Cartridge too light?

So I finally (finally!) got my new tonearm, an Incognito RB250, and am currently in the process of installing it. I've run into a snag. The cart (an Ortofon 520Mk II) seems to be too light for the arm. Using a Shure tracking force gauge, the force with the counterweight screwed in all the way (i.e. greatest tracking force) is only about 0.7g. Needless to say, this is considerably lower than the manufacturer's recommendation (1.5g, with a range of 1.25 - 1.75g).

However, if I follow Rega's guidelines for setting the tracking weight roughly - set the weight so that the arm floats with the stylus 1mm from the record surface, then from there a half-turn inwards equals approximately 1g - I can set it to roughly 1.5g no problem, with the counterweight still a good turn or two out from the full-in position. Now I know the Rega method isn't going to be very accurate, but it shouldn't be too far off, right?

The other thing that's making me doubt the Shure's measurement is that the new arm sits quite a lot lower than the old R200. As such, even with the resting platform thing (the little platform that holds the arm clear of the record surface, for cueing up the record - what's it called?) at the "up" (and "clear") position, the stylus rests on the balance (i.e. I can't use the cueing platform to lower the stylus onto the Shure gauge because the platform doesn't hold it high enough, if you see what I mean). So not only do I have to lower the stylus onto the gauge manually (which is a bit nerve-wracking and fiddly), but it also leads me to doubt the gauge's validity in this circumstance...

Has anyone used an Ort 520 with an RB250? Is it a workable combination?

Should I just go with the Rega tracking force setup method, and tweak it by ear? I think I'll give it a go next (and I'll try out the HFN test record to check for problems).

Help!

Dunc

 

Quick update - threw the HFN record on with the counterweight set by the Rega method and it played the intro tracks fine (tho surface noise & pops 'n things were louder than I remember), but the first anti-skating test track produced a buzzing in the left channel. So after much fiddling with the anti-skating setting and tracking force I've at last got it to play the first three anti-skating test tracks with no buzzing! Score! (I'm not going to bother testing the 4th "torture" track...) The setting I ended up with is basically both tracking force and anti-skating on max. Anything less and I'd get buzzing in one channel or the other, or both. This way, no buzzing. So - now to try some real records!

But before I get carried away, am I likely to be making a big mistake, setting everything as roughly as I have? I'm not going to bugger my cartridge (or records, for that matter) am I?

Dunc

 

although i used the incorrect terminology in another post,there have been several threads in Vinyl world regarding setting the anti-skate to max,this allegedly 'switches off' the anti skate,and the users then tune the deck by ear using just the vtf

cant say i heard any difference

 

Sounds wrong to me. The arm sounds too low. How deep is the cartridge? You might need to put shims under the arm mount (you can get them from Rega in a variety of sizes).

A smidgeon too much tracking force is better than too little, but you don't want too much. That Shure gauge is pretty accurate IME, something definitely sounds amiss. As for anti-skating, generally you should be able to get away with less rather than more if everything else is setup properly. It sounds to me as if you have too much tracking force.

Have you still got the instructions for the Shure? Bear in mind that at a certain force you have to double what's showing on the gauge to give you the actual tracking force (the instructions give the details).

Edit: here's the instructions in PDF format:

http://www.shure.com/pdf/userguides/guides_phono/sfg_2.pdf

So, the gauge showing 0.7 means the tracking force is actually 1.4. If you have it significantly higher or lower than the manufacturer's recommendation you can, indeed, damage your vinyl.

-- Ian

 

You bought this from the dealer who'd sold you a faulty early Rega arm? They really should have sorted it out for you.

If you had a standard RB250 then the Rega instructions would work. Otherwise probably not.

Paul

 

Okay, I don't know what kind of crack I was smoking before (not really the best habit to combine with turntable setup, eh?) but the Shure gauge seems to be measuring like a sane thing now, much more in line with the rough Rega tracking force setup method. I still have to lower the stylus onto it manually but at least it's reading right (or, er, I'm reading it right...)

But so now I have another problem. Using the Shure to set the tracking force to 1.5g as per Ortofon recomendation, I can't get the 2nd or 3rd anti-skating tracks to play smoothly (from the HFN disc). And I don't mean the anti-skating's off - I can get that set right (so no one channel is buzzing) on the first test track, which plays smoothly. But the 2nd and 3rd tracks have buzzing in *both* channels. Which implies that anti-skating is not the problem.

From what I understand, it implies that the tracking weight is too light. Fair enough, but if I set it to the max recommended tracking weight (1.75g) the buzz is still there.

Argh!

So, from what I can see, the only way to get it to play the HFN test tracks smoothly and with no buzzing is to do what I did before - and just max out the tracking weight. But although I haven't measured it with the Shure, I would guess at that setting it's at 2g or more. Which is well above what Ortofon recommends...

Is it possible that the HFN test tracks are just too tough for a budget deck such as mine (particularly considering it's a 20 year old Planar 2 deck on a rather unstable equipment rack on a bouncy wooden floor...)? The blurb does warn that even the very best decks will have trouble playing the 4th track smoothly, so does that mean that my deck is just too humble to manage even the 2nd and 3rd tracks and that I'll need to upgrade (or at least get a wall shelf) before the 2nd and 3rd tracks will play smoothly?

Obviously I don't actually care about playing the test tracks smoothly, and if the deck plays most music with no trouble I'll be happy as it is (at least 'til I upgrade...) But I'm not sure about those 2nd and 3rd tracks and how important it is that my deck play them with no buzzing. If they're reasonable real-world tests then surely even my lowly deck should be able to handle them, and something is indeed wrong?

FYI the 1st track is a 300Hz tone at +12dB, the 2nd one is at +14dB, the 3rd one at +16dB, and the 4th one (the "torture" track) is +18dB.

Can anyone else with the HFN disc tell me how many of the four anti-skating tracks your deck will play smoothly?

Anyway, it's too late now to keep playing so I'll leave it till tomorrow, when I'll try playing some music with the setup as it is (set to 1.75g tracking force) and see how it sounds.

Dunc

 

how does music sound?

 

It's possible that you've damaged your test record. When you crank up the down force you change the attitude of the stylus in the groove and it clears up a bit.

Ensure the cartridge is aligned according to Rega's recommendation. Set the down force to the maximum recommended by the manufacturer. Set the bias on the dial to match. If it plays OK (and it will if your records are OK and your cartridge isn't damaged) then you can try tweaking down force and bias slightly each way by ear. Forget the test record.

Paul

 

Forget the test record is good advice. I've never used one in my life. Always better to set these things up with real records rather than torture tracks, it's not difficult to tell by ear if something is wrong.

-- Ian

 

Played a couple records this morning and it sounds lovely. I'm not sure but there could be a little crackly distortion at certain frequencies above a certain level that only seems apparent towards the inner part of the disc (and only in the left channel) but I'll need to try some more discs to know for sure. This would indicate an alignment problem, right? I.e. cartridge not quite aligned properly in the headshell? Anyway, I'll continue with the music for now.

Thanks again for all the advice.

Dunc