Re: Cracks in the bobbins?
While someone like Frank has been 'behind the velvet rope' and can say for certain...my guess would be in part to do with the current material being a little more cost effective than the butyrate that was used a while back.
Sometimes cost is a factor, sometimes resistance to warping in the heat from wax potting, or choosing a material that is the "shiniest" or whatever. Different materials look more or less shiny, or they come off the mold with a texture. As for the sound, and using butyrate on vintage style pickups,
I will start by saying this: It's an extremely small difference, so small that I completely understand if someone says "it makes no difference." But the fact that it does make a difference means it's on my radar. I am the one who personally conducted the tests while behind the velvet rope as you say.
Ok, then..the next question is what kind of effect does the material have on the sound? Is it something that can be compensated for changing the wind or other materials? Is the current material used 'because it has always been that way' or is there a sonic reason?
I can't (and wouldn't) reveal trade secrets. Every company has the right to privacy. I can say things that are already public knowledge, like "Vintage PAF's used butyrate" and of course I can
repeat things that I already said in print or video while working for SD, because by that nature they have become public knowledge. So while at SD I shared some bobbin material information on a pickup makers forum, along with sound clips. But I withheld the data about some of the actual materials used, with a couple of exceptions. Basically I said I didn't like ABS. It was twangy and ringy, kind of harsh. I also talked about how I/we felt glass filled nylon sounded the "best" knowing full well that best is subjective, but it's what led to the GFN being used on the Zephyrs. It was balanced, clean, added nothing that you didn't want. In between those, there were several materials I did not disclose, other than to point out that they were "in between", and that liking GFN didn't necessarily mean that we also liked straight nylon without the glass fill. It wasn't about the nylon, it was about the stiffening and dampening factors of the glass fill.
The thing about the bobbin material is that if you do agree there is a difference, no matter how small, then no, you can not change a wind or shift tension or any of those things to compensate. If a Seth Lover has a butyrate bobbin, you can't (in my opinion) change something to make it sound the same on GFN. But I concede that to most people a Seth Lover on GFN maybe
would sound exactly the same to them.
All of this to say that if you're ordering a pickup from MJ in the Custom Shop for example, its not just the decision to get butyrate, or the "normal" Duncan bobbin. You can ask for the glass filled nylon bobbins from Zephyrs to be used, and find out for yourself. (Same is true for the bimetallic pole pieces. Those things are great)
