Feel Silly Asking This Question Alignment Parameters

Dover, I’m not quite sure what the argument is really about but my calculations suggest that a change in EL from 222mm to 225mm would increase effective mass by only about 2%.

@lewm 

The OP wants to use an ARC protractor.

As I pointed out earlier, changing the effective length means a different ARC protractor will be required. This is likely lost on many readers.

Unfortunately for many readers who struggle to understand how to set up a TT properly, arbitrarily changing the pivot to stylus distance outside of the manufacturers specifications could lead to disaster in terms of reasonably accurate set up.

You might be quite comfortable with this because you have many years of experience setting up TT's. Unfortunately most don't.

The whole purpose of the OP's question was to address concerns that he had on set up. The word and numbers salads tossed up in this thread - encouraging others to ignore manufacturers guidelines - is a recipe for disaster.

Whilst you might be happy with this, because you enjoy intellectual debate, the reality is, for newbies, confusing them often leads to frustration and disappointment.

Consequently we lose another turntable enthusiast.

Why do we care about folk losing enthusiasm for turntables - well, in a dwindling market, prices rise, the market shrinks further and eventually innovation declines and the market dies.

Have a look at the declining numbers on this forum.

Therefore as you and I and some others on this thread have over 30 years of experience in setting up turntables - it is incumbent on us to help folk with their turntable set up advice by keeping advice simple, accurate, and explain in a way that is easily understood.

I agree with all you say above, but I just wanted to point out that increasing (what I thought was EL but my in fact be P2S) from 222mm to 225mm has little effect on effective mass, which of course has nothing to do with alignment per se. If we are actually talking about P2S, then the net effect on effective mass of the commensurate increase in EL would be even less than 2%.  But for EL, if effective mass was 20g at 222mm, it would be ~20.4g at 225mm. (This is very inexact, just comparing the square of the two numbers, which is directly proportional to effective mass.) 

Looking back on my nearly 50 years in this hobby, I would unashamedly say that there are some things I did wrong for 40 of those years, some other things that I did wrong for 30 years, and some more unknown things that I am doing wrong even now.  (Not speaking only of tonearm alignment.) For the uninitiated or newbies, they should know it's a marathon, not a sprint to get to audio Nirvana.  But such is our capacity for self delusion that one can enjoy the hobby from the get-go, just keep an open mind and hope to get better at it.

@lewm : Well said.

Dear @lewm @wrm57 : MINT LP disapeaed of the market and was one of the first protractor with dedicated turntable/arm, specific . Was really inexpensive.

The dedicated, one only, alignment hasd a way high limtations for the owner and for the cartridge against universal pro-tractors as the Feickert protractor.

If I will live for ever with that tonearm/TT alignment maybe no problem ( just maybe ) but it does not gives any single advantage over the universal protractors that gaves us to achieve the best quality level performance for any cartridges and tonearms combinations and or different kind of aligments. Ar the end we have try that the cartridge can shows at its best and a dedicated protractor can’s do it, probably at random but who knows.

Newcomers must know that could be a big mistage to get married with that kind of protractors and that the best " road " is a Universal alignment protractors. In the other side the OP posted that he wanted to optimize about and maybe he does not achieve it.

R.

@rauliruegas : Good advice, for sure, to get a universal alignment protractor if you’ll be changing out arms. Just moments ago, in fact, I took delivery of a new SmartTractor. We’ll see how it goes. I’ve always had a preference for dedicated arc protractors, dating back to my first WallyTractor in 2000, and have them for all my arms. But the eyes are not what they were and won’t be getting better. I think the one-point process should be easier.

BTW, Wally preceded Yip at MintLP in bringing dedicated arcs to market, if I’m not mistaken--at least in my awareness. Mints are excellent and missed. JR now offers the generously-named Universal WallyTractor, which has many curves but not all, although he will still do a dedicated protractor at a very high price. I’ve never used or even seen a Feikert but it has a big following.