woofer pumping


Today I tried to play some vinyl through my new setup (Dynaudio C1 speakers and VTL MB-450 amps/VTL 5.5 pre) and I noticed a large amount of woofer pumping (Whenever I listen through the CD player or Squeezebox the woofers barely move at decent listening volumes).

My turntable is a Technics SL1200, cartridge is AudioTechnica 440 MLa and the phono pre is a Cambridge Audio 640P. Nothing fancy but the woofer pumping is worrying me and I'd like to reduce it. It's currently sitting on an Ikea Expedit so it's not the best for isolating vibration since just tapping it immediately makes the woofer travel more.

I was thinking of getting a 4" maple platform from Mapleshade with the Isoblock footers. Any other suggestions?
jibbonacci

Showing 1 response by newbee

No one has mentioned that the probable cause of the woofer pumping is a mis-match between the cartridge and the arm. This will do it every time. It is a arm mass/cartridge compliance issue you should investigate.

There is nothing wrong with using a subsonic filter but it better to fix the underlying problem than to add a band aid, I think. The problem still exists, you are just masking it. Additive is usually subtractive in audio.

FWIW, just a thought.