Subsonic Rumble Solutions

"I believe that all LP systems would benefit from 20z (subsonic filtering)"

If done right, I would tend to agree.

the kicking of the drum or the pluck of a base string can be felt as well as heard. my wife, who loves to say "i hear no diference" feels it as well. it is not a rumble but an extension of the sound. it is tight, well defined, inspiring and adds to the music. heard often in steely dan, van morrison and dire straits albums amongst others, it gives the feeling of being there. on a diferent point it is my understanding that sound under 20hz can not be heard by the naked human ear, but only felt. also with some changes to his tt the originator of this post claims to have solved his trouble. i do understand your point, just don't agree. i avoid placing anything between the source and speakers, other then the minimal required. i subscribe to the therory, less is more and try to seek it in my equipment(2 channel) set up. you seem to be more technical savy then i. notably i do not have agreat knowledge of 20hz-30khz, -3db or such, but i know what sounds good to me. i have a very mechanical type mind and see flaws in the physical makeup/desighn once i understand the workings such as in the tt in question. i do not wish to be argumenitive and insist i know all, i am certain i do not. it is just your solution goes against my listening belief that if something is off there is a reason and something is wrong in the chain and the repair is not by altering but to repair, adjust, get rid of or replace. i have a relitively large vinyl collection some are better recordings then other. it occurs to me that you probably have a sub, i do not know what your system consists of, i do not, and you are referring to sub rumble which i have heard caused by the sub trying to make sounds out side(above) it's capability. i do not use a sub because i do not like nor feel that they are true to the sound of the music, movies yes. they tend to over state or exagerate. but to each their own.

It depends on whether what's happening below 20hz is related more to the music or noise. Best to eliminate the noise first if possible.

I got some 180gm Acoustic Sound LP's for christmas. I have to say the subsonic pumping is almost gone with these. yes, there's still a little cone movement, but not like a regular flimsy record.

So the problem I'm having seems to be more record dependent than anything else, or I would have the same level or problem on all records, right? I still think it is a problem with the media and not isolation or airborne vibrations and stuff (because it happens when music is NOT playing also, in the lead in/out grooves).

In any case, it still sounds good and is not a huge issue. It's just my completest nature that I would want to remove it if I can do so easily.

Enjoy,
Bob

Hi Bob, I agree, I too have some lps that have lots of low freq abberations (rumble and high levels of 20hz and below noise) and others I play are "close to perfect", very little rumble but the 20hz and down "noise" is there no matter what. This is the first thing you should address, as it does give your amp fits and also, even if you do not hear it it is screwing up your speakers sound trying to reproduce it.

Yes, if it is your setup it would be there regardless of the LP. You said subsonic pumping is almost gone with these LPs, what I believe you meant to say or are heaing is rumble (above 20hz). Correct me if you disagree. It can always sound better:)

My thought is that one can live with the rumble especially if ones system is down a a few DBs in the lower freq, but a 20hz filter will be of benefit to any system.

Bob