turntable rumble

[danger boy]

Why is the turntable rumble so bad on my Pioneer PL530? is there anything that can be done about it?

It became more apparent once I tweaked the tone arm to the proper tracking force and weight.. the sound is better overall, but it seems like it's picking up more rumble or motor noise.

[aaharvel]

good question - if anyone has an answer i could benefit as well.

[sucks2beme]

Very common problem with budget TT of the day.
That's why many 70's receivers had a low frequency filter.

[billbillw]

Check the bearing surfaces. Clean them really good with 90% isopropyl, re-lube with clean oil or grease. If that doesn't help, the only cure is to get a better turntable.

[madmax]

My old Pioneer sucked big time for feedback. The lightweight platter is the main culprit. Face it, the platter is so light it becomes a microphone when you set the needle on it.
madmax

[bikezappa]

A good test for a turnatble is to put the needle down on a non moving record and slowly turn up the volume to say 10:00 then lightly tap the TT base not the record. Try increasing the volume to see when you start to hear da thump and maybe feedback.

[hearingimpared]

Why is the turntable rumble so bad on my Pioneer PL530? is there anything that can be done about it?

It became more apparent once I tweaked the tone arm to the proper tracking force and weight.. the sound is better overall, but it seems like it's picking up more rumble or motor noise.

With or without the clamp engaged? Also is it direct drive?

[hearingimpared]

ONe more thing, MC or MM cartridge?

[hearingimpared]

You can dampen the underside of the platter with either sorbothans sheets or Dynamat. If you decide to use Dynamat make sure it is perfectly rounded before applying cause once applied it is a bear to get off. That will definitely deaden any motor rumble being served up through your platter. I still need answers to the questions above.

[danger boy]

MM needle, using the Clamp, and although it's vintage Pioneer from the 70's, the platter isn't that light in weight.. but it's basically yeah as someone described it.. a microphone. i can tap the table and hear the tap come thru the speakers.

How come I don't remember any of these types of problem from the 70's? I know I didn't have a TT anywhere near this quality when I was young in those days.. but if I am going to be able to hear this rumble nearly every time I play an album.... that's gonna suck.

[jm1]

What is your TT sitting on? The top of an audio stand??

I would try placing it on a table that is stable and solid to see if that reduces the noise. I have my TT on a solid oak end table mass loaded with records on a lower shelf.

[madmax]

How come I don't remember any of these types of problem from the 70's?

Well that depends... :D

If you can get the table out of a bass node you might get by. Try to determine a place by walking around the room with some bass heavy music where there is a null, a real lack of bass. Put your table there and see if the problem goes away or lessens.
madmax

[cmy330go]

Try putting your ear right up to the platter while it is running without a record. See if you can hear any traces of friction or noise from the bearings.

[hearingimpared]

MM needle, using the Clamp, and although it's vintage Pioneer from the 70's, the platter isn't that light in weight.. but it's basically yeah as someone described it.. a microphone. i can tap the table and hear the tap come thru the speakers.

How come I don't remember any of these types of problem from the 70's? I know I didn't have a TT anywhere near this quality when I was young in those days.. but if I am going to be able to hear this rumble nearly every time I play an album.... that's gonna suck.

Can you check or change your MM loading? When my load was too high with my MM Alchemist, it picked up every little thing. Also, if your table is direct drive which I believe it is, your motor is most likely the culprit. You may be able to dampen the motor.

Your rig in the 70s probably wasn't as hi-rez as what you have now.

[danger boy]

Joe, yes it is a direct drive unit. it is sitting on a heavy oak table.. so it's should not be getting any rumble from bass or anything like that. I agree it's probably the motor or something.

How do i find out the MM load? my friend just balanced the tonearm for me. to i believe 1.5g to 2.0g. as best as we could tell. we also removed the rear most weight on the arm.. that was giving us fits on proper force.

[unc2701]

Ok, do the thump test on the surface that the TT sits on. Also, can you get a thump by hitting your heel on the ground?

The cheapest effective isolation that I've had work: 3 sheets of plywood, 3 bb's, bluetack and something heavy (I used two 40 pound barbells). super glue the BB's to the bottom of plywood sheet one, put big weights on top, ply sheet two on top of that, 3 wads of blue tack on top of that, last sheet of ply on top of that, TT goes on top. Not much vibration can make it through the bb's into the high mass of the next layer, the bluetack sucks up a lot of the remaining vibration. Once you've isolated the room, see if you've still got that rumble.

WRT maxmax's post #12, keep in mind that bass nodes happen in 3 dimensions, so try this with your ear on the floor & your ear at the level of the TT.

[hearingimpared]

Joe, yes it is a direct drive unit. it is sitting on a heavy oak table.. so it's should not be getting any rumble from bass or anything like that. I agree it's probably the motor or something.

How do i find out the MM load? my friend just balanced the tonearm for me. to i believe 1.5g to 2.0g. as best as we could tell. we also removed the rear most weight on the arm.. that was giving us fits on proper force.

If your preamp had loading for your phono in, you should be able to find it in your user manual. Most preamps that have a phono stage have MC loading some have both MM and MC loading.

To balance your tonearm you need to back off of the weight until it floats parellel to your platter. From there you can start adding weight to make the VTF recommended by your cartridge manufacturer. I've found that the upper half of the recommended scale is what is a good starting point, e.g. if the manufacturer recommends a VTF of 1.5 to 2.0 gms then start at 1.76 gms. Continue up towards 2.0 one-tenth of a gram at a time until your music sounds like it SNAPS into focus. That will be the perfect VTF for that record and pretty much any other record of that thickness.

[danger boy]

no more turntable rumble.. it was the old Kenwood pre amp I was using.

[hearingimpared]

Glad to hear it Al. Hum and rumble are very annoying.