Stylus Suspension and Tonearm Balance Physics

[Penn42]

I'm finding the deeper into the hobby I get the greater level of attention I'm paying to adjustments and my system set up.

I'd been running a v15III on my 1219 for quite a while and was/am quite happy with it until I noticed the stylus suspension was shot. The cart body was not dragging on the record yet, but it was very very close at 1.25g.

It was an EVG elliptical that had been on there for quite a while. I don't have any complaints about its lifespan, but I think I might have helped its demise from cleaning the stylus too hard/much?

Until recently I had two tables set up, one fitted with a conical stylus for less nice records and my 1219 with this elliptical for quality records. In my new space I only have room for one table so I've taken to brushing the stylus after every older record played. All my records are vacuumed, but I still have a hard time going from a dollar bin find to a $45 Analogue Productions pressing, ya know?

Is it possible to ruin stylus suspension prematurely from over rushing it?

Once I noticed the suspension problem I decided it was a perfect time to try a different cart, so I put an m95 with kyowa elliptical on it. I've really been enjoying it, but my spare original sled was having intermittent connectivity issues, so I got a best audio sled, swapped to it, and added a metal spacer to bring the stylus tip to the upper limit of the height adjustment according to the dual alignment gauge. This set up was heavier and I had to move the counterweight way back to achieve balance when setting vtf.

What I've found is this heavier sled configuration does not track very well. I've had skips on records that didn't previously and the table is far more susceptible to footfalls near the audio rack. I'm wondering if the counterweight being so far back could be a contributing factor, perhaps making things more spring-y? I'll obviously continue experimenting here, but right thought I'd pay to hear other folks experiences.

 

[HamboneF18]

Suspensions can go bad. Nothing to do with stylus tip cleaning. I don’t know the age of your stylus; up to 2018, Jico was supplying styli to EVG. If later (newer) it’s a Swiss-made stylus. I’ve had several newer Swiss suspensions go bad.

 

[Nat]

Try a plastic or balsa spacer. I know nothing about Kyowa styli, but high compliance cartridges (and that may be a stretch with replacement styli, though the originals certainly were) don't do well in high mass arms. No idea how much mass your plate adds, but if skipping and footfalls are suddenly a problem, mass/compliance issues might be the cause. But don't assume that the new stylus is completely innocent.

 

[twiiii]

Then you guys wonder why to update cartridges or if new OEM stylus assemblies after 700 hours or 5 years.

 

[Hajidub]

If OP doesn't already own one, get a cheap digital stylus gauge. Tables of age tend to not be accurate when setting VTF.

 

[Nat]

I tend to rear up and disagree when people claim that older tables have inaccurate methods of setting tracking force - the most common method, the slip ring on the counterweight that spirals forward is pretty bullet proof - but the Dual coil spring system might go out of tolerance. I haven't had problems, but it might.
Because arms can be over slung and under slung and this can affect the scale's reading, get a digital scale with a platform close to record height. Just being digital means nothing - being accurate, and being used appropriately do matter.

 

[Hajidub]

I tend to rear up and disagree when people claim that older tables have inaccurate methods of setting tracking force - the most common method, the slip ring on the counterweight that spirals forward is pretty bullet proof - but the Dual coil spring system might go out of tolerance. I haven't had problems, but it might.
Because arms can be over slung and under slung and this can affect the scale's reading, get a digital scale with a platform close to record height. Just being digital means nothing - being accurate, and being used appropriately do matter.

Well, yeah, considering his turntable doesn't have a slip ring I guess I wasn't wrong in saying older tables aren't reliable. Own 2 Elac 50H's and 2 Dual's, all were off (sometimes up to a gram). Accurate, $11 gauge works just fine, they come with a 5g weight to ensure it's calibrated.

 

[HamboneF18]

If OP doesn't already own one, get a cheap digital stylus gauge. Tables of age tend to not be accurate when setting VTF.

I guess it depends on “age”. In that context, I don’t know if ‘64 is of “age”, or ‘70, or ‘71, or ‘77. But all of these tables I have are still very accurate, within 0.1 gram. As long as I balance with the arm parallel to the platter. I’ve never needed more accuracy than +/- 0.1 gram.

 

[Champco]

I'm finding the deeper into the hobby I get the greater level of attention I'm paying to adjustments and my system set up.

I'd been running a v15III on my 1219 for quite a while and was/am quite happy with it until I noticed the stylus suspension was shot. The cart body was not dragging on the record yet, but it was very very close at 1.25g.

It was an EVG elliptical that had been on there for quite a while. I don't have any complaints about its lifespan, but I think I might have helped its demise from cleaning the stylus too hard/much?

Until recently I had two tables set up, one fitted with a conical stylus for less nice records and my 1219 with this elliptical for quality records. In my new space I only have room for one table so I've taken to brushing the stylus after every older record played. All my records are vacuumed, but I still have a hard time going from a dollar bin find to a $45 Analogue Productions pressing, ya know?

