Help Diagnosing Turntable/Speaker Vibration Issue

[Connor1a]

Hello all you dedicated sound technologists… I could really use a bit of your thinking on an issue I’m having with my turntable. Here’s what’s going on.

When I gently drop the needle of my Technics deck (SL-100C) on an album, I’m greeted by almost silence. However, it seems like the moment the least bit of vibration hits my deck (say a footfall on wood floors), I’m punished with a growing vibration from my speakers (Warfedale Lintons + SVS SB-1000 Pros) that starts below my hearing range (I almost feel it coming) and takes off until I need to either lift the needle or filter out sub 100hz frequencies (I’ll explain below).

My setup:

Technics —> (RCA In) Waxwing (Optical Out) —> (Optical In) WiiM Ultra (RCA Out) —> NCx500 monoblocks —> Speakers.

The vibration through my speakers occurs when the deck is both on and off as well as both plugged in and unplugged.

I believe the vibrations are in the 70hz to 100hz range because the Waxwing allows me to configure its Lo setting (Butterworth filter) to remove a range of low frequency signals. As I go from its default of 25hz up through 70hz the vibration remains unchanged. However, when I hit 70hz it seems to reduce somewhat and then disappear when I filter at 100hz.

Thinking it could be a tonearm dampening issue, I installed a liquid dampening paddle on the tonearm. It’s made no discernible difference.

My next tactic is going to be to wrap the tonearm in plumber’s tape (carbon fiber). I’ve read several posts that this may help reduce tonearm vibrations.

If that fails, my next todo would be to install a wall mounted shelf for the deck. Unfortunately, my room is quite small so my placement options are limited. The deck either needs to stay where it is, but on a shelf, or move to the other side of the room which would be … suboptimal.

A couple of other points. Both the speakers and the deck are on decoupling stands. I’ve attached a (messy) pic so that you can see what I mean about placement options.

I’m guessing that there is something going on that’s noob simple and I’m just not getting it. Some sort of acoustic feedback loop or some such. My worst case scenario is that the speakers are too close to the turntable as that would mean moving the deck across the room which is a nontrivial event (doable, but a pita). My acoustics are a challenge, but that’s a different saga.

Thanks in advance……… I sincerely appreciate your help.

 

[DSJR]

Maybe a change of cartridge? The Linn Axis/K9 combination could have the arm shivering up and down on the cartridge suspension quite ofyten irrespective of the speakers unless they were tiny.

Deck off - is that with stylus on the record or with arm back on its rest. if the latter, check for hum/ground loops which do all sorts of nasty things.

 

[markstein]

Hi,

I cannot imagine that it's your speakers too close to the turntable. I have a similar setup, no feedback issues at all, even if jumping on the floor.

Maybe your wooden floor resonates? In this case, a wall mounted platform would help.

I guess the tonearm is set up with correct weight and a cartridge with matching compliance.

In any case - I would not recommend wrapping your tonearm with any material to "reduce resonances".

 

[Laika2]

Wall mount, mine is right above a dual 15 inch sub, no issues after I wall mounted it. This Mark agrees with the Mark above.

 

[Connor1a]

Maybe a change of cartridge? The Linn Axis/K9 combination could have the arm shivering up and down on the cartridge suspension quite ofyten irrespective of the speakers unless they were tiny.

Deck off - is that with stylus on the record or with arm back on its rest. if the latter, check for hum/ground loops which do all sorts of nasty things.

Pretty sure thats a screen capture of a video with the deck spinning.

Did try another cartridge. I should have said that. I tried two AT-VM carts. I have the SH and ML. Same from both. One on a Technics headshell. The other on an AT headshell.

 

[Connor1a]

Hi,

I cannot imagine that it's your speakers too close to the turntable. I have a similar setup, no feedback issues at all, even if jumping on the floor.

View attachment 457351

Maybe your wooden floor resonates? In this case, a wall mounted platform would help.

I guess the tonearm is set up with correct weight and a cartridge with matching compliance.

In any case - I would not recommend wrapping your tonearm with any material to "reduce resonances".

Further problem solving…. It has something to do with my right sub. I turn it off and cannot recreate (yet) the resonance issue. I started poking around in the subs’ PEQs (from when I set them up in December). It just “feels” like a sub issue as it’s between 70hz and 100hz. I finally just tried switching them off and the problem stopped. Toggled back and forth a few times and it has something to do with my right sub. I dont think the sub is bad, I think its either a bad config or its in a bad location.I may spend tomorrow moving furniture….. Thank you for the thinking.

 

[markstein]

Maybe you could also try another decoupling between sub and floor which may change the way your floor panel start resonating. Good luck!

 

[RayDunzl]

I'd try moving the turntable to the other end of the "rack", just to see...

 

[DVDdoug]

I also think a shelf attached to the wall might help.

Maybe you need some kind of isolation base under the turntable (unless that's already what your turntable is sitting on). You can buy them or rig-up something with springs. (I suspect that foam would be too stiff and the vibrations will pass through it.)

Or a heavy piece of wood as an additional bass would change the resonant frequency without any springs.

...some turntables are better isolated than others, so a different turntable would likely be better or worse. The 1st "real turntable" I owned was an AR and it was "bouncy" when you touched it but it had a reputation of being very well isolated from motor vibrations or external vibrations. The opposite "feel" compared to a "solid" direct drive turntable.

It has something to do with my right sub.

The feedback is probably from the sub(s) but radiated as sound into the room, and then through the floor. Speakers themselves don't usually vibrate that much but you can sometimes get turntable feedback if you put the turntable on top of the speaker.

 

[DSJR]

You also have coils of speaker? wire each side. Do you need that much, or could it be trimmed to a more suitable length?

