Stew,
This is interesting, would it be possible to post a diagram or drawing of this?
I'd like to try the "219" on my recently aquired Sota TT and this would probably be a big help as I'm not real swift when it comes to TT geometery.
I'm also concerned that my application to the Nanook 219 group hasn't been accepted.
Best Regards,
TerryO
Terry....all members of the "friends of nanook" group get an automati pass into ...
free pass into the "nanook analog" group. All in the friends group are far more knowledgeable than I in certain aspects. I think I'm a pretty good "all rounder", though.
For any that may wish to get a little more involved in the design aspects (tonearms, turntable designs and imlementations), please look here.
The turntable "transom" was something I designed some time ago. It is dubb-simple (as I like it). However all my drawings disappeared in the recent HD calamity. I have to redraw it...
free pass into the "nanook analog" group. All in the friends group are far more knowledgeable than I in certain aspects. I think I'm a pretty good "all rounder", though.
For any that may wish to get a little more involved in the design aspects (tonearms, turntable designs and imlementations), please look here.
The turntable "transom" was something I designed some time ago. It is dubb-simple (as I like it). However all my drawings disappeared in the recent HD calamity. I have to redraw it...
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moray, of course!
glad you've looked in on this. I value your input.
I've finally got my hands on a suitable motor for Bob's table. Think of this motor as a "super" Merrill motor 🙂
If all works out, I think this could become the standard for motors I use.
glad you've looked in on this. I value your input.
I've finally got my hands on a suitable motor for Bob's table. Think of this motor as a "super" Merrill motor 🙂
If all works out, I think this could become the standard for motors I use.
Am I wrong about this? I designed and built my 'Cedar Arm' as shown. I have been setting its Base so that the Stylus is Dead Center over the Spindle. It's not that hard, and you need no Gauges or Tools to do it...A Circle is a Circle, and no matter where you place a point of Rotation around it, if an Arc crosses the Center Point of a Target Circle you will get what I've shown...
Not quite so simple. The stylus will overhang the spindle by a distance depending on the alignment used. In other words the effective length (pivot to stylus tip) will be greater than the pivot to spindle distance. The difference between them is the overhang.
Go to vinylengine dot com and set up an account. That site is an invaluable tool to help understand this. It has a web calculator to allow you to cad up a protractor for your arm.
You can set up your protractor depending on what type of alignment you want.
Go to vinylengine dot com and set up an account. That site is an invaluable tool to help understand this. It has a web calculator to allow you to cad up a protractor for your arm.
You can set up your protractor depending on what type of alignment you want.
Where are your null points? The least overall distortion is not at the spindle and outer edge of the record, but somewhere in between.
For an effective length of 259mm the pivot to spindle distance would be 243.11 and 242.67 for a Baerwald and LofgrenB alignment repsectively. The stylus would overhang the spindle by 15.9 and 16.3mm respectvely as well.
The inner null points 66.0 and 70.3 and outer null points would be 120.9 and 116.6.
There is a good diagram with the calculator which shows the tracking distortion profile across the album as well as a plot like yours which incorporates the overhang, linear offset and other dimensions. I have not yet sat down to master the math behind it to be able to describe the reasons mathmatically, however I used the site to learn how the different aligments work and what the impacts are.
For an effective length of 259mm the pivot to spindle distance would be 243.11 and 242.67 for a Baerwald and LofgrenB alignment repsectively. The stylus would overhang the spindle by 15.9 and 16.3mm respectvely as well.
The inner null points 66.0 and 70.3 and outer null points would be 120.9 and 116.6.
There is a good diagram with the calculator which shows the tracking distortion profile across the album as well as a plot like yours which incorporates the overhang, linear offset and other dimensions. I have not yet sat down to master the math behind it to be able to describe the reasons mathmatically, however I used the site to learn how the different aligments work and what the impacts are.
All I did was make it track at 90 Deg. at the middle of the Grooves, where it shows 90 Deg...Got a better Idea?
