All evolution models have the word "evolution" written in gold lettering under the Ayre logo on the front panel. That is the foolproof way of knowing which model you have.
If you are still uncertain, the first letter of the serial number indicates the production version of the amp, so if you call Ayre and give them your serial number, they can confirm to you what you have.
If you are still uncertain, the first letter of the serial number indicates the production version of the amp, so if you call Ayre and give them your serial number, they can confirm to you what you have.