HELP-woofer moves alot when playing lps

Transaudio, let me explain. IME, when you put any filter in the stream you can hear the effects. Well, at least I can in my system. Woofer pumping, which we cannot hear, does cause issues in higher ranges that we can hear as distortion and or nulls. I guess the easiest way to say is that we don't hear the direct effects around 20Hz but we can hear the side effects. Stop that woofer from flapping in the breeze and the bass tightens, etc. Add some filters and you also crush dynamics. Get the right filter and you get the best of both but you still give up something. Pick the compromise that works best in the system.

In my case I use a Marchand crossover and the natural roll off of my bass horns. The Marchand keeps everything below 100Hz confined to the bass horn which rolls off very quickly below 25Hz. Kind of a built-in filter.

As it happens, the Clearaudio Concept MM I purchased-broke. The needle was slowly moving to one side of the cartridge, and now is totally limp. I am going to return it as it seems to have a manufacturing defect. I purchased the Orotfon 2M Blue, which will arrive soon. Hopefully once it is installed I will not experience woofer pumping.

Thanks again for the responses.

Hi Dan_ed, I have a Triplanar too :) -and no, I'm not saying that. If set up right it handles the widest range of cartridges of any arm I've seen.

For more on this, take a look here:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1315713166&openflup&10&4#10

So when Atma-sphere amps show up not working one should assume they weren't built or serviced properly?

Dan_ed, At the very least, yes, though I don't understand what you are getting at at all. I feel like you are misunderstanding something though as there appears to be animosity on your part.

So maybe I have not been clear enough:

Woofer pumping is not a symptom of a speaker unless you are driving a small speaker well outside of it bandwidth limitations. IOW if the problem shows up on phono and not CD, its a problem with the phono and not the speaker.

Woofer pumping is a symptom of an incorrect cartridge setup, wherein the cartridge compliance combined with the effective mass of the arm causes the combination to have a mechanical resonance outside the range of about 7-12Hz.

Generally I would make it out to be too much effective mass coupled with too much compliance in the cartridge. IOW the cartridge's cantilever is moving a lot and the arm mass is not keeping up with it.

Fortunately with the Triplanar its easy to try the various and different weight setups until you find out what seems to work best with your cartridge.

So in this case to reduce the effective mass, you would put a heavier weight closer in towards the bearings of the arm and set it up for the same tracking weight. This will give the cantilever more leverage to move the counterbalance weight and so reduce deflection of the cantilever. This in turn reduces woofer pumping.

Does that make more sense??