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Where do classical vinyl records get their rumble from?

Recently converted back to vinyl from silver disks, I am struck by how much rumble seems to be inherent in the new and used vinyl I am buying.

A case in point, is a recent Deutsche Grammophon (DG) recording (487 7484) of Mahler’s Second Symphony made at a live performance at the Sydney Opera House (I was there).  The first set I bought was amongst the dirtiest pressings I have ever had, but the second set was much improved.  However, there is a persistent rumble whether played on my Holbo Mk2 air bearing system or my venerable Garrard 301 (new bearing from Classic Turntable Company).

Mahler typically has huge dynamic range, from muted off-stage performers to hundreds of musicians going hell-for-leather.

The rumble could be partly caused by the venue’s air conditioning system, but I hear similar background on a Telarc recording (Stereo 10051) of Saint Saens Organ Symphony made in Philadelphia.  Telarc even arranged to have local roads shut down for the recording sessions.

Similar efforts were made by DG when recording the organ at Notre Dame in Paris, where recording was done late at night to reduce traffic noise.  My copy includes Dolby Atmos on Pure-Audio Bly-ray (DG 486 1466).

I was beginning to think the rumble was inherent in my tables, but then I played a German Direct Metal Mastered (DMM) set from In-Akustik for Clearaudio’s 40th anniversary (INAK 78051 2LP).  It includes some Telarc tracks.  This set has the quietest background I’ve never heard.  There is virtually no rumble, exonerating my tables.

So apart from the recoding venue’s air conditioning and traffic noise, why do so many classical records seem to have built-in rumble?  Could it be from the mastering lathe?

I am really only thinking about classical recordings where the dynamic range approximates the signal to noise ratio of vinyl, meaning that very low-level signals are musically important, while simultaneously bumping against the noise floor.

richardbrand
kennyc
2,834 posts
 

@dwette - I was thinking of putting my Avenger TT on top of my RXR rack. Maybe that’s enough. VPI Avenger Pneumatic footers are 3.5k Yow!

dwette
530 posts
 

My HRS M3X2 isolation base retails for about $4300. I got a bit of a discount, but for the investment in my TT it has been well worth it.

I'm looking at six 10" active drivers on my REL subs, plus four 6.5" drivers on my two loudspeakers, and I never hear issues with rumble, bass distortion, woofer pumping or anything, no matter what I throw at them with my vinyl collection...other than with the the 2 problem records out of my 5000 LP collection.

richardbrand's avatar
richardbrand OP
1,362 posts
 

@audphile1 

 is this the Mahler 7 recording you referenced earlier in this thread?

Yes, that's it!

By the way, I contacted The Funk Firm to order more stick down tabs for their Achromat rigid platter mats, which are made from acrylic with lots of microscopic bubbles to absorb vibrations. I had forgotten that they claim to have treated the acrylic to prevent static.

They have stopped producing the 5-mm version in favour of 3-mm which fits Rega tables.

But they also have a 7-mm version which comprises a flat glass mat bonded to an Achromat with visco-elastic damping.  So I think they have achieved a high standard of 'flatness'.  The aim is to prevent stylus-generated vibrations from reentering the stylus.

richardbrand's avatar
richardbrand OP
1,362 posts
 

@kennyc

Seems that not all vibration mitigation devices work well with the internal micro vibrations of electronic components

Thanks for being more specific on the use of sorbothane.

I do not have a view on the sonic effects of vibration on solid state electronics.  I would not use native sorbothane on dynamic speakers either, because the cabinets should not move fore and aft.

Before I got my Holbo, I asked Bostjan what he stood his on and the answer was a 20-kg slab of MDF sitting on four sorbothane ’legs’.  In other words, substantial.

Sydney is sitting on 600-feet of porous sandstone, so for under A$100 I bought two 50-mm slabs of it.  The eight sorbothane hemispheres added almost A$100 but the overall investment was peanuts.  There is technical work needed to ’size’ the sorbothane installation so I guess it can be got wrong!  In other words, it can be fine tuned.

faustuss's avatar
faustuss
794 posts
 

@richardbrand 

 "the frequency is not specified, and I didn’t know what cu meant."

1kHz/5cm/sec

I guess the details allude you.

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