[dlaloum]

Hi Folks

so my JVC is running very sweetly..... and I am thinking about messing with cartridges...

Specifically I have an ADC cartridge - unkown model... no markings - suspected of possibly being a Super XLM due to the very low measured inductance (258mH)... I also have a virgin SuperXLM stylus (purchased seperately)... compliance 40 (!!!)

I know that these would go well with my Revox Linatrack 4g tonearm - a perfect match really.... but the Linatrack is currently set up for p-mount and I am loath to change this right now.

By my calculations a compliance of 40 in a tonearm with an estimated total mass (arm/headshell/cartridge/counterweight) of 20g adds up to resonant frequency of 5.6Hz - that's pretty much a bullseye in the BAD zone.

I cannot make the arm lighter (I have already made it as light as possible using light headshells - the counterweight won't screw in any closer to the pivot!).

My concern is how will this theoretical mismatch work out given the Servo Damping?

What are people's experiences with very high compliance cartridges in these types of arms ? (JVC/Denon) - preferably the slightly heavier S type versions like mine (QL-Y5F)...

These vintage styli also had a period reputation of collapsing suspension when used with overweight tonearms.... (it ain't obese..... I swear.... been on a diet and everything!)

Am I pushing things too far in thinking of pairing these two?

Thanks & Bye for now

David

[neobop]

My concern is how will this theoretical mismatch work out given the Servo Damping?

What are people's experiences with very high compliance cartridges in these types of arms ? (JVC/Denon) - preferably the slightly heavier S type versions like mine (QL-Y5F)...

These vintage styli also had a period reputation of collapsing suspension when used with overweight tonearms.... (it ain't obese..... I swear.... been on a diet and everything!)

Am I pushing things too far in thinking of pairing these two?

Thanks & Bye for now

David

I think your concerns are well founded. You might be able to make it work with the damping, but it won't sound nearly as good as it would in a light arm. It will probably sound sluggish, something the ADC, or any cart, can ill afford. Seems to me the strength of the XLM is in it's smooth extended response and musicality, not transient response. Not that it's particularly slow. I've also read about sagging suspensions in these.

I don't have one of those JVCs, but I doubt if servo damping can change the res F of the arm/cart. It probably damps the amplitude of the res, like the fluid damper in a Jelco 750D (eff mass 20g). IMO you'll get best results with a cart that works good with the arm, wo/damping. The AT-7V should work just fine. Also the Benz MCs would be great. People with 750s say the can use carts with a dynamic cu of around 20, & damping, with good results. I think 40 is pushing it, and would be foolhardy to even try it if the arm is that heavy. Those styli are hard to come by. It would probably be drooping in less than 100 hrs. Save it for the Revox
neo

[dlaloum]

    waaah, stomp, rage  tantrum

But I wanted to try the cartridge NOW!!!

Sigh....

Have to say my N97xE-SAS has been working well - with a compliance of 22 .... but it is assisted by both the arm damping and the Shure damping brush....

Still - would like to hear from people who have experience with either fluid or servo damped arms and high compliance carts...

I also have a Benz MC1HO - although being a late 80's MC I have no specs for it - but based on other Benz carts its probably around 15... a perfect match.... and it is one of the carts I am comparing.

Still - I was keen to hear this legendary combination - but it may have to wait.

bye for now

David

[dlaloum]

ChairGuy - noted some postings from you (couple of years back) with regards to tonearm damping....

Do you have any input as to the relationship between "Q" on the JVC arms and Cartridge compliance?

thanks

David

[TheChairGuy]

ChairGuy - noted some postings from you (couple of years back) with regards to tonearm damping....

Do you have any input as to the relationship between "Q" on the JVC arms and Cartridge compliance?

thanks

David

Hi David,

What relationship input are you looking for exactly?  My experience of various cartridges on the Q-damped arms? Ok.

There really is 2 Q-damping systems from JVC.  An earlier, internal oil damped arm (the QL-F6 with 9" oil damping is the one I have...and there were others circa 1978-1979) and the later electronic Q-damped arms (which I think began in 1980 and may have ended in 1985 with the introduction of the QL-Y66F)

I think most if not all of the electronic Q-damped arms were longer than 9"...perhaps 9.5" and longer, so it's a bit difficult to assess the affect of the electronic Q-damping on the overall sonics as the arm length has so much to do with tracking prowess I've found.

Every cartridge tried on the oil damped F6 sounds good....as it's a winning deck (after adding 7lbs of plasticlay to the interior and carefully setting up good supports and feet underneath).

