Official AR Turntable Owners Thread

Marc/anyone, probably a stupid question, but how do you measure the frequency when adjusting the springs?
 
Marc/anyone, probably a stupid question, but how do you measure the frequency when adjusting the springs?
You measure the compressed height of the spring with it loaded . measurements about in marcs post. So the height of the spring should be no less than 30mm with everything in place .
 
You measure the compressed height of the spring with it loaded . measurements about in marcs post. So the height of the spring should be no less than 30mm with everything in place .

No he wants to measure the frequency of the springs once loaded.

Not 100% sure but it might be the number of bounces after the spring has been excited . So for us it be 3.5 bounces before it settles? Once again not quite sure on this.
 
No he wants to measure the frequency of the springs once loaded.

Not 100% sure but it might be the number of bounces after the spring has been excited . So for us it be 3.5 bounces before it settles? Once again not quite sure on this.
no, the number of jounces per second. On my set up jig before any damping is applied, It will jounce for several minutes. the frequency in a spring is determined by the amount of its deflection from static height due to load. A compression coil spring will not have a controlled resonate frequency until its deflection from static (loaded length) is 80% of static. it will have a frequency above that, but it is not controlled. It is more like a truncated sawtooth wave at top and bottom. The jounce should resemble a sine wave. in a controlled sine wave , it is burning off 18db per octave. in an uncontrolled sine, it is transferring un damped energy into the subchassis at that frequency. Lets try this as a "visual" undamped car springs (bad shocks) it will have approx 1.5-1.7 hz. it may make you car sick to ride in it. put on truck springs, the frequency will be higher, and over those same bumps not only are you getting car sick, but you're getting a good jolt at top and bottom of spring travel.
 
Marc/anyone, probably a stupid question, but how do you measure the frequency when adjusting the springs?
one can't change the frequency when adjusting the springs, one can only adjust the ride height relative to the top plate. the frequency is determined by the mass of the suspended pieces.
 
i got curious recently and does anyone know of a cartridge overhang / alignment gauge for the AR's that have the S wand mod?
i know its reccomended to be in the 226-228mm ballbark but dang if its hard for my eyes to read a ruler that small. i think im at like 222 but not much room to move the cart out further.
 
i got curious recently and does anyone know of a cartridge overhang / alignment gauge for the AR's that have the S wand mod?
i know its reccomended to be in the 226-228mm ballbark but dang if its hard for my eyes to read a ruler that small. i think im at like 222 but not much room to move the cart out further.
I would suggest using Conrad Hauffmans protractor printer, if you havent it is an amazing thing.
http://conradhoffman.com/TemplateGen.zip

How far into the tonearm block is the wand? Can you slide it out some?
 
I would suggest using Conrad Hauffmans protractor printer, if you havent it is an amazing thing.
http://conradhoffman.com/TemplateGen.zip

How far into the tonearm block is the wand? Can you slide it out some?

hmm thats a windows file i'll have to borrow the wifes computer.

i did actually re-measure but in chunks this time, pivot to front of block, front of block to base of headshell and then base of headshell to stylus tip.
that all comes out to right at 228.

no idea how that was easier than straight measure pivot to tip but it was easier to read. Wish there was an easy overhang gauge like technics has.
 
i got curious recently and does anyone know of a cartridge overhang / alignment gauge for the AR's that have the S wand mod?
i know its reccomended to be in the 226-228mm ballbark but dang if its hard for my eyes to read a ruler that small. i think im at like 222 but not much room to move the cart out further.
if the arm has the SME type mount tube, and it a technics type tube, overhang to get close to baerwald will be 18-19mm (228-229 total length from pivot center to sylus tip) and maybe a deg or 2 of toe in.
 
Are you using Linux?
If so the file will run using WINE,
mac i can set up emulation, just havent yet easier to borrow her laptop :)


if the arm has the SME type mount tube, and it a technics type tube, overhang to get close to baerwald will be 18-19mm (228-229 total length from pivot center to sylus tip) and maybe a deg or 2 of toe in.

i seem to be setup correct right now, but yes its sme mount and technics type tube. the 18-19mm would be from what point?
 
So I set my XB with 15mm of overhang and aligned it to a Baerwald mirror protractor. No? I recall 16.2mm of overhang and square in the headshell?
 
So I set my XB with 15mm of overhang and aligned it to a Baerwald mirror protractor. No? I recall 16.2mm of overhang and square in the headshell?
your arm tube may not be in as far into the pivot block as i normally set these days. Don't remember. either way is fine. might check overall effetcive length
 
I replaced the vintage belt on an AR XA with a new belt, which reduced the 300 Hz motor noise significantly. But it's still audible, albeit at a much reduced level. Is there anything else that I can do to eliminate the noise?
 
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