Further Refining Your Setup

nce you have achieved basic setup, as described in the previous sections, there are two final areas in which you can refine or hone your setup. These are vertical tracking force (VTF) and vertical tracking angle (VTA/SRA). Tiny adjustments in these values can have significant musical benefits, but they must be conducted by ear and only after everything else has been fixed. They also interrelate, as changing the downforce will also change the VTA by depressing or extending the cartridge suspension. Therefore, it is best to start with tracking force and then refine VTA.

Tweaking VTF – This should be done by hand and ear, rather than by the stylus balance. Working from your initial VTF value, try adding and removing tiny amounts of tracking force. With threaded counterweights or 'arms with auxiliary downforce mechanisms, this is extremely simple. Unipivots with eccentric, sliding counterweights require more care to ensure that you do not disturb the azimuth setting, although some, like the VPI JMW, have a “hidden” facility to make this easier. In the case of the JMW, this is an allen grub screw that is positioned inside the counterweight stub. It can be adjusted precisely using an allen key to achieve small increments in VTF -- another case of ensuring that you are familiar with all of your tonearm’s facilities and adjustments before you start.

What should you be listening for? Small changes in VTF will afford you improvements in bass weight and solidity, but also the music’s sense of flow, the band’s sense of rhythm. Choose an album with these qualities (I often use one by Art Pepper or Duke Ellington) and listen for the most engaging sound. If you get lost, simply go back to your initial VTF using the scales and, once you’ve found a preferred value, check it and keep a note. If it is wildly different to the initial setting, your adjustments have been too big. Start again with much smaller movements. You should be aiming for the smallest steps possible.

Tweaking VTA/SRA – This is a slightly more controversial topic. Many observers suggest that the real impact of the small changes in VTF are actually the product of the resultant changes in VTA. Likewise, the impact of VTA changes will vary with tonearm type and stylus profile. However, what is not in question is that changes in VTA, normally achieved by adjusting 'arm height, have a significant audible effect.

Some 'arms offer Vernier-type VTA adjustment, graduated dials that allow micro-movement of arm height while the record is playing (examples being the VPI JMW, Tri-Planar, Graham and a host of others). These arms make VTA adjustment a cinch, as well as allowing the user to decide exactly how important it is to him or her. In some cases and with some extreme stylus profiles, that can mean adjusting the VTA on a record-by-record basis -- simple to do with these 'arms.

Other tonearms offer a single setting for VTA, normally derived from a spacer set under the armbase or a sliding post and collar as described above. In the case of the fixed-height and spacer arrangement (seen on the Rega 'arms) it’s pretty much a case of getting the 'arm as near level as possible and leaving it at that, with maybe one step either side in terms of spacer height as an option. Post-and-collar arrangements require time and care to adjust precisely, but it is worth doing, as it will have a significant impact on musical performance -- hence all those 'arms with adjustable VTA facilities. Increasingly, manufacturers are offering threaded posts with knurled collars to facilitate adjustment, and while these don’t allow for record-by-record changes, they certainly make initial setup considerably easier.

What should you listen for? There are two popular bits of wisdom about VTA, both of which are correct up to a point. The first suggests that optimum VTA can be heard by the sudden locking into focus of the soundstage; the second that VTA impacts tonal balance, lowering the 'arm producing a warmer, rounder sound, raising it a leaner, brighter presentation.

Both can be correct, but they actually reflect cosmetic results of far more fundamental and musically important changes. The tonal shift certainly acts as a worthwhile indicator of general position/direction of movement, but the real things to look out for are dynamics and timing. As you pass through the point of the optimum VTA setting, the music seems to get louder and much more dynamic, with crisper timing and greater drive and energy. The tonality/weight benefits and the crisper, more focused soundstage are just artifacts of the picture as a whole dropping into focus -- not so much spatially as in the time domain. VTA seems to have more to do with left/right channel phase relationships than it does with the actual orientation of the stylus and groove, but whatever the mechanism it’s importance to the best analog reproduction is both easy to hear and easy to demonstrate. Once again, incremental changes should be as small as possible. With post-and-collar designs, that can be frustrating at first, but it is remarkable how quickly you develop a feel for the process. Don’t overtighten fixing bolts, as that risks pitting the mating surface, making small adjustments almost impossible -- the 'arm will simply keep returning to the same position.

One final caution: when you set out to optimize VTA, especially if you are using a set-and-forget tonearm, make sure that the record you use is representative of the type you play most often. There’s no point setting VTA with a 180-gram audiophile pressing if you only own two of those and your other five hundred records are all 120-gram discs.