Here are null points (last 2 lines) for 12" record DIN radiuses (first 2 lines). You can check my prior posts on this thread for JIS.Since we’re talking IEC null points here, would any of you happen to know what the DIN null points are for Lofgren A & B? I’ve looked on line and haven’t come up with anything - I would think there’d be a chart somewhere listing all the null points for all the different geometries for every standard, e.g., IEC, DIN, JIS, etc. Please let me know if you have a source -thanks
Good luck on explaining that.@miglto Yes, thanks - those are IEC, I’m specifically looking for the DIN version of those null points.
@mtemur Thank you!Here are null points (last 2 lines) for 12" record DIN radiuses (first 2 lines). You can check my prior posts on this thread for JIS.
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Really not sure where all the attitude is coming from, but it has been quite unpleasant throughout this thread.Good luck on explaining that.
Sorry to hear that sensibly warning a member is unpleasant to you.Really not sure where all the attitude is coming from, but it has been quite unpleasant throughout this thread.
Treating a different member with such animosity as you continually display to miglto is unpleasant and unnecessary.Sorry to hear that sensibly warning a member is unpleasant to you.
Please add IMHO to your post cause it only reflects your opinion.Treating a different member with such animosity as you continually display to miglto is unpleasant and unnecessary.
IMO this isn’t about style, and IMO you are completely aware of that.Please add IMHO to your post cause it only reflects your opinion.
IMHO your jumping in with a judging style is unnecessary and unpleasant.
Really interesting. Anyone has a link to the full pdf of the book (it is at this point public domain).Please excuse me if this has already been posted:
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rca :: Radiotron Designers Handbook 1954 : Free Download, Borrow, and Streaming : Internet Archive
From the bitsavers.org collection, a scanned-in computer-related document.rca :: Radiotron Designers Handbook 1954archive.org
The entire book is available in that link I posted. Otherwise there were lots of PDF versions on the net.Really interesting. Anyone has a link to the full pdf of the book (it is at this point public domain).
Thx. Did not realize there was a download option. I downloaded from this link, this book is amazing. Thank you!The entire book is available in that link I posted. Otherwise there were lots of PDF versions on the net.
Almost all pivoted arms have overhang and offset at the headshell. This design choice reduces tracking error by enabling two tangential radiuses over the record surface. Those are called null points. Each geometry whether Lofgren A, B or Stevenson has a different approach at handling distortion. Depending on your choice of geometry distortion level is going to change which will inevitably effect the sound.I have looked at these on my protractor never knew how they differed. I understood they meant the 2 null points were different. But, is there any reason any, either, or would sonically sound different.
No. Sonics are impacted by both geometry of the stylus relative to groove (zenith, azimuth, SRA) and geometry of the arm relative to grooves (overhang, offset)Or are the sonics only impacted by the geometry of the diamond tip to vinyl surface contact.
Yes, if you set zenith correctly. Zenith is more related to cartridge alignment than geometry.The null points only being where rhe diamond at 2 points has its Zenith correct to the groove.
Cutting engineers don’t always conform to the standards and cut longer even in the country that set the standard. This makes it even more complicated.An anecdote (I may have posted it before, and if in this thread way before the off topic discussions):
I measured the innermost modulated groove radius of the by now well documented side three of the DG TOS release of the Brahms piano concertos with Gilels and Jochum to 52 mm. Putting that into a Löchern A/Baerwald calculator I got 57.5 mm as the inner null, the same as Stevenson DIN.
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