I'm surprised it took three responses to get to the SRA issue! :-) (Someone will probably take me to task shortly for running heavier than recommended.) However with only three responses total out of 90 views so far, and none of them saying yeah, I have also tried this and now do it routinely as well, the real takeway may be that I'm more of an outlier with this than I suspected.
I believe that it's the tracking force itself which affects the sound more than the SRA in this instance. The only way I have to determine this is comparing the changes in sound that I hear with adjusting the VTF against the changes I hear when adjusting only the VTA.
For now I'm leaving my VTA status-quo, although I know some audiophiles do adjust it for varying record thicknesses. In any event, I feel it's both simpler and more productive for me to play around with the tracking force by ear on a record-by-record basis and let the SRA fall where it may. (As with many audiophiles, I presume, SRA was never precisely determined in the first place and VTA was set by ear.) I humbly suggest trying doing this if you easily can, I would be interested in getting anybody's reaction. |
That's why we appreciate and depend on you Elizabeth! ;^) |
Again, largely disagree with this contention. Maybe I will try measuring any such change with my digital VTF meter, since some of you are positing not only that it exists but that it is significant. (Maybe some of you will do the same?) However right now I'm guessing that the small angular change effected by adjusting VTA even by several millimeters could only result in the most miniscule of VTF differences, perhaps on the order of one or two hundredths of a gram at most (the limit of most guages' resolution in any event).
But even if changing the tonearm height did more substantially affect the VTF, should you always necessarily want to change the VTA and the VTF in lockstep? Again I would submit that the fact that increasing VTF also has the side-effect of decreasing SRA (or vice versa) must be of more significance than whatever effect changing VTA has on VTF, but probably still not as sonically significant as the effect on the suspension loading and groovewall contact that a heavier (or lighter) tracking force has in and of itself. |
Dan_ed: I'm no expert, but I would differ with that take. My own (completely unscientific) opinion would be that a change in VTA, however small or large (within real-world limits), is virtually only a change in SRA, and for all practical purposes not a meaningful change in VTF. A change in VTF, however, could certainly produce a meaningful change in SRA, epecially with line-contact stylus profiles, as posters have pointed out. Still, as I said, I believe the changes I'm hearing when I make small changes in VTF are primarily the result of tracking force rather than rake angle, but both must be involved.
I don't change VTA on-the-fly, but I can change both VTA and VTF quickly and precisely with the tonearm secured. But as I mentioned, I tend to set and forget VTA (for any one cartridge). Then again, my collection is pretty much all standard-thickness original vinyl, not 180/200g audiophile reissues.
Jfrech: My table/arm is a Technics SL-1200 (modified, including with a fluid arm damper, but I don't believe that affects this parameter). The arm has calibration scales for both VTA and VTF so settings are repeatable, and neither requires tools to adjust. The VTF setting is quite accurate, even when adjusted multiple times, as I confirmed recently when I got a digital VTF guage in order to double-check my newfound preference for slightly heavier than recommended tracking forces with the vdH Condor XGM-MO cartridge. The fact that I upgraded my phonostage last winter (to an EAR 324) probably has something to do with this newfound fetish however; I doubt I would have noticed or at least cared about these small changes through my previous phonostages. |
Well, just shy of 300 views and no concurrences, I guess I'm alone here, and kind of surprised about it! Bet if I'd asked about VTA, instead of VTF, many would have said they tweak it record-by-record, at least sometimes... |
Hi D, I suspected that this factor might be brought up. It does seem obvious that it should be true in theory. However, I can't help but noting that virtually all cartridge manufacturers specify a recommended range for VTF that's wider -- oftentimes very much wider -- than the relatively narrow range I'm playing around within.
My takeaway is this: Even if the coil may not be perfectly centered in the magnetic gap, this fact in itself would pose no physical threat to record replay (as all manufacturers' specified ranges implicitly acknowledge). Since the 'perfect' setting is something I lack the tools to determine, and as you say is likely to change somewhat with conditions anyway, I can see no reason not to just go with the best or 'correct' setting being the one that sounds the best for any given record under the prevailing conditions (to me, in my system). |
I was looking at one cartridge manufacturer's website specs the other day where the allowable VTF range equalled 2.5g (obviously this was for a low-compliance design).
As I stipulated, there can be no debate about whether there exists some precise VTF at which a cart's internals will be best aligned. It is certainly open to question however, given the necessarily micro-variable nature of the beast, whether that force will also equal the best match to the compliance of the suspension, which I suspect is more consequential for the sound.
