The logo Arx uses Folio Extra Bold Font

The closest font you can get for the Arx logo is this font

Folio Extra Bold Font

About Folio Font Family
 

Designers: Konrad Friedrich Bauer, Walter Baum

Publisher: URW Type Foundry

Foundry: URW Type Foundry

Original Foundry: Bauersche Giesserei

Design Owner: URW Type Foundry

MyFonts debut: Mar 17, 2000
 

Download Folio Extra Bold Font