Nsgarch,
Your suggestion to use small VTF adjustments as a proxy for fine-tuning VTA/SRA would indeed have the effect you described. Unfortunately, VTF fine-tuning does more than center the coils in the magnetic field. A fairly large increase like .2g would cause other effects that might fairly swamp the VTA/SRA change.
As Andrew described and I affirmed, a change of .05g or even .02g can have a significant impact on sonics. These tiny changes barely effect the coils/magnets relationship, yet if we're near the cartridge's VTF sweet spot they have significant sonic effects. Why?
I believe the reason has to do with a kind of mechanical damping. Increases in VTF increase pressure between the suspension and cantilever, by definition. Once we have sufficient downforce to assure clean tracking, additional pressures very quickly become detrimental. HF response is dulled, micro-dynamic shadings are lost, the music goes dull, drab, lifeless - in a word, overdamped.
Our anti-skating experiments (described on other threads) support this understanding. Anti-skating, like VTF, increases pressure between suspension and cantilever. Using more than necessary to maintain clean tracking sounds exactly like using too much VTF. HF response is dulled, micro-dynamic shadings are lost, the music goes dull, drab and lifeless - in a word, overdamped.
For the sufficiently obsessed (Andrew and I know who we are!) increasing VTF as a proxy for adjusting VTA/SRA would produce unacceptable side effects. Of course Raul did observe that Paul and I play our rig right on the edge. He was certainly right about that. ;-)
Doug
Your suggestion to use small VTF adjustments as a proxy for fine-tuning VTA/SRA would indeed have the effect you described. Unfortunately, VTF fine-tuning does more than center the coils in the magnetic field. A fairly large increase like .2g would cause other effects that might fairly swamp the VTA/SRA change.
As Andrew described and I affirmed, a change of .05g or even .02g can have a significant impact on sonics. These tiny changes barely effect the coils/magnets relationship, yet if we're near the cartridge's VTF sweet spot they have significant sonic effects. Why?
I believe the reason has to do with a kind of mechanical damping. Increases in VTF increase pressure between the suspension and cantilever, by definition. Once we have sufficient downforce to assure clean tracking, additional pressures very quickly become detrimental. HF response is dulled, micro-dynamic shadings are lost, the music goes dull, drab, lifeless - in a word, overdamped.
Our anti-skating experiments (described on other threads) support this understanding. Anti-skating, like VTF, increases pressure between suspension and cantilever. Using more than necessary to maintain clean tracking sounds exactly like using too much VTF. HF response is dulled, micro-dynamic shadings are lost, the music goes dull, drab and lifeless - in a word, overdamped.
For the sufficiently obsessed (Andrew and I know who we are!) increasing VTF as a proxy for adjusting VTA/SRA would produce unacceptable side effects. Of course Raul did observe that Paul and I play our rig right on the edge. He was certainly right about that. ;-)
Doug