Those same cartridges on the electronic damped Y66F sound better.....but is it a function of the 10" arm, the (more refined?) electronic Q damp system, heavier 13" platter, partially magnetic levitated platter, ?, ?, ? 

So many variables to wick away to get definitive answers on the affect of the damping system

Among the cartridges in my stable or been tried on one or both the past several years are:

Pickering XLZ-7500s (low output moving magnet)
Ortofon X5-MC - (high output moving coil)
ADC XLM MkIII Improved with Astrion tip (hi output moving iron as you know)
Denon DL-160vdH (hi output moving coil)
Denon DL-S1 (top of the Denon line low output moving coil)

...there's probably a couple others that have been tried on the tables.  I own about 12 cartridges today of various makes, compliances, outputs, etc.

Seems to me that variable Q-damping has the affect of making all cartridges a better fit with tables thus equipped.  Tho I have to give some thought to what neobop is saying about cartridges not needing damping to sound good may be best of all. 

I'm not sure I'm in agreement with that...but, it makes me want to give serious pause and further reflection on it. 

Above all, try any cartridge on it.  If it sounds good to you, then it is good  Seems to me that's that this hobby should be about...personal and innate satisfaction rather than group think on what does or doesn't sound 'good' 

Ciao, John

[neobop]

I don't know about the QL-Y5F, but some of the more sophisticated versions of these Q-damped tables came with both heavier S shaped arm tubes and lighter, straight arm tubes. Why do you think that is, aesthetics?

The fact of the matter is, arm mass has implications other than res F. On the one hand the arm has to maintain the cart in a stable position for accurate tracking. On the other hand the cart has to drag the mass of the arm around as it negotiates the grooves. I stand by my earlier post. Your table as it is now, requires a stiffer suspension cart for optimum performance. The ADC will really sing in a light arm. Ever see an ADC arm?

My Sony X-50 has a 20g undamped arm. If I reduce the eff mass by substituting a headshell that's 4.5g lighter, I can get certain med cu carts to work. The most successful of these was a AT-15SS. The lighter weight 440ML sounds like crap on there. The Ortofon M20FL Super sounds sluggish, and it sounds good on an 8g arm. Same for the 440. But a Benz MC20H was really nice with the stock headshell. I didn't even consider trying a Stanton 980, which I really like.

What's with the P-mount on the Revox, something special? Unless you get the straight arm tube, go for a good arm/cart match. Q damping isn't some magic bullet for sound quality.
neo

[TheChairGuy]

I don't know about the QL-Y5F, but some of the more sophisticated versions of these Q-damped tables came with both heavier S shaped arm tubes and lighter, straight arm tubes. Why do you think that is, aesthetics?

Yeah, good point(s) there, too.

The oil damped F6 has a 9" arm....that's S-shaped.

My Y66F uses more sophisticated electronic Q-damping and has a 10" arm...that is a straight pipe.  New from the factory this model came with both an S and straight arm...but I most often see only tables with the straight (we assume, lighter) arm on them. My two Y66F's had only straight pipes on them so I cannot compare.

From my manual, with the exception of US, Canada, UK and West Germany, the Y66F was packaged WITH a cartridge pre-mounted on the straight arm.

It was a JVC MC-200E, hi output (2.3mV) moving coil.  It weighed 4.3 grams, had a nude elliptical stylus with recommended tracking force of 1.75 gram (+ or - 0.25 gram).

The (dynamic) compliance is listed as 8 x 10 (-6) cm/dyne

For the Y66F, the applicable cartridge weight for both arms were:

Straight Pipe: 4.5 - 10.5 gram (or 17.5 gram with subweight used)

S-arm: 8 - 14 gram (or 21 gram with subweight used)

So, now the theory seems to be all weirded out a little.  JVC mates a low compliance moving coil on their lightest arm offered for this model 

John

[neobop]

4.3g is a very light plastic cart. The OEM was probably AT. I don't think JVC manufactured carts and it was commonplace for companies like AT or Satin to supply them. The weight, 4.3g suggests AT, who made lots of carts for companies like Pioneer and others. In any case the compliance is probably at 100Hz. This is almost a certainty. Other Japanese companies like Nagaoka and Denon also state dynamic cu at 100Hz.

