Tonearm height confusion

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JoshK

Tonearm height confusion
« on: 11 Nov 2018, 10:06 pm »
I am attempting to setup my TT after years of it laying idle, actually more than a decade. Thing is, my TT isn't one an off the shelf plug and play type. My TT is a custom Teres Audio (not even a particular model, but most similar to the Teres 200 series such as the 265).

The thing I am struggling the most with is the height from the top of the armboard to the top of the platter. Is there any standards? Are their arms that have different heights? My platter sits 2 7/8" from the plinth, while my armboard is 1.5" from the plinth (both measured at top). Thus there is a 1 3/8" differential. For my Rega 300, I have to shim the hell out of it and even still I am not sure when cart is mounted it will clear.

Can anyone point me to any guides that explain this portion of the setup? I found a lot of other info not related on setup already.

toocool4

Re: Tonearm height confusion
« Reply #1 on: 11 Nov 2018, 10:20 pm »
Sounds like you need to get yourself a tonearm that allows you to adjust the tonearm height more easily, the Rega’s are not known for that or you need to have a new armboard made for that turntable and arm combo.

On my Acoustic Solid One to One I am using a Dynavector DV 507MKII, makes for easy arm height adjustment which is convenient for getting the correct SRA angle too.

S Clark

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Re: Tonearm height confusion
« Reply #2 on: 11 Nov 2018, 10:24 pm »
Some measure stylus angle with microscopes...  but the quick and dirty is simple.  Put the stylus on a record and put a notecard behind the tonearm.  Look at the lines on the notecard and compare to the tonearm.  If they are parallel, you're all set.  If not, adjust accordingly, raising or lowering the tonearm or shimming the cartridge. 

JoshK

Re: Tonearm height confusion
« Reply #3 on: 11 Nov 2018, 10:35 pm »
Thanks, but neither of you unfortunately gave me any new info.   What I really want to know is what is the standard differential between armboard height and platter height.  I can't imagine there is a lot of variation in this, but the question seems to be answered no-where that I can find.   If there were a lot of variation then most arms wouldn't work on most different tables.  However, I had to shim my Rega over 1" and I still won't clear.  This isn't simple VTA adjustment or minor adjustment, this is big adjustment.

My arm, bearing and platter were all factory from a 260 Table, but my plinth is slate, but affects none of this.   Hence my confusion.

toocool4

Re: Tonearm height confusion
« Reply #4 on: 11 Nov 2018, 10:37 pm »
Some measure stylus angle with microscopes...  but the quick and dirty is simple.  Put the stylus on a record and put a notecard behind the tonearm.  Look at the lines on the notecard and compare to the tonearm.  If they are parallel, you're all set.  If not, adjust accordingly, raising or lowering the tonearm or shimming the cartridge.

This is not true, parallel tonearm is a good starting point and what you say is only true if the tip / cantilever has been mounted correctly in the cartridge body.
You can start with a parallel arm or scope or what ever, then you need to finish off by ear. The SRA should be around 92 degrees, give or take hence finishing off by ear is needed.

Delacroix

Re: Tonearm height confusion
« Reply #5 on: 11 Nov 2018, 10:38 pm »
I think a picture would be worth a few thousand words here, but if I am understanding you right, the question is not how to set tracking angle of arm (yet)  as much as how to get the arm sitting on the same plane as the plinth?  If so (and ignore if not), one usually can adjust arm pillar height through a mechanism in the arm base but it's been too long since I owned a Rega for me to remember that specific arm structure. If you cannot do that here, if the base is fixed and pillar non-adjustable, then rather than shimming the arm base too much, why not just try to raise the tonearm support base you have by using cards or some other slim, flat material under it so it lifts the whole thing up to the height you want without messing with the arm/armboard interface. Once the base of the arm is at least on the same plane as the plinth, then you can follow Stew's suggestion on minor adjustments. Hope that makes sense....as I say, a pic would help.

bacobits1

Re: Tonearm height confusion
« Reply #6 on: 11 Nov 2018, 10:41 pm »
I would presume the armboard is not the exact problem. The Rega may not work with a thick platter table because you may not be able to even get close to the right height to even clear the platter height. Or have  new armboard ( thicker?) made to work with the Rega.  But, the Rega 300 is a single post/nut model as opposed to the 3 screw mounting. So it has one big nut on the bottom just enough thread for certain thickness plinths.
Gots picts? That would help to see what you are up against.

