will do but here's a link: https://www.amazon.com/AmazonBasics-Foam-Yoga-Blocks-Inches/dp/B01FN7X7KE/) and sculpt it down until it fits the shape of your body and orients the gun perfectly for concealment. It's a touch more work, but it obviously tends to yield better results because it's a completely custom solution that you build for your exact body, sort of like tailoring your clothing.

I think just put the right one on one of these and the left one on one of these and you'll be good. That will fix the height issue as well as the vibration dampening issue.

Ah, yeah the cord for those is pretty short. Oh well.

So a pretty big problem with active speakers, as you found out, is the constant buzzing from them. You can't stop this. It's really common in active speakers.

Yoga blocks

https://www.amazon.com/AmazonBasics-Foam-Yoga-Blocks-Inches/dp/B01FN7X7KE

https://www.amazon.com/Technical-Pro-Bookshelf-Computer-Multimedia/dp/B07CJ544J7

these DIY Look Good

https://www.youtube.com/watch?v=0iPxsgyvtwA

Like everyone else is saying, it won't help much for soundproofing, but if you still want to try it, just cut up some yoga blocks. I have them under my 2x 18" subs. https://www.amazon.com/AmazonBasics-Yoga-Blocks-Set-Black/dp/B01FN7X7KE/ref=sr_1_4_acs_sk_pb_2_sl?s=exercise-and-fitness&ie=UTF8&qid=1540925124&sr=1-4-acs&keywords=yoga+block

https://www.amazon.com/AmazonBasics-Yoga-Blocks-Set-Black/dp/B01FN7X7KE/ref=sr_1_9?s=exercise-and-fitness&ie=UTF8&qid=1549500979&sr=1-9&keywords=yoga+blocks

Impressions?

Cheap (0,30 bucks), but effective.

This is my second stand for my m40x after the boom of threads showing the luxurious or pretty damn cheap headphone stand as part of a meme in this community.
I want to imply that it not nessesary to have one of these but you can also look for other options like zeos with his yoga blocks and stay cool without deform the headphone's shape.