Low Frequency Rumble Question

On the CSO Reiner disks, it is the Chicago Elevated trains fondly known as the "L" going around the Loop tracks. The tracks are right behind Orchestra Hall. There are other random low frequency noises that the Ampex recorders could record but the engineers couldn't hear on the Altec monitors due to their low frequency cut-off. These are on the CD remasters also. I own several vinyl and CD incarnations and low frequency noises are a regular feature.

Solti was a real podium stomper (I saw him live with the CSO numerous times) and you can hear this on many Decca recordings.

Rcprince -- Thanks for your response. The rumble also appears on some of the RCA Reiner Chicago SO records. I don't think those were made in England.

I also noticed an interesting fact. I have the Classic Records 45 rpm "comparison" LP of Shostakovich's first symphony with Martionon conducting the London PO. The rumble appears in various places on the 33 rpm disc, but NOT on the 45 rpm discs. Go figure???

I'm just worried that there is some weird incompatibility between my cartridge/arm. But I suppose that if so it would show up in many more places.

Thanks again

Jackcob, what records specifically are causing this rumble? That will give a clue. Like I said before, the Underground's rumblings are clearly audible on the British RCAs, throughout the recordings, and Classic's reissues are good enough to capture them (that's one of the reasons Carnegie Hall and Trinity Church in NYC are not favored recording sites, good as their acoustics might be, as the subways are clearly audible, and felt, in those places). Only other alternative I can figure is whether the records have any warps.

By the way, there's a story as to one of the London halls which was an excellent recording venue until an Oriental rug dealer went out of business--he stored his rugs under the main floor, and when they were liquidated their damping effect on the Underground was lost, making it impossible to record there without too much interference from the trains.

Seeing that the problem occured only on a couple of albums, I would tend to think that it is those albums that are the problem. However, you may want to clean/inspect/re-lube the main bearing on the Linn.

A resonance problem would possibly manifest itself by mis-tracking. Mis-tracking might be apparent either sonically or actually seeing the arm jumping around excitedly or both.

Take a look and let us know...

Regards
Jim

Thanks for the responses. I checked last night and I can hear the "rumble" through headphones with no sound coming through the speakers. So it seems it must be coming either from the recordings or from some problem with the arm/cartridge combo (ekos/vdh black beauty).

The "rumble" sound is so pronounced, it is hard to believe that it is on the discs themselves. Could it be a "resonance" problem, whatever that means?

Both Joe and Rcprince are right on the dot! You can even discern very nicely which way "the tube" is going!
Cheers,

Many of the RCA records recorded in England (for example, the Faust/Carmen or Royal Ballet Gala records), like their Decca counterparts, have glorious reproduction of the London Underground going by under the hall in which the recording took place; the Heifetz recordings often have a low frequency content that may be someone moving around on the podium(?)--for example, the Bruch Scottish Fantasy. On my Shaded Dog of the latter there is no problem, but Classic's records have much better bass extension, which in many cases is a mixed blessing. That may be what you're hearing, assuming your speakers can get into those nether reaches. Ah, wish my pre had a rumble filter!

Based on yr description, it may be feedback brought on by subsonic content in THOSE recordings. One way to test this theory is to listen on headphones with the speakers silent-- if your system can do that -- to see if the problem goes away. If it does, then you need to do a better job of isolating the turntable from acoustic vibration.
Best of luck,
Joe