Hi all.
Just wondering if someone could shed some light on this. As a beginner on the bass we are told to have our thumb on the fretting hand on the neck of the bass.
I was watching this video of Mike from Green Day and it seems he uses his thumb on the E string quite a lot.
I also noticed the bass player from Architects also uses this method.
As a beginner I don’t want to get into bad habits but I was just interested in why they do this?
Thanks
@Ludders
Hello. I’m a beginner as well and loving it so far.
I started Josh’s B2B course and am currently in Module 3. In the course (at least what I’ve seen of it so far) Josh talks about where to rest your right thumb. Basically, it depends on what you’re playing.
It kind of goes in this order:
@Ludders
I just re-read your original post and realized you’re asking about the fretting hand… sorry about that.
Josh talks about keeping your left thumb loose, and along the back of the neck, not grabbing the top of the neck. That’s all I can say as I’m pretty new, hopefully someone will shed more light on your question.
It looks to me like he is using his thumb to mute there.
A few observations:
I agree, I believe he is muting with his thumb.
Do as Josh (and all instructors) say and keep your thumb on the neck until you have developed as a player, and then you can experiment with using your fretting thumb for muting.
Yeah… agree Pam. I keep it on the back of the neck.
I could never use that “death grip” as I call it, on my bass or when I play guitar, just doesn’t feel right, very awkward. My hand can’t move that way anyway. I refuse to choke my instruments, they deserve better. 
This approach is real real common in aggressive pick playing - you can find it in just about any punk / metal band where the bass is belt level or below.
When you have a low slung bass (as Mike Dirnt definitely does) you can’t approach the fret board with classic technique.
You options are: hike up the strap to chest level and look like some kind of square (not acceptable)
or
Sling it low, and find a way to make it work.
The cool thing about the low slung bass and the fretting hand, if you’re playing with a pick, you can really go nuts with the picking hand. The different grip with the fretting hand frees up the thumb and makes it a very useful muting tool for the lower strings.
That way you can slam away with the pick and not have to worry about accuracy too much and still get out the note you need to get out.
I love playing like this. It’s an adapted technique for a very specific live appearance and attitude - it’s certainly bad technique (and hard on the back).
But it feels real good when you’re standing in front of a wall of speakers and the drummer is playing as hard as they possibly can.
(Chris Novoselic of Nirvana)
Thanks for the feedback everyone some interesting stuff. Maybe in a few years I’ll look as cool as Krist!!
Also - big high fives on the Architects reference. Such a killer band!!!
Great band! Have you heard their new song “Black Lungs” that came out today? It’s great I can’t wait for their new album!
Ludder,
I’ve been playing for a little bit and I not only mute the “E” with my thumb, when a note is required, depending on where on the neck I’m at, I’ll use the thumb of my fretting hand to press for the note.
After awhile, you will find that while there is a “Technically” correct way of playing the Bass, you will find that a particular way works best for you. Learn the right way, but, don’t be afraid to use your own style. If it works for you, go for it.
-Sam-
I’ve always use my fretting thumb to mute the E string whenever needed - have been for years since I started playing guitar sixty years ago and the technique just kinda held over to when I started playing bass 18 months ago. Even though I did take the B2B course and fretting thumb placement is discussed from the very start, I kinda look at it like when I started taking Drivers Ed in High School back in the 1960’s and the instructor always telling me to keep my hands on the steering wheel at the 10 and 2 o’clock position… I guess it’s a good thing that clocks were invented before steering wheels… Otherwise no one would know where to put their hands when driving…
Like the thumb on my fretting hand when playing my bass,… I can guarantee you that my hands have not always been at those aforementioned coordinates on the steering wheel of anything I’m driving these days… Besides, as long as my fretting thumb is located somewhere near to, or on a bass string, my wife can never make mention of it being stuck up myA$$ when it’s time to get up off the LazyBoy and take the trash out… 
Using the fretting hand thumb to mute the E string was one of those habits that persisted through my 45 year “break” from playing bass.
After discovering through various videos (Joshes and others) that this was considered a Bad Habit, I attempted to stop doing it. Easier said than done.
Then I saw this video:
If Sir Paul can mute with his thumb, so can I. 
I don’t do it much on bass but weirdly I have already found myself doing it on guitar 
Spidey,
Had never seen that. Thank you and as I said, “if it feels good to you and it works, do it.”