I know you posted back in May, and you may have already gotten an answer for your question. But just in case, I don't think your adenoids would affect your voice unless they were very much enlarged and cause your voice to sound nasal.
I had a tonsillectomy done not too long ago, in fact, I'm still recuperating from it. But I've been singing since a child and as I grew, my voice started having problems. I didn't have much resonance and power. I sounded muffled. It was then discovered that my then golf sized tonsils, were actually affecting the quality of the sound of my voice and it would cause me to double my effort in singing.
My voice is not 100% well as of now, but I'm hoping I can hear, feel and see the difference once I am well and fully recovered.
Really? Tonsils, eh? See, my voice sound sort of muffled to me when I hear it on tape but in my head when I sing it sounds alright...the effect is lesser when speaking as opposed to singing. It's always been like this, and I've never liked it. I refuse to sing in front of anyone even though I LOVE singing cause of it.
It sort of sounds throaty-nasal but not 100% nose nasal, if that makes any sense, and yeah I don't have much power/projection. I've never had lessons either though, so that could be because of that, who knows? *shrug* My tonsils have never been a problem though...nobody's ever commented on them being big or anything. I'm 27 now and you'd think they'd have noticed the few times I've had Tonsilitis in my life.
Also, it feels when I sing like I've got nasal congestion but I don't really...like, it feels like there's congestion or constriction right back deep in the nose/throat.
I don't think you should take out your tonsils if they are not a problem. Maybe you should see a voice teacher. They can tell you the root of the problem right away...especially if you are not using your voice as you should when singing.
It could be they way you are using your throat, or it could be something else. Don't consider surgery if you don't need it...although I've read some articles on the internet that some singers have chosen to remove their tonsils for their voices sake - specially projection. However, there are also articles about voices changing and ranges cut lower after surgery.
The safest way for you is to see a vocal teacher or even a doctor to check out your vocal chords.
I'll be hitting 3 weeks post surgery tomorrow and my voice is still throat-nasal. My throat gets tired when I talk a lot and I still get some pain and discomfort here and there. I've read that I should wait about 4 months before singing again.
Let me know how it all goes and what have you decided to do. In the mean time, take care.
Both tonsil and adenoid surgery are serious enough that it should not be used as a tool to change the sound of your voice. It's not like an elective cosmetic surgery. Unless there is a medical need for you to have them removed, it's really a very bad idea to do it just to try to change your voice.
I don't think any doctor worth his credentials would perform the surgery for you without a medical need.
And if you read the messages here from people who have had it done, you would see how bad the recovery is from this surgery. It's no picnic. It's probably the hardest thing I've ever had to go through in my life. Thankfully it's only a memory now, but it's one that I'm sure I'll never forget.