I am currently using two Retro 30s in a 2x12 cab, and two ET65s in another one, with the Retros on top, and the sound is amazing. The ET65s are great, but the real reason I use two of them mixed with two Retro 30s is because I don't have two more Retro 30s. Retro 30s do everything for me beautifully. I use the Line 6 Spider Valve II 100 watt head, and these Retros do everything from brutal metal to jazz. I will be picking up two more and using a quad of Retros...no other speaker necessary. The first thing I tell anybody when they ask about speakers is try the Retros first...I really believe it's the last speaker I will ever need. Great job WGS.
Im running a 2x12 with a ET65/Retro30 combo. The retro replaced a Sheffield speaker out of a 6505 112. There are no words to explain how much better it sounds with the additon of the Retro 30. The Sheffiled speaker was a piece of garbage, but the Retro and ET65 are just amazing speakers as well.
I'm building a 2x12 combo that essentially has a 2-channel hot-rodded version of a JCM800 preamp mated to the power amp section like a JTM45, with tweaks of course. I decided to go with the Retro30s in this combo and it is by far the best speaker I've ever heard!
I'm glad you mention having replaced your Sheffields with Retros and how much better they sound. I have an old Peavey cabinet from the early 90s with Sheffields in it and have always felt it was too muddy sounding and not enough articulation. I don't know what I haven't thought about trying the Retros in it before but I think you're on to something! So that will be my next speaker swap!