Playing Loud

HELLO i once had a piano teacher that said -whenever playing loude chords or octaves there is a need to contract the muscles of the hand a bit in order for it to be able to handle the weight or the velocity of the playing whenever playing loud,and also concentrate on contracting the hand muscles and not the forearm muscles-it doesnt make sense to me... I never quite understood why is that and if it is the right thinking when approaching playing loud chords ot octaves? thank you

It goes back to your hand structure and the arch. No need to put any excess force on the forearm if your hand is standing properly with the help of the thumb and MCPJ. There is some healthy tension involved but it's only function is to support the arch.

The muscle contractions in the hand, which are very necessary, need the crucial support of muscle contractions NOT in the forearm but in the upper arm. You are looking in the wrong place. The action of the biceps and triceps is HUGE and completely necessary to help the hand activate well. It is the lack of healthy activity in these two places that leads to tension everywhere else. AFF

true-but if im lifting the entire arm up and down towards the keys there is greater mass that falls down,and thus the sound will be louder. if the arm mass is bigger than just the hand mass,thus the tone will be louder,so the lifting of the arm is necessary. it is contradicting what is written in the book-for ff octaves the initial staring point is from the keys,and not lifting the arm. am i looking at it the wrong way?

true-but if im lifting the entire arm up and down towards the keys there is greater mass that falls down,and thus the sound will be louder. if the arm mass is bigger than just the hand mass,thus the tone will be louder,so the lifting of the arm is necessary. it is contradicting what is written in the book-for ff octaves the initial staring point is from the keys,and not lifting the arm. am i looking at it the wrong way? Mass does not make volume. Key speed makes volume. The larger arm mass will not make it any louder. This is a misconception. You lift the hand from the key, you just lose control of the key. If you need to to it for staccatissimo fortissimo octaves, it is still the FINGERS that make the octave, not the arm. The arm just helps, it does not take over. AFF

"Mass does not make volume. Key speed makes volume. The larger arm mass will not make it any louder. This is a misconception. You lift the hand from the key, you just lose control of the key. If you need to to it for staccatissimo fortissimo octaves, it is still the FINGERS that make the octave, not the arm. The arm just helps, it does not take over". but if im trying to play with just the finger,then playing from the wrist,and then lifting and lowering the entire hand ,the sound does get bigger and louder, isnt that prove that the mass does effects the volume?

No. It proves that the action of the wrist and the arm affect the volume. These actions are generated by muscular effort. Also the degree of structural connection affects the volume. The greater the key speed, the less you can afford to have shearing, structural inconsistencies. The more the entire arm skeleton needs to line up, not just the hand skeleton. AFF

so was i correct with lifting of the arm to get more sound? could it be the combination of lifting the arm and the fingers action which can create a bigger sound than just the fingers?

Lifting the arm will only give you a more banging sound. There is no use in it. Activate your fingers, activate your hand from the inside. Get capable. Don't rely on your arm to do it for you. Lifting your arm is like thinking you run with your torso. It's your legs that run, if you hadn't noticed... AFF