JoshK

Re: Tonearm height confusion
« Reply #7 on: 11 Nov 2018, 10:42 pm »
I think a picture would be worth a few thousand words here, but if I am understanding you right, the question is not how to set tracking angle of arm (yet)  as much as how to get the arm sitting on the same plane as the plinth?  ...

I'll got take one.  But yeah, the later is my question.  I wonder if it is just a Rega arm thing because Rega platters are so thin.

toocool4

Re: Tonearm height confusion
« Reply #8 on: 11 Nov 2018, 10:43 pm »
Thanks, but neither of you unfortunately gave me any new info.   What I really want to know is what is the standard differential between armboard height and platter height.  I can't imagine there is a lot of variation in this, but the question seems to be answered no-where that I can find.   If there were a lot of variation then most arms wouldn't work on most different tables.  However, I had to shim my Rega over 1" and I still won't clear.  This isn't simple VTA adjustment or minor adjustment, this is big adjustment.

My arm, bearing and platter were all factory from a 260 Table, but my plinth is slate, but affects none of this.   Hence my confusion.

So basically your platter is taller than standard for that turntable, find out from who made the platter the difference and i guess your armboard need to be that much higher than standard for that turntable.

bacobits1

Re: Tonearm height confusion
« Reply #9 on: 11 Nov 2018, 10:53 pm »


Similar to this? The question is, will the Rega arm post threaded is long enough to shim and still attach the bottom nut?

JoshK

Re: Tonearm height confusion
« Reply #10 on: 11 Nov 2018, 10:56 pm »
The arm isn't permanently mounted.  So I perched it in such a way to hopefully get the full picture, but if it doesn't look quite right from the arm's length it is due to where it is seated horizontally, but this doesn't affect the vertical in question here. 

I have another arm (same height) with part of my broken Moerch on it in another photo for more reference. 






JoshK

Re: Tonearm height confusion
« Reply #11 on: 11 Nov 2018, 10:58 pm »
bacobits...yeah similar to that, with different platter material and armboard material though, but otherwise geometrically identical.

As far as nuts to both shim and bolt, got that covered.  I 'countersunk' one armboard for the rega arm on the underside to cover that.  Think like as in countersinking a screw head sort of but in this case I have a larger hole from the bottom so you can fasten the bolt on.

JoshK

Re: Tonearm height confusion
« Reply #12 on: 11 Nov 2018, 11:03 pm »
I appreciate all the quick help I've got, sorry if my first response sounded snipping, wasn't meant.

JoshK

Re: Tonearm height confusion
« Reply #13 on: 11 Nov 2018, 11:06 pm »
So basically your platter is taller than standard for that turntable, find out from who made the platter the difference and i guess your armboard need to be that much higher than standard for that turntable.

In this case the platter and the armboard were standard for the 260, I just changed the plinth out (same dimensions, different material, i.e. slate).

toocool4

Re: Tonearm height confusion
« Reply #14 on: 11 Nov 2018, 11:11 pm »
In this case the platter and the armboard were standard for the 260, I just changed the plinth out (same dimensions, different material, i.e. slate).

Okay either way, you will need a new armboard I think that would be the better solution to fix this issue rather than shimming the arm. Like I said before Rega arms are a pain when it comes to vertical height.

bacobits1

Re: Tonearm height confusion
« Reply #15 on: 11 Nov 2018, 11:12 pm »
Looking at the Rega pict looks correct be it a little high. Can you get the bottom nut on? Opps you did say that.
Yup all of it is a PIA! Sorry..........
Good adjustments would have to be done using threaded after market devices threaded on the top to raise and lower. They are sold for the RB300 still have to have the bottom nut on. Looks like you have shims on there now. At least 2 there.

Michele sells one there are others.

