Rumble in LP and effect in speaker

[pratimbayal]

Dear Friends

I want to know about the effects of rumble noise in the speaker. After getting my new Micro Seiki TT, I am now listening LPs mostly. What I observed in case of some older LPs , the speaker driver vibrates quite a lot though gain is not much. This is a issue with old LPs mostly and nothing to do with the TT or Phono. With new LPs , specially with imported one this vibration is much less may be at par with that of playing a CD.

I believe that this is low frequency rumble , since not audible , that is more prominent with older LPs- I have some very old LPs where the vibration is much more. Though there is no issue with the quality of sound as such.

My query is whether this is a common issue ?
Whether there is any adverse effect on speaker driver for that extra vibration from that inaudible low frequency rumble?

Please share you experience

Regards

 

[Hiten]

Rumble frequency range on its own is very difficult to produce any vibrations on speakers. May be overtones of low rumble. But that too will be noticeable if speakers are capable of producing it. What you may be experiencing is noise generated by used vinyls. I may be wrong though.
Regards

 

[reignofchaos]

Seen that happen when the phono amp doesn't have proper rumble filters to cut off the low frequency rumble. Try with a different phono pre and see if the issue persists.

 

[reubensm]

Was looking up the definition of rumble on wikipedia and noticed that the first 2 paragraphs may be relevant to your observation.

http://en.wikipedia.org/wiki/Rumble_(noise)

On another note, I have noticed enhanced levels of surface noise on older LPs (which is audible). This is probably due to factors like wear on the records caused by constant play or mis-use by the previous owner (for pre-used LPs), especially if the record has been played with heavy-weight tracking. Some time ago, a friend gave me an LP which was played with a 78rpm sapphire stylus (by mistake) and it had an awful gushing noise which was particularly audible in between tracks or in silent areas/low volume areas of the tracks.

If tonearm and cart calibration is not done properly, again surface noise can increase, especially if antiskate is not calibrated properly. All this assuming your turntable is not producing audible rumble (since you're noticed this only while playing older records)

 

[Selvin]

This is by sub sonic frequency signals due to wrapped records. Just check visually the playing record is flat. This can be easily observed by watching tone arm when playing. Tone arm moves up down while playing wrapped records. This can be eliminated by using a Phono stage with subsonic filter. No need to worry much if the speaker cone movement / record wrap is small. It is better to avoid playing highly wrapped records without subsonic filter which may load the amplifier as well as not good for speaker.

 

[pratimbayal]

Yes what I am observing is from old LPS . There is an associated noise if the volume is raised up . But the vibration is much more. As ROC has mentioned about rumble filter - I also heared that earlier the amp/ phono preamp use to have rumble filter. Then we can assume that rumble can exists even in new LPs which were manufactured in earlier times.

Will that vibration have adverse effect in the speaker ?
An expert in Kolkata said speaker will not at all be damaged.

If we use a rumble filter , what is the sacrifice to the SQ ?


Regards

 

[pratimbayal]

Hi Reubensm

Thanks for the link. I can exclude the rumble for "turntable" - since nothing is there in relatively new records.

To me it is only due to " irregularities in LP "


Regards

 

[reubensm]

If we use a rumble filter , what is the sacrifice to the SQ ?

From experience (father had built rumble filters and played around with them in the past), rumble filters in their simplest form are essentially customized low pass filters. Yes, with the rumble some of the lower frequencies are swallowed (as noted by the human ear) but this may not be the case when these are tested and their effectiveness proven, in lab environments.

 

[pratimbayal]

Last night I again tested some of my LPs ( which sounds very good ) - and I have feeling now that the vibrations are not much to be worried.

Though eliminating them might improve things for better.

Thanks

 

[Thad E Ginathom]

rumble filters in their simplest form are essentially customized low pass filters.

Aren't they high-pass filters?

The terminology is confusing, because in most cases when we think of a filter we classify it by what it filters, ie removes, but here the classification is by what it allows through.

 

[IndianEars]

Yes, Thad is correct. A Rumble Filter is Usually a "High Pass" or a Low Cut filter.

The Rumble output is out of phase in the 2 channels. hence if your Amp has a Mono switch, put it on and Magic ! The Large Cone excursions will vanish ! ( No Rumble).

A direct implication : Good Rumble filters do NOT cut off the bass, they simply mix the bass of both channels ( Mono Bass). That leaves all the Bass intact but cancels the Rumble !

Bass frequencies are of very long wavelengths, hence essentially, there is almost no difference in the bass ( below 50 Hz where Rumble is prevalent) between the left and Right Channels. hence Mono Bass does not spoil the imaging.


Rumble will waste your Amplifier output power and if a low power amp is used, it could cause audible distortion, if a record with significant rumble or warped records are player loud....

 

[reubensm]

Aren't they high-pass filters?

The terminology is confusing, because in most cases when we think of a filter we classify it by what it filters, ie removes, but here the classification is by what it allows through.

Always thought it was the other way round. Went through the wikipedia definitions and it makes sense now

 

[Thad E Ginathom]

Always thought it was the other way round...

Me too. but...

Low Cut = High Pass; High Cut = Low Pass. I only got to grips with it since I've been playing with EQ on the PC audio and learning what the "knobs" do.

IndianEars, thanks for that technical rundown.

 

[Hiten]

I think rumble filters are thing of the past. Phono preamps on the contrary boosts the low fq. range (RIAA). Modern turntable are well engineered to have rumble noise very well below audible range. Also most of the speakers can not out put 20hz, unless one uses subwoofers. So in this case vinyls are most likely to cause this noise. Rumble noise inherent in recordings or manufacturing can not be removed.
Regards.

 

[pratimbayal]

Is there any good rumble filter in the market which will reduce the cone vibration with out loss is SQ ?


I was playing a new LP of Darr yesterday. The cone vibration is little extra ( though well with in comfortable lebel to my personal feeling) than a CD. So I assume rumble is inherent in a LP , though the degree varies .

Regards
Pratim

 

[mahiruha]

Hi Pratim ,
I have noticed this excessive cone vibration in my speakers as well with Nighthawk phono stage and ortofon 2m red combo in some cases. It looked a bit scary but the moment I switched over to using moving coil cartridges with nighthawk it doesn't happen anymore. I can't recall which particular record it was. Btw what cartridge you are using? It may well be the case that hgh gain of moving magnets are making this rumble effect more pronounced than it should be and nighthawk is missing something.
Thanks.

 

[pratimbayal]

I am using Ortofon 2M Bronze cart with Nighthwak phono

 

[Saket]

Could this rumble be due to the mono records played on a stereo cartridge? The dead channel putting up too much rumble? Is the cartridge wiring correct? if that's the case, hitting the mono switch on the amp should solve the problem.

 

[mahiruha]

I am using Ortofon 2M Bronze cart with Nighthwak phono

I see. In that case I would suggest if possible try a different TT cartridge combo with the same Phono if the problem still there then problem is with phono if not then this mm cart and phono combo perhaps not working. From my experience it is not normal.

Thanks.

 

[G401fan]

I was getting high cone excursions with my MC cartridge, but not with MM. Switching on the rumble filter in my phonostage removed the problem, with no loss of bass fidelity.