Speaker cones oscillating violently when playing vinyl

[admin_exported]

I wonder if anyone can help me with this particular problem. I have a Michell Mycro turntable - when I play vinyl I find that the cones of the speakers oscillate fairly violently backwards and forwards. This doesn't happen with CD or any other input. I have stopped playing vinyl because of it, plus there's a low level hum going on. The speakers are ProAc Studio 100s and I have John Shearne amplification.

Any thoughts?

Thanks,

Benny

 

[Clare Newsome]

Vinyl playback can shift serious air compared to same track on CD: perfectly normal with dynamic/bassy excerpts. Hum could be due to turntable needing to earthed better (could be down to poor cable shielding).

 

[MajorFubar]

Do you mean during parts which are supposed to be silent? This can be caused by any number of things, such as rumble from worn main bearings, feedback from your speakers to your cartridge or vibrations from the floor to the turntable, or just simply noisy vinyl.

 

[Andrew Everard]

...Or even relatively mild warping of the record being played.

 

[Anonymous]

Thanks everyone. I've moved the turntable to a different position, and on the particular album I'm playing (The Zawinul Syndicate - Black Water) there is little or no background noise and the cones are less violent in their movement. Seems to be working just grand. Thanks all for the comments and help.

Benny

 

[MajorFubar]

No worries Benny this site's all about bouncing ideas off each other. Glad it worked. After relocating your TT you may also find the bass is also bit snappier and tighter now, considering the problems you described before.

 

[Henley]

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The cone flapping is due to a subsonic noise caused by the warp in your records. Many amplifers (or phono stages) have a warp filter to eliminate frequencies below around 18Hz, it would appear that yours does not have this facility. Although unsightly, it is not harming your speakers and many audiophiles prefer not to use any filtering as they believe is degrades the sound quality.

 

[Anonymous]

I am guessing that you have a 'bouncy' suspended timber floor in your room, your speakers/stands are spiked to the floor and your turntable is also on a rack/table resting on said floor.

Best way to solve this would be a wall mounted turntable shelf:

 

[Andrew Everard]

... Although a turntable wall-shelf is a good idea in isolation terms, not sure how it cures warps in records.

 

[Anonymous]

I wonder if anyone can help me with this particular problem. I have a Michell Mycro turntable - when I play vinyl I find that the cones of the speakers oscillate fairly violently backwards and forwards. This doesn't happen with CD or any other input. I have stopped playing vinyl because of it, plus there's a low level hum going on. The speakers are ProAc Studio 100s and I have John Shearne amplification.

Any thoughts?

Thanks,

Benny

Thanks everyone. I've moved the turntable to a different position, and on the particular album I'm playing (The Zawinul Syndicate - Black Water) there is little or no background noise and the cones are less violent in their movement. Seems to be working just grand. Thanks all for the comments and help.

Benny

... Although a turntable wall-shelf is a good idea in isolation terms, not sure how it cures warps in records.

Andrew, where did Benny mention a warped record? In his second post he states that a turntable location change improved the issue he was having, leading to my post suggesting a wall mount to isolate.

 

[Andrew Everard]

Andrew, where did Benny mention a warped record? In his second post he states that a turntable location change improved the issue he was having, leading to my post suggesting a wall mount to isolate.

Both Henley and I pointed to warps as the cause of the problem. The change of location may have reduced the amount of acoustic feedback between speakers and cartridge, but the cause remains those warps.

 

[Anonymous]

A lot of modern phono stages have a very extended low frequency response, well below 10Hz. When you play a slightly warped record it amplifies this ultra low frequency motion of the stylus and you get cone flap. Filters have been used in the past but this takes away bass punch, so this is the compromise. As for the hum-is the phono stage inside the amp or separate stand alone unit ? Is the record player above the amp in a stand ? It might be hum pickup from the mains transformer in your amp or the arm earth is not good. Does the hum vary with tonearm position ? The cartridge may be picking up from the motor.

 

[hybridauth_Facebook_1098944303454514]

I have a (temporary) Panasonic Turntable thats into the Pro-ject Tube box S into a Camridge Audio 651a powering a pair of Monitor audio bronze BX2's.

Same issue Benny has. Speaker cones go back and forth like mad men! Kinda worried I may damage something!

If I go back to MP3 mode via the Cambridge on board DAC then the speakers can be turned WAY UP with no flap!!!! Tight and punchy!!!

I bought the Pro-ject tube box S thinking that may filter out something that caused the speakers to push that much air. I've set the Tube Box up via the dip switches (as per the instructions) but still the speakers go nuts.

I would be very grateful for any advice!

Thanks!

David.

 

[CnoEvil]

I have a (temporary) Panasonic Turntable thats into the Pro-ject Tube box S into a Camridge Audio 651a powering a pair of Monitor audio bronze BX2's.

Same issue Benny has. Speaker cones go back and forth like mad men! Kinda worried I may damage something!

If I go back to MP3 mode via the Cambridge on board DAC then the speakers can be turned WAY UP with no flap!!!! Tight and punchy!!!

I bought the Pro-ject tube box S thinking that may filter out something that caused the speakers to push that much air. I've set the Tube Box up via the dip switches (as per the instructions) but still the speakers go nuts.

I would be very grateful for any advice!

Thanks!

David.

You are suffering from the very low frequencies that vinyl (especially if it's warped), can cause. One option is to use sealed speakers, which help offset this, due to their different loading.

 

[TrevC]

It can be exaggerated if a high mass arm is used with a high compliance cartridge which sets up a resonance, but is a characteristic of vinyl. Another shortcoming to add to the long list. Warping is not the problem despite what was said above.

 

[CnoEvil]

Warping is not the problem despite what was said above.

Are you sure?

Wikipedia has this to say about Rumble, of which I thought warped records was one source (along with TT/Arm/Cart design):

"...but even with the best turntables a lot of rumble tends to be generated by warped records or pressing irregularities sometimes visible as ‘bobbles’ in the surface."

I suppose it depends if the problem is across all albums....if it is, you are probably correct.

 

[MajorFubar]

Records have rumble. It's intrinsic to the playback process and is exacerbated by RIAA EQ, warps and thin, cheap recycled vinyl. Why do you think in the dark old days before they invented a true HiFi music carrier in 1983 most amps used to have high-pass filters called rumble filters that lopped-away the bass.

 

[TrevC]

Warping is not the problem despite what was said above.

Are you sure?

Wikipedia has this to say about Rumble, of which I thought warped records was one source (along with TT/Arm/Cart design):

"...but even with the best turntables a lot of rumble tends to be generated by warped records or pressing irregularities sometimes visible as ‘bobbles’ in the surface."

I suppose it depends if the problem is across all albums....if it is, you are probably correct.

Think about the frequency that would be generated by a warp. The cone would move very slowly in and out at around 2Hz if a warp was the problem, and most phono stages would roll that off. If it was severe and steep enough to make any kind of noise it would probably chuck the stylus out of the groove.