You may be confused by JVC’s cartridge designations, and they are confusing. The Z-1S is not the same thing as the Z-1. Here’s a rundown of some of JVC’s cartridge models.
Higher-end models:
X-1 – JVC’s best cartridge (in the 70’s), laminated core, beryllium cantilever, Shibata tip, samarium cobalt high energy magnet, very flat frequency response, 60kHz response, 1.7g tracking force – this could be used as a CD-4 cartridge, but unlike many other CD-4 cartridges, it had an exceptionally flat response within the audio band up to 20kHz, unlike many MM CD-4 cartridges from AT, Shure, Stanton etc. They obviously had some talented cartridge designers at JVC.
X-2 – later model (~1980), beryllium cantilever, Shibata MkII tip, 60kHz
http://wegavision.pytalhost.com/JVC/jvc80/jvc31.jpg ,
http://wegavision.pytalhost.com/JVC/jvc80/jvc37.jpg
Z-1 – second best to X1, same features, 50kHz, similar very flat frequency response, 1.7g tracking force.
Z-2E – later model, similar features to Z-1, but 0.3 x 0.7mil elliptical tip, without beryllium cantilever, 35kHz
Z-3ED – 30kHz, samarium cobalt magnet, laminated core, 0.3 x 0.7mil stylus, 1.7g. I'm pretty sure that the 'D' indicated it came fitted to a headshell, so there was probably also a Z-3E.
According to an aftermarket stylus catalogue I have, the Z-3E stylus interchanges with the Z-1S, Z-1E, Z-1EB and Z-2E, so can be used to upgrade those cartridges. However, it wasn’t shown as interchanging with the beryllium cantilever X1 or Z1 models.
Lower-level models:
Z-1S (also known as the MD-1025) – S = Spherical stylus (not Shibata), 0.5mil or 0.6mil*, aluminium cantilever, upper frequency response (probably -6dB or -10dB) 25kHz, tracking force 2g. This is very much a budget cartridge, which was bundled with many of their cheaper turntables, such as the QL-A2, their cheapest direct drive of the late-70’s. It was very much at the other end of JVC’s cartridge range from the Z1, despite the similar-sounding name.
Reviews I’ve seen of turntables fitted with this cartridge show it had quite a flat response for a budget cartridge, roughly 20Hz – 20kHz ±2.5dB, which is very good for a cheap cartridge. However, the 25dB at 1kHz separation specification was stretching the truth a bit – it was more like 22dB.
* Different JVC turntable manuals differ on the size of the spherical stylus size used for the Z-1S – either 0.5mil or 0.6mil. A 0.5mil spherical was known to be close to ‘bottoming out’ in the record groove, with disastrous results, so JVC may have later reverted to 0.6mil styli for most of their spherical-tip cartridges, as many companies did. For instance, Shure dropped their light-tracking N44-5 stylus (0.5mil) and replaced it with the N44G (0.6mil), both tracking at below 1.5g.
Z-1E (MD-1025E) – same features as Z-1S, but a slightly upgraded 0.3 x 0.7mil elliptical stylus, 2g tracking force. This didn’t seem to have been fitted to any turntables as standard equipment, so may just have been offered as an upgrade for the Z-1S.
Z-1EB (MD-1025EB) – 25kHz, 0.3 x 0.7mil elliptical, 1.75g. I suspect this had the same body as the Z-1S and Z1-E, but it had a better stylus tracking at a lower 1.75g, which could also be used to upgrade the Z-1E and Z-1S. It was bundled with some of their better turntables, such as the QL-Y3F and QL-Y5F – I have one which came on the used QL-Y3F I bought some years ago, and have been meaning to fit an SAS tip to it, but it’s not a priority at the moment.
Z-2E – 35kHz, 0.3 x 0.7mil elliptical, 1.7g. In the user manual it says that this was supplied complete with 5 tips when new, which would have been handy.
