top of page

How To Seal 6x9s In Harley Speaker Lids The Right Way

Tuning is dramatically affected when adding sealed 6x9 enclosures. Read and understand the following information to get the killer results you are looking for. The IP-6x9-V-SEALED 6x9 enclosures are designed specifically for 6x9 speakers in Harley speaker lids. These enclosures (sometimes referred to as baffles) allow you to dedicate the lion's share of air volume inside of your bags to your bag woofers instead of the 6x9s while also allowing you to take full advantage of your 6x9s high-power midrange abilities. 6x9s are inherently more powerful and have mechanical advantages over other types of midrange speakers such as 6.5"s due to their much larger cone surface area and more capable motor structures.

The Key To Performance

What makes the Velocity sealed backs different from 6x9 baffles from other companies is that they are rigid, airtight, and add no extra footprint to the speakers. If your speakers fit without the enclosures they will also fit with the enclosures. The real key to performance is in understanding that by using 6x9 baffles you are shifting the frequency range of both your 6x9s as well as your bag woofers. Your bag woofers will need to produce sound at frequencies at least as high as the high pass crossover point of your 6x9s (around 200 to 400hz). In many cases, it is even advisable to set your woofer low pass crossover even higher or not use it at all. You need both your bag woofers and your 6x9s to work together to get the best performance.

Know What To Expect

What It Does Do

  • Isolates the 6x9 back wave from any other speakers in the saddlebag, eliminating any enclosure interaction with other speakers in the bag.

  • Makes ported bags a viable option. Tuned ported bags need as much air space as you can give them in order to achieve low frequency extension and the level of efficiency needed to be heard on a bike. By isolating the 6x9 air space and trading off 6x9 air volume for bag woofer air volume you are able to gain a lot more dedicated air volume for your larger bag woofers that can make much better use of that space.

  • Makes some 6x9s work with bag woofers. Some otherwise great 6x9s can not reasonably share air space with a powerful bag woofer due to the 6x9's less capable suspension, motor power, and cone rigidity. This is the case with most coax horn style 6x9s. The lightweight speaker cones and short throw suspensions are engineered for high midrange power and can not endure the forces exerted by a large woofer at low frequencies.

  • Raises the speaker's resonant frequency and reduces the speaker's low-frequency response. This is generally a desirable tradeoff when you consider the gain and low-frequency extension that can now be achieved from your larger bag woofers.

  • Faster transient response and increased damping. Increased air pressure behind the 6x9, can have the desirable effect of tighter and more accurate cone control. Especially at extreme volume levels.

  • Increased efficiency around the speaker's new elevated resonant frequency. This can often be used to your advantage when tuning to achieve a very snappy and live sound.

What It Does Not Do

  • Increase bass from the 6x9

  • Make the 6x9 perform better when not used in conjunction with other larger bag woofers. Sealed-back 6x9 enclosures should never be used without other woofers in the bags to produce low frequency

Installation Details


  • Use the included foam speaker gasket to seal the 6x9s into the enclosures.

  • Route the speaker wire connections through the included rubber grommet.

  • Use a small amount of silicone to seal the wire into the grommet.

  • Use proper washers on your speaker screws between the screw head and the 6x9 enclosure so that the screw head does not dig into the enclosure. Also the washers will help spread the load over a larger area.

  • Properly align the speaker screws so that they are not at an angle.


  • Over-tighten the speaker screws.Constructed from a highly rigid polymer, Velocity baffles resist surface vibration and resonance modes, ensuring your 6x9 speakers do not interact with other speakers in the bag. This rigid polymer is not engineered to endure twisting and bending from overtightened screw heads. Hand tighten and use common sense.

About the Grommet

The grommet can be drilled for your wire to pass through. If your wire harness has a connector(s) already on it then you can also slice down one side of the grommet with a razor knife and split it open to insert the wire harness. Always fill the center of the grommet with silicone after seating the wire harness. You want to make sure that the enclosure is 100% airtight.

