The Sota Cosmos Vacuum Turntable


People have been requesting I publish a review of this turntable and like most of life lately this has become more complicated than expected. I ordered this turntable during the pandemic when Sota was short of help and stressed to the max. It should be no surprise that things did not go smoothly. The end result is however very positive and that is what counts. As a reminder the tonearm is a Schroder CB and the cartridge a Soundsmith Voice. My current phono stage, an AR PH3 SE  works best with high output cartridges and the Voice is as good or superior to low output cartridges costing up to $5000 maybe more.

The turntable came with several defects. First was the vacuum seal on the platter was rubbing the motor cover. That was very easy to fix by chamfering the inside edge of the motor cover. More difficult was a wayward motor control unit that shifted speeds when it was turned on in a irregular fashion. The two control units for the Condor and Roadrunner had been condensed into one chassis with a new switch arrangement and the logic for the switching was defective. The unit was usable, you just had to pay attention to what speed was actually running. The programming was corrected and new units made within 4 months. I just got the new unit last week and it works flawlessly. I also got a free spare belt along with the unit. 

Two other issues became evident with use. One is the feedback issue that many are familiar with from a previous post. That has been corrected. I use boosted subwoofers which is difficult for many turntables to tolerate. The Cosmos is totally impervious to them now. The last issue is the adjustable feet have a little play in them which allows the whole table to wobble a tiny bit when the dust cover is lifted causing the turntable to skip. Part of the problem is that the spiked feet can slide easily on the granite surface the table is planted on. This has been solved by locking the plinth to the granite below. I can now man handle the table without ill effect. 

Now for the positives. The vacuum system works on all but the most warped records and if you push the warps down into the platter at startup you can get those to seal also. In the last 4 months that has occurred with two records. The speed control system will maintain 33.333 +- 0.002 rpm all day long regardless of anything else that is going on. I use a conductive sweep arm that causes more drag. The turntable could care less. No other turntable I know of displays the actual speed of the turntable down to 1/1000th of an rpm. Nothing disturbs this turntable. I could hit the granite with a sledge hammer and it could care less. I can bang on the plinth directly with a hammer and the volume all the way up....nothing. The wooden plinth is sort of rustic but the underlying sub chassis is beautifully machined billet aluminum and the tonearm board is a boat anchor and beautifully finished. The dust cover is also top notch, optically clear, thick acrylic.    

What does it sound like? Nothing. It actually gives you the sense in terms of speed regularity that you are listening to a digital source. With the advanced motor control and vacuum clamping the speed regularity is stunning. Any warping creates speed irregularities that far exceed those of even middle of the road tables. Vacuum clamping sucks those warps right out resulting, in most cases, in a perfectly flat record that is as thick as the turntable's platter. The vacuum pump makes a tiny bit of noise as it is sealing then is dead silent. I can play records at volumes that would overwhelm most turntables. 

How does the Sota fit into the hierarchy of turntables? The Sota Nova Vacuum is less expensive and gives you 99% of the Cosmos's performance. The next tables above it cost wise are the SME 20 and 30 series tables followed by the Basis Inspiration and the Dohmann Helix. The Cosmos costs 1/6th what the Helix costs and I would think that makes the Sota quite a value. I have to admit that I am biased and will only consider isolated, suspended turntables, descendants of the AR XA's landmark design. There is always the DD vs BD debate. Lack of vacuum clamping immediately disqualifies any turntable from the speed consistency contest. It does not matter how accurate the turntable's drive is. Without vacuum clamping it might as well be an old idler wheel design. If you have a hard time believing this is true play a 1 kHz test tone and stick a tooth pick under the edge of the record and listen to what happens. 

If you have 10K to spend on a turntable and do not have to have the glitziest looking table around the Sota Cosmos vacuum is a very strong, IMHO the strongest candidate. I bought one and I could have spent twice as much. If there is another turntable in my future it will be a Dohmann Helix, at least for the time being. Sota is a pleasure to deal with. They responded quite appropriately to issues and will not hang you out to dry if problems develop. 

 

128x128mijostyn

@sbank , about time you showed up 😀 I sure did mention how quiet the pump is! Mine is buried behind the bottom row of records right under the turntable. If it is quiet in the house I can just make it out as it is sucking the record down. Once the vacuum is established the pump slows way down and becomes inaudible. If the pump can not establish a vacuum because the record is severely warped it will run for about one minute then it will stop.

There are tables that are fancier and cooler looking than the Sota Cosmos but none that do the job significantly better.

@sbank Nice to hear that you are enjoying the Audiomods V.   I still have an armboard for a Rega geometry arm like the Audiomods...I bet my Ortofon A90 would sound great on it. 

Anyway, I bet it works great with your Sota, the real subject of this thread.

-Karl

 

@mijostyn

You suggested somewhere in this thread that the Nova VI (and now the VII?) comes to within 99% of the Cosmos. I believe the latest Nova with the full Eclipse package and vacuum prices out at around $8500. The comparable Cosmos prices out at $12,000. (Incidentally, several people have pointed me toward the 4point9 to be installed on the Nova.)

Generally I attempt to justify incremental improvements, notwithstanding the expected diminishing nature of the sonic returns. I know the sub-chassis on the Cosmos is theoretically superior to the Nova. My question to you, do you believe there is a PERCEPTIBLE sonic difference between the two tables that could consistently be identified in controlled blind tests? Maybe this is my longwinded way to answer my own question that the $3500 Cosmos/Nova difference might be better invested into an even more capable cartridge?

The $3500 difference could be considered to exchange the Suspended Aluminium Plate for a Phenolic Densified Wood.

The Link has been discovered since my becoming an advocate of this material, the testing shown must certainly show where there are properties present that are making the Densified Wood an attractive material, when used for Plinths, Chassis and Sub-Plinths.    

This thread provoked my memory. I indeed had one of the very early SOTA vacuum hold-down tables. And yeah, there was more there there, no matter what LP I put on. When the vacuum hold-down eventually went south, I believe the company offered me a deal on a non-vacuum hold-down platter. I said yes. The machine still runs just fine, maybe another fifteen/twenty years on.