Well i think this easy kinds of tapping are pretty useless, beacause you can always play the tapped note on a higher string as well.
For example instead of playing:

-12(t)-8-5-0-

you can as well play

-7-------
---8-5-0-

Of course this doesnt work if you play
-12(t)-8-5-0- on the high e-String.

But usually you don´t need these tappings. I really think that nobody will hear a difference when you play the normal picking technic.
I don´t even think that you are faster when you tap this lick !

But tappings can be really cool though when you play triplets.
The best example is the solo from Metallica - One at 5:44
I think everybody knows it:

-20t15p12-20t15p12-20t15p12-20t15p12-
and so on...

Tappings can also be very cool when you mix them with some hammer-on and pull-off effects.

Mr. Blackfire is playing a very cool lick on the guitar solo (no other instruments) on the Sodom - Mortal way of live Cd

It goes like this:

----------------------------------------------------------
----------------------------------------------------------
-11t5h7p5-11t5h7p5-9t5h7p5-9t5h7p5-11t5h7p5-11t5h7p5-
----------------------------------------------------------
----------------------------------------------------------
----------------------------------------------------------

----------------------------------------------------------
----------------------------------------------------------
-12t5h7p5-12t5h7p5--------------------------------------
----------------------------------------------------------
----------------------------------------------------------
----------------------------------------------------------

This is a very cool one because it´s not very hard and even played slowly it sounds good!

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Of course you can tell the difference! It's like comparing the sound of a hammer-on with the sound of two individually picked notes. They are two distinct types of sound - the hammer-on is a 'slur' whereas the picked notes are more abrupt.

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Yeah, plus you look cooler when you tap.

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Well, i didn´t say that Tappings are useless! But in some Cases they are useless. For example in this lick i isn´t usefull (-12(t)-8-5-0-). Think of it in a realistic way! And i don´t mind if i look cooler if it tap it. I don´t play guitar to impress people!

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Learn That song
"The Philosopher" by Death,

listen carefully and practice man, thats easy...


Keep In Brutal...

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Listen to No Boundaries by Michael Angelo. Listen for the tapping arpeggios near the end. THAT IS WHY WE TAP

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One good use about tapping is the large interval leaps that you can accomplish fairly easily because your using two hands. It's fairly easy to recognize a tapping part in a song because of the jumps in the pitch.

Like tapping the 12 on high E and pulling the open e. Ex. t12p0
Stick some left handed legatos (hammers and pulloffs) in there, allowing you to blaze through an octave quite rapidly.

For multiple string tapping, I've been trying to barre the lowest common fret with my index and using the rest of my fingers to do the work. Requires a good stretch at times and also the ability to mute unwanted string vibration. Tough stuff.

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