Yeah that's all. I'll look more closely during practice tonight to see if the nail is too long. I
I've been playing with three plucking fingers for years (index, middle and ring). About a year ago, I noticed the same problem you've described: my middle finger tone was much brighter than my index finger tone. For me, evening out the tone was accomplished by making sure my finger. aims were the same length. Longer nail = brighter tone, and 1/8" difference in length was a lot.
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