Mesa mk iv

I have a question about my Mark iv. I am currently running a combo together with a close-backed thiele extension cab. Both combo and can has ev speakers...sounds great. However I have the opportunity to purchase a rack mount kit for cheap. Would the sound be even better if I was to go this route, and run the amp through a close-backed 2x12 or 4x12?

You'd be better off posting this question in the vintage amp forum. That said, your Mark IV will almost always sound better through a 4X12, especially at low volume. Combos, no matter what speaker you have in them are bulky, so separating them is good idea.

Ok thanks...I have reposted in vintage amp forum!

I found the Mark IV to sound much better though a 412 cab, especially with RHY2 as it became useful with the 412. In combo format the RHY2 seemed a bit muddy or lacking. I had the Mark IVb combo and stuffed a FANE studio 12L in it. That was a huge improvement for use as a combo but still did not compare to the 412 loaded with V30 or one loaded with EVM12L (as I had both but converted the EVM to G12H75 Creambacks). I found the EV in the MKIV a bit sterile but not quite as sterile as it were in the Mark V combo. The V30 loaded 412 sounded the best with the MKIVb. I had considered converting the amp to a head but sold it for something else that I needed.

You can still drive a 412 with the combo if its load impedance is 8 ohms, you can even combine both combo (EV) with the 412 to add some depth. I have an open back extension cab with an EVM12L Black Label (not exactly a thiele) and may use it with my Roadster head and 412 cab to add a bit of depth and tight bass and a bit more top end as the EV can be bright and dark at the same time.