In all things guitars good quality fittings make all the difference. When you buy an acoustic guitar they are usually supplied with plastic string pegs. These work perfectly well, but if you want to improve the tone it is suggested that solid brass pegs are a worthwhile investment.
I am not sure when, but probably about 2004 when I bought my Yamaha FG423s I bought solid brass pegs to up the tone. I think I paid about £20 for them. I was impressed. I thought it made a vast difference to the tone and the appearance with neat inlaid M-o-P tops on the pegs.
I notice recently that the pegs are changing colour. I’m sure the M-o-P used to be white and that brass seems to be rubbing off! The colour of the M-o-P doesn’t bother me, but brass is brass it doesn’t rub off unless it’s plated and these were sold as ‘solid’ brass. Doh!