So, was doing some reading online and discovered an ironic twist of fate, after coming to the 2-2.5" long arm sounding/working best I have discovered that the front to back length of the most commonly used Neumann sx74 cutterhead is 2.5" or 6.4cm deep. Kind of makes some sense, since on a lathe the horizontal movement is a feed screw on a track and the cutterhead is pivoted to set it into the lacquer which would place the vertical pivot at just over 2.5".
Colin
Colin
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I believe there are a few things which suggest the longer the arm, the better.
for tracking a warped record, the VTA will change more with a shorter arm, increasing distortion
increased moment when trying to move the carriage, needing less effort from the stylus/cnatilever
general convenience (not having to move a short arm out of the way each time a record is changed)
there are disadvantages, which I am sure you will point out.
for tracking a warped record, the VTA will change more with a shorter arm, increasing distortion
increased moment when trying to move the carriage, needing less effort from the stylus/cnatilever
general convenience (not having to move a short arm out of the way each time a record is changed)
there are disadvantages, which I am sure you will point out.
I believe there are a few things which suggest the longer the arm, the better.
for tracking a warped record, the VTA will change more with a shorter arm, increasing distortion
increased moment when trying to move the carriage, needing less effort from the stylus/cnatilever
general convenience (not having to move a short arm out of the way each time a record is changed)
there are disadvantages, which I am sure you will point out.
the only problem i see with short arm is the vta differences between say 120gr and 180/200gr vinyl. For wraped records at least i do use a ring clamp - even a perfecly flat record sounds better with one, so its a given Accessory if you ask me.
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That's it, we should stop this nonsense and solely rely on the convenient CD! . Just in my opinion, but to be honest I don't find it any more difficult to change records with a short arm, though ymmv. On the Vta aspect, yes a shorter arm cannot defy the basic rules of physics, but for as many cons pointed out it has benefits that a longer arm often lacks. It is however easier on the stylus to move a shorter arm, especially with a mechanical bearing and is best to have a shorter tip to pivot length for the horizontal movement. I've tried both, a longer arm increases friction and puts more stress on the stylus. This however does not include air bearings, but that's a whole different realm.
Colin
. Just in my opinion, but to be honest I don't find it any more difficult to change records with a short arm, though ymmv. On the Vta aspect, yes a shorter arm cannot defy the basic rules of physics, but for as many cons pointed out it has benefits that a longer arm often lacks. It is however easier on the stylus to move a shorter arm, especially with a mechanical bearing and is best to have a shorter tip to pivot length for the horizontal movement. I've tried both, a longer arm increases friction and puts more stress on the stylus. This however does not include air bearings, but that's a whole different realm. Colin
RollE2k, I use my ring-clamp on every record for 100% of the time.
Just to be sure the record is tight with the platter.
p.s. I d`nt buy warped records.
Hans.
Catssquirrel,
A longer arm will exhibit more torque side to side at the bearings, since a longer arm provides a better lever for this torque. The closer the stylus is to the bearings the less this applied pressure is translated into any significant side torque at the bearings. This torque essentially makes the bearings want to run up the tube but gravity and mass doesn't permit it, so friction will increase. The first benefit of the shorter arm is an utter absense of arm induced coloration of the sound, probably why short linear arms have been called dry sounding, it's closer to good digital, but better.
Colin
A longer arm will exhibit more torque side to side at the bearings, since a longer arm provides a better lever for this torque. The closer the stylus is to the bearings the less this applied pressure is translated into any significant side torque at the bearings. This torque essentially makes the bearings want to run up the tube but gravity and mass doesn't permit it, so friction will increase. The first benefit of the shorter arm is an utter absense of arm induced coloration of the sound, probably why short linear arms have been called dry sounding, it's closer to good digital, but better.
Colin
Not digital in the extreme sense, just a lot cleaner than an average pivoted arm, more resolved but I've found pivoted arms can have overhang or a tendency to smear the sound making notes seem longer even if its minor. The speed of the short arm carriage is fast in resolving nuances, sometimes the longer pivoted arms will also create body that is not there on the recording. On vinyl it's between the sound and extended resolution, I do use a cd for comparison to keep things on track on how he general presentation should be.
Colin
Colin
That is most likely the case. It really bothers my ears, haha, the pace of the music is important to me and energy storage disrupts this enjoyment. Was noticing last night throwing some warps at the arm, it still tracks them like.a champ and notice no stand out speed wows, this tells me I have achieved an ideal compromise of dimensioning.
Colin
Colin
I made a great score today in my quest to build one of these arms. I went to a sporting goods chain where they sell archery supplies. I asked the guy if they had carbon arrows and described what I wanted to do with them. He told me to follow him and gave me a box of end pieces for arrows. These are between 3.5" and 6" long, mixed lot, and about 50 of them. 7.5mm OD, with a 1mm wall thickness. I think it will probably work pretty well.
If you need to find a cheap place to get your arm rod stuff, try an archery shop where they customize arrows for hunters. They apparently throw this stuff away.
If you need to find a cheap place to get your arm rod stuff, try an archery shop where they customize arrows for hunters. They apparently throw this stuff away.
Excellent find, a couple mm larger than I used but will work just fine, especially for free!. If you build this within proximity close to the way it was originally designedI can guarantee sonics that will impress!. I'm thinking up next possibly a phono stage?, I have one to offer based loosely on the original vendetta ala John Curl, but single ended with opamps that will astound, passive 2.122khz pole with active 500hz zero and 50hz pole. Controversally I have included the 50 kHz Neumann zero in the design.
Colin
Colin
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Question for you guys.....
I have a thorens td150 turn table. The platter and arm board are on a suspension system and move together. Think linn sondek.
Would this be appropriate for this arm build or would I want to use a deck where the platter isn't suspended in any way, like say a rek-o-kut?
I have a thorens td150 turn table. The platter and arm board are on a suspension system and move together. Think linn sondek.
Would this be appropriate for this arm build or would I want to use a deck where the platter isn't suspended in any way, like say a rek-o-kut?