RPM870: How To Set Up A Powered Subwoofer

Introduction

The Rockville RPM 870 mixer allows you to expand your setup by adding powered subwoofers or additional speakers. This guide will walk you through connecting a subwoofer to your RPM 870 mixer using an XLR cable or 1/4" TRS cable, ensuring you get the best low-end response for your sound system.

Step 1: Gather Your Equipment

Before starting, make sure you have the following:

• Rockville RPM 870 mixer
• Powered subwoofer
• XLR cable (preferred) or 1/4" TRS cable (alternative)
• Power cables for the subwoofer and mixer

Step 2: Connecting the Subwoofer to the Mixer

1. Power off both the mixer and subwoofer before making any connections.
2. Choose your output type:
   • If using an XLR cable:
     • Plug the male end of the XLR cable into the left XLR input on your subwoofer.
     • Plug the other end into the left XLR output on your RPM 870 mixer.
   • If using a 1/4" TRS (balanced) cable:
     • Connect one end to the 1/4" output on the mixer.
     • Plug the other end into the 1/4" input on the subwoofer.

✔ These steps apply when setting up a single subwoofer.

Step 3: Connecting a Second Subwoofer (Optional)

If you want to connect two subwoofers, follow these steps:

1. Use the right XLR output on your RPM 870 mixer.
2. Connect another XLR cable from the right XLR output to the right input on your second subwoofer.

✔ This setup provides stereo low-frequency output for an even sound distribution.

Step 4: Powering On and Adjusting the Subwoofer Settings

1. Turn on the subwoofer after all connections are secured.
2. Adjust the volume on the subwoofer to match your main speakers.
3. Set the crossover frequency:
   • If your subwoofer has a crossover knob, set it to 80Hz–120Hz depending on the size of your main speakers.
   • If using large speakers, set the crossover lower (e.g., 80Hz).
   • If using smaller speakers, set the crossover higher (e.g., 100Hz–120Hz).

Step 5: Test Your Setup

1. Play audio through the mixer.
2. Slowly increase the volume of the subwoofer while listening for a balanced sound.
3. Ensure the bass is deep and clear, without overpowering the main speakers.

✔ The subwoofer should enhance the low-end without muddying the mix.

Expanding Your System with More Speakers

• You can add more powered speakers using the same XLR or 1/4” outputs.
• If using passive speakers, you will need an amplifier to power them.

Troubleshooting & FAQs

Q: Why isn’t my subwoofer producing sound?

✔ Make sure the mixer’s master volume is up and sending a signal.

✔ Check if the subwoofer’s volume is turned up.

✔ Ensure the XLR or 1/4" cable is securely connected.

Q: What crossover setting should I use?

✔ Try 80Hz–120Hz depending on your main speakers.

✔ Adjust until the bass blends well with the mids and highs.

Q: Can I connect multiple subwoofers?

✔ Yes, by using both the left and right XLR outputs.

Conclusion

Setting up a subwoofer with your Rockville RPM 870 mixer is simple and effective for enhancing your sound system. Whether you're adding one or multiple subwoofers, this guide ensures you get deep, balanced bass with your setup.