8 ohm tweeter with 4 ohm speaker

[2023 LTZ]

Oh, I’m uncertain of the difference between passive and active. The amp and hu both have co’s. They’re set at 60hz front and rear.
Fronts supposedly go to 55hz but not splitting hairs.

 

[Jimi77]

They are wired parallel. No cross overs to these as rears. The 4 ch is 2 ohm stable and I could not make a definitive conclusion after reading the article enclosed previously.
I cut power to the original amp, ran 12ga through the vehicle to the 4 corners of the sound stage. Focal something components which are 6.5” and 1”. I blew the focal tweets and replaced them w hertz 1”.
Rears are also focals in a 6x9 configuration but added back in the Bose 3.5” in parallel.
Rf t400x4 which can deliver 85wx4 at 4ohm. This is close to the speakers recommended input, same w the fronts. 75-80 front 90-100 or so to rears.

Before adding the 3.5s I could turn volume all the way up w no distortion. 5v preouts on the jvc kwv960.
Sounds amazing, just curious after reading the first post of this thread.

Bose tends to use low impendance drivers (1-2 ohms). Without knowing the impedance of the Bose speakers there is no way to know your final load.

 

[2023 LTZ]

Ill dmm the take outs and crawl in the trunk to see if I can get at those 3.5s too.

 

[2023 LTZ]

The Bose 6.5s and 6x9s are 2ohm. I’ll have to assume the 3.5s and tweets are as well as I cannot mm them w out removing the rear deck and pulling the speakers. Plus I can’t find the tweets in my garage.

 

[Jimi77]

The Bose 6.5s and 6x9s are 2ohm. I’ll have to assume the 3.5s and tweets are as well as I cannot mm them w out removing the rear deck and pulling the speakers. Plus I can’t find the tweets in my garage.

2 ohms sounds right. So you're running at ~1.333ohms (2ohm + 4 ohm parallel). Hopefully it's a solid (Korean) amp that can handle that type of abuse.

 

[2023 LTZ]

Is 1.33 the load presented by all 4 speakers on the back deck?

 

[Jimi77]

Is 1.33 the load presented by all 4 speakers on the back deck?

1.33 ohms is the final load of a 2 ohm + 4 ohm speaker run in parallel. I assume you have one 6x9 (4ohms) + one 3.5" Bose (2 ohms) hooked up to each of the rear channels. If that is correct, then you have a 1.33ohm load on each of your rear channels.

 

[2023 LTZ]

Much appreciated for that clarity.
I’ll look to series them to raise it as I believe I have room provided by the amplifier.

 

[2023 LTZ]

Your assessment is exactly right.
If I seriesed that combination I’d be a bit above 4ohm? If that’s the case I’m going to do that and feel fortunate I haven’t damaged anything..

 

[Jimi77]

Wired in series, you'll be at 6 ohms and reduce output considerably (going from 1.33 ohm to 6 ohm will reduce output ~6-7db). Running the Bose in series with the (superior) Focal driver actually reduces power to the Focal speaker. I think you'd be better off ditching the Bose driver or putting a ~50 watt 2 ohm resistor in series with the Bose driver, which would bring your final load up to 2 ohms and attenuate the Bose driver which I imagine is considerably louder in your set up. The Bose driver probably has a good 2-3db sensitivity advantage and it's getting twice the power as the Focal (+3db). What you perceived as sounding better when adding the Bose driver into the system is really just more DBs.

 

[2023 LTZ]

Yeah that’s all making sense now.
Thanks Jimi
Imma pul that Bose out.
That’ll leave an escape hatch for the sub pressure to escape through.
Grassy ass amigo.

 

[Jimi77]

Yeah that’s all making sense now.
Thanks Jimi
Imma pul that Bose out.
That’ll leave an escape hatch for the sub pressure to escape through.
Grassy ass amigo.

Good luck. Keep in mind if the 6x9s are free air, then you're going to cancellation. You may want to block that 3.5" hole.

 

[2023 LTZ]

Will that outweigh the potential benefit of venting those 2 12s that swallow 800w each at 2 ohm? Or maybe I should be concerned of blowing the bottom out of the 6x9s?

I do have the 6x9 regular rings too if what you’re saying is an issue. I have no idea if those 6x9s are free air..

 

[Jimi77]

Will that outweigh the potential benefit of venting those 2 12s that swallow 800w each at 2 ohm? Or maybe I should be concerned of blowing the bottom out of the 6x9s?

I do have the 6x9 regular rings too if what you’re saying is an issue. I have no idea if those 6x9s are free air..

Free air means the 6x9s are not in an enclosure.

 

[2023 LTZ]

Back deck, over trunk. Certainly not air tight.

I know it’s a dramatic difference in chest compression when the back seat is open to the trunk.


I appreciate you clarifying all this for me.
Hopefully it’s useful to the one who started the thread.