Metra’s MHY Stereo RCA Cable is what you’ll want to use for your subwoofers. A mid-tier cable that’s decent quality and priced well. I’m using these on my Dynaudio Core Subs. 

Sizes:

• 0.5 Meter

Specifications

• 24K Gold plated contact connectors
• Oversized connector pins
• Highly visible color marking
• Length: .5 meters