Many people think that if cu is stated at 100Hz, then 10Hz cu is around double that. It ain't necessarily so. I just happen to have the spec sheet for a Pioneer PC-401MC. This is a HOMC with replaceable stylus, made by AT. I wish it was still working cause it was nice sounding.
Dynamic cu = 12 @ 100Hz
Static cu = 16
VTF = 2.0g + - .3
weight 3.1g

Static cu is a measure of springiness - straight up. This cart worked good in my 20g Sony. The static cu is a more telling figure than 100Hz dynamic. There's no way that 10Hz dynamic is 24cu.  Static could actually be higher in the JVC branded cart. I know, it's a mystery wrapped in an enigma.

The cartridge weight range for the arm is only what weight range you can use, and has little to do with eff mass. I was assuming that the S arm is 18g or more, and the straight one is considerably less. If the damping can be defeated, you could ballpark mass with a known cart and a test record. You can probably do it even if the damping can't be completely turned off.
neo
 

[dlaloum]

I read a series of thread on VE with regards to working out Tonearm mass....

From which I built a quickie spreadsheet (LuckyDog on VE also published a rather more polished SS).... I weigh the counterweight, weigh the tonearm without counterweight, weigh headshell (and cartridge if working out total eff. mass.) - measure counterweight distance and plug in the effective length of the arm.... and out comes my estimate of eff. mass.

For the JVC QL-Y5F I've worked out that the lightest Headshell/Fixings/cartridge combination I can balance is 13.5g... using that, the two SS models come up with an effective system mass of 17.2g and 19.1g ... so I use 18g as my estimate.
All of which would have been unnecessary if there were published specs for effective tonearm mass! - I also found out that I cannot lighten the arm by reducing headshell weight - as I have reached the inward limit of counterweight adjustment. (I am working on finding a lighter CW...)

The model seems to be quite effective - and useful when trying out combos of differing cart weight/headshell weight etc... trying to work through what might or might not have good synergy.

My own estimated conversions for compliance are:
Japanese 100Hz Dynamic compliance  x 1.75 =(est) 10Hz Dynamic
US Static x 0.5 = (est) 10Hz Dynamic
I checked this estimate method - and where I have both 100Hz Dynamic and Static figures the conversion factors end up pretty close to each other....

This is of course focused on vertical compliance - and there is also lateral/horizontal compliance... which is usually the same - but not infrequently differs (usually by no more than 10%)

I am in the process of trying out a range of cartridges, cables, loadings... sort of developing an understanding of the whole "system" - which is why I fitted a P-Mount to the Revox... if I need to chop and change, spending well over an hour mounting a cartridge is a serious pain...  Which was one of my drivers in getting the JVC.
With its damping it is as widely compatible as an arm is likely to get.... a perfect Sandbox for my purpose....

But I don't want to damage a cartridge's suspension either...

The original JVC cartridge wasn't all that low in compliance -dynamic was listed at 8 - but it is a Japanese manufacturer - so assuming it is based on 100Hz .... using my rule of thumb (x1.75) takes it to 14 (at 10Hz)... not "High" compliance.... but spot on for that arm.... at 18g the Resonant frequency is around 10Hz....

And yes I agree with neobop - the damping will reduce the influence of the resonance by spreading it over a wide range of frequencies (and absorbing some of it) - but we are definitely better off not having a resonance to deal with in the first place.... (or having a resonance in a place where it does no harm) - and reducing the damping... but not I think eliminate damping... underdamped is bad - as is overdamped.
That is my gut feel anyway - when I get around to it, I will do some tests and measurements. (which will require a single cartridge with a series of styli having different compliance.... so not right now)


bye for now

David

[neobop]

David,
Seems sensible, but I question the 100Hz conversion. I really think results will be coincidental.
"My own estimated conversions for compliance are:
Japanese 100Hz Dynamic compliance  x 1.75 =(est) 10Hz Dynamic
US Static x 0.5 = (est) 10Hz Dynamic
I checked this estimate method - and where I have both 100Hz Dynamic and Static figures the conversion factors end up pretty close to each other...."

There is no method for converting 100Hz to 10Hz cu. I'm not sure what US Static is, a typo? Maybe 1/2 static = 10Hz dynamic?
The specs for the 401MC I posted are from the spec sheet. Lets see if they work.
Dynamic cu @ 100Hz is 12. OK, x 1.75 = 21cu @10Hz?
Static cu = 16     Then est 10Hz dynamic is 8?

Maybe I misunderstood what you meant with the US static, but it really doesn't matter. I think you can see that it just doesn't work. Both 21cu and 8 cu don't seem plausible.

Thanks for posting Luckydog's est arm mass thing. It's interesting. What if the headshell is not removable? I still can't access VE. I think it has something to do with my server and new VE filters. It's really only their data banks I want to use.

