Does a speaker on a switch change the crossover point of a component set?

[Bwap]

I have been considering wiring a 8ohm supertweeter on a switch in paralell, so when I open the doors I can drop the ohms and raise the output while adding the distance effect of the supertweeter. Say im wiring a component set that is 4 ohms and crossed at 5k. When I switch the supertweeter on, the impedance the amp sees would drop to 2.66 ohms. The amp I have can supply sufficient power at either load.

Would the crossover point of the component set change because of the change of impedance on the line?

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[keep_hope_alive Premium Member]

depends. the crossover point will change if you add/remove load on the load side of a passive crossover.

so don't do that. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

the DPST switch should engage the supertweeter and it's dedicated crossover - and connect ahead of any other passive crossovers.

 

[Bwap]

depends. the crossover point will change if you add/remove load on the load side of a passive crossover.
so don't do that. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

the DPST switch should engage the supertweeter and it's dedicated crossover - and connect ahead of any other passive crossovers.

Hmm I was hoping I could just run separate power for the tweeter and add the switch on the power and wire it in parallel.

If that's not possible, is there another switch that I could use that isn't made for a thermostat?.. I was hoping I could use SPST Heavy Toggle switch but if not, its not a big deal.

As long as the load doesn't change the xover point when wired in before the xover, wouldn't this work?

 

[maylar 10+ year member]

Yes that would work. You might want to consider an 8 ohm stereo L-Pad before the switch so you can set the supertweet's level.

 

[Bwap]

Yes that would work. You might want to consider an 8 ohm stereo L-Pad before the switch so you can set the supertweet's level.

Thanks, good to know. I have been considering a new setup as I found I can fit an 8 inch midrange in the front.

I hear that 8 inch midranges can get muddy 3-5k.. so id like to wire together an 8", a 3" and a silk dome on each door.

The problem I have is how would I get 200 rms to the 8" and such low power to the 3"(most 3" have low power handling)

I have the amp to push the power, I just don't know how to split up the power so I don't blow through 3"s regularly.

 

[maylar 10+ year member]

You might want to post about an extended range 8 and skip the 3".

 

[Bwap]

Yea I don't like the idea of the 3"

 

[keep_hope_alive Premium Member]

a dpst switch is needed. you need to disconnect both positive and negative or it will mess with the other crossover components.

 

[Bwap]

a dpst switch is needed. you need to disconnect both positive and negative or it will mess with the other crossover components.

Thanks, didn't think of that.. I have updated my diagram like so...

I have a few new questions now..

As far the Lpad, I would need one mono Lpad per supertweeter correct?

And as far as crossover components, should I go with air core inductors and metalized poly caps for best SQ?

(I have heard that these are the best, wondering if there are reasons why I should go with other materials and where)

What should I mount the caps and coils onto?(fiberglass?)

 

[keep_hope_alive Premium Member]

looks good. yes, one mono Lpad per tweeter. i like that idea as well.

air core is fine. poly caps are fine.

buy a blank project board from RadioShack

Grid-Style PC Board with 750 Holes : PC Boards | RadioShack.com

 

[keep_hope_alive Premium Member]

looks good. yes, one mono Lpad per tweeter. i like that idea as well.

air core is fine. poly caps are fine.

buy a blank project board from RadioShack

Grid-Style PC Board with 750 Holes : PC Boards | RadioShack.com

 

[Bwap]

looks good. yes, one mono Lpad per tweeter. i like that idea as well.
air core is fine. poly caps are fine.

buy a blank project board from RadioShack

Grid-Style PC Board with 750 Holes : PC Boards | RadioShack.com

Thanks, you have been a huge help to me. My reason for joining this forum was because I needed to pm you and gain some of your knowledge, now I find myself on here several times a day. haha //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Ill be ordering those parts today. Any reason you say the type of cap and coil I chose are "fine"? If there is something else I should use for a certain part, then please let me know.

 

[keep_hope_alive Premium Member]

fine is just a simple answer. they are good and inexpensive.

 

[Bwap]

Obviously this is the final wiring diagram, just making sure everything checks out.

Also I have been on a huge debate on whether to get Newegg.com - Powerbass 4XL-80-94 8" Midrange Car Speaker or PWX 8" mid range - Crescendo Audio | Online Store.. Any advice on which of those to choose would be appreciated. I will be crossing them about 3-4k.