The samarium cobalt magnets used in the higher-end models mean higher magnetic energy from a smaller-sized magnet, so higher output and lower moving mass of the stylus/magnet/cantilever assembly can be obtained. Due to the use of the rare earth metal samarium, they generally weren’t used on budget cartridges, due to the high cost.
Did the Z-1S, Z-1E, Z-1EB or Z-2E have laminated cores? Well, I suspect that if they had, JVC would have mentioned it. Frequency response plots for the Z-1S and Z-1EB clearly show the midrange to high frequency dip characteristic of MM cartridges which have solid core pole pieces, so I doubt that they do have laminated cores.
Some later ‘JVC’ cartridges were just OEM re-badged Audio-Technica ones, but you can always pick them because they say in the specs they have dual magnets. None of the ones listed above are AT-manufactured – they’re all JVC designs.
So the MD-1025 cartridges (Z-1S, Z-1E and Z-1EB) are quite different from the Z-1 cartridge, which was much superior with its Shibata tip, beryllium cantilever and laminated core. Whether the styli interchange or not, nobody mentions in their catalogues and websites, although the body of the Z-1 looks very similar to that of the Z-1E on the Japan Audio Heritage website, and it mentions that it inherits the 'body structure', which probably just means the exterior.
So my guess is that the Z-1 and Z-1S/Z-1E/Z-1EB styli interchange, but because I doubt that the cheaper models have the laminated core, I don't think that fitting the Z-1 stylus to the Z-1S would upgrade it to Z-1 performance levels - the frequency response would still have a dip caused by its solid core.
I've currently a Jico Shibata on the Z1-S which is okaish and as good as any MM I've ever heard (though I still prefer the Empire 4000 D/I despite it losing in terms of detail and bass, as well as both my Grace F9 and F8)
The question is, would a SAS significantly improve on the Z1-S?
Yes, the SAS tip is quite superior to a Shibata tip:
- 6 x 50 μm - Shibata ‘small’ design
- 6 x 75 μm - Shibata ’large’ design
- Microridge 1 (on Shure cartridges, made and designed by Namiki) 0.15 x 3 mil / 3.8 x 75 μm
- Microridge 2 (Namiki) 2.5 x 75 μm
- Micro Line (AT) 2.5 x 75 μm
- SAS (Jico) 2.5 x 75 μm
You can see that the MR2/ML/SAS tip, which is almost certainly the same tip made by Namiki Jewel, but renamed by Jico and AT for their own marketing purposes, is less than half the thickness of both Shibata designs, and with similar or increased large radius size, depending on the Shibata variant. The Shibata was the first extended line contact tip (1972), and was co-designed by Namiki with JVC, and manufactured by them for JVC. The Microridge 1 (1983) was one of the next generation tips, much improved from the Shibata, and the MR2 was a later improvement to that shape – it’s the thinnest current shape.
There are other shapes, but that answers your question – the SAS (or ML/MR2) is the thinnest current stylus, so should trace high frequencies and inner grooves the best, with the lowest distortion. To quote Soundsmith, “In pure sonic terms on pristine vinyl a top notch elliptical can do as well as all but the very best Line Contact / Shibata styli, but will ultimately be surpassed by the better MicroLine (i.e. SAS) styli.”
The other thing about the Neo/SAS is that it has a more rigid and lighter sapphire cantilever compared to the Jico Shibata’s aluminium alloy cantilever, so will have improved tracking.
On another note, Jico don't seem to make a stylus for the X2. Will the X1 shibata stylus fit the X2, and would it compete with a Z1-S that has a SAS?
Opinions and guestimates please
I don’t know if the X1 stylus fits the X2, but this website seems to indicate it does
https://shop.mantra-audio.co.uk/acatalog/JVC_stylus.html , and there's also an Australian seller on eBay selling a horrible conical stylus for them both. One difference between the X1 and X2 was that the X2 had a Shibata Mk2 tip, which was slightly improved over the Shibata Mk1, although JVC gave no info about the sizes of the radii. It also had a heavier body than the X1.
Given that the X2 body has a laminated core (I think), it should provide a flatter frequency response than a Z-1S body with a similar stylus.