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RyKnocks
08-13-2011, 11:14 AM
How do stiffness and vibration/feedback correlate with each other? My MG Radical MP has a lower flex rating than my Pure Storm Tour GT but it doesn't vibrate nearly as much on hits (if at all) as my PSTGT.

So because it doesn't vibrate as much, does that mean it has a "stiffer feel" or am I experiencing a more "solid feel?" I still feel the plushness of the MG Rad and it's definitely more comfortable to hit with. Just wondering how stiffness and vibration are related.

On a side note, I've been looking at the Volkl PB10 Mid and it looks like the perfect balance between my MG Rad and PSTGT. Can anyone comment on this racquet compared to the ones I already own in terms of feel?

Thanks!

corners
08-13-2011, 09:13 PM
Stiffness correlates with vibration frequency, which you can also call dynamic stiffness.

Generally, lower RDC stiffness numbers mean lower vibration frequency and less shock.

Higher RDC stiffness numbers mean higher vibration frequency and more shock.

Stiffer racquets actually vibrate "less", as higher vibration frequency mean lower vibration amplitude. The entire frame is bending back and forth as it vibrates - lower amplitude means it's bending back and forth a shorter distance each time.

Players who have problems with shock - due to tennis elbow or whatever - tend to like flexy frames.

Other players don't like how flexy frames vibrate with high amplitude. If you've ever hit with a wood racquet you'll know how this feels. The tip oscillates back and forth with a strong "fluttering" vibration. Wood racquets are very flexible so they don't transmit much shock, but they also vibrate like crazy because of that flexibility.

Otherwise it's a matter of feel. Manufacturers do stuff to the layup and handle to reduce vibration. They seem to be getting better at it.

You can compare various frames on the market objectively using the data on this table. Choose sort by "vibration frequency".

http://twu.tennis-warehouse.com/cgi-bin/vibfrequency.cgi

fuzz nation
08-14-2011, 05:47 PM
I'd actually say that you're describing a softer feel in the Radical as far as it not vibrating so much. A stiffer racquet typically transmits more vibration upon impact into my hand while a softer frame will "soak up" some of that rattling. If you ever get to hit with a ridiculously soft racquet, it may seem like you're hitting the ball with a hunk of jello on a stick or even a pillow. Zero vibration.

While that may seem to lend a degree of solidness to the general feel of your racquet, it's likely that you'll get a stronger impression of that with a significantly heavier frame. It's sometimes referred to around here as "plow through" where the racquet goes through the ball with greater inertia. When that's the case, the ball seems much less likely to push the racquet around, even when hits are a little off-center.

The harshest feeling racquets of all for me - with the most vibration - are the ones that are both rather light and also quite stiff. Even catching the ball on the sweet-spot with that layout can be accompanied with significant vibration.

Power Player
08-14-2011, 07:10 PM
I have a stiff racquet but it gets no vibration...so it feels incredible. Probably the best of both worlds IMO.