Upgrading From an AT LP120 (While Keeping VM540ML)

[v60sound]

Hi all!

I've been spinning on an AT LP-120 USB for maybe like 5 years (picked it up with a guitar center giftcard lol) and it has served me dutifully but I'm starting to get the upgraditus. I started noticing platter wobble which may or may not have been there the whole time (it's gone through several moves) and reading about tighter-bass, more controlled and dynamic decks has me wanting a bit more (plus I think I just deserve a nice table).

I have done the pre-amp mod which made a huge difference it made at least on my system. But the biggest upgrade by far has been upgrading the cartridge to a VM540ML, which I've come to truly love the sound of. I paid more for it than I did the TT (a sin I know) but it was still cheaper than a new TT and I figured I could just take it with me when I upgraded tables.

However now as I've been researching tables I'm realizing that just plopping any favorite cartridge onto any tone-arm comes with a dizzying array of compatibility issues.

My question is, are there a few main factors/specs I should be paying attention to when looking for a better table that might play nice with the VM540ML?

Or more specifically (shot in the dark) does anyone know if that sort of cartridge would play well with a Pro-Ject Carbon Debut Evo? This has seemed to be the table that caught my eye the most.

Thanks for any and all advice

 

[Tiver]

vinyl engine resonance calculator

I've read the tone arm mass is 6g. I will assume that the reference was effective mass. The cart is 6.2 grams. The mounting screws? I don't really know, but I have seen claims of 2g....kind of sounds high to me . I have a scale, sometime I will measure. As it's all at the end of the tone arm, I suppose actual mass is practically the same as effective mass. There are heavyweight screws some will use to increase mass at the cartridge end. Maybe you've seen the ones with biggish knob-like thumbscrews on top?

Anyway, the cart in question has a compliance of 10 @ 100hz, but we want to know what it is at 10hz, so we guesstimate 16 or 17 ?

Pluggin those values in....puts you resonance at 10 or 11. So in the zone. Addition weight from headshell screws could be an experiment that might lower your resonance to 9 or 10. Whether it would be audible in your system IDK.

These calculations really on good input. I have made a couple estimates so you should do your own research.

 

[v60sound]

Thanks! Yeah it might be time to get some reading done. Still quite foggy on the units here that are being used to measure Dynamic Compliance.

But from what I can grasp, there is an ideal level of resonance for a tone arm/cart combo that falls somewhere between 8-12Hz range? So assuming I can track down the specs on potential new tables and keep my units straight I can plug it into that link (Thank You!) and make sure the cart/tone-arm combo falls somewhere in the green zone?

Steering away from the numbers I'm starting to get the feeling that a Cartridge that works on a high-mass AT LP120 tonearm might not have the same synergy with a low mass carbon fiber tonearm.

 

[Tiver]

@v60sound There is some leeway in the matching. Like I said, falling in the zone is the target. Medium mass and medium compliance are a pretty broad spectrum. Finding the actual numbers isn't always a gimme. There is a tone arm data base on vinyl engine as well. Not all tone arms are represented, but it's always worth a look. Also you are at your own discretion for a conversion on compliance as there is apparently not a direct or linear conversion. I use 1.7 as a multiplier, but that's just some kind of approximation that may not always be real accurate.

The best I can describe my understanding would be a high compliance cart on too heavy an arm could cause the arm to "wobble" too easily like worn out shocks on a car but without enough spring to overcome the mass. Too low a compliance on a very light arm would cause the arm to bounce too easily as the cantilever is too stiff so not enough mass to compress the "spring". So in the first case the arm is overbearing the cantilever and in the second the cantilever is overbearing the arm. The further out of the zone one gets the more likely the mismatch will become physically impossible for the assembly to track the groove.

 

[v60sound]

That's a super helpful way of putting it! Thankya kindly. I was seeing the same thing about compliance conversion but that's re-assuring to hear another person say it. Fortunately nothing's broken so I've got all the time in the world to look for a a table that won't leave this cart useless. Big thanks for helping me start get a loose grasp on this stuff

 

[illini]

Thanks for any and all advice

Buy one of the latest Technics turntable models from an official dealer and install the VM540ML on that model. Sweetwater Sound, B&H Photo, etc. No affiliation...

 

[loudnoises]

Spending more on a stylus than the tables is plenty common, especially when you can find used tables for pennies.

I've a atn440mlb sitting on a $5 Yamaha right now.

 

[patient_ot]

Steering away from the numbers I'm starting to get the feeling that a Cartridge that works on a high-mass AT LP120 tonearm might not have the same synergy with a low mass carbon fiber tonearm.

The actual Western compliance of a 540ML is 23CU. Multipliers don't work with Japanese specs, so just ignore the Japanese specs entirely.

That's medium compliance by old-school standards but is on the higher end for today's carts.

The LP120 tonearm is on the lighter side of medium mass, it is not a high mass arm whatsoever. A high mass arm would be like 30g EM. Your LP120 arm is probably in the neighborhood of 12-15g EM.

Now, if you want to know the actual resonance of your cart/tonearm combo the best thing to do is measure it. It takes about 2 minutes using a record of ordinary music and software. You'll have to have a way to record the output of the turntable into the computer. Typically this would be a USB audio interface but the LP120 used to come with USB output built in. I do not know if that is still the case.