Books can definitely be expensive but they're one item on an ever shortening list of things that corpos can't claw back from you after purchase. For that reason, they're money well spent if you ask me!
AstralPath
Yup. Limitation just 'cause. Capitalism at work.
Pro tip for drummers: buy this instead of moon gels, cut them to whatever size you need for the dampening you want.
The palm makes for good batter head dampening, the fingers are great for resonant heads.
They work great and they're dirt cheap!
All I can give you is an anecdote about my own experience. In said experience I've not had any non-starter issues with those two tools. They work for me until Youtube changes its algorithm.
This is why I mentioned the NFL channel as an example. It's my canary in the coalmine of Youtube. When the NFL channel (among other sports related channels) pops back up on my feed, I know that YouTube has changed something in the algorithm.
I just click Not Interested and Don't Recommend Channel and away it goes for another year or so until they make another change. Simple as.
I've curated a recommendation feed that is highly specific to my interests as a result. Not sure why that method wouldn't work for you.
They definitely do because my recommendations are squeaky clean 98% of the time and those buttons, along with not clicking on shit that I think will poison my feed are the main tools I use to keep things clean.
One thing to keep in mind is that YT makes changes to their algorithm every once in a while. For me, that typically manifests as sports channels, especially the NFL, or political stuff making their way into my feed. A few clicks of those buttons and I'm back to normal.
The Not Interested and Don't Recommend Channel buttons work surprisingly well for this. I am very protective of my algorithm so I try to avoid videos that I think will open up the flood gates for shitty content but in the event that it does, a few choice clicks of those two buttons usually has things bavk under control pretty quick.
Thats not dispositive of the fact there is very much rhythmic/aural entrainment.
As I mentioned, I didn't find any official sources for that. I won't claim they don't exist, but the fact that research on that topic is harder to find does not work in favor of its validity.
I like it and I think it is relaxing.
I think this is all that you should be concerned about. If you like it, there's no harm in enjoying it as much as you like. Sometimes the mystery is the magic, y'know?
Entrainment is most strongly related to light exposure, meal timing, and resource access.
I struggle to find anything related to audio.
Additionally, your headphones/phone/speakers do not have the ability to generate a 1hz tone with any power as to be noticeable or effective in any way. If anything can be tied to 1hz in the audio you're listening to in these videos it would be higher frequency tones, chords, or sounds that have a pattern that repeats once per second.
Safe speeds are not whatever speed is comfortable to drive a given street. Part of the posted limit is considering how much of a wrecking ball a vehicle would be if it suddenly left the road.
The limits in suburbs where I live is 50km/h. The roads are wide enough to land a plane on and you could very easily drive most of them full throttle as they are flat and straight. With that in mind I still think it should be 30km/h.
When I was a kid a car hit a snowbank and was launched straight into someone's living room not far from my house. If they were driving 30km/h, that nightmare scenario pretty much becomes an impossibility.
We just need to stop making residential roads that look like drag strips. More curves, more trees close to the road, more speed bumps. I've driven in some places in Europe where it's very clear that it's unsafe to drive any faster than about 30 km/h due to roadside obstacles. I think that design is much safer than the NA standards.
You're telling me you can't get a hold of an HM-2 and a Peavey Rage 158 or a Bandit? Three of my friends had the Rage 158 as their first amp and you can just buy an HM-2 on Reverb if you don't know anyone that already owns one.
People have recreated the LHP sound countless times. Entombed is not the only band to ever do it.

I've always wanted a massage table so I could lay flat on my stomach with my head in a neutral position and read by looking through the hole.