--7---77---7---7---77---7--7777

for this riff from Demons & Wizards - Heaven Denies... how would you guys play it?

7---77---7---7---77---7--7777
D---DU---D---D---DU---D-DUDU

notice how some parts I go down down then up... and this goes pretty fast, so i was wondering, would it be better if i go DUDU for everything? I can do it, but it seems harder to keep the rhythm of the song when using strict DUDU movements.

Do whatever feels COMFORTABLE. It doesn't matter what the tab says to do. If it isn't comfortable don't do it if you have a way that is...you guessed it: more comfortable. Everyone will tell you the same thing

oh yeah oops...whys this going to be shut down, its more of a question for general purposes as well, its not just for this song i have these troubles...the thing is that if i do it my way, when it gets faster, i start having trouble because of the double down strokes. So should I just do it alternate dudu?

Yea as previously stated just do whatever seems easiest for you.

Doing it with the double downstrokes is a better workout for you wrist, so doing it like that might be a bit harder, but you will improve.
Also, doing it with double downstrokes means your wrist has a more regular motion, so the skill is more transferable to other riffs - it's a similar argument to the 'one finger per fret rule' - it could be considered better technique to do D DU D D DUDU rather than alt picking the whole thing.

Definitely keep playing the riff the way you do, D-DUD-D-DUD-DUDU..makes more sense, and it's a hundred times easier to keep track of the count. I'm pretty positive that that's the way Mr. Shaffer plays it, as well.

Strict DUDU is important when doing string skipping with the notes all being the same value, and such, but not for rhythms like that.

If there's even a slightest rest between notes, that should be an indication to retake and pick down again.

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hmmm i see ... thanks for the help guys!

When the notes are all the same value (say, all 16th notes) and you're skipping strings, isn't it better to do whatever needs less wrist motion?
For ex, if you've just played a 5th fret G on your D string and want to play a 5th fret C on the G string, and to hit the G note you used a downstroke, shouldn't you use a downstoke on the C as well?

Like this I mean:
G---------5-
D---5-3-5---
----D-U-D-D-

I would think that this is better because you don't have to move your pick below the G string before hitting the C note (if you want a wrist workout, just play some tremolo, or play this but faster!). It also is using the same idea behind sweep picking so I would think that playing like this would make sweep picking seem more natural to you.
Also this means that you should have played, at the end of the day, pretty much as many downstrokes as you hit upstrokes (since if you upstroke the C and want to play the G next, then you'll upstroke it as well), and this should mean that you develop your upstrokes and downstrokes equally, so that, for instance, playing a triplet DUD will feel just as natural as playing it UDU, and it should sound the same too, since your D will be just as powerful as your U.

The reason I ask is because I don't really know which is better. I want to know your (and all the other guitar players here) opinion is since I don't really know how to use a pick. You see, I play bass with fingers, but I'd like to learn pick too .... just it will take me long to get good at it .... so far I actually find that sweep picking is easier than tremolo picking.

I don't like doing whatever 'feels more comfortable' because I think that for some techniques, there is such a thing as doing it the right way or the wrong way. Here's an example: When you first start playing guitar, it feels more comfortable to not fret with all four fingers, but I don't think anyone here would disagree with me when I say that that is the wrong technique.

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The slayer song of south of heaven

ghosts of war

at the end part of the song, there is a rhythm chug that goes

D-D-DUD repeated with the DUD being a very fast pickhand triplet.

It does get confusing after awhile too!

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