Hertz Stage 4 Ultimate Plug & Play Amp And Speaker Package with Modular Subwoofer Kit For 2023.5-Up Harley Davidson® CVO Road Glide Motorcycles

Can you hear your factory Harley speakers loud and clear at highway speeds? We didn’t think so. Tired of blowing those factory speakers just trying to hear them? Of course you are! These are common issues we hear ALL the time at Volunteer Audio. That’s why we’re here to deliver a sound experience that will truly blow you away. Can you really hear rear speakers when added to your bike? Absolutely! We get this question frequently, and the answer is a resounding YES. Here’s how we ensure you get the full benefit from your rear speakers:

• Optimal Speaker Positioning: For 6x9” speakers, we use custom cut-in kits that elevate the speakers higher in the lid. This not only saves space in your bag but also angles the speakers toward you, improving sound clarity. Most replacement lids don’t do this.
• Proper Powering: We make sure the rear speakers are properly powered so they’re loud enough to be heard even from behind.
• Balanced Sound: While front speakers will always be louder due to their direct orientation, rear speakers add a fuller, surround sound experience with enhanced mid-bass, creating a concert-like atmosphere.

Our Comprehensive Audio Upgrade Package Includes:

• Pre-Wired Amplifier: Gains and filters are adjusted perfectly for your factory Skyline OS Infotainment radio.
• Volunteer Audio HD-A2B8 Interface: Seamlessly integrates with your Harley Davidson, expertly tuned for Hertz systems.
• 1 Pair of Hertz SX165NEO 6.5” Upper Fairing Speakers: High-quality replacements for your factory speakers.
• 1 pair of Hertz SX690H NEO 6x9” Saddlebag Lid Speakers: Designed for clear sound and durability.
• Hertz Power/Ground Harness: Ensures reliable power and grounding.
• Lengthened Rear Backbone Harness and Modified T-Harness: Designed for an optimal fit and function.

Why Choose Volunteer Audio?

• Pre-Configured Kit: We handle all the prep work, including setting gains and filters, so you don’t have to. The kit arrives as close to finished as possible, making installation straightforward.
• Easy Installation: Includes mounting hardware and clear step-by-step videos. All you need to do is mount the amplifier, connect the wiring to under the seat and battery, and install the speakers.
• Lifetime Tech Support: We offer lifetime support for any items purchased from us, ensuring you have assistance whenever needed.

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American Hard Bag Modular Bass System

The American Hard Bag Modular Bass System is available with your choice of two premium 10-inch subwoofers.

Both have been extensively tested in this enclosure and both deliver exceptional performance. Neither is better. They simply have different personalities.

Velocity Performance Edition

Engineered Specifically for the American Hard Bag Enclosure

The Velocity 10-inch subwoofer wasn’t selected from an existing catalog.

It was engineered specifically for the American Hard Bag enclosure, creating a system where the driver, enclosure, and passive radiator were developed together as a complete acoustic package.

Rated at 300 Watts RMS and 600 Watts Maximum Power, the Velocity subwoofer features an injection-molded cone, Santoprene surround, oversized 56-ounce ferrite motor, and a 38 mm TIL voice coil to deliver exceptional punch, musicality, and long-term reliability.

If your playlist is filled with country, rock, blues, classic rock, or live recordings, the Velocity Performance Edition delivers outstanding impact and natural musical accuracy.

Ideal For: Country, Rock, Classic Rock, Southern Rock, Blues, and Live Recordings

Performance Highlights:

• 300 Watts RMS
• 600 Watts Maximum Power
• Frequency Response: 20-400 Hz
• Injection-Molded Cone
• Santoprene Surround
• 38 mm TIL Voice Coil
• 56 oz Ferrite Magnet

Expect:

• Tight, punchy bass
• Incredible kick drum impact
• Excellent bass guitar definition
• Fast transient response
• Natural, musical low frequencies

 

Hertz Reference Edition

Legendary Hertz Performance

The Hertz CS 250 S2 has earned a reputation for delivering exceptionally deep, controlled bass from compact enclosures, making it an ideal match for the American Hard Bag Modular Bass System.