At that point I'd just buy a Jelco arm or something even better. They will have mounting base plates to attach to the armboard with the height adjustments made through that plate and a hex set screws.
 
With that nice quality table that's what I'd do.

JoshK

Re: Tonearm height confusion
« Reply #16 on: 11 Nov 2018, 11:21 pm »
I have had very little experience with arms.  I broke the Moerch (or rather my roommate moved it to where my dog knocked it off of the table) before I even got to mount it.   I plan to have it repaired but Mr. Moerch doesn't do much work anymore these days so there is a  very long wait.  That is why I wanted to get the Rega up and running and I was damned confused.

I plan to buy a Jelco and sell this one, fix the Moerch and ultimately use the Jelco as a second arm with a cart dedicated to unknown quality records.   I have some I am going to use as an armpod with some modifications.   Side question:  would a Denon DL103R work well on the Jelco arm?  I was thinking of grabbing one, don't want to spend a lot of money to get things running.  My Dynavector DH20X is to be found right now and my phono takes one MM/HOMC and one LOMC simultaneously.

sunnydaze

Re: Tonearm height confusion
« Reply #17 on: 12 Nov 2018, 12:07 am »
.....  Side question:  would a Denon DL103R work well on the Jelco arm?  I was thinking of grabbing one, don't want to spend a lot of money to get things running.  My Dynavector DH20X is to be found right now and my phono takes one MM/HOMC and one LOMC simultaneously.

Hi Josh....

Been awhile....how are ya?

The 103R will sound great on the Jelco.   It's a well known synergistic match -- stiff cart + heavy'ish arm = good compliance match = resonant frequency in the right place = good sound.  Google on "103r Jelco" to find all the positive comments.

I use the 103R  (SS level 2 retip) on my Jelco 10 incher, the 750E.  I paid about $600 total used for both.  HUGE buck bang!  Table is Scheu / Eurolab Premier Mk2 (somewhat similar to your Teres) .





I'd say it's worth finding your Dyna 20X.  I have the low output 20X on my Rega 300 arm and it is a great match.  Table is Townshend Rock Mk3.

JoshK

Re: Tonearm height confusion
« Reply #18 on: 12 Nov 2018, 12:41 am »
Thanks, yeah it has been a long time.  I've been spending my spare time with my off-road Jeep mods and deep diving into extreme metal.

I have the high output Dyna 20X somewhere where I put all the rest of my phono stuff but I can't find it at the moment. It'll turn up soonish.  I always wanted to try a loMC but I am not spending a lot more on my LP setup, in fact I am getting rid of all the LPs I wouldn't bother to listen to again and those of poor quality (my Dad's LPs).    The Denon 103 seems like a good inexpensive introduction along with the Dyna 20X when I can find it.  Two arms that I can use simultaneously seems like a cool thing to have.  Arms can be the Moerch when fixed and the Jelco to replace the Rega.


sunnydaze

Re: Tonearm height confusion
« Reply #19 on: 12 Nov 2018, 12:49 am »
I use several arms on my Scheu.     The way I deal with arm height differences is to use different sized spacers under the arm plate (easily obtained at my local ACE hardware store).  I also cut a specific plate for each arm to deal with the different arm mounting schemes and mount distances.  I use 20mm thick bamboo cutting boards -- very cheap at many stores.  The stock acrylic board is 20mm thick, so this works nicely.

Refer to my pic in above post showing the table, and I'm sure this is clear.  Maybe with a machinists help or even some DIY skills you can figure out an easy way to do this?   It looks like your current cantilevered board would need to be lower, then you'd need to build on top of it, possibly with spacers just like the Scheu so you have adjustability?

I always endeavor to get the cue platform level with the platter when the arm pillar is halfway up.  This works well with all the arms I've installed on the Scheu.  But then again, unlike the Rega, all my arms allow for VTA adjustments from that position to fine tune the sound.  Personally, I would not own an arm without VTA adjustment.  For some stylus profiles it is a very important parameter.  You can buy after-market ones for your 300.   Max Townshend modified the Rega arm included on my Rock to include a VTA adjuster.