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Overview
Our Favorite 4 Channel Amplifer
The RZA1000.4 is the very best-sounding amplifier made specifically for Harley use. This amplifier has better speaker cone control at high volumes for better bass, and far better high frequency fidelity than other amplifiers. Natively compatible with factory Harley radios and aftermarket radios alike, the RZA1000.4 has a super wide range input (.41 to 10 volts) that is balanced so that it can accept anything from a standard line level RCA to a high voltage speaker level input directly from a factory radio. And it does this without the need for any noisy line levelers. This amplifier uses a far superior internal power supply to other amplifiers and can sustain extreme performance where other amplifiers just run out of gas and clip or drop in volume. This is a beast of an amplifier in a small footprint. This amplifier features a full chassis heat sink for more performance in a much smaller size package. The full chassis heat sink also allows for the amplifier to be mounted in any position and to keep cool even on the hottest summer days.
Fitment
- 1998 - 2013 Road Glide, 2 in the fairing without any modification to the bike. One fits between each fairing glove box and the inner fairing.
- 1998 - 2013 Street Glide and Electra Glide, 1 in the fairing without modification to the bike.
- 2014 and later Street Glide and Electra Glide, 1 easily fit on top of the radio without any modification to the bike.
- 2015 and later Road Glide, One fits under the radio.
- Additional Amplifiers can be added to the bags with a plug and play harness on all models.
Warranty
- 2 Years Limited
- 3 Years if installed by an authorized Velocity Speaker Design dealer
Features
Extreme Level Performance
Road Glide
Street Glide
- Full Chassis Heat Sink Design Can Be Mounted in Any Position
- Compact Design Fits All ‘14 and Later Fairings Without Any Modification
- Super Wide Range Signal Input Stage Is Compatible With Most Any Type of Analog Signal
- Made Specifically for Harley Applications
- Optimized for Velocity Speakers
- Flexible Design Is Perfect for Every Type of Speaker on a Bike Including Subwoofers, Bag Woofers, Mid Ranges, and Tweeters
- Onboard Active 12 db crossovers
Flash Your Bike Yourself and Be Sure That the Job Is Done Right
Our flash tool rental kit ships with all of the parts required to flash any Harley touring bike radio from 2014 - current year. The kit ships with a return shipping label for your convenience. After you are finished with the tool simply drop it in the mail and receive a full refund for your $200 deposit.
$120.00 Value!
Specifications
- 1,350 Watts Peak Power
- 4 x 275 Watts @ 2 Ohm RMS
- 4 x 150 Watts @ 4 Ohm RMS
- 2 x 550 Watts @ 4 Ohm Bridged RMS
- Crossover High/Low Pass 40hz - 400hz @ 12db
- Signal Input Range .41V - 10V Balanced High & Low Level
- RCA Input - Yes
- Speaker Level Input - Yes (over RCA connection)
- Efficiency 87% @ Full Power
- Remote Trigger 12V or Signal Sense
- Fuse Size 60A
- Power Cable 8 Gauge
Dimensions
- 9.1" L x 4.1 W x 1.54 H
What's Included
- RZA1000.4 Amplifier
- RCA Input Harness
- Speaker Output Harness
- Allen Wrench
Bread Pay

Snap Finance
Perfect way to pay within 100 days with no credit history required and no hard credit check. We cover the financing fees for you as long as you pay off your purchase within 100 days. So there are no hidden fees. Apply without any impact on your credit score.

100 Day same as cash financing
Shipping information
Most items ship in 24 hours (83% on average), some items do have a lead time due to manufacturing and tech oversight. All orders are processed and built in the order in which they are received. This allows our experts to review every order and check that it is correct for your specific bike. This means that sometimes you might have to wait a little longer to receive your order, but it’s always worth it!
Returns information
Returns are easy, simply contact us for a returns number and send your item to our returns centre for fast processing. We’ll get you a replacement or refund in a snap! You can find our refund policy here.
Lead Time
Some items have a longer lead time due to custom assemblies and requirements for tech oversight before shipping. We do our best to add estimated lead times directly to the product page for these items as well as inform our customers over the phone. All items in an order will generally ship together, so if you have one or more items that have longer lead times the other items in your order will usually ship out as soon as all parts are assembled and inspected. Please do not plan the ride of your life around the estimated shipping times of your stereo equipment :)

Easy Returns
Simply contact us for a return Authorization number and send your item to our returns center for fast processing. We’ll get you a replacement or refund in a snap! You can find our return policy here.

your part is guaranteed to fit
We test fit every part we sell on actual bikes in order to verify fitment on each moden, generation, and in each possible location. You can be sure that if we have stated that a part fits your bike, that it will, or your money back. You will find model, year, and location fitment details on most product pages.

We thoroughly test every part we sell on a real bike
There are a lot of parts out there that we refuse to sell. If it’s not up to our high standards, it never makes it to this website. We have parts that fit various budgets and levels of insanity, but all parts we carry are exceptional performers.

WE ARE FULLY AUTHORIZED RETAILERS FOR ALL BRANDS WE SELL
There are only a select few authorized online retailers for the brands we sell. Most all online retailers (even the really big ones) are not authorized at all! And the manufacturer’s warranty is void before you even get your items.

ordering from american hard bag is 100% safe and secure
You can rest easy - your personal details are never shared, sold, or rented to anyone either.