I'm not sure if the Q damping spreads resonance over a wider range of frequencies, or if it damps the amplitude of the resonance. Not sure how spreading it would work. Maybe John has more info on that. I can't help but think that it's better with most carts, if no additional damping is required. Then, if just the amplitude is moderately damped, it shouldn't interfere with cart performance. Some people look at additional damping as a plus. I see it as a band aid. I think it wouldn't hurt to try the ADC. But it's not a good match by any stretch of the imagination. Seeing how your reluctant to spend an hour setting up a cart, then another hour removing it and setting up another..... Well, good luck with it. Let us know how it works out.
Regards,
neo

[dlaloum]

The process with the Revox involves disconnecting the TT, removing platter, bolting the suspension down, turning it upside down on appropriate supports (usually books) -with the Linear tonearm swung out at 90 degrees so it sticks out to the side...

Then you remove/screw in the new cartridge.... BUT - first you have to precisely measure the new cartridge and get the precise shims to ensure cartridge mounting height is precise to within +/-1mm. (This is made more difficult due to variable suspension give - it is hard to predict how much to allow for the suspension) - adjust cartridge alignment using Revox alignment gauge (this is the easy bit).

Then Reverse the process (turn it right way up, unbolt suspension etc...) so you can now  swing the arm over the platter well where you put the carefully positioned digital stylus weight scale (also carefully measured so it is precisely at the height of the surface of an LP) - lower the cartridge and check / adjust lowering distance and VTF. There are a couple of check points at this stage that can tell you whether you got the shimming right (tonearm lowering sensor PCB should be 50% exposed when in playing position if right - if more or less is exposed - readjust the shimming) - most likely there will be at least one shimming readjustment (rebolt, disconnect power, turn upside down etc...)

This is the simple version of course - there is also a way of aligning the tonearm for correct tangential positioning - makes all the above look like childs play.

Yes it is a PITA ... but also it works really well once done, and sounds great.... so while I am experimenting / playing with cartridge / styli / cables / phono stages etc... I decided to fit it with a p-mount adapter.... once aligned and adjusted I can pretty much swap them in and out within 20s.... and I have a few very nice P-Mounts to play with.
I can also take the same cartridges and plug them into a preprepared p-mount adapter fitted headshell for direct comparisons on the JVC...

But getting a cartridge mounted, aligned and running in the JVC can be done in somewhere between 1/4 and 1/10th the time for the same job in the Revox....

With regards to compliance... yes by US Static, I meant the Static Compliance specification which is frequently used in the US - apparently less so in Europe, and seldom in Japan... and your assumption was correct - and the correlation appears not to work....

Although strangely when I have done this conversion for AT cartridges it seems consistently close (for the 4 or 5 where I did this).

With regards to the tonearm mass calculator - you can also treat the headshell as part of the arm - I think it marginally reduces accuracy - there is a more complex model (which I think is suspect) which also takes into account center of gravity and length of headshell....

I am still in two minds about trying the SuperXLM on the JVC... might have to wait for when the Revox is available...

bye  for now

David

[e.man]

Thanks for starting this thread David.  Exactly what i was wondering about.

I wasn't convinced my Stanton 680(MI)/Shibata was giving enough 'snap' (speed?) on the JVC QL-y5f so was looking to try something else
.
I managed to buy a Ortofon X5-MC - (high output moving coil) for a good price and it sounds much better.  A bit too much topend perhaps which needed attention.  Compliance on this is listed as 14 I think (I don't know how it's effected by the 10Hz/100Hz business).
Perhaps not fair to compare a MI w/ a MC but there it is.

[neobop]

Since this thread was going earlier, I think I have a slightly better understanding of 100Hz compliance, or its 10Hz equivalent. First off, 2 clues will give you a good idea of the range you're looking at. The first is static cu, if you have that spec. Static cu is a measure of, well, a cart not in motion. That figure is always higher than dynamic. How much higher depends on many factors, but to guesstimate - For a cart with 100Hz dynamic of 10cu, static will be around 30, or 3 to 3.5 X 100Hz dynamic. There are too many other factors to ballpark that closer. The other clue is VTF. 2.5g is lower cu than 1.5g, commonsense.

The other thing is, I don't think that 100Hz cu is actually a measure of compliance, at least not in the same way as 10Hz. That's reason why there is no reliable conversion. An AT like the 95E has a 100Hz cu of 6. It's 10Hz cu is around 15. A DL-103 has a 100Hz cu of 5 or 6 and it seems considerably stiffer. To find out what range of arm mass a particular cart likes, read or ask.