Can the subs be tuned to roll out lower? I'm trading gently on eggshells here, but so many subs I've seen tested, admittedly a few years back, had far too much output at 80 to 100Hz even is set to roll off well below this. Do please remember that commercial vinyl records have little to no music at all cut into the grooves below 40Hz in any case and I'd have thought the Wharfedales would go down perfectly low enough on their own with vinyl as a source. Others here use DSP and so on, but in the bad old days before proper active or semi-active sub crossovers into the mains, I always believed that if a sub can be *heard,* it's set too high and for music use, it may be best to just set it/them to gently underpin what the speakers are doing.

Extra sorbothane 'boots' under the turntable feet may help a little too. The deck placed in the middle of the rack might possibly help. Maybe a heavy paving-style slab under the deck perhaps?

Just a few more thoughts which may or may not be suitable these days. Apologies for the scattering of ideas, but this is from a great distance here.

 

[1066]

This sounds like classic vibration feedback howl due to unsprung turntable suspension design.

Cabinets, sideboards and wooden floors will transmit vibration and resonate at the low frequencies the subwoofer produces.

I would turn the subwoofers off for vinyl. There’s so much low frequency distortion on vinyl.

If the wall is brick, use a dedicated turntable wall shelf. Light and rigid. No bigger than the turntable.

Do not allow the turntable signal cable to touch the wall or any other resonating surface.

Have experienced this with certain turntables in past.

 

[antcollinet]

This sounds like classic vibration feedback howl due to unsprung turntable suspension design.

Cabinets, sideboards and wooden floors will transmit vibration and resonate at the low frequencies the subwoofer produces.

I would turn the subwoofers off for vinyl. There’s so much low frequency distortion on vinyl.

If the wall is brick, use a dedicated turntable wall shelf. Light and rigid. No bigger than the turntable.

Do not allow the turntable signal cable to touch the wall or any other resonating surface.

Have experienced this with certain turntables in past.

This - At one time I had my turntable on a pine chest of drawers next to the speaker. The chest acted as a soundbox/soundboard, and resonated at a particular frequency creating feedback via the turntable.

I fixed this by putting a heavy oak board (actually half of a solid oak door) on top of the chest, with damping material between the chest and the oak, and between the oak, and the turntable.

You've obviously got something similar going on between your right sub and the turntable.

You could try to damp it - or depending on your room, you could move the turntable away from the speakers. I have my turntable now at the opposite end of the room from the speakers. An advantage of the waxwing is you can use the digital output with a long toslink cable to connect it to your system - with zero noise issues.

 

[1066]

I do recall having a Rega Planar 3. It suffered terribly from vibration through its feet and a bass note in music would set off an increasing howl. I had to put the hifi outside my room and run speaker cables under the door

 

[1066]

You can try Sorbothane hemispheres, I believe sorbothane is an American company, not sure where you are based. The size of the hemisphere needs match weight of the turntable.

Rubber based isolation does not work so well as it’s so bouncy.

 

[DSJR]

I do recall having a Rega Planar 3. It suffered terribly from vibration through its feet and a bass note in music would set off an increasing howl. I had to put the hifi outside my room and run speaker cables under the door

The early Regas with R200 arms were terrible for feedback, but a properly tightened post '83 sample with RB arm was very much better in this regard. Mind you, even today, a Rega prefers being used sans lid and the deck on their wall-bracket on a solid wall away from corners (bass does 'sound' different with siting changes I remember).

Thanks to Linn and others, we 'flat earthers' in the UK developed ways and means of supposedly 'improving' the sound from records and isolation was a huge part of this in the days before digital began to make huge inroads into the main audiophile market.

 

[1066]

The next turntable I got was a Linn which had the full sprung suspension. It was far less susceptible to external vibration and never produced howling feedback.

When a record is playing and you close the lid, if you can hear the lid closing through the speakers with ‘bong’ you know the isolation is bad.

I hope the original postee has a brick wall to mount a small shelf onto.

If it is gyproc and wood stud work there will still be some vibration from wall.

 

[1066]

The early Regas with R200 arms were terrible for feedback, but a properly tightened post '83 sample with RB arm was very much better in this regard. Mind you, even today, a Rewga prefers being used sans lid and the deck on their wall-bracket on a solid wall away from corners (bass does 'sound' different with siting changes I remember).

Thanks to Linn and others, we 'flat earthers' in the UK developed ways and means of supposedly 'improving' the sound from records and isolation was a huge part of this in the days before digital began to make huge inroads into the main audiophile market.

Ah yes I just looked up rega R200. That WAS the turntable version I had howl-around from. The removable head shell was not horizontal either.

 

[1066]

Project still make a turntable shelf.

 

[DSJR]

These things sell for loads-a-money these days - the original Rega one was simple, basic with three 'cups' welded on for the feet to slip into and very cheap (it ain't now in current form, sadly) and was easily converted to have a board on top to take a conventional deck!

One trick if a cupboard or chest was used to put the deck on, was to use a separate light but rigid board (balsa was ideal, but at the time we used a variety of available materials around 5 - 10mm thick, sitting on upturned spikes, ball bearings, sorbothane feet or whatever. Different uses for different occasions and turntables, but this could work.

My main gear sits in a heavy (veneered MDF) cabinet/cupboard which sits firmly on the floor, crushing the carpet where it's sited. I've tried a variety of decks on the top of it and I can pound the top of the cabinet while a record is playing and nothing gets through at all. It's so massive I dare say that a wood floor wouldn't be much if any worse here.

 

[1066]

These things sell for loads-a-money these days

Yes I just looked, would be cheaper to get a welder to make one for the money they are charging for turntable shelves!

Maybe on eBay there may be one.