An experiment I cannot do... gooseneck tonearms
Posted: Wed Apr 10, 2019 9:49 am
An experiment I cannot do...
While observing in this forum and elsewhere the old style HMV/Victor machines that have the gooseneck tonearm, a wicked idea has arised on my mind. This I cannot put into effect, for I don't own one of these machines, nor I have access to any.
It seems there were several versions of this tonearm:
1) the first one with thin tonearm and gooseneck, the soundbox placed in the tonearm axis, so when the gooseneck is flipped over to the rest position, it falls on the tonearm.
2) a second version, equal to the first one in the essential, but using a fat tonearm.
3) a later version with a long gooseneck, so when the gooseneck is filpped over to the rest position, the soundbox falls at the inner side of the tonearm, between the tonearm and the TT spindle.
These three versions, and especially the (3) have a common fatal design error: the tracking is horrible, especially at the outer edge of records. The system seems to be designed so that the needle point falls on the TT spindle. Horror...! And the 'improvement' (3) is stioll worse, for it impairs the offset —the theoretical distance between the diaphragm plane and the tonearm base joint axis—. Still worse horror... Panic...!
I cannot attest this 100%, for I have no gooseneck machines to test. I'm only speaking based on the photos and videos I've seen.
There was years ago a thread (maybe at 78-L) about an improved gooseneck, which used a slightly different design; the U-tube (I'm tired of writing goosenecks,
) was not a 180 degrees turn, but a more open angle (160 degrees, f.i.) so the offset was far better, and so the tracking error was reduced. EMG gooseneck tonearms have, of course, taken this into account in the design, and tracking is near perfect.
You can see why version (3) of the arrangement, for this very reason, was worse than (1) and (2). They moved the soundnbox in the opposite direction to what is needed.
I'm always thinking that if I ever had one of those machines, the first thing I would try is to reverse the gooseneck position: instead of being installed to the outside (with respect to the TT spindle), closing screw on the outside, I would invert this arrangement, reinstalling the U-tube it at the outside, leaving the closing screw at the inside. This looks as it can improve tracking somehow. At least, the offset, especially in model (3), would be improved. Of course, the soundbox would have to be installed a-la-Panatrope, with the backplate at the outside. The only inconvenient I see is that the pin for the soundbox zenith angle would have to be removed, so the soundbox can be mounted on the gooseneck in reverse.
Would any kind and daring soul in this forum make the experiment for me, and send before-and-after photos, so we can see the tracking results...?
If there's someone, many thanks. You've helped me to pay off about this matter...
If not, I would have to look for a gooseneck machine at a museum or somewhere, near the closing time, and try myself very fast, when nobody's looking...!!!
While observing in this forum and elsewhere the old style HMV/Victor machines that have the gooseneck tonearm, a wicked idea has arised on my mind. This I cannot put into effect, for I don't own one of these machines, nor I have access to any.
It seems there were several versions of this tonearm:
1) the first one with thin tonearm and gooseneck, the soundbox placed in the tonearm axis, so when the gooseneck is flipped over to the rest position, it falls on the tonearm.
2) a second version, equal to the first one in the essential, but using a fat tonearm.
3) a later version with a long gooseneck, so when the gooseneck is filpped over to the rest position, the soundbox falls at the inner side of the tonearm, between the tonearm and the TT spindle.
These three versions, and especially the (3) have a common fatal design error: the tracking is horrible, especially at the outer edge of records. The system seems to be designed so that the needle point falls on the TT spindle. Horror...! And the 'improvement' (3) is stioll worse, for it impairs the offset —the theoretical distance between the diaphragm plane and the tonearm base joint axis—. Still worse horror... Panic...!
I cannot attest this 100%, for I have no gooseneck machines to test. I'm only speaking based on the photos and videos I've seen.
There was years ago a thread (maybe at 78-L) about an improved gooseneck, which used a slightly different design; the U-tube (I'm tired of writing goosenecks,
) was not a 180 degrees turn, but a more open angle (160 degrees, f.i.) so the offset was far better, and so the tracking error was reduced. EMG gooseneck tonearms have, of course, taken this into account in the design, and tracking is near perfect.You can see why version (3) of the arrangement, for this very reason, was worse than (1) and (2). They moved the soundnbox in the opposite direction to what is needed.
I'm always thinking that if I ever had one of those machines, the first thing I would try is to reverse the gooseneck position: instead of being installed to the outside (with respect to the TT spindle), closing screw on the outside, I would invert this arrangement, reinstalling the U-tube it at the outside, leaving the closing screw at the inside. This looks as it can improve tracking somehow. At least, the offset, especially in model (3), would be improved. Of course, the soundbox would have to be installed a-la-Panatrope, with the backplate at the outside. The only inconvenient I see is that the pin for the soundbox zenith angle would have to be removed, so the soundbox can be mounted on the gooseneck in reverse.
Would any kind and daring soul in this forum make the experiment for me, and send before-and-after photos, so we can see the tracking results...?
If there's someone, many thanks. You've helped me to pay off about this matter...
If not, I would have to look for a gooseneck machine at a museum or somewhere, near the closing time, and try myself very fast, when nobody's looking...!!!
