Dynaco ST-70 and Magneplanar 1.6QR

By gain do you mean volume?
I got more volume out of my old dyan-70 by getting rid of the lamp cord power 'cable' and hard wiring a 14 gauge cord with a heavy duty plug.
No doubt,it played louder.
Also,make sure your output tubes are good and dont have high hours on them.The Svetlana EL-34 is a great tube and can give you a cleaner presentaion...clean = increased percieved volume. Also,Have you tried the 4ohm tap?

The Stereo 70 will run out of steam quickly with the 1.6's, I had Rogue Magnum 120's (120 watts) and they were not enough power for my taste.

My MG 1.6 sound much better with a 350 watt Adcom amp than with a 100 watt Adcom amp having similar specs except for power. The message is clear...get more watts.

Maggies need much more power. You could try a good powered sub. If you run from the pre-amp to the sub to the amp, you can filter out all signals below a certain level (100hz?) which will greatly alleviate the strain on the 70. According to Janis Subwoofers, if you eliminate all bass below 100hz, you effectively quadrupal the power available to the speakers!

Thanks for all the great advice. I am a novice in the hi fi area, but I realize that I am plummeting into the rabbit hole fast. ... I got the Maggie 1.6, loving the open sound, but felt that they needed some warmth, and therefore combined them with the Dyna - 70. It actually sounds good, as long as the music is not to demanding, and kept low...

So here is my probem I guess, is there any tube amp I could afford that provides 100W per channel or more? , ( would that do the trick?)
budget is about 1k....

alternatively, on the same budget, is there a solid state amp with warmth...? , again, thanks alot for all your advice..