Does anyone use a RUMBLE filter?

I suspect the RIAA filter is good?? With a rumble filter, I suspect, there is no phase shift because you are cutting out subsonic frequencies, not crossing over to them on a different driver.

Rauliruegas
Dear Actusreus: probably you don't know how filters works so take a look on internet to learn about other that what Onhwy61 posted.

This is your response? I thought you knew what you were talking about. Sounds like you're simply repeating your analog rhetoric without much scientific knowledge on the subject to back it up. Sorry, but that's not very convincing to me.

It seems to me that the audio signal is always necessarily "filtered" once that stylus and its motor assembly picks it up off the record surface. Open up your phono, line, and power amps and you'll see all sorts of "filters" such as transformers, resistors, capacitors, chokes, etc. I don't doubt that there are better and worse subsonic filter designs out there, just as there are better and worse amplifier designs out there, and I do understand the argument that fewer components in the signal path is more desirable. But after reading countless posts about rumble filters on this forum over the past several years, I still have not seen a convincing argument how a well-executed rumble filter degrades sound except for purist rhetoric. Onhwy61's post is a good start, but I'd like to see more informed responses.

The most popular rumble filter on the market is the KAB filter. It's supposed to be transparent and not affect the signal except for the undesirable ultrasonic frequencies it is designed to filter. I'd like to hear an educated opinion just how this filter degrades the audio signal besides adding another pair of IC to the path.

Dear Dinster: No, RIAA " filter " is not good and damages the audio signal.

In the other side a subsonic filter is not transparent because needs passive or active parts to function and the signal has to pass trough. Now, if the preamp design has it as an option then only damages when is swtiched on and when off ( if was designed that way. ) is out of the audio signal: the signal does no0t pass throught it ( insist, if was designed that way. ).

What I can't understand is why the posts of you are around the rumble filter instead to fix by origine the system woofer movements/pumping. IMHO, makes no sense.

Regards and enjoy the music,
R.

I have a carefully and properly set up turntable that sounds great, and the only difference between the phono preamp filter being on or off is that when it's on the woofers don't pump with subsonic crap and my tube amp's bias lights don't indicate wild voltage fluctuations. Absolutely zero signal degradation. Prior to this preamp I used a preamp with a built in phono stage and had to use line filters (Nakamichi...amazing little items no longer available) that also showed zero signal degradation. The fix is in!

Rauliruegas, please explain your comment that the RIAA filter is no good and damages the signal. Are you referring to the IEC update to the standard RIAA playback curve?