Will there be a dramatic difference?

Long ago I (briefly) had a Carver Sunfire Signature II 600 pushing Legacy Signature III speakers, and hated it. Replaced the Sunfire with a Parasound A21, and it was an absolutely massive improvement. Do it! 

Although I don't post much, I can tell you I am A life long (64 year old)carver user. All upgraded by Nelion Audio., I decided to upgrade a bit Got an ARC ref5se pre to replace the Carver pre. Wow!  Next got an ARC ref75se amp.next  More wow!! Then an Aurender A15 to replace Auralic Altair. Ok  thats it, I love tubes. Klipsch Forte III, GRresearch crossovers.

This upgrade sounds phenomenal. My point is having and listening to my Carver gear, which I had since the eighties which isn't the worst, and moving up the ladder was the best decision in my audio journey I ever made. So yes, do it!

I really appreciate the responses. And I am definitely going to make the jump. I do have one more question as far as difference in quality is concerned. Parasound also makes as. audiotroy posted the halo JC5. Anybody have an opinion on whether or not that would would be worth an extra $2000 on top of an already big improvement? $2000 seems like a lot considering the great reviews the A21+ already has.

"@audiotroy  we are a parasound dealer theA21 is a good amp you want a jc5 which is a much better amplifier then the 21"

I think this is accurate from what I know.

At the moment, I just can’t spend an extra two grand. I went ahead and ordered the A21+. In the future when I have some extra money, I will probably sell that one and upgrade. However, until then I’m sure the improvement from what I am currently running to the A21+ should be amazing and satisfy my listening needs for a little while anyway.