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u-turn AUDIO Basic Turntable

Orbit Basic Turntable

Review, Impressions, and a Few Measurements

Yet Another Turntable?

This website started when I needed another turntable. I bought a Pro-ject Carbon Debut Turntable, didn't like it (more about that later), and returned it. My latest acquisition is u-turn AUDIO's Orbit Basic Turntable. The one word review: WOW! Read on for the details.

First Impressions

It took a little more than a week from when I ordered the table until it arrived. It was well packed and arrived in good shape. I also ordered the cueing lever (not included in the basic), which arrived a few days later.

Assembling the table was quick and easy. The instructions were clear and simple to follow. It comes with an Audio Technica AT91B cartridge pre-mounted, aligned, and balanced. The cables fit snugly onto the RCA connectors on my preamp as well as those on the turntable. The turntable is powered by a small wall-wart.

The belt that drives the table seems a bit improbable in the way it fits around the outside of the turntable platter. I dropped the belt over the 33 RPM portion of the spindle and around the turntable. Then I turned the turntable on, and allowed it to spin a few times, which centered the belt on the rim of the platter. The black platter seems to be made of some kind of dense fiber-board, seemingly quite uniform and accurately machined. The table comes with a black turntable mat.

The cueing lever installs easily without any tools. The dust cover looks good, but the hinges are kind of basic, so the dust cover really only has two stable positions, fully-up and fully down.

I powered it up and got my first thrill. Mechanically, it is very quiet. Stand next to the turntable and you can't tell whether it's on or off. There's a quiet little hum from the wall-wart (in my case it was mechanically amplified by being plugged into an outlet strip that was screwed to the particle-board shelf on which the turntable rests) that is present whether the turntable is on or off. If you put your ear next to the table as it turns, you can hear a very soft, periodic noise as the belt traces its way over the turntable rim, but the room must be very quiet, and you have to be quite close to the turntable to hear it. The purring of a small cat sitting about 8 feet away was louder than the turntable noise at 2 or 3 inches.

Now it was time to power up the associated electronics and check for hum and noise. At first, I was a bit concerned as this table doesn't have a separate ground-wire connection. No worries, it was pretty quiet (hum). You could hear hum with your ear near the speaker, but from my normal listening position the only hum I heard was mechanical noise from the Dynaco Stereo 150 Power amp transformer that I'm currently using.

With the preliminaries done, it was time to actually listen to music. The record was Dexter Gordon's Manhattan Symphonie, the cut was "Body and Soul". The results were very encouraging. The cueing mechanism, though not damped, was direct and controllable, and allowed me to settle the arm into the lead-in groove with no fuss. The lead-in groove was quiet and seemed rumble-free (measurements to follow).

The music was great. No mechanical noise got in the way of the music. Oh, that's nice. From the opening notes, to Dexter's quotes of 'Round Midnight in his unaccompanied solo section, it was great to just hear the horn and the echo without the turntable noise. I listened to a few more cuts...clean and quiet, and thoroughly enjoyable. The lovely prize...this table (and cartridge) cost just $179 plus shipping, plus the cost of the cueing lever ($40). So for less than $250 delivered to your door, you get a turntable with seriously good sound. Wow!

Measurements

It's always illuminating to see how the measurements compare with the listening impressions. Given my recent disappointing experience with the Pro-ject Debut Carbon, I thought I'd start with rumble and noise measurements. Spoiler alert...right out of the box, the U-turn rumble is 6 dB less than the Pro-Ject debut carbon after tweaking!

Rumble spectrum

Note that the reference level for a 1 kHz 7 cm/sec tone is -5.66 dBv. The next picture shows the hum spectrum with the arm up and the motor off (e.g. no rumble) was mainly a 60 Hz harmonic at -51.66 dBv.

hum spectrum without rumble

The speed accuracy was dead on. I measured a 3150 Hertz tone and read the frequency off a spectrum analyzer with span from 3100 Hz to 3200 Hz. The spectrum of the 3150 Hz was about 11.76 Hz wide, and perfectly centered on 3150 Hz.

There was a bit of modulation on the 3150 Hz tone, as evidenced by the 11.76 Hz width of the reproduced 3150 Hz tone. You could hear a bit of wavering on the test tone, but it was subtle.

Comparison with Pro-ject Debut Carbon

Caveat: I have only seen and evaluated one of each turntable, but given that caveat:

Conclusion: I much prefer the u-turn, and no longer have the Pro-ject

Long Term Reflections and Annoyances

So, as of this writing, I've lived with the turntable for about 1 month. Am I as positive as I was when I wrote the previous paragraphs? Not really. It's still ok, but I've found a few annoyances.