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Yep. Read up on Vinylengine. You are close in your thinking, but in reality, by shifting the arc swung by the stylus away from the spindle, you can have two null points instead of one during playback. Null points being when the stylus is perfectly parallel to the grooves. By doing that, you then reduce the peak and rms distortion when the stylus is not on the null point.
I think you will see what these alignments mean and why they produce the lowest distortion. Each one has its merits depending on RMS or peak value. You certainly can get significantly lower distortion and better tracking than what you have drawn.
I think you will see what these alignments mean and why they produce the lowest distortion. Each one has its merits depending on RMS or peak value. You certainly can get significantly lower distortion and better tracking than what you have drawn.
Well, what Null points would you like Greg, 1/3 and 2/3 in? I can swing this to Spot it anywhere you think will be the best point for anyone using this Arm to Set it up Nice and Easy...
Ah...Fuggetabout it...It's Sat Nite and I'm back at work? I'm going to spin some Vinyl now... Anyone want 2 Null Points? Well that will be all of .04" on your Setup....Go for It..
Your choice. Happy listening. Remember you where the one asking if "Is this Wrong". Technically you could rotate it 180 degrees and it would still play.
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arm "kits" and stuff...
-The arm kits were made so that the resulting arm has an effective length of 12" (or 304.8mm).
to check the actual arm length of the kit you received, measure the length from the pivot to the end of the arm shaft (the "long" end, that is). Add 39mm to the previous measurement. This will give you the effective length. Some of the arms may be a few mm short, or a few long, compared to the typical 304.8mm effective length. Decide on the amount of overhang desired. I used 10mm.
consider this:
Opera ST600:
(from the vinylengine database)
I just looked for an arm with similar dimensions to what I ended up with (330mm effective length, mine is the longest... but not intentionally) and mimicked the measurements. In my case I used the Ortofon 309 as the basis for my arm on my table. Effective length= 326mm, O/S=19°, O/H=15mm. I then used an alignment protractor to set it firmly (using only one point).
YMMV, but be as simple as possible. Some offset is required. Just search out an arm with similar (final) dimensions as you end up with. I used the length from the back edge of the headshell moving in a forward direction 39mm as to where my stylus would end up. It is pretty close.
-The arm kits were made so that the resulting arm has an effective length of 12" (or 304.8mm).
to check the actual arm length of the kit you received, measure the length from the pivot to the end of the arm shaft (the "long" end, that is). Add 39mm to the previous measurement. This will give you the effective length. Some of the arms may be a few mm short, or a few long, compared to the typical 304.8mm effective length. Decide on the amount of overhang desired. I used 10mm.
consider this:
Opera ST600:
- effective length:=300mm
- Offset:=16°
- Overhang:=20mm
(from the vinylengine database)
I just looked for an arm with similar dimensions to what I ended up with (330mm effective length, mine is the longest... but not intentionally) and mimicked the measurements. In my case I used the Ortofon 309 as the basis for my arm on my table. Effective length= 326mm, O/S=19°, O/H=15mm. I then used an alignment protractor to set it firmly (using only one point).
YMMV, but be as simple as possible. Some offset is required. Just search out an arm with similar (final) dimensions as you end up with. I used the length from the back edge of the headshell moving in a forward direction 39mm as to where my stylus would end up. It is pretty close.
I just measured the O/S...
on my long arm. It appears to be 20°, measured with a machinists protractor (another great measuring device).
The total effective length is 332mm, the pivot to spindle is 311mm , measured with my best "eyeballing" technique. Using the vinylengine's tonearm geometry comparator, the best numbers I end up with are via the Baerwald alignment.
Effective length= 332mm
pivot to spindle= 319.758mm
O/S=16.347°
O/H= 12.242mm
Linear Offset= 99.345mm
Inner null= 65.998
Outer null= 120.891
Max distortion= 0.426
Avg distortion RMS= .279
This seems pretty reasonable to me. I'll move the pivot to this location and listen some tonight.
wjlamp, where are you? have you listened at all?
arms are cut. I'll try to get the bearings installed tonight.