Rated at 300 Watts RMS and 600 Watts Maximum Power, the CS 250 S2 utilizes a high-density ferrite motor, polypropylene cone, and precision-engineered suspension to reproduce the lowest octaves with outstanding authority and control.

If your music library includes hip-hop, rap, EDM, pop, or other bass-heavy genres, the Hertz Edition delivers the effortless low-frequency extension that brings those tracks to life.

Ideal For: Hip-Hop, Rap, EDM, Pop, R&B, and Bass-heavy playlists

Performance Highlights:

• 300 Watts RMS
• 600 Watts Maximum Power
• 2 Ohm Voice Coil
• Polypropylene Cone
• High-Density Ferrite Magnet
• 35 mm Voice Coil

Expect:

• Exceptional low-frequency extension
• Smooth, effortless bass reproduction
• Powerful sub-bass authority
• Outstanding musical accuracy

Volunteer Audio Recommendation

At Volunteer Audio, we’ve spent countless hours listening to, tuning, and testing both versions of this system.

Rather than offering a one-size-fits-all solution, we chose to offer two distinct subwoofer options because each excels with different styles of music.

If your playlist is primarily country, rock, blues, or live recordings, we generally recommend the Velocity Performance Edition. It delivers exceptional punch, outstanding musicality, and was engineered specifically for the American Hard Bag enclosure.

If your music leans toward hip-hop, rap, EDM, or you simply want to reproduce the deepest notes possible, we recommend the Hertz Reference Edition for its exceptional low-frequency extension.

There isn’t a better version.

There’s simply the version that’s better suited to the music you enjoy most.

If you’re unsure which system is right for you, give our team a call. We’ll be happy to help you choose the perfect setup for your motorcycle and your listening preferences.

Complete Kit Includes

• Left American Hard Bag modular enclosure
• Right American Hard Bag modular enclosure
• Two 10-inch subwoofers (Velocity or Hertz, depending on the model selected)
• Two integrated 8-inch passive radiators
• Plug-and-play amplifier-to-saddlebag wiring harness
• Saddlebag vent assemblies
• Precision vent cutting template
• Saddlebag vent installation hardware
• Complete mounting hardware
• All required installation components

Compatible With:

2023.5 and newer Harley-Davidson Touring motorcycles equipped with the redesigned saddlebags

Volunteer Audio Hertz A2B Stage 2 Systems

Volunteer Audio Hertz A2B Stage 4 Systems

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HD-A2B8 Amplifier Replacement Interface

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Hertz SP4.900 Amplifier

Our friends at Hertz have released a game changer for motorcycle audio! The Hertz SP4.900 amplifier offers a small footprint but huge output. It’s the most powerful amp available in its size, delivering 160W RMS @ 4Ω and 250W RMS @ 2Ω. With a remarkably low distortion rate of 0.02% THD, it’s the perfect choice for your motorcycle audio system. Technical Specs:

Output Nominal Power (RMS) @ 14.4 VDC, THD 1%:

4 Ch:

160 W x 4 (4Ω)

250 W x 4 (2Ω)

3 Ch:

160 W x 2 (4Ω) + 500 W x 1 (4Ω)

250 W x 2 (2Ω) + 500 W x 1 (4Ω)

2 Ch:

500 W x 2 (4Ω)

Total Power RMS: 1000 W

Dyno Specs:

Box rating: 160 watts at 4Ω, Dyno reads 173 watts at 4Ω

Box rating: 250 watts at 2Ω, Dyno reads 288 watts at 2Ω

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Ready to Elevate Your Ride?

At Volunteer Audio, we’re committed to providing you with an amazing sound system for your Harley Davidson. Our Stage 4 package is designed for top-notch performance and durability, transforming your motorcycle into a high-quality audio experience. Ready for a sound transformation? Let us help you get there!