[Justang99]

I am thinking of getting a pair of 6.5” mid bass woofers for 80Hz to 350Hz range. I can set my head units HPF to 80Hz, but the LPF will not go past 125Hz. So I’m wondering what to use to block the 350Hz+ going my 6.5s. I don’t want to buy a DSP. Is there a “treble blocker” similar to bass blockers?
Also, any recommendations for Mid Bass Woofers? I’m partial to Scan-Speak as I will be getting their silver series for my mid range and tweets, but I’m open to suggestions.

 

[miniSQ]

You want something similar to this. You can make one yourself by finding the correct cap and coil values for 350hz at the impedance of your drivers.

Amazon.com

 

[ItsonlyaHONDA]

Or you can use an in line crossover but I don't see one for 350. I see a 200 and a 500. They are 12db slopes, but if you double up to get 24db.

https://www.parts-express.com/brand/Harrison-Labs

 

[Justang99]

Or you can use an in line crossover but I don't see one for 350. I see a 200 and a 500. They are 12db slopes, but if you double up to get 24db.

https://www.parts-express.com/brand/Harrison-Labs

Thanks for that. I have a Sony AX7000, so I’m gonna run the 6.5s off of the Subwoofer Direct feature of the head unit. Puts out ~90W RMS. So I would need to splice the crossover into the speaker wire. And having said that, the channel will be pushing through 2 ohms… most of these crossovers are 4 ohm or 8 ohm. Is there any way to run it at 2 ohm?

 

[ItsonlyaHONDA]

Thanks for that. I have a Sony AX7000, so I’m gonna run the 6.5s off of the Subwoofer Direct feature of the head unit. Puts out ~90W RMS. So I would need to splice the crossover into the speaker wire. And having said that, the channel will be pushing through 2 ohms… most of these crossovers are 4 ohm or 8 ohm. Is there any way to run it at 2 ohm?

Honestly that beyond me.. I couldn't answer that. But you could hit up Harrison labs. They could probly answer that

 

[miniSQ]

Thanks for that. I have a Sony AX7000, so I’m gonna run the 6.5s off of the Subwoofer Direct feature of the head unit. Puts out ~90W RMS. So I would need to splice the crossover into the speaker wire. And having said that, the channel will be pushing through 2 ohms… most of these crossovers are 4 ohm or 8 ohm. Is there any way to run it at 2 ohm?

Is it possible this subwoofer direct channel is not full range? And is in fact limited in freq to the 125hz LPF?

 

[TheTodd]

And having said that, the channel will be pushing through 2 ohms… most of these crossovers are 4 ohm or 8 ohm. Is there any way to run it at 2 ohm?

They will work no matter the impedance. Depending on the impedance the crossover value will either increase or decrease. If I remember right, if the impedance halves from 4 to 2 ohms the LP will drop by one octave. So if your LP is 500Hz @4ohms, it will drop to 250Hz @2. Someone can correct me if I’m wrong…

 

[mdnky]

To build the crossovers you'll need to purchase the following components (assuming 4ohm, ~350Hz, 4th order LR):

• 2 x [L1] 3.3mH 18 AWG Air Core Inductor
• 2 x [L2] 1.75mH 18 AWG Air Core Inductor
• 2 x [C1] 150uF 100V Electrolytic Non-Polarized Crossover Capacitor
• 2 x [C2] 33uF 100V Electrolytic Non-Polarized Crossover Capacitor

You'll also need something to build them on (non conductive...like MDF, hardboard, acrylic,abs, etc.) You could grab perf board from PE as well. You'll should encase them in something that will prevent any shorts from occurring as well. Plastic project boxes could work, or shrink wrap. I usually prefer the 1st option.

 

[Justang99]

To build the crossovers you'll need to purchase the following components (assuming 4ohm, ~350Hz, 4th order LR):

• 2 x [L1] 3.3mH 18 AWG Air Core Inductor
• 2 x [L2] 1.75mH 18 AWG Air Core Inductor
• 2 x [C1] 150uF 100V Electrolytic Non-Polarized Crossover Capacitor
• 2 x [C2] 33uF 100V Electrolytic Non-Polarized Crossover Capacitor

You'll also need something to build them on (non conductive...like MDF, hardboard, acrylic,abs, etc.) You could grab perf board from PE as well. You'll should encase them in something that will prevent any shorts from occurring as well. Plastic project boxes could work, or shrink wrap. I usually prefer the 1st option.

View attachment 363547

Wow, that’s great, thanks! The only thing is, I want to run them off a single channel in parallel at 2 ohms… which components would I need for 2 ohm?

Thanks again

 

[mdnky]

For 2ohm:

• 2 x [L1] 1.75mH 18 AWG Air Core Inductor
• 2 x [L2] 0.80mH 18 AWG Perfect Layer Inductor
• 2 x [C1] 330uF 100V Electrolytic Non-Polarized Crossover Capacitor
• 2 x [C2] 80uF 100V Electrolytic Non-Polarized Crossover Capacitor

 

[Justang99]

For 2ohm:

• 2 x [L1] 1.75mH 18 AWG Air Core Inductor
• 2 x [L2] 0.80mH 18 AWG Perfect Layer Inductor
• 2 x [C1] 330uF 100V Electrolytic Non-Polarized Crossover Capacitor
• 2 x [C2] 80uF 100V Electrolytic Non-Polarized Crossover Capacitor

View attachment 363550

That’s great, thank you! Can I ask which component specification passes frequencies specifically below 350Hz?

 

[BMW 1M]

That’s great, thank you! Can I ask which component specification passes frequencies specifically below 350Hz?

All of them - it's a resonant circuit.

 

[mdnky]

Those are just the woofer side of a passive 2-way XO. A full 2-way (4ohm tweeter, 2ohm woofer) would look something like this:

This might help visualize what the differences are between the various levels. Based on data for a Dayton RS225 driver, with the values for the components rounded to the nearest readily available part value (hence the minor fluctuations in the response graph).

 

[LBaudio]

You can run only Hi-Pass filter from your head unit, LP-Filter can be set on your amplifier.....so you dont need to worry about pasive LPF

 

[Muu]

You can buy bare crossover PCB on eBay then populate the board with your chosen components to set the filter points. Only thing to be careful of is impedance matching if you're driving multiple drivers from a single amp.

 

[Justang99]

Is it possible this subwoofer direct channel is not full range? And is in fact limited in freq to the 125hz LPF?

Good point, I’ll have to check. The HU still gives the option to turn off the LPF with the sub direct channel on. Hence the need for an outboard crossover… I think.

 

[Justang99]

You can run only Hi-Pass filter from your head unit, LP-Filter can be set on your amplifier.....so you dont need to worry about pasive LPF

I’m running a Sony AX7000. 100Wx4 with LPF and HPFs from 60Hz to 125Hz. It puts out ~50+ watts per channel. The subwoofer direct bridge is about ~90W. So I was going to run 2-way components off of the front left and right channels and 2 6.5” woofers off of one sub direct channel. So no external amp for those speakers. I have a JL Slash 500/1 running a 10W3 in the back.