rumble issues - see old thread update

hi guys

thanks for the further tutorials
this hs spinned into a very insightful thread

Richard is Richard Gray of the Power Company fame
he is an electronics guru and has set up a wide range of tables, arms and recognizes issues via scope, test records, etc

the Craz rack is fine - minimal suspension pads under denser surface material, titanium in the frame. It's the SRA VR platform above it that was causing the problems - these work miracles on amps, pre's, cd's etc but as we found out - the floating element is transmitting too much to the turntable

we replaced it with 3 cm granite and much lower resonance and speaker pumping. SOme in sync with the music, some not and probably in sync with the record. Sound doesn't seem to have added a shrill mid range

I also have a Billy Bags turntable stand my loricraft sits on - that sounds like some lugging I don't want to try

someone at a NOLA audiophile meeting last night suggested eccentricity in the spindle/bearing - but those Galibrier tables are built like a tank. I thought I heard the sligthest squeak the other night on a quiet passage - once a revolution. Do I need to re-oil it Dan?

low freq pre relates to it passing a lower freq signal - lower than my prior Dodd and Arc LS5.

salks ruler flat to 34 hz f3 under 29 hz f10 23 hz

I'l call Thom Mackris and Kevin at SRA for starters

I'll have to look into the record clamps
and yes I don't use the anvil but have seen records that it hurts on warpage more than helps

as Doug suggests - you get to the point where you are hearing all the eccentricities in musical reproduction

or as Richard said - compliant arm, compliant cartridge, comp pre, comp amp, etc - you are going to hear everything - warts and all

thanks

I think that if you filled the bearing all the way there should be no reason to worry about oil. There is no place for it to go. The bearing itself? Ah, no. ;-)

Got it this time. The one SRA turned out to not be a good match with the table. There is one layer peeled back, perhaps the only based on your results. BTW, have you tried the Gavia directly on the top shelf of the Craz? Heck, you could even move the Gavia to the floor since you're on a slab. Might tell you something.

I am not familiar with your amps and speakers, but it seems they are just going to move a bit with vinyl playback. Perhaps Atmasphere will have some input on this.

If things sound good, don't worry, be happy, and listen. Put the covers on if it bothers you. :-)

Tom,

I was just pointed to this thread. There's too much good inforamtion to sift through at the moment, but based on the names of the posters, along with a quick scan, it looks as if you've received good advice.

I likely missed some of the finer points, but here are some thoughts.

1. Same problem with all sources?

Do you get the same pumping when playing CD? I assume this isn't the case, but it needs asking

2. Changes in stands/shelves.

This strategy seems to be pointing you in the right direction. No time to comment on the apparent disconnect of suspending an unsuspended turntable.

The key point to mention however is, that with Vibraplanes, microscope tables, etc., the entire 'table is suspended - the critical relationship between drive system and platter is still intact.

Maintaining this fixed relationship between drive system and platter/bearing is key to the success of an unsuspended design, and placing the entire assembly on an air table is consistent with the design goals.

My expereience of a Townsend Seismic Sink on my turntables was essentially a whole lot of trouble for no improvement over a *well* *implemented* sandbox design.

I've never met Sorbothene that I wanted in the same zip code as my hi-fi, but I can't profess to having tried every last permutation. Let's just say that it's the last place I'd look for answers.

3. Cartridge.

Don't rule out the cartridge, just because the Tri-Planar/Universe is a ubiquitous and compatible combination. You might have a sample that's aging differently. Mount another cartridge. You've tried enough differnt things to not want to overlook this.

4. Oil.

It wouldn't hurt to re-lube as you've been running your rig for something like 3-4 years. I don't expect any changes here.

I'll try to work through this rather long thread as time permits, but don't hesitate to call me.

Cheers,
Thom @ Galibier

The key point to mention however is, that with Vibraplanes, microscope tables, etc., the entire 'table is suspended - the critical relationship between drive system and platter is still intact.

Agreed, and we go even further. In our setup the entire table + system + rack are suspended as a single entity, well away from the table and drive system. All our sorbothane floor supports see is a single, rigid mass of nearly 400 lbs. This is very different from sticking it directly beneath the TT feet or something. I tried that once, just for ha-ha's, and it sucks big time.

Agree that the connections between drive system, platter, bearing, plinth, armboard, tonearm, cartridge, LP and record clamp must be as non-compliant as one's components allow. The only compliance anywhere in our vinyl setup is Stillpoints instead of spikes beneath the plinth. As anyone who's tried them knows, they do ennable a tiny degradation of transient speed and dynamics, though most feel the reduction in sound floor makes for a worthwhile tradeoff.

It's about thoughtful implementation, as always.

Hi Doug,

Thanks for the clarification on your Sorbothene implemenation, as well as the validation that locating it closer to the source component is a non-starter.

Cheers,
Thom @ Galibier