Be careful here. I would not use a 4in hose as the air flow resistance will be too high. It works just like a pipe where the larger pipe resist the fluid less. Same with wire carrying current. The idea you want is to allow full air flow but to absorb the noise at the same time. The sound will impact the insulation in turns but the air will flow around the turn easily. The sound wave is moving much faster than the air is. The larger the area for the air to move through the less restrictive it'll be. The more turns the sound has to make, the quieter it'll be. I prefer a 6 inch to reduce back pressure. I prefer 360 degrees of turns but 270 will generally do it if you need to direct the hot air a certain direction. The longer you make the hose, the larger the diameter must be to allow full flow.
Thanks for your input. But how do you mount 6 inch hose on antminer? Or you dont directly mount it on?
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