Beta testers: do you want to figure out your own pivot mount? Let me know. Can be as simple as the ones Bernie made...
on my long arm. It appears to be 20°, measured with a machinists protractor (another great measuring device).
The total effective length is 332mm, the pivot to spindle is 311mm , measured with my best "eyeballing" technique. Using the vinylengine's tonearm geometry comparator, the best numbers I end up with are via the Baerwald alignment.
Effective length= 332mm
pivot to spindle= 319.758mm
O/S=16.347°
O/H= 12.242mm
Linear Offset= 99.345mm
Inner null= 65.998
Outer null= 120.891
Max distortion= 0.426
Avg distortion RMS= .279
This seems pretty reasonable to me. I'll move the pivot to this location and listen some tonight.
wjlamp, where are you? have you listened at all?
arms are cut. I'll try to get the bearings installed tonight.
Beta testers: do you want to figure out your own pivot mount? Let me know. Can be as simple as the ones Bernie made...
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I have thought of making an "offset" mount ala yours, Nanook. I will mount the arm on my diy table with space for two arms, and compare it with a SME 3009 S2 impr. I have the possibility to use the same stylus in both arms, it should give it a fair comparision, I believe. I have a couple of test records, and can check results on a scope in addition to listening tests, of course.
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Nope.
Took me a longer time than expected, to drill the hole for the wires exit.
I am still in the wide open. After all,I hold my reputation for being tortoise fast while doing things. I am kind of perfectionist,and thus slower than slow motion.
But it goes fine,so far ..,😀
B.L.
moved pivot point...
wife was off work last night (she's a RN), due to illness. So no music 🙁
I'm convinced that the alignment I posted is pretty good, perhaps as good as it gets and is the best possible based on playing around with the overhang comparator, and alignment calculators, elsewhere.
wjlamp: drilling even a small hole can be difficult.
All tonearm kits will use black tubing as per the arrow shafts I could get without spending $100 for 5...
I think I may have the headshells figured out...
Will post stuff tonight.
nicoch46: the pivots are the same, perhaps the holders will be different. If the base is too light, it does not offer much in terms of stability. That's why I like the collars that have set screws to allow holding the pivot "tubes" firmly.
.
wife was off work last night (she's a RN), due to illness. So no music 🙁
I'm convinced that the alignment I posted is pretty good, perhaps as good as it gets and is the best possible based on playing around with the overhang comparator, and alignment calculators, elsewhere.
wjlamp: drilling even a small hole can be difficult.
All tonearm kits will use black tubing as per the arrow shafts I could get without spending $100 for 5...
I think I may have the headshells figured out...
Will post stuff tonight.
nicoch46: the pivots are the same, perhaps the holders will be different. If the base is too light, it does not offer much in terms of stability. That's why I like the collars that have set screws to allow holding the pivot "tubes" firmly.
.
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listened tonight...
to the "new alignment". Fresh Aire , Toccata en Fugue was most excellent.
Paul Simon's Graceland was about as good as I've ever heard it (even on more expensive systems). Some Carlos Santana and Sting, maybe a little bit of Supertramp tonight. I'm really likin' it on my Oracle. (its no slouch on the Sugden either 🙂 ).
If this thing makes me want to listen to all the music I have on LP (and it does), it must be doing something right.
to the "new alignment". Fresh Aire , Toccata en Fugue was most excellent.
Paul Simon's Graceland was about as good as I've ever heard it (even on more expensive systems). Some Carlos Santana and Sting, maybe a little bit of Supertramp tonight. I'm really likin' it on my Oracle. (its no slouch on the Sugden either 🙂 ).
If this thing makes me want to listen to all the music I have on LP (and it does), it must be doing something right.
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