Also, you're more likely to get away with using a higher cu cart on an arm that's a little too heavy, than a low cu cart on a light arm. I wouldn't put a 40 or 50cu (10Hz) cart on a heavy arm, but it could work. I would recommend against putting that 103 on a Black Widow.
neo

[e.man]

I have just changed my Ortofon X5 cart from the heavy 1970s ? Sony headshell it came with onto a current much lighter Ortofon headshell. 

As I recall on another thread David (dlaloum) was spending some time getting his headshells lighter.  Just wondering if this was in pursuit of some general improvement and what that might be.

Also if ChairGuy sees this I note upthread you have Ortofon X5 and Denon DL160.  I'm having trouble taming the top on the X5 so might try Denon DL110/103 later.  What sort of difference do you hear X5 to Denon ? 
Or even tips on using the X5 on this TT.  Yes I have the tail down and the Q damping up.

[dlaloum]

Hi e.Man,

my search for lightness was related to my attempts to optimise for my high compliance cartridges (at the time I was focusing on the OM30).

I did manage to drop around 5g with noticeable impact on the resonant frequency (it rose from down below 7Hz up to around 9Hz..... from memory)

It involved both lighter headshells and lighter counterweights....

With a compliance of 13cu the X5 would work perfectly without messing with the arm weight on a standard S-arm.

Changing headshells could still be done and WOULD impact on the vibrational environment - so there may be improvements to be found there - would also be worthwhile calculating what mass headshell would provide the optimum (or within the optimum range) mass - so that you don't meander too far from that value in your search for headshells.

The other tricks with headshells include the Van Alstine plasticine tweaks (a dot of plasticine under the wire join at the back of the headshell - provides optimal damping between 300Hz-3kHz and lesser damping for a much wider F range)

Headshells are available in various woods, carbon fibre, different plastics, aluminium, magnesium - and then there are various shapes and construction methods. - every headshell is a different vibrational environment... also how the headshell connects / interfaces to both cartridge at one end and arm at the other can change things too.... (the same headshell will give one result when used with its spacer/washer and another result when used without - which of the two gives the better result may depend on the cartridge, plinth, or even table isolation).


The improvement I was seeking: - reduce the amplitude and raise the frequency of the low F arm/cartridge resonance ....

Although my arm has servo damping - that is a means of reducing resonances that are in existence - and getting rid of them at the source is better again - obviously they are never totally gone, so the arm damping then mops up the remains - but the end result is better.
Improvements are not only in the LF range, as all the harmonics of that resonance are also reduced in amplitude substantially, and the intermodulations of both the fundamental resonance and its harmonics are also reduced.

And I am not even discussing improvements in tracking - which are not relevant in my case as the servo arm basically takes care of that, so the tracking differences are negligible, but the sound differences are still there.

I think a lot of people get good sound from a cartridge and stop there - never realising the potential of their cartridge.... and this applies to arm mass compatibility, damping issues, as well as proper loading....

bye for now

David

[e.man]

With a compliance of 13cu the X5 would work perfectly without messing with the arm weight on a standard S-arm.

That's what I was hoping.

I have no desire to go about 'headshell hunting'.  I just got the Ortofon headshell to go with the Ortofon Cart.  The colouring matches the servo gear at the back of the tonearm too.

The other tricks with headshells include the Van Alstine plasticine tweaks (a dot of plasticine under the wire join at the back of the headshell - provides optimal damping between 300Hz-3kHz and lesser damping for a much wider F range)

Isn't "under the wire join at the back of the headshell" vertical ?  Wouldn't Plasticine be in danger of falling off ?  I don't have any Plasticine anyway.  Would Blu-Tack be OK ?  What sort of diameter dot is that ?

(the same headshell will give one result when used with its spacer/washer and another result when used without - which of the two gives the better result may depend on the cartridge, plinth, or even table isolation).

Thanks for mentioning this.  I found I had 2 spacer/washers and put them on, lifting the cart from the headshell.  It gave more presence,punch and detail.

Am still having some trouble in the sibilant range tho so have pushed the overhang right out which helped a bit.  Am I puting anything in danger by doing that. Just trying to get the sound I want. 

[dlaloum]

Plasticine is also called "non hardening modelling clay" - and there were some scientific studies that analysed its effectiveness as a damper...

Blue Tack is a bit different, it is a harder material inherently and it does harden over time.
A number of people have used it with success in various ways... (headshell's, between stylus and cartridge ... etc...) - I am wary of it as it hardens over time - I don't want my tweaks changing on me in that way!