My plan is to contact Uturn to see if they will replace the belt, or if they have any thoughts about these issues. I'll report back once I know more. In the meantime, here's a youtube video that shows a representative sample of the belt wander, but no means the worst of it all.

Here's a video that shows the dustcover interferes with platter rotation if you hold it in the center. You must hold it by the edges to avoid slowing the table. I'd say that really shouldn't be like that!

This shot shows both the belt on the turntable rim and the drive pulley in the same picture. Posted at request of Uturn Audio tech support to troubleshoot belt wander.

Here's a direct side view of the belt and pulley before the belt was re-seated (suggested by Uturn Audio Tech Support)

Here's the same view after the belt was reseated. It's better, but there are still a few wide excursions...look around 32 seconds. This video was taken within a few minutes of having re-seated the belt. Note: after about an hour of continuous running after the reseat, the belt wander is about as bad as it was prior to the re-seat. This doesn't really seem like a solution.

Here's a view from the top of the pulley and belt (after re-seating)

Some Good News

I reported the problems listed above to Uturn. Their response was pretty quick, and was done by someone who understood the product and the problem. The couple of videos shown above were part of their remote diagnosis. As a result:

Orbit Basic Turntable

They shipped a new dustcover (no charge). It was quite straight at the front, not bowed like the first one. That was enough to provide adequate clearance to the belt that deflection from pushing on the center of the dust cover when raising it caused no problems. I'd still say that the clearance is a bit close, but there is now clearance.

They also sent a new spindle and belt (also no charge). The new belt seemed a bit more snug. The new spindle seemed to have less friction as it spun. The "belt wander" was rather less after the change. Take a look at the youtube above. It's still not perfect, but I think it's a very good improvement.

Rumble spectrum

It seemed the table was quieter, too...So I measured the rumble. I may have a slight absolute calibration error, but the quite significant thing is how much the 240 Hz rumble component dropped. Previously, the 240 Hz component was just about 3 dB less than the one at 120 Hz. Now (see the picture above) the 240 Hz component is about 17 dB less. That is huge!

Yet another update

One day has passed since the previous installment (new belt, new spindle). The belt is back to wandering...oh well. Sound seems ok...I wonder if the belt wandering is one of those things that you just live with...not pretty, but doesn't hurt???

The Last Word?

I sent the turntable back to U-turn audio, less the dust-cover, cueing lever, and power supply. They got it back to me in about 1 week. Here are their notes:


"Hi Dan,
Here are our service tech's notes on this repair:
"returned spindle, platter, belt. no cart cover but stylus appears fine (giant dust ball crusted on). belt wasn't wandering too too much. platter is ok. spindle is tight - replaced. belt has low freq - replaced. no belt wandering and WF has improved to less than .15"

I checked this out when it came in, and was surprised to see that the belt wander was much less than in your video. This makes me wonder if maybe you are twisting it a bit during installation. (My response: Before this last return belt would start out ok, then increase wandering dramatically over a few hours of use). Also surprised to see all the debris on the stylus - did you hear this at all?(My response: yes, but I didn't want to damage the stylus by cleaning it...What method do you recommend?).

It makes sense that there would be more rumble if the belt is a bit tighter (looser belts generally mean less rumble). There may be 1-2mm of length variation between our belts. We do a qualitative fit test with each belt, then do two stages of wow & flutter and frequency deviation testing (one set of tests on a reference table, and one set with your particular table). We generally let the numbers dictate if the belt is a good fit or not. The tight spindle probably made your previous belt feel looser than it really was.

The rumble is one place an acrylic platter would help out, as the acrylic is really good at killing these motor resonances. There is also less friction between belt/platter with acrylic - good for noise reduction and speed consistency.
-Ben


To me it seemed that the belt they supplied was much tighter. As you can see from the picture below, the belt-wander is much improved. The pitch constancy is also much better. At some point, I'll re-do pitch stability and rumble measurements to see what changed, but I think we've reached the end of the belt-wander/pitch problem. You can see what it looks like in the youtube below:

BTW, Ben recommended the ONZOW Zerodust for needle cleaning. I have one on order now.

A Parting Thought for Now

Every manufacturer has problems now and then. The difference is how they support you and the product to work through to a successful conclusion. Uturn gets a solid A from me.

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