Is it possible to ruin stylus suspension prematurely from over rushing it?

Once I noticed the suspension problem I decided it was a perfect time to try a different cart, so I put an m95 with kyowa elliptical on it. I've really been enjoying it, but my spare original sled was having intermittent connectivity issues, so I got a best audio sled, swapped to it, and added a metal spacer to bring the stylus tip to the upper limit of the height adjustment according to the dual alignment gauge. This set up was heavier and I had to move the counterweight way back to achieve balance when setting vtf.

What I've found is this heavier sled configuration does not track very well. I've had skips on records that didn't previously and the table is far more susceptible to footfalls near the audio rack. I'm wondering if the counterweight being so far back could be a contributing factor, perhaps making things more spring-y? I'll obviously continue experimenting here, but right thought I'd pay to hear other folks experiences.

I run a v15III on a Dual 601 for the last 40 years. Lately i bought two stylus. One was a NOS VN-35E.
One is a after market with a red colored VN-35e guard on it. There is no doubt in the stylus differences. It's apparant.
I like you play both used and new records and refuse to put the NOS which cost me over $400 onto a bunch of records, so I use the cheapo a lot and here is what I have noticed.
1 the cheapo range and sound is certainly lacking the performance of the NOS.
2 the cheapo does indeed skip on records which the NOS does not.
3 the tracking needs to be set between the two stylus to the point that the counter weight needs adjustment from a zero setting and then tracking is a 1/4 more then NOS to get close to the same performance.
4. The money well spent on the cheapo which hails from the Phoenix area has paid dividends in that as it plays it's performance has improved. I think it is the suspension. Just an observation.

 

[rothwellaudio]

I'm wondering if the counterweight being so far back could be a contributing factor, perhaps making things more spring-y?

Using a heavier headshell and moving the counterweight back to compensate for it will increase the arm's effective mass, so yes, it could be contributing factor.

 

[Penn42]

Then you all for the input. To answer a general line of inquiry: yes I have a scale. I did not use it on this set up because I know the table adjustment is pretty close. I'll bust it out to double check soon, but I expect the 1.5g I have it set at to be close to what it actually is.

Using a heavier headshell and moving the counterweight back to compensate for it will increase the arm's effective mass, so yes, it could be contributing factor.

That's basically what my laymen's thought process surmised, but I ultimately know very little about that stuff. Is there a resource that lays out tonearm mass/compliance/other physics-y stuff like that clearly and concisely?

 

[MitsuMan]

Then you all for the input. To answer a general line of inquiry: yes I have a scale. I did not use it on this set up because I know the table adjustment is pretty close. I'll bust it out to double check soon, but I expect the 1.5g I have it set at to be close to what it actually is.



That's basically what my laymen's thought process surmised, but I ultimately know very little about that stuff. Is there a resource that lays out tonearm mass/compliance/other physics-y stuff like that clearly and concisely?

Not really, although VinylEngine has some calculators to predict resonances, etc., but some of their calculators need data inputted that just isn't readily available for every TT tonearm out there.
Some TT manufacturers were very upfront and listed the effective mass of their tonearms. Most just give you an effective range of cartridge/headshell/mounting hardware weight that they suggest you stay within. This may or may not work depending on many factors like the dynamic compliance of the cartridge, etc. If you use an alignment protractor, keep the weight of the entire assembly within the manufacturers range for total weight of the headshell/cart combo you should be ok in most cases. Some might gasp, but I've used a non hardening modeling clay and made small dots of it and experimented with sticking the clay dots on the tonearm at various locations. Listen to the results and see if you hear an improvement or a degradation in SQ.

 

[rothwellaudio]

Is there a resource that lays out tonearm mass/compliance/other physics-y stuff like that clearly and concisely?

None in particular that I can think of. Whatever knowledge I have has been gleaned over the years from various sources. I'm sure a google search will turn up some interesting stuff.
However, I will say that "effective mass" is something of a misleading term and has more to do with inertia than mass alone. Consider two weights of, say, 5 grams each. They're on the ends of a rod of length 1 meter (which itself has no mass) which is pivoted in the middle. The weights balance each other, but they can be set into motion by applying a force. Now consider the same two weights on the ends of a rod 10 meters long. The weights on the longer rod have the same mass as the weights on the short rod, but they have more inertia, ie more effective mass. Think of it this way: if the rod is turning at 1 revolution per second the weights on the long rod are travelling faster than the weights on the short rod, so they have more inertia.

 

[Powertech]

Full checks I do personally on mounting a cartridge.
1. Overhang - Effective length of pivot to stylus.
2. Alignment using a protractor.
3. Azithmus using a small mirror.
4. VTF using a digital scale. I set the mass and then move the counterweight scale to match the reading.