Plasticine or its local equivalent will be found in any local toy store.... and costs almost nothing.
It molds to take the shape of what it is applied to, and then tends to stick (not very strongly, so it can be removed if you want to).

A dot of about 1/3rd to 1/4 of an inch diameter is sufficient, you put the dot under the wires in the headshell, wedging it in between the vertical back of the headshell and the horizontal top of the headshell - if you can put a touch more so it makes contacts with the sides of the headshell as well that can be a good thing.
The more constrained surfaces it contacts the more effective it will be...

Another trick with plasticine, is to take a similar size dot... and gently tap the tonearm, until you find the point at which the tap resonates most loudly - put the dot at that point.... damping HF arm resonances.... a substantial improvement for the cost of a couple of cents worth of modelling clay!

With regards to overhang....

The overhang is part of adjusting the tracking alignment of your arm/cartridge.

Misalignment of the arm/cartridge is (one of ) the most common cause of sibilance....

You have two choices - check the manufacturers specifications and align the cartridge accordingly (this will be a measurement from the start of the headshell washer to the stylus location... standard technics measure is 52mm, my JVC uses 48mm) - position your cartridge fore-aft in the headshell to get this measurement "spot on".

Then make sure that your cartridge is precisely parallel to the sides of the headshell (ie: the "line" of the arm).

The end result will in most cases (with Japanese turntables) be a "stephenson" alignment... - if you have the patience and time, you can in most cases get an even better result using a baerwald or lofgren alignment.

Pick up a printable protractor for aligning your TT at : http://www.vinylengine.com/cartridge-alignment-protractors.shtml

Achieving a non OEM alignment will require setting the cartridge to a different fore-aft position and twisting in in the headshell (it will no longer be parallel to the "line" of the arm).

This can also have an impact on sibilance....

Personally I have chosen to stay with the OEM setup for simpicities sake - as I am currently messing about with a lot of different cartridges.... once I settle on a long term cartridge, I will then look at the fine tuning of the cartridge alignment using baerwald or lofgren.....

bye for now

David

P.S. yes I have a dot of plasticine on my tonearm - and I have a dot of plasticine in SOME of my headshells.... 

[e.man]

You have two choices - check the manufacturers specifications and align the cartridge accordingly (this will be a measurement from the start of the headshell washer to the stylus location... standard technics measure is 52mm, my JVC uses 48mm) - position your cartridge fore-aft in the headshell to get this measurement "spot on".

Then make sure that your cartridge is precisely parallel to the sides of the headshell (ie: the "line" of the arm).

The end result will in most cases (with Japanese turntables) be a "stephenson" alignment... - if you have the patience and time, you can in most cases get an even better result using a baerwald or lofgren alignment.

Pick up a printable protractor for aligning your TT at : http://www.vinylengine.com/cartridge-alignment-protractors.shtml
..
Achieving a non OEM alignment will require setting the cartridge to a different fore-aft position and twisting in in the headshell (it will no longer be parallel to the "line" of the arm).

I have been starting cartridge overhang on my JVC at 48mm.  This actually seems to get things set up on the 2 point Ortofon protractor I have like this one shown here http://www.mds975.co.uk/Content/vinyl07.html.  This article says it's a Baerwald alignment.

After extending the overhang I noticed it did not sit straight at the 2 points marked at 66mm and 121mm so I was thinking of giving the cart a bit of an angle in the headshell.  So thanks for answering that before I even asked it , hahaha.
After this the result (after very little testing) seems to have reduced the sibilant somewhat to a more residual amount.

It's hard to see what else I can do mechanically so I'll look out for some plasticine.

[dlaloum]

Felix is using the Shure two point protractor in that article - which apparently is set up for Baerwald...

I honestly don't know what the Ortofon one is set up for.... and I thought (can't recall why right now) that the JVC's like most Japanese tables were OEM setup for Stephenson.... (according to rumours that is/was due to Japanese records using longer run times and having the inside tracks closer to the centre....)

At some point I really should check the OEM JVC alignment and work out whether it matches one of the standard ones....

Glad to hear the alignment helped with the sibilance 

bye for now

David

[e.man]

All sorted.  Sounding fine.  Reset to 48mm.  Answer was to play better records 
This cart brings out what's on the record so much more than I was used to, which includes hearing the worn out ones a lot more too.

Added some 'modelling clay'.  It really added some 'thud'.  No sub required.