sooo ive been really trying to get the speed of my downpicking faster bu to no avail(i play alot of thrash ie MD metllica Pantera etc) for instance when pedaling on the low E with downstrokes i cant always keep up tempo but recently my pedaling using alt picking on the low E has allowed me to keep up- does it matter which way i choose to play?? i know guys like Hammett recorded the songs i love with all downpicking(which blows my mind)....it just seems so ipossible for me to ever get t that speed. anyways if anyoen has thoughts or ways to improve my speed please let me know..and dont say PRACTICE because i do..alot..
The only way to increase speed is to practice playing accurately (a metronome will help), and slowly increase the speed you practice at. Speed is a by product of good technique, accuracy, and practice.
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I use to do an exercise where i would play entirely with downpicking and then play for a while with all upstrokes. Makes your alt picking very fast after a few weeks. Just keep practicing, a metronome would help.
Down picking gives a more aggressive sound, which is great in metal rhythm guitar.

To get it fast, make sure the wrist is relaxed, and that its the wrist creating the picking motion. Try keep the option small and accent (pick harder) on the beat.

I think I actually do some thing slightly different with my wrist when down picking constantly, ala Hetfield, than I do when alternate picking. But its hard to explain with out us being in the same room.
If it sounds good, do it.

Yes, downpicking can achieve a distinct sound, but it has its limitations. So many people get caught up in the mentality that they must downpick fast like Metallica. Well, I hate to break it to you, but their downpicked rhythms are no longer considered fast - though their riffs were quite fast for downpicking.

What I'm saying is, you'll be able to build much faster riffs if you alternate pick. And even Metallica used alternate picking on faster sections of songs - like a lot of the riffs at the end of "One."

I read a quote from James Hetfield one time where he said "Yeah, I downpicked ALL of One." (He was joking of course - but he said it was funny to see the expressions on people's faces.) The point is, even Hetfield admits that you can only go so fast with all downpicking.
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If you can get your upstrokes as consistent as your downstrokes, it doesn't matter which way you play it.
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