For stylus cleaning I use a small sable paint brush always pulling the brush forwards past the stylus - not brushing against the canyilever and never brushing side to side. I do this gently before each play. Occasionally I dip the stylus in a cleaning gel.

 

[Nat]

I'm sure there are nuances to arm mass/cartridge compliance that I am not aware of, but most of it can be explained by high school level physics. If you actually want to account for specific masses at specific distances from the center of rotation, you might need to venture into AP physics, but if you just want a clear explanation of the fundamentals, you can't do much better than the original editions of Paul Hewitt's Conceptual Physics text, which ought to be easy to find - it was a great textbook for a really useful course - physics explained in normal language, not as a subset of math - so it was very successful. I thought the second edition was the best - after that they started improving and expanding it and putting all the math back in and it got out of hand. The first editions are clear, punchy, and eye opening. Read the whole thing - you will be much better informed about the world we live in.

 

[dlaloum]

There are a series of in depth physics threads on VinylEngine in particular, that I contributed to amongst others, about 10 years ago...

These go into detail around the interaction of cartridge suspension compliance with arm effective mass.

There are also on those forums, discussions as to how best to calculate the true effective mass of the arm.

The arm/suspension system, will have a resonant frequency (physics!) - and that resonant frequency will vary depending on those parameters - if it is in the "wrong" frequency zone - it will massively impact the stylus tracking ability - and a mistracking stylus is the absolute best way of destroying vinyl ...
It has to be the #1 cause of vinyl degradation! (and of course it impacts the sound produced as well...)

You can also do the reverse, and measure the arm/stylus resonant frequency, then using the calculated arm effective mass, you can calculate the compliance of the stylus - useful for non original styli where you suspect that the compliance is not as it should be!

Having said all that - once you know your arm effective mass - you can usually make a decent guess as to cartridge compliance by looking at its recommended VTF (assuming the manufacturer hasn't just copied and pasted from the original specs....) 1.25g or less is high compliance - best for an arm with effective mass below 10g (preferably around 7g or less) - around 1.5g is mid compliance ideal for arms around 11g/12g (many S-Arms) - around 2g is low compliance and best for heavy arms 16g+.

You can also widen an arms ability to match with differing compliance cartridges by fitting it with fluid damping (or the equivalent electro/magnetic versions) - options are available for standard Technics arms (KABUSA) and some others, lots of DIY solutions around as well... simple things like a tiny paddle made of plastic on a paper clip, dipped into a bottle top with oil in it, attached at the end of the arm.... can cause magical improvements to some otherwise intractable issues... - again physics.. particularly fluid mechanics...

Yes this is nerdsville central - fascinating stuff (for us nerds) - and in fact if you are interested and willing to dig into this area, performance levels similar to 5 figure turntables are achievable with thriftstore finds from the 80's.... - the high priced, jewelry level, outfits, sometimes have all these issues sorted for you....

 

[MitsuMan]

None in particular that I can think of. Whatever knowledge I have has been gleaned over the years from various sources. I'm sure a google search will turn up some interesting stuff.
However, I will say that "effective mass" is something of a misleading term and has more to do with inertia than mass alone. Consider two weights of, say, 5 grams each. They're on the ends of a rod of length 1 meter (which itself has no mass) which is pivoted in the middle. The weights balance each other, but they can be set into motion by applying a force. Now consider the same two weights on the ends of a rod 10 meters long. The weights on the longer rod have the same mass as the weights on the short rod, but they have more inertia, ie more effective mass. Think of it this way: if the rod is turning at 1 revolution per second the weights on the long rod are travelling faster than the weights on the short rod, so they have more inertia.

You're describing torque, i.e. force x distance equals some value in in-lbs or ft -lbs. They're dependent variables. If the weights are attached to the rod, and the rods are spinning at the same 1 RPM, the weights are spinning at the same speed regardless of the length of the rod. Don't confuse rotational velocity with linear velocity.

I wonder if you're thinking of radius of gyration. The farther away from the center of gravity, or in your analogy the balance center, a weight has more rotational energy (moment of inertia) than a weight that is rotating closer to the center or balance point.

 

[rothwellaudio]

...the weights are spinning at the same speed regardless of the length of the rod. Don't confuse rotational velocity with linear velocity.

No, I wasn't confusing angular velocity with linear velocity. I meant to say that the weights on the longer rod are moving with higher linear velocity and have more momentum.

 

[MitsuMan]

No, I wasn't confusing angular velocity with linear velocity. I meant to say that the weights on the longer rod are moving with higher linear velocity and have more momentum.

That's moment of inertia

 

[rothwellaudio]

That's moment of inertia

Exactly, which is what I was trying to explain in post #13.

However, I will say that "effective mass" is something of a misleading term and has more to do with inertia than mass alone.

Please feel free to explain to the OP what effective mass is and why moving the counterweight farther back increases it. Obviously I didn't do a very good job.