Onetwothreego: I wouldn't assume that just because your cart sounds best in the lower region of its range, that mine (or any other) would too, or that because yours sounds dead in its upper region, that me running mine in its upper region (and above) means I prefer dead sound that you wouldn't like. |
Possibly. In any case, whether the preferred VTF region happens to fall in middle of the recommended range, or above, my point is that it may be considered as a range, rather than a specific value, with room to tweak as desired. Clearly however I remain in a minority of one with this view. |
Hi Jonathan, thanks for injecting some authoritative input into the meanderings on this thread. What you say all makes sense to me, however I would still expect some session-to-session variation in optimal (or preferred) geometry to be probable with any cartridge, based on differences in prevailing environmental conditions affecting the suspension, as well as differences among the way records are cut (or from my perspective and ability to tell, simply in the way they sound). Do you disagree with my take that in all likelihood, there's no reason one should go really wrong as a listener by using the best tool we have available, namely our ears, to tweak these parameters, including VTF within reasonable limits, on a record-by-record basis?
BTW, I do realize (even though you chose for whatever reason not to say so as a disclaimer) that you are involved in the design and marketing of a cartridge line that is claimed to take into account the effect of tracking force on optimal coil alignment within the magnetic gap. This would of course seem to make obviously good sense -- in fact, so much so, that I actually have a bit of a hard time believing either that other manufacturers have never taken this factor into account themselves (whether they said so or not), or else that they didn't determine that it's in reality a relatively unimportant consideration as regards sonic performance. (One can't help but note that by implication, your cartridges too did not previously take this factor into account, or else that you knew about it but considered it to be fairly trivial.) Still, even if it's as much marketing as science, the concept does strike me as being a really good idea for a cartridge maker to tout, so bravo. Please feel free to comment!
FWIW: Yesterday I went ahead and made a bunch of VTF measurements using my digital gauge (the kind commonly selling for $80 from many outlets), for both the lowest and highest VTA adjustment settings possible with my tonearm, which amounts about an 8mm differential in height of the pivot point -- quite a bit broader an angular range than anybody would actually utilize for setup or tweaking of any individual cartridge.
First I confirmed the precision of the gauge (to within whatever limits are imposed by the quality of my tonearm bearings) by making many measurements without changing anything. As I have found before, despite the fact that these gauges have a readout to three decimal places, it's only to the second decimal place that readings are close to repeatable, to within an accuracy of about plus or minus two (i.e., a margin of error of about 4 hundreths).
I was pleasantly surprised but hardly shocked to find that, as I predicted, the variation in VTF (from a baseline setting of 1.5g) which accompanied the widest possible change in VTA, only amounted (on average, over about 30 or so repetitions of the readings for each VTA extreme) to approximately .02g (i.e., about plus or minus one hundredth from the force reading that could be expected at the middle of the arm's VTA range), which is of course within the gauge's margin of error. Despite there being some overlap in the force readings at each arm-height extreme, I do think this small average force differential is nonetheless real, due to the overall trends I observed over the course of the measurements, but that it is probably too small to account for any sonic differences, especially given that in practical use the actual VTA range will be quite a bit less than what I was experimenting with.
So my conclusion is that it's unlikely that adjusting VTA represents, consequentially speaking, a secondary adjustment of VTF as well. But I would welcome what any other posters' findings might be on this issue, if anyone cares to make the kind of measurements I did, perhaps using better tools and a more premium tonearm. Still, at the end of the day I didn't start this thread to get into such technical considerations -- I started it because of what I heard, and to see if anyone else had also heard and was doing the same thing in tweaking VTF to suit their listening of the moment. Continues to seem like not so much...
PS - All the adjusting and measuring I performed yesterday, along with subsequent listening, did have the beneficial effect of prompting to me to slightly raise my tonearm's baseline VTA setting in order to increase the SRA a bit, so as to offset the effect on the rake-angle of the somewhat heavier (on average) VTF I'm commonly running these days. My thanks to those posters who pushed me not to forget such interrelated considerations! |
Update: 800 page views now, but still no affirmative responses that anyone else tweaks VTF to suit individual records. |
Gosh no Joe, I'm nowhere near organized enough for that, I just go by ear for any particular record on any particular day. But since I assume some of this has to do with room temperature, which varies (and presumably little to do with such potentially label-specific attributes as vinyl thickness), I think that's the way it's probably gotta be. Please let us know what you find... |
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