IMPORTANT! Crossover Frequency Settings

The Info

6x9s should always be high passed in a bike system but that is twice as true when installing them into small sealed enclosures. If you fail to set your high pass crossover frequency correctly you will end up subjecting your 6x9 speakers to a very high level of voice coil heat. The dramatic increase of air pressure behind the speaker cone reduces the cone travel and generates heat in the voice coil when the crossover frequency is set too low. The solution is to raise the high pass crossover frequency to a point that the speaker is no longer attempting to produce frequencies below its new usable range. The exact crossover frequency will depend on your particular speaker.

Crossover Frequency Setting Procedure (by ear)

Play a music selection with the following properties. High-quality recording on a USB drive (not from your phone). You should download your recordings from a quality source such as Never use Youtube, Pandora, or any streaming service. Do not use your phone. Your phone is fine for listening but not for setup.Choose test music: Select a high-quality audio track that you're familiar with that has a good mix of frequencies, especially in the bass and midrange region. This will help you identify how the crossover is affecting the sound.Follow the steps below

The Steps

  1. Mute all other speakers other than tweeters if your 6x9s use outboard tweeters.

  2. Set your crossover to high-pass mode

  3. Set your crossover to 24db if it has a selectable slope

  4. Set your crossover to Linkwitz Riely if your crossover has a selectable characteristic

  5. Temporarily set your high-pass crossover frequency to 150hz

  6. Listen and adjust: Play your test music at a moderate volume and listen carefully to the sound. Gradually increase the crossover frequency while paying attention to the bass and midrange balance. As you raise the crossover frequency, you will notice less bass being produced by the speakers.

  7. Find the right balance: The 6x9s will have a sharp rise in the range between 200 and 400hz. You want your crossover frequency to be above this rise in response in order to eliminate that fluctuation. Settle on a frequency above the point where the 6x9s sound funky due to the small enclosure. They will lack bass but we will address that next. The idea here is to set the crossover frequency high enough that the 6x9 enclosure size is not relevant and no longer affects the 6x9s response.

  8. Unmute the bag woofers and listen to the larger bag woofers and the 6x9s as a group.

  9. Adjust the amplifier gain: Gain both the 6x9s and the bag woofers so that their levels are complementary. This is a temporary gain adjustment and will not be your final gain. This gain setting is only for the purpose of setting the crossover frequency.

  10. Adjust the bag woofer low pass crossover frequency to the same frequency as the 6x9 high pass frequency. Adjust from there by ear. You can not hurt the bag woofers by choosing too high of a low pass frequency. Experiment with no lowpass on the bag woofers at all.

  11. Always use your DSPs phase feature to see if the bag woofers sound best with the phase inverted from the 6x9s. You might be surprised at the result.


  1. Properly flash your radio first. We only recommend the Rockford flash. We do not recommend any flash that yields a flat output. The Rockford flash retains the factory dynamic EQ which makes systems sound much more powerful at all volume levels.

  2. Use your DSP master volume to reduce the volume level of all of your speakers to a level that is kind to your ears while the factory radio is at one notch down from 100% volume. Do this because the factory dynamic EQ adds a ton of bass boost when the radio is at less than full volume, which will dramatically affect the frequency response of all of your speakers. The Dynamc EQ is a very good thing but must be taken into account when setting the EQ and crossovers. At one notch down from 100% radio volume the dynamic EQ is essentially nulled out. So that is where you want your volume when making crossover adjustments. Tip: Never attempt critical listening tests at high speaker output levels. You can not make reasonable assessments at extreme SPL levels.

Clipping is not an issue with factory Harley radios (2014 and later) because these radios have an active compressor/limiter built into them that does not allow them to clip. If you run into distortion/clipping with the radio at or near full volume, it will be due to your DSP being overdriven. All DSPs used in Harley applications should be able to handle the full output signal of your radio. If your DSP cannot handle the full radio output signal, you do not have a proper DSP for the job. Check to make sure your DSP is properly set up for high-level input before concluding that the DSP is not correct for the job.

View PDF

Sealed Backs for 6x9s IP-6x9-V-Sealed

This comprehensive guide provides step-by-step instructions, as well as helpful tips and tricks, to ensure a secure and water-resistant fit. With easy-to-follow instructions and detailed photos, this page is the ultimate resource for anyone looking to upgrade their Harley's audio system.

bottom of page