EQ Pedals with Marshall Artist 3203 Questions

[Charvel1975]

Hey guys last night I hooked up my Marshall Artist to my Mesa 2x12 Tverb cab: amp set to 8 ohms to 16 ohm mono input on cab and tried using my MXR 6 band eq pedal I picked up not long ago thru the front end of amp first then thru the effects loop but in either of them I kept getting loud hiss and noisy feedback, even on the clean channel?

I haven't tried the other eq pedal I picked up yet, a danelectro fish n chips 7 band eq pedal but I wonder if I'm gonna get the same result? I'm still contemplating on picking up either a used Bogner Ecstasy Red pedal or a used Blackstar HT Dual 2 channel preamp pedal but I'm wondering because the amp doesn't have the C13 mod if I'll still be able to have a good clean channel and a really good distorted tone for drop B and also for standard tuning for playing other styles ie: hard rock/classic rock/80's metal/hair metal etc?

 

[Mudder]

You got his through both front of amp and in the loop? No hiss without the pedal? If that's the case then I'd start with different cables, then a different pedal.

 

[Charvel1975]

You got his through both front of amp and in the loop? No hiss without the pedal? If that's the case then I'd start with different cables, then a different pedal.

The day that the MXR & Danelectro eq pedals showed up I tried each one thru the effects loop and thru the front end of my Mesa Tverb head and I didn't notice any noise or hiss from the Danelectro but the MXR I did although the hiss wasn't nearly as bad as thru the Marshall Artist 3203 head not to mention the feedback when using with the Marshall. Now I may have been running wrong ohms, the Marshall head only has a 4 or 8 ohm selector switch and the stock celestion vintage 30's in the Tverb cab are 16 ohms. The jack pate on the cab can be used for the following configurations:
•4 ohm mono
•8 ohm left + 8 ohm right stereo
•8 ohm left only mono
•8 ohm right only mono
•16 ohm mono

So I hooked up the Marshall head to the Tverb cab again and tried both EQ pedals again....I ran the head at 4 ohms into the mono 4 of the cab and that part I knew would be right. Other thing I didn't think about was the effects loop, the Mesa for sure has a parallel loop where I think I read online my Marshall Artist 3203 has a Series loop so that could be the problem there?