#1
Hi

I have just changed string gauge on my Ibanez rg3550mz from 10s to 9s and adjusted the trem accordingly.
After the change the intonation on the D and A strings went way off. The weird thing is; the intonation on the D string went flat and on the A string it went sharp. I was able to compensate on both strings, but almost ran out of adjustment space. So now the A string saddle is almost as far back as it'll go and the D string saddle is almost as far forward as it'll go.

So, I did some research and discovered that sometimes there may be a bad string. I changed to a new set (the strings are DR tite fits 9-42) which I bought at the same time as the one I had problems with. However, I still have the exact same problem.

I have done some more research and it seems that neck relief can affect intonation aswell. When measuring by the method of fretting 1st fret and the place where the neck meets the body, the neck relief is about 0,25 mm which is lower than what is recommended by Ibanez (0,3-0,5 mm). I am going to give it a shot tomorrow but my research led me to believe that only too much relief will cause intonation problems.

So what I am asking is this:

1. Is it possible to get 2 sets of strings that have exactly the same fault? (My guess is that since i bought them at the same time they may be from the same faulty batch)

2. Can a neck that is too straight cause intonation problems? (and wouldn't it cause it on all strings and not just two?)
#2
Quote by yekno
1. Is it possible to get 2 sets of strings that have exactly the same fault?

Yes, but doubtful.

Quote by yekno
2. Can a neck that is too straight cause intonation problems? (and wouldn't it cause it on all strings and not just two?)

Yes. I would say this is your culprit.

Also: it can't hurt to adjust your guitar to manufacturers suggestions anyway. Even if it doesn't solve this problem, it's still not a bad idea.
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