Some notes on Mic Settings
There are two, major determining factors on where you set the mic settings. First and foremost, the mic itself. Every brand of mic has a different pattern configuration, frequency response, range, etc...
Next, your vocal quality. Do you have a high pitched, mid range, lower range, bass? Are you a power singer, or do you have a soft, laid-back melodious voice. Is your voice a bit harsh, or do you sing the notes crisply and clearly. Your diction is important as well.
All of the above things come into play when setting up your mic. And, if you happen to change mics, well, the process begins anew.
Obviously, the highest quality mics will provide the singer with the best overall sound quality. These include the Samson Q7/8, Sennheiser E series, Crown CM-311A headset mic, and a few others fit into this category. To date, I have yet to use any of the Shure mics that I, personally, feel are top-notch. They may have been 35 years ago, but by today's standards, they usually don't make the grade.
One of the things that I try to emphasize is diction. There are so many singers out there that slur their words that it makes me want to cringe. There is a special school in Nashville, TN where diction for singers is taught, and some of the singing greats have attended this program, including Streisand, Elvis, and a large number of very popular country singers. It's that important.
Next, is voice control - again, this technique is taught at many community colleges in short vocal courses, most of which are non-credit. To get an idea about what voice control really consists of, listen to any radio newscaster and you'll understand what I'm talking about. His or her levels are very consistent, their diction is perfect, and they know how to place emphasis on a word without raising their voice level. This same voice control is a very important aspect of being a successful singer.
Now, as the actual settings, this will, obviously, be quite subjective. I suggest to everyone, sing a song dry, no effects and record it using a high-quality digital recorder, or the keyboard's onboard recorder. Then play it back and have your wife, or a friend listen to it and assess your vocal qualities. After more than a half century of being married to the same woman, she has absolutely no qualms about letting me know if she likes, or dislikes what she hears, and why.
Now, sing and record the same song, after changing some of the mic settings, adjusting the EQ, adding a bit of reverb, etc... Then play it back, and again, have someone else note the changes and make the assessments. You'll be amazed at the difference just a small amount of adjustments can make.
Now, if you don't have a quality, basic, singing voice to begin with, there is nothing that can be done to change this other than taking some voice lessons at the local community college. Most of the courses are designed to teach you the basics, such as voice control, proper breath control, holding a note without wavering, timing, and a few other important aspects. Usually, at the end of the course, you will be evaluated by an audience consisting of other students, and often a large number of folks that just want to enjoy the performances at no charge. When I went through this course, I was amazed when about 500 people showed up for the final performances. For me, standing in front of 500 people was a piece of cake - I've never experienced stage fright. However, there wee some student in the class of 35 singers, that had horrific stage fright and really panicked. I took the Voice And Articulation course 25 years ago, the instructor was a well known jazz singer, and I really enjoyed it. It was a 6 week, 3 night a week course that cost me about $100 back then. It was well worth it and helped me a lot.
Hope this helps,