How do Bass Blockers work…

[s.abushaikha]

How does adding resistance to a circuit only cut off/lower a certain frequency output of a speaker?

If I add a “4 ohm” bass blocker to a “4 ohm” speaker, will the speaker now play half the volume since the circuit will now see “8 ohms?”

Can someone explain please before I purchase bass blockers for my dash speakers…

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[1aespinoza Premium Member]

How does adding resistance to a circuit only cut off/lower a certain frequency output of a speaker?

If I add a “4 ohm” bass blocker to a “4 ohm” speaker, will the speaker now play half the volume since the circuit will now see “8 ohms?”

Can someone explain please before I purchase bass blockers for my dash speakers…

It is not a resistance but rather a capacitor. If it is marked as 4 Ohms it is because the capacitance will block a certain frequency and up. Let us say the capacitor is marked 200 Hz @ 4 Ohms; if you use it on an 8 Ohms speaker, it will now work as 100 Hz @ 8 Ohms.

 

[s.abushaikha]

It is not a resistance but rather a capacitor. If it is marked as 4 Ohms it is because the capacitance will block a certain frequency and up. Let us say the capacitor is marked 200 Hz @ 4 Ohms; if you use it on an 8 Ohms speaker, it will now work as 100 Hz @ 8 Ohms.

Ahh ok, I understand, so it won’t really lower the overall volume of the speakers

 

[1aespinoza Premium Member]

Ahh ok, I understand, so it won’t really lower the overall volume of the speakers

Correct.
One more thing. If you have door speakers as well, make sure the overlap is not too much between them both. Otherwise you will have alot of shared frequencies and the sound stage will be pulled up and overbearing.

 

[s.abushaikha]

Correct.

So I still want to preserve as much mid-bass and mid range / vocals as possible while avoiding distortion, I don’t seem to have issues with distortion in the front dash, however when I use the fader and balance to isolate each corner speaker I feel it sounds a little gargle like on bass heavy songs. Sometimes they clip/pop on very heavy thumps or kicks while listening to certain rap artists.

I’m looking for 4ohm 100hz bass blockers, since I think vocals start around that point, but can’t find any.

 

[1aespinoza Premium Member]

I’m looking for 4ohm 100hz bass blockers, since I think vocals start around that point, but can’t find any.

Check this out.

 

[1aespinoza Premium Member]

I’m looking for 4ohm 100hz bass blockers, since I think vocals start around that point, but can’t find any.

What you will need is 400 micro Farad capacitors for 100Hz @ 4 Ohms.

 

[Mitchell Fosgate III]

How does adding resistance to a circuit only cut off/lower a certain frequency output of a speaker?

If I add a “4 ohm” bass blocker to a “4 ohm” speaker, will the speaker now play half the volume since the circuit will now see “8 ohms?”

Can someone explain please before I purchase bass blockers for my dash speakers…

Dash speakers? bass blocking crossovers are for if you want to add a subwoofer to the preamp outputs of the head units. Not using an amplifier then. It will act as a high pass filter. Blocking deep bass from entering the two front speakers. So louder sounds can enter the subwoofer.

 

[CertifiedHoodClassic]

How does adding resistance to a circuit only cut off/lower a certain frequency output of a speaker?

If I add a “4 ohm” bass blocker to a “4 ohm” speaker, will the speaker now play half the volume since the circuit will now see “8 ohms?”

Can someone explain please before I purchase bass blockers for my dash speakers…

"Bass blockers" are just capacitors, if you want to know how they work, you can look into resistor-capacitor circuits, or RC circuits. But you don't need to know the theory, just know that capacitors do things in an AC circuit (which sound is an AC signal), and the important bit is that they 'filter' (reduce magnitude) of low frequencies. In this RC circuit, your speaker is actually the resistor and the bass blocker is the capacitor. The cutoff point is based on both the resistance (your speaker ohms) and the capacitance (which bass blocker you buy).

In fact, you can make your own bass blocker by using a calculator, buying a capacitor with the right value, and wiring it series with your speaker. ie: https://www.omnicalculator.com/physics/rc-circuit

Now you go to ebay and look up 400uF caps.

 

[CertifiedHoodClassic]

And the TLDR is that speaker resistance does affect your filter frequency, and bass blockers work well but getting the caps you need cost less.

Although bass blockers don't cost much so I wouldn't blame you for buying them.

 

[Deiimos]

I would suggest sticking to non-polar capacitors (also called bipolar). Regular electrolytic caps don’t like the AC waveform out of an amp and can fail / not filter correctly; crossover caps are always NP / BP and are marked as such. I don’t know if this was mentioned or not, didn’t see it, but maybe I missed it. This mainly applies to electrolytic capacitors, which such high values bass blockers need to be, will almost certainly be electrolytic, and if DIY’ing them. If you buy actual bass blockers they will already be the right type.

 

[Old_Slapper]

Can we just delete Mitchell now?

 

[1aespinoza Premium Member]

Can we just delete Mitchell now?

Do not be too eager to deal out death in judgment. Even the very wise cannot see all ends. My heart tells me that Gollum has some part to play in it, for good or evil, before this is over.
-Gandalf

 

[s.abushaikha]

Im debating whether to just buy the bass blockers I want or what the one guy said about the caps on ebay. Or do I keep them full range speakers on the dash. I don't seem to have much issue with clipping or distortion, maybe slightly with some music...