What Bass Blocker should I buy?

Bass blockers come in different sizes, determined by the impedance and frequency cut-off points. In general, the smaller the speaker, the less their ability to play lower frequency sounds. Audiophiles will find the speaker specifications, find the impedance and frequency range of the speaker, and do the math to come up with the ideal frequency cut-off point for that speaker. But for most car speakers, that kind of data is usually impossible to find. Lacking this kind of data, finding a good bass blocker for the speakers installed in your car, may take some experimentation. Here's a list of the common sizes you can use as a guide, assuming 4 ohm speakers: Up to 3.5" Speaker: Bass blocker 0 - 2.8kHz 5.25" Speaker: Bass blocker 0 - 800Hz 6.5" Speaker: Bass blocker 0 - 600Hz 6x9 Speaker: Bass blocker 0 - 300Hz

How To Install A Bass Blocker For Your Car Speaker

I had just turned up the volume on my car stereo when I heard a loud pop. The sound was so intense that it made me jump, and then the door speaker buzzed loudly and started irritatingly humming as I tried to tune out what sounded like an angry bee.

I blew my car speaker. If you drive long enough, you’re bound to do the same, especially if you’re running an amp or factory speaker.

The way to prevent this from happening is by installing a bass blocker. But how do I do that? We’ll show you how to install bass blockers for your car speaker.

Tools Needed to Install Bass Blockers

Installing a bass blocker isn’t difficult, but it will require working with your car’s electrical system. It doesn’t matter if you have a factory or aftermarket head unit, as you won’t need to remove the head unit anyways or modify the factory wiring harness it’s connected to.

List of Tools Needed

Crimping tool
Wire stripper and cutter
Screwdriver set
Male and Female spade connectors
Door Trim Removal kit (with spare clips because I always break one!)
Electrical tape
Your Cars manual

Image	Product	Features	Price
Wire Crimper	Channellock Wire Crimping Tool	Cuts and crimps 10-22 AWG wire Crimps both insulated and non-insulated solderless connections and terminals Laser heat-treated edges last longer High-carbon C1080 steel Made in the USA	Check Price
Wire Stripper & Cutter	Channellock 958 Wire Stripper and Cutter	PRECISION cutting edges cleanly cut and strip AWG 10-20 wire DURABLE coiled spring reduce hand fatigue LEAN pliers nose pulls and loops wire LASER-ETCHED gauge indicators LOCK for safe storage CHANNELLOCK BLUE grips for comfort 100% MADE IN USA	Check Price
Screwdriver Set	CRAFTSMAN Screwdriver Set, Assorted, 12-Piece (CMHT65044)	Alloy-steel blades are heat-treated for strength and durability Coated with a satin-nickel finish Comfort Optimized handle for high & low torque applications Full Lifetime Warranty, refer to “Warranty & Support” section below for full details	Check Price
Spade Connector Kit	Qibaok Spade Connector Kit	Wire Range: AWG 22-16 (Red), AWG 16-14 (Blue), AWG 12-10 (Yellow) 840PCS Wire Terminals Strong Copper Barrel to hold the wire tight when crimped.	Check Price
Door Trim Removal Kit	GOOACC 240PCS Trim Kit	UNIVERSAL FIT KIT – 12 popular size, fitting for door trim, radiator shield yoke, fender, bumper and splash shield retainers replacement for Ford, GM, Chrysler, Toyota, Honda and more EASY STORAGE – Comes with a plastic box with 12 compartments for organized storage	Check Price
Electrical Tape	Wapodeai 3PCS Electrical Tape	Premium performance Each roll is 49 ft long and 0.62 in wide Strong durability	Check Price

General Preparation

Remove Power

It’s safest to remove power from your vehicle before you work on it. I recommend disconnecting the car battery.

Look in the Owner’s manual and find the location for the car battery. Most of the time it will be under the hood of the car, but some car’s like BMW’s, will have the battery in the trunk.

Remove the black cable connected to the negative battery terminal. This will effectively remove power from your vehicle and you can safely work on it now.

Locate Speakers

Refer to the Owners manual or a repair manual and find the locations of the speakers in your car. Usually there are four, one in each door, and they’ll be 3″ or larger.

Some cars may have component speakers, usually a speaker in the door connected to a tweeter located higher up in the door or in the dash. If this is what you have, usually accessing the door speaker is the goal and the steps will be the same.

Gain Access To Speaker

You need access to the rear of the speaker where the wiring connects to the speaker terminals. They’re normally found at the rear of each speaker. This is necessary to be able to install the Bass Blockers.

