Baerwald, the Conrad Hoffman Arc Template Generator, Wine, WineBottler, and Perfect Alignment
Recorded on March 24th, 2016
Things have reached a new level of crazy in this house.
I had been using 1/4” of underhang on the DIY tonearm, with the AT120Eb mounted parallel to the arm, but with yesterday’s listening tests, I could hear that the cart was way out of alignment on the first couple of tracks on most albums. I could see it, too, but initially chose to ignore it, thinking that the trade-off in reduced side-force on the stylus would be worth it. It wasn’t.
Thus began what we call “hotbrain”, where I would do rapid-fire research on the iPhone and append every promising page URL to one entry in Drafts. That draft got quite long by the end of the hotbrain.
First was research into whether a 12” tonearm really needed an offset cartridge, or if straight would be good enough. I found a very religious, heated thread about “Tonearm without off-set” on Audiogon, where I learned that:
The sonic benefits of highly accurate alignment are huge. Search this forum for “Mint” or “MintLP” protractor for a wealth of information and testimonials across a wide range of tonearms and cartridges. You’d be shortchanging yourself not to have the best possible alignment, which won’t be feasible without a properly angled headshell.
This led to a hunt for the Mint LP protractor, a rather expensive custom-generator protractor they mail you after getting your turntable and tonearm model numbers.
Ah, but then this post about the Mint on the Steve Hoffman boards:
I own a Mint but prefer to use an arc protractor generated by Conrad Hoffman’s software, which is what I was using before I purchased the Mint.
Now I was fully converted to abandoning underhang in favor of using overhang + Baerwald alignment. The only problem was the highly-regarded – and free – Conrad Hoffman custom arc generator only ran on Windows. All I have are Macs.
This is where the crazy starts. I didn’t want to deal with downloading a copy of Windows and then a trial of VMWare to install the Conrad Hoffman software, so I was actually this close to signing up for a free trial of a Microsoft Azure hosted virtual machine. But then I read about the hurdles you have to go through to install third-party apps on such a service, and kept looking.
I thought later, “What’s the simplest thing that could work?”, and re-discovered Wine/WineBottler, a way to run some Windows programs on a Mac without installing Windows. I tried it, ran the Conrad Hoffman generator, and was surprised when it ran!
Only thing to figure out was what I wanted my spindle-to-pivot distance to be, since that’s the only parameter you enter about your own system. If I wasn’t doing underhang anymore, I had to come up with a suitable overhang for a roughly 12” straight arm. I found a post mentioning one of the Nanook 219 iterations, and someone said they designed theirs to have 14mm of overhang, and their arm was a similar length to mine. That seemed good enough, so I moved the arm pivot, measured the spindle-to-pivot distance as 308mm, and plugged it into the generator. Conrad’s readme file said that if you didn’t want to make a research project out of it, to just go with the DIN setting and Löfgren A (Baerwald). Those inner- and outer-groove measurements looked close enough when I measured a real LP.
I held my breath and clicked “Print Arc Template” and was relieved to see our wireless printer listed in the Windows print dialog. I clicked “Print” and heard printing noises starting up in the next room. I had to print one more copy after correcting for the Y-axis scale. I put it on the turntable, temporarily taped down the platter (per the instructions), lined everything up, and pretty easily got the cart aligned with the arc and the guides. I moved the stylus over a real LP and could see that the stylus was actually very closely aligned with the grooves all way way through the arc. Never got that close before.
I tightened it back in the headshell, put on Minute By Minute by the Doobie Brothers, and was carried away by the sound of perfect alignment all the way through the album side. It was involving and suspenseful, like a live performance that I didn’t know the outcome of. Every voice and instrument perfectly defined and weightless. I heard ambience cues that I never noticed before, and at the end of each song, lots of details that were masked previously. I’m a believer.
If you suspect you need alignment help, go for the Conrad Hoffman custom arc generator. And don’t be scared off if you have a Mac!