I've just finished setting up my first system. I had the pre-amp and amplifier already. The Onkyo P-301 and Onkyo M-501. For speakers I built a pair of TriTrix MTM transmission lines. Here's a link:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-702. I setup the components and speakers once I was done building them and they sounded great playing music from a digital source. Definitely no fuzz / distortion there. A few days ago my Pro-Ject Debut Carbon came in the mail. I was very careful setting it up. Practiced balancing the tone arm 3 or 4 times to make sure I was confident in the way I was doing it. Made sure the anti-skating weight was setup properly. I also am completely confident that the needle never touched anything until I lowered it onto vinyl for the first time with the tonearm lever. I have not confirmed that the surface the turntable is on is completely level but I am certain it is close. I also have not "Adjusted the azimuth" which if I read the instructions correctly controls the (borrowing from flight dynamics) "roll" of the needle in relation to the groove of the record. Even using a magnifying glass the needle appears perpendicular to the record.
I purchased a sealed copy of (is that proper vinyl terminology?) Dark Side of the Moon to test out my new toy with. I lowered the tonearm using the lever and sat in my chair hoping for the best. Everything was sounding great until mid-way through "Breathe" I started noticing the vocals were fuzzy and distorted. Not bad, but definitely noticable. All the instruments seemed to be coming through fine but it made me wonder if it was just more noticable in the singing. I adjusted the volume and the problem seemed worse at lower volumes. This makes me wonder if maybe the problem is some kind of voltage or impadence mismatch in the component chain. Or maybe the phono input in my pre-amp is just bad? This is possible as this component along with the amplifier are older and they have been in and out of storage a few times. I'm almost certain I setup the turntable properly. How likely is it that a slightly unlevel surface could cause this?
What steps should I take to diagnose this issue?