In most situations you’ll need to remove the door card (also called door panel) using a nylon pry bar to pop the plastic rivets on the backside of the door card.

If it has a plastic membrane, it’s usually attached with a sticky putty like substance that can be re-used to seal the door. So don’t remove all of it, you’ll want to use it again. Carefully peel away the plastic membrane closest to the speaker. Goal here is to open it up just enough so you can remove the speaker.

Identify Speakers Positive Terminal

Most bass blockers attach inline with the speakers positive terminal. Refer to the owners manual of the bass blocker you buy to be certain.

Once you have the speaker free, look at the back, and you should find 2 connectors, one red and one black. The red one is the one you want so you can insert the bass blocker.

You may also see a + and – symbol’s next to the terminals. The + is the same as red, that’s the one you want.

If you don’t see any of these, refer to the Owners book or repair manual and they should be able to help you identify which one is the positive terminal.

Techguys also has a great article that can help you further with identifying + and – on a speaker.

How To Install Bass Blockers

Now that the speakers are accessible and the positive terminal has been identified, you’re now ready to install the bass blocker.

From the positive terminal, measure roughly 3″ to 6″ and cut the positive wire using your wire cutters.

Use your wire stripping tool to remove 3/8 inches of plastic wire insulation from both ends of the positive speaker wire.

Find a matching set of male and female spade connectors. Insert them onto each end of the wires you just stripped. Use your wire crimper and crimp both ends.

If your bass blocker already has spade connectors, attach them now to the new spade connectors. Check with the installation manual for your bass blockers to see if they care about polarity (directional), most of the time it doesn’t.

Now it’s time to securely mount the bass blocker to the speaker so it doesn’t move around and cause unwanted buzzing or bumping noises. You can use electrical tape or any sturdy tape and fasten the bass blocker to the back side of the speaker.

Screw back in your speaker to the door, replace the plastic membrane, and re-install the door card.

Lastly, remember to reconnect your car battery.

Recommended Bass Blockers

Image	Product	Features	Price
Tweeters	PAC BB-6PR Bass Blocker for Tweeters	Reduce bass frequency below 5600 Hz	Check Price
3.5″ and 4″ Speakers	AUDIOPIPE BASS BLOCKERS	Reduces Bass Frequency below 2.8 kHz	Check Price
5.25″ Speakers	PAC Bass Blocker	Reduces bass frequency below 800 Hz	Check Price
6″ and 6.5″ Speakers	PAC BB-2PR Pair of Bass Blocker	Reduce bass frequency below 600 Hz	Check Price
6×9 Speakers	Audiopipe Bass Blockers	Reduces bass frequency below 300 Hz	Check Price

Frequently Asked Questions

What Bass Blocker should I buy?

Bass blockers come in different sizes, determined by the impedance and frequency cut-off points.
In general, the smaller the speaker, the less their ability to play lower frequency sounds.
Audiophiles will find the speaker specifications, find the impedance and frequency range of the speaker, and do the math to come up with the ideal frequency cut-off point for that speaker.
But for most car speakers, that kind of data is usually impossible to find.
Lacking this kind of data, finding a good bass blocker for the speakers installed in your car, may take some experimentation.
Here’s a list of the common sizes you can use as a guide, assuming 4 ohm speakers:
Up to 3.5″ Speaker: Bass blocker 0 – 2.8kHz
5.25″ Speaker: Bass blocker 0 – 800Hz
6.5″ Speaker: Bass blocker 0 – 600Hz
6×9 Speaker: Bass blocker 0 – 300Hz

What are Bass Blockers?

A Bass Blocker is a DIY’ers form of a speaker crossover, also known as a passive crossover. It’s simply a capacitor wired in-series with a speakers positive terminal. You’ll find this kind of arrangement on a good set of coaxial speakers where they put a bass blocker for the tweeter.
A bass blocker is a way for the handyman, without being super technical, to protect their speakers from damaging bass notes very economically.
When it comes to speakers, a capacitor’s functions is to filter out low frequencies. A bass blocker is a pre-packaged kit that makes it super simple to add a capacitor to block the bass on a speaker.

Conclusion

Bass Blockers do a great job at protecting speakers, especially if you like to turn up that volume! They’re simple to install with basic hand tools and all 4 speakers in a car can be done in an afternoon.

While you can DIY by figuring out what size capacitor to buy and install, most of us will like the convenience of a Bass Blocker kit. They’re just simpler, easier, and brain dead simple.