JBL GTO939 6×9 Coaxial Speakers: Workhorses For Your Ride

I had installed a pair of aftermarket speakers in my vehicle quite some time ago, and they had finally given worn out. I had been very happy with my previous speakers, so I was looking for something similar, or better, but within a strict budget. A friend told me about the JBL GTO939 speakers that he had recently installed. He said that they were within my budget but had the specifications of much higher-priced speakers. I ordered them and couldn’t wait to install them and try them for myself. Here’s what I found out.

Features of JBL GTO 939 6×9 Speakers


The tweeters in the JBL GTO939 are one of the speaker’s huge advantages over others in the same price range. The one-inch tweeters are made from a My/Ti, which is a Mylar and Titanium composite. They are designed to give more power handling, reduce distortion, and be more efficient. The distortion reduction is more evident in the mid-range frequencies, which is where most tracks have the vocals. This allows the JBL GTO939 to give you a much crisper, clearer sound than other speakers.


The GTO 930 speakers also have UniPivot. UniPivot is the system JBL designed that allows you to adjust the position of the tweeter so it is towards you. There is some after-installation customization required to adjust the tweeter dB output to your own preferences.’

Plus One Cone Technology

The JBL GTO939 speakers have JBL’s own Plus One cone technology. This is a cone that JBL has designed from special materials to be larger than average cones. A speaker produces sound by vibrating air, so the larger the cone, the more air it can vibrate. In these speakers, the Plus One cone helps produce better bass quality.


The JBL GTO939 speakers have a peak power handling of 300W per speaker and 600W for the pair. They have RMS power handling of 100W, and 200W per pair. The wattage in these speakers means that you can use them with your stock vehicle audio system, and you will notice an improved sound quality. If you upgrade your vehicle audio system to run them through an amplifier, then they really come into their own and produce incredible sound.


The sensitivity rating is more important than most people realize. The sensitivity rating shows how the speaker will respond to power, so the higher the rating, the better the response. The power needed to deliver the same volume decreases by around half with each 3 dB increase.

The JBL GTO939 speakers have a sensitivity rating of 94dB. This means that if you have set your volume and you’re using these speakers, you would use around 50 watts of power. In 91 dB speakers, you would need to use around 100 watts for the exact same volume level.


A huge part of the appeal of JBL GTO939 speakers is how easy they are to install. While some speakers require a specialist to install and maybe even modify your car, these do not. They were designed to replace stock OEM 6×9 speakers on almost any make and model of vehicle. You don’t need any special tools for installation, but if you’re trying to replace smaller speakers, then you will need to modify the space to allow the speaker to fit.

Who are these speakers designed for?

The JBL GTO939 speakers are designed with people in mind who:

  • Want great sound quality at a great price
  • Want easy installation
  • Have 6” x 9” speakers
  • Want to replace old and worn-out speakers
  • Want an aftermarket speaker upgrade
  • Want a full-range speaker

JBL is an audio company known for producing good-quality speakers. The JBL GTO939 speakers are full-range speakers that have been developed for crisp, clear sound. 

Frequently Asked Questions

Will these speakers fit in my vehicle?

The JBL GTO939 speakers are compatible with a huge range of vehicles. As a general rule, if your vehicle has 6” x 9” speakers, then these will work. They have a minimum mounting depth of 2”, which is quite shallow, so they can be installed into almost any vehicle without any additional modification.

Are they individual or a pair of speakers?

They are sold as a set of two speakers.

Is there any hardware?

No, you will need to find the hardware and connectors yourself. Make sure that all the connectors are the right size for your vehicle.

Do they have a warranty?

Yes, they come with a one-year warranty.


The JBL GTO939 3-way speakers are capable of power, performance, and quality. They are reasonably priced but with specifications that you might expect from more expensive speakers. They are easy to install but don’t come with any additional mounting hardware. Overall, they are great speakers that give a much better sound quality than the factory speakers in your car can. 

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