Broken stylus!

[struth]

start with180 degrees, subtract the first measured angle , add the second measured angle and divide by two.

[Pigmy Pony]

start with180 degrees, subtract the first measured angle , add the second measured angle and divide by two.

Like when fitting skirting boards round corners

[Barry]

Don’t mention SRA it sends some folks into apocalyptic rages!!

Why not? It is exactly the parameter Richard is trying to adjust.

VTA is a theoretical concept, which cannot be measured in practice. Whereas SRA can be measured directly; admittedly with difficulty and not without some risk of damage if care is not taken.

[Lawrence001]

Our cleaner has just left and I noticed that the Roksan Nima arm was halfway over the turntable and that the stylus on my AT33PTG/11 MC was broken. Trying to get hold of her...but can't at present. Perhaps a mishap with a duster?


Any suggestions for a compatible cartridge for the Nima?

I barely listen to LPs any more so would find it hard to justify an expensive replacement. Perhaps 'moving down' to a MM?

Eclectic music tastes (for a 76yr old!).

Thanks,

R

Did you ever get hold of your cleaner? I've always made it clear to ours not to touch the hifi I'd rather avoid any risk even if I have to dust it once a year myself when the wife says something.

[Bonky]

Did you ever get hold of your cleaner? I've always made it clear to ours not to touch the hifi I'd rather avoid any risk even if I have to dust it once a year myself when the wife says something.

Yes, very apologetic, but not sure if she was to blame (after all, without CTVC there's no evidence). (She uses a micro-duster on her hand - apparently). I will tell her not to go anywhere near the Hi-G again (!)

I am SO grateful to Steve for letting me use his Ortofon 2m Black... a revelation! I've still to play with the SRA (92 degrees) and VTA ( approx. 20-21 degrees), but so hard to measure. I think (as Barry and others have suggested), to do it by ear.

I have a plan (I have some good cameras (but not macro), to take pictures, print them and then using a protractor, to measure the angles. Mmm...we'll see...

Thanks everyone - an interesting journey, especially as I was thinking that CDs+ RME DAC, and/or AppleMusic+ RME+ Volumoi+ Wiim streamers, was/were the place to go.

Listening to a Tracey Chapman LP has convinced me/us otherwise.

Yet to use the combo with Classical Music.

Thanks,

R

[Chris]

Being an MM, wasn´t the secret of great sound from a 2m Black more to do with achieving a very low capacitance figure presented at the phono input ? Whereas my MM cartridge (A&RP77) looks for 450 pF which is apparently a highish figure and therefore easy to adjust to, usually by adding, with an Ortofon you usually need to find a way of reducing load capacitance to around 100pF.

[AJSki2fly]

Update: I'd like to publicly thank Steve (AKA Pigmy Pony) for his very kind offer of giving me an Ortofon 2M Black to replace my damaged AT 33PTG/2/MC. I had thought that the AT and the Roksan Nima arm were an extremely good match, but both my wife and I were very, very impressed with the sound of the 2M Black - and I think we prefer it. (Whether the AT was past its best -I don't know -perhaps!). I wonder if the arm (a unipivot) is better suited to MM rather than MC cartridges.

Has anyone any views?

Richard

Hi Richard, this might explain it, I think I have it right, if you take the Effective Mass of your arm and the weight of the AT 33PTG II and its Compliance you will find the resonant frequency to be a bit low at 5.28hz , whereas for the Ortofon is good at just over 7hz. Also the 20 degree tracking angle for the Ortofon may be easier to achieve than the 23 for the AT. Calculator http://mh-audio.nl/Calculators/RF.html

As long as it sounds good that is what matters.

[Pigmy Pony]

Hi Richard, this might explain it, I think I have it right, if you take the Effective Mass of your arm and the weight of the AT 33PTG II and its Compliance you will find the resonant frequency to be a bit low at 5.28hz , whereas for the Ortofon is good at just over 7hz. Also the 20 degree tracking angle for the Ortofon may be easier to achieve than the 23 for the AT. Calculator http://mh-audio.nl/Calculators/RF.html

As long as it sounds good that is what matters.

There you go Richard, you are now on Adrian's radar, and that's a good thing Has a lot of experience with cartridge set up, and really knows his stuff.

[AJSki2fly]

There you go Richard, you are now on Adrian's radar, and that's a good thing Has a lot of experience with cartridge set up, and really knows his stuff.

Well I would not say that, just made a lot of ,mistakes along the way, talked to a few who know better and read a bit.

On another note Richard the AT 33PTG II spec has two Compliance figures a static compliance of :-

Static Compliance 40 x 10-6 cm/dyne
Dynamic Compliance 10 x 10-6 cm/dyne (100 Hz)

The dynamic compliance is the deflection of the cantilever under a sine wave signal of a given frequency (100hz), however from what I have read this can be misleading, and purely using static is not the best. a good explanation if anyone is interested is here https://nirvanasound.com/wp-content/...arm%20Mark.pdf

Using the Static Compliance gives the 5.28hz, the dynamic one gives as below so may be fine.

Eff. Tonearm Mass : 15.3 g
Cartridge Mass : 6.9g
Fastener Mass : 0.5g (a guesstimate)
Compliance : 10 x 10-6 cm/Dyne

Tonearm Resonant Frequency = 10.56 Hz

But and it is a big BUT, as the cartridge ages and depending on how much it is used the compliance figure will change. I suppose for some cartridges the suspension may harden and thus stiffen and become less compliant, and for others the suspending will weaken becoming more compliant, I think that is correct. If the cartridge is new, is not that old and not used that much then it is likely safe to rely on the manufacturers figure, if not then as the article mentions using a good test record with frequency sweep tests and measuring the output on a computer or scope is probably the only way to be sure.

This is meant to be good - https://www.analogueseduction.net/te...st-record.html I use this one https://www.analogueseduction.net/te...st-record.html

[Bonky]

Thanks everyone. I do have an old (very old) HiFiNews test LP -but yet to use it with this combination; will do so later. I did raise the tail end of the arm 5mm or so and didn't like the sound and reverted to approx.8mm down. It rather enhance the bass so a little more experimentation is in order.