How to Wire High Level Input on an Amp: A Step-by-Step Guide

Wiring high-level input on an amplifier can be a daunting task for beginners in the audio world. However, with a step-by-step guide, even those with minimal experience can successfully accomplish this task. High-level input, also known as speaker-level input, allows you to connect your amplifier to a factory or aftermarket stereo system that doesn’t have RCA outputs. This article aims to provide a comprehensive and easy-to-follow guide on how to wire high-level input on an amp, ensuring optimal sound quality and a seamless integration with your audio setup.

The first step in wiring high-level input on an amp is to determine the type of output your stereo system has. This can be either a factory head unit or an aftermarket stereo. Different systems require different connection methods, and understanding your system’s output is crucial for a successful wiring process. Additionally, various amplifiers have different high-level input options, so it’s essential to choose an amplifier that suits your specific needs and preferences. By following this step-by-step guide, you’ll be able to connect your amplifier and stereo system seamlessly, providing you with enhanced audio performance and an enjoyable listening experience.

Understanding High Level Inputs: What Are They And When To Use Them

High level inputs, also known as speaker-level inputs, are a feature found on amplifiers that allow you to connect the amplifier to a source unit without the need for RCA cables. This is particularly useful when you’re working with factory-installed or aftermarket head units that do not have RCA outputs.

When to use high level inputs? There are several scenarios where high level inputs come in handy. For example, if you want to keep your factory head unit in your car but still want to upgrade your sound system, using high level inputs allows you to connect the amplifier to the existing speaker wiring. This eliminates the need for costly and time-consuming rewiring.

Additionally, high level inputs are ideal for connecting amplifiers to head units that only have speaker outputs. By using high level inputs, you can still enjoy the benefits of an amplifier’s power and improved sound quality.

Understanding how to wire high level inputs is essential for anyone looking to upgrade their car audio system while retaining the factory head unit or dealing with speaker outputs only. In the following steps, we will guide you through the process of wiring high level inputs on an amplifier.

Equipment Required For Wiring High Level Inputs On An Amp

When it comes to wiring high level inputs on an amp, having the right equipment is crucial to ensure a seamless installation process and optimal sound quality. Here is a list of essential tools and materials you will need:

1. Amplifier: Make sure you have the appropriate amplifier that supports high level inputs. Check the specifications or user manual to confirm compatibility.

2. Head unit or source unit: This is the device that will provide the audio signal to your amplifier. It can be a car stereo, DVD player, or any other audio source.

3. Speaker wires: Use high-quality, properly sized speaker wires to connect the speakers to the amplifier. The gauge of the wire will depend on the power requirements of your audio system.

4. Wire stripper: A wire stripper is necessary to remove the insulation from the speaker wires, exposing the bare metal for connection.

5. Wire crimpers or soldering iron: Depending on your preference, you can either crimp the wires together using wire crimpers or solder the connections with a soldering iron for a more secure and reliable connection.

6. Electrical tape or heat shrink tubing: To protect and insulate the connections from potential damage or short circuits, wrap them with electrical tape or use heat shrink tubing.

By having all these equipment ready, you can ensure a successful and professional high level input wiring on your amplifier.

3. Step 1: Locating the High Level Input Terminals on Your Amplifier

In this step, we will guide you on how to locate the high level input terminals on your amplifier. Before starting the wiring process, it is crucial to find these terminals to ensure a proper connection. The location of these input terminals may vary depending on the amplifier model, so it’s essential to refer to your amplifier’s manual for specific instructions.

Typically, the high level input terminals are located on the back panel of the amplifier. Look for a set of RCA-style jacks or spring clips labeled as “High Level Inputs” or “Speaker Level Inputs.” Some amplifiers may also have a dedicated high level input harness that needs to be connected.

To locate these terminals, follow these steps:

1. Turn off your amplifier and unplug it from the power source.
2. Examine the back panel of the amplifier and look for the input section.
3. Search for the terminals labeled specifically for high level inputs, usually distinguished from other inputs.
4. Take note of the color-coding or labeling for each terminal; they may be labeled “Left” and “Right” or with a positive (+) and negative (-) symbol.

Once you have successfully located the high level input terminals, you can proceed to the next steps of wiring your amplifier for high level inputs.

Step 2: Preparing The Speaker-Level Input Wires For Connection

Before connecting the speaker-level input wires to your amplifier, it is essential to prepare them properly. This step ensures a secure and reliable connection, which is crucial for optimal audio performance.

