ZYX Universe - Unipivot or Dual Gimbal arm

Lots to cover in this thread ... I'll try to pluck off a few salient points.

I feel a bit odd, being in the middle of this ZYX love-fest, but I have to admit that they are mitey-fine cartridges. I have to agree with Raul however that the Dynavector XV1-s is also extraordinarily good. To date, these two marques are my fave.

Regarding the RMAF and my main room, one characteristic of the Exemplar horns we had at the Rocky Mountain Audiofest is that they can be a touch "hot" in the 2.5K to 3 KHz region. Several owners and I have been collaborating about this, but alas, the show deadline quickly approached and I had no time to act. A crossover parts upgrade has been reported to ameliorate this low treble bump.

I've been playing with Bastanis loudspeakers since returning from the show. They're definitely better behaved in this region, although like any transducer, they are not perfect. After their 400 hour break in (they're working on reducing this through an accelerated burn-in at the distributor's), I'll know more about them.

To Doug ... adjust azimuth visually for starters as you currently do, and then perform your fine adjustment by ear. Listen to female voice for imaging, depth, and best dynamic behavior when she belts it out. Azimuth when properly adjusted will transform the sonic images from a flat cardboard cutout presentation to one with real bodies in space.

Electronic adjustment of azimuth (for equal output in both channels) loses site of the fact that in doing so, you may end up with the stylus not sitting squarely in the record grooves. It's an unfortunate reality that cartridges cannot be manufactured perfectly.

Of course, if you're lucky then you will have the best of both worlds - equal output and while riding squarely in the groove. Better lucky than smart ;-)

If you adjust to track squarely in the groove, you may suffer a slight channel imbalance. This is an argument for either dual mono volume controls or a balance control, and not for adjusting your azimuth for equal output.

The first goal should always be to align the stylus with the groove.

Cheers,
Thom @ Galibier

Hi Larry,

Was this a session where Frank set everything up?

The reason I ask is that you can exercise in enormous amount of control in how much energy you release into the tonearm based on how tight the cartridge screws are. This can have a dramatic effect on both dynamics as well as a perception of brightness, and tighter isn't always better. You need to experiment with each arm/cartridge combination.

We're talking about minute changes - 1/32 of a turn of the cartridge screw. If you were unaware of this cartridge bolt torque parameter, you'd never guess that your setup was suboptimal. It was at the feet of Herr Schröder that I learned this only last year. Please take this comment in the spirit in which it is offered.

Now, if one were to lay out a hierarchy of brightness (an orientation toward the upper frequencies), then the Graham 2.2 would be the brightest of the three tonearms. I don't think anyone on this list would disagree with this statement.

Certainly, the Universe is a more refined cartridge than the Airy-3, exactly in the areas you report. Any of these weaknesses would then be exacerbated in the Graham - especially if it were suboptmially mounted.

I don't think that this is a gimbal vs. unipivot issue, but rather an expression of three different designers' aesthetics.

As I've written before, I have an immense respect for Bob Graham, even though I've been beaten up on this forum in the manner in which I expressed it. Bob knows what he's after and achieves it. His gimbaled bearing Robin sounds very much like his 2.2 - achieving 90% of its performance (when you swap out the arm cable) at 1/6 the price. I've heard that he's made great leaps with the Phantom and am certainly interested in hearing if first hand - of course, in a world-class turntable like a Galibier .

Cheers,
Thom @ Galibier

Hi Larry (Cello), Doug, all ...

Every time I'm around Frank, I learn/modify my knowledge base.

About 6 months ago, I had a Lyra Parnassus in house. This cartridge has an extremely tall cantilever. I got to thinking about this (there you go again ...Thom).

With a mirrored surface like the one on my protractor, it seemed to make sense to perform an initial azimuth setting referenced to the stylus instead of starting with a horizontal headshell. The stylus is after all, the business end of things.

Of course, I got in the habit of doing this with all of my cartridges as I got used to sighting in on the stylus.

At the RMAF, I gave my 'table a preliminary setup on 4 hours' sleep - knowing that Frank would pass by to do the final tuning the next morning. A fellow can get pretty lazy (tired?) knowing that Herr Schröder will ride into town on his white horse.

Frank took one look from a few feet away and noticed the slight tilt in the headshell. He commented that there's no way that he would trust his own eyes to perform the initial setting by referencing to the stylus.

Of course I saw this tilt, but I viewed it as an indicator that the stylus was not perpendicular to the body - as evidence of manufacturing tolerances needing to be compensated for.

What's interesting about all of this (yes ... there is a point to this story) is that I found that by using this technique, I could still dial in a sweet spot in the azimuth. It was just not *the* sweet spot. Just as with VTA/SRA, you can get false nulls at various points along the adjustment continuum.

We've seen this with VTA/SRA adjustment, where you can drop the arm post so much as to actually start to increase the high frequency content in the playback.

With respect to azimuth, you can be off by a relatively large amount (let's say, 2 degrees for sake of argument) and within this range, find a place where everything locks in (let's call this place 2.15 degrees in this example).

This "locked in" place can end up being a false null, with the true zero point (again, just an example) being a rotation of perhaps .2 degrees.

The moral of this story is that starting with a level headshell is the safest place to start your adjustments from.

Cheers,
Thom @ Galibler

Hi Roger, Doug ...

The fascinating revelation for me was the discovery of multiple null points (false nulls) which brought me no comfort in the least. I believe I described this in a recent thread (this one?).

Failing instrumentation, we're left with starting out with a headshell that's parallel to the record surface (in the azimuth plane), and beginning our adjustments from this point.

The is a leap of faith that the cantilever/stylus assembly is within reasonable manufacturing tolerances so that the null you hit (by ear) is the real one. The thing we have going for us is that minimal crosstalk will also yield the lowest distortion, because the stylus will be sitting squarely in the groove.

If you're troubled that perhaps you are one null away from the truth, then you can always go counter clockwise by one null and also clockwise by one.

Rather than reiterate Brian Kearn's brilliant post you pointed the group to, I suggest that everyone take a moment read it. Even if the math confuses you, I suggest you read it and file it away for future reference. Come back to it from time to time. You'll be amazed at how things like this begin to make sense over time.

One key point to focus on is midway into this post, where Brian hits the nail squarely on the head:

"I disagree with this method of calculating crosstalk. It does not take into account the effect of channel imbalance on the crosstalk measurement. In effect this method assumes that a cartridge has perfect channel balance."

Cheers,
Thom @ Galibier