It's information we gathered over a span of about 3 years in the Audio/Tech section. We noticed that if a person only used 1 layer of moving blankets, there was still reverb. 2 still had reverb. 3 got rid of most of them. And these were standard 72 X 80, 12 pack, 2.75 pounds each, ie 40 lb/dz.

Basically we discovered the following:

1. Always use 1.5 inch pipes. If you're going to use thinner pipes, you really want to add more pipes.
2. Use clamps to hold the blankets together.
3. Go 3 layers per side if you use generic moving blankets that are 2.5 pounds each. 2 layers per side if you use SureMax Ultra Thick (must be the 5 pound version). https://www.amazon.com/Sure-Max-Moving-Packing-Blankets-Professional/dp/B07CJHGP6S/ref=sr_1_2? Use 1 layer per side if it's VocalBoothTogo. If in doubt, add moar.
4. Best minimum dimensions are at least 4 X 4 X your height + 1
5. Vocalboothtogo does not pay for shipping. Suremax gives free shipping via Amazon.
6. Never buy moving blankets from Home Depot or Lowes. Buy them from Amazon instead.