To prepare the speaker-level input wires:
1. Start by stripping the insulation off the ends of the wires. Use a wire stripper or a sharp knife to carefully remove about 1/4 inch of insulation.
2. After stripping, twist the exposed wire strands tightly together. This prevents fraying and ensures a solid connection.
3. If you notice any damaged or corroded wire, it is recommended to replace it with a new one. Damaged wires can negatively affect the audio quality or cause connectivity issues.

Once the wires are properly prepared, they are ready to be connected to your amplifier. Remember to double-check the polarity and ensure that you connect the positive (+) and negative (-) wires correctly. By following these steps, you can ensure a clean and secure connection for your high-level input wiring.

Step 3: Connecting The Speaker-Level Input Wires To The Amplifier

Connecting the speaker-level input wires to the amplifier is a crucial step in wiring high level inputs on an amp. Follow these steps to ensure a proper connection:

1. Strip the ends of the speaker-level input wires: Use a wire stripper to remove about 1/2 inch of insulation from the ends of the wires that will connect to the amplifier. This will expose the bare wire for connection.

2. Identify the positive and negative terminals: Most speaker-level input wires are color-coded, with one wire being positive (+) and the other negative (-). It’s important to correctly identify these terminals to ensure proper functionality.

3. Connect the wires to the amplifier: Take the positive wire (+) and connect it to the corresponding positive terminal on the amplifier. Use a small screwdriver or an appropriate connector to secure the wire in place. Repeat the process for the negative wire (-), connecting it to the corresponding negative terminal.

4. Double-check the connections: Once all the wires are connected, double-check their polarity and make sure they are securely fastened. Loose connections can result in poor sound quality or even damage to the amplifier.

By following these steps, you will successfully connect the speaker-level input wires to your amplifier and be one step closer to enjoying high-quality audio in your vehicle or home.

Step 4: Testing And Troubleshooting The High Level Input Wiring

After successfully connecting the speaker-level input wires to your amplifier, it is crucial to perform a thorough testing and troubleshooting process. This step ensures that your high level input wiring is functioning properly and delivers the desired sound quality.

To test the wiring, start by playing some audio through the amplifier using the connected sources. Listen carefully for any distortions, noise, or imbalance in the sound output. If you detect any issues, it’s time to troubleshoot.

Begin troubleshooting by double-checking all the connections. Make sure the speaker-level input wires are firmly connected to both the amplifier and the source unit. Check for loose wires or faulty connections that might be causing the problem. Also, examine the wires for any damage or fraying that could affect the signal transfer.

If the connections seem fine, try swapping the speaker-level input wires to check if the issue lies with a specific wire. If the problem persists, you may need to experiment with adjusting the gain settings on your amplifier. Changing the gain levels can help eliminate any sound imbalances or distortions.

In case troubleshooting doesn’t resolve the issue, it is advisable to consult a professional or contact the manufacturer for further assistance. Remember, a properly wired high level input ensures optimal performance and sound quality from your amplifier setup.


1. What is high level input on an amp?

High level input on an amp refers to a way of connecting the amplifier to the audio source using speaker wire connections instead of RCA cables. This method allows you to connect the amp directly to the speaker outputs of a car stereo or any other audio device without preamp outputs.

2. Why would I need to wire high level input on an amp?

Wiring high level input on an amp is necessary when your audio source doesn’t have preamp outputs or if you prefer to use the speaker outputs for connection. This is common in car audio installations where the stock stereo may not have RCA outputs.

3. What are the benefits of using high level input?

Using high level input allows you to tap directly into the speaker signal, bypassing any additional signal processing that may degrade the audio quality. Additionally, it eliminates the need for a line output converter, making the installation simpler and more cost-effective.

4. How do I wire high level input on an amp?

To wire high level input on an amp, start by identifying the positive and negative speaker wires coming from your audio source. Strip a small section of insulation from each wire, then connect the positive wire to the amp’s positive high level input terminal and the negative wire to the negative terminal. Repeat this process for each channel you want to connect.

5. Are there any precautions to consider when wiring high level input?

When wiring high level input, it’s important to ensure that the amp is compatible with this type of connection. Some amps have dedicated high level input terminals, while others may require special adapters. Additionally, make sure to double-check the polarity of the speaker wires to avoid any phase cancellation issues.


In conclusion, wiring high-level input on an amp may seem daunting at first, but with this step-by-step guide, it becomes a straightforward process. Whether you’re looking to connect your amp to a factory stereo or replace your head unit with an aftermarket one, these instructions will help you achieve optimal sound quality and performance.

Additionally, understanding the different types of high-level input connections and their benefits allows you to make an informed decision when setting up your system. By following these steps and ensuring proper grounding and signal management, you can enjoy powerful and clean sound reproduction with your high-level input amp.

Leave a Comment