Will exchanging horn for tweeter change cabinets resistance?

[LowHz]

This has always been a curiosity, but now I'm actually faced with this: I recently bought an SWR Working Pro 1x15 (8 ohm). I pulled the Eminence-made speaker and dropped in an 8 ohm cast-frame SWR 15", and now am considering going a step further and replacing the tweeter (which has an attenuator on the back of the cab) with an SWR horn/tweeter, listed at "8 ohms." I'm curious if this will affect the cabs resistance (logic would tell me I'd end up with a 4 ohm load, but ...).

I guess I've always been baffled as to how the resistance of a tweeter or horn doesn't seem to be a part of the cabinet's "stated" resistance (e.g., two 8-ohm speakers and a horn of whatever ohmage still being labeled a 4-ohm cab).

Can anyone help? Thanks in advance!

[Ben Clarke]

Resistance is a simple measurement performed with DC (no audio frequency). You're thinking of impedance, which varies with frequency.

When seperated by a crossover, a HF driver and LF driver will not affect the impedance of the other driver, except where they are producing the same frequency (near the crossover point where their operations overlap). The crossover effectively increases the impedance of the horn driver outside of it's operating range to the point where no power will transfer from the amp to the horn driver at those frequencies, and will have no appreciable impact on the impedance of the cone driver. The amplifier still "sees" the cone driver in the box as if the horn weren't even there.

[billfitzmaurice]

Originally Posted by LowHz

I guess I've always been baffled as to how the resistance of a tweeter or horn doesn't seem to be a part of the cabinet's "stated" resistance (e.g., two 8-ohm speakers and a horn of whatever ohmage still being labeled a 4-ohm cab).
!

Passive Crossover Slopes
BTW, drivers aren't rated for resistance nor 'ohmage'; they have impedance, which is measured in ohms.

[dincz]

Originally Posted by billfitzmaurice

Passive Crossover Slopes
BTW, drivers aren't rated for resistance nor 'ohmage'; they have impedance, which is measured in ohms.

and inchage doesn't affect hertzage

[MuzikMan]

Originally Posted by billfitzmaurice

Passive Crossover Slopes
BTW, drivers aren't rated for resistance nor 'ohmage'; they have impedance, which is measured in ohms.

I don't know, so many people are using "ohmage" these days it just might have a chance of making it into the dictionary . I remember when "aint" wasn't a word !!

[Ben Clarke]

Originally Posted by MuzikMan

I don't know, so many people are using "ohmage" these days it just might have a chance of making it into the dictionary . I remember when "aint" wasn't a word !!

I used to cringe every time I heard a colleague use "ohmage" on dealer support calls...

[billfitzmaurice]

Originally Posted by MuzikMan

I don't know, so many people are using "ohmage" these days it just might have a chance of making it into the dictionary .

It is, as a colloquialism. It won't be found in a technical document, for the same reason inchage and hertzage aren't.

[MuzikMan]

Originally Posted by billfitzmaurice

It is, as a colloquialism. It won't be found in a technical document, for the same reason inchage and hertzage aren't.

I know, Ima justa teezin'

[BassmanPaul]

Originally Posted by LowHz

I pulled the Eminence-made speaker and dropped in an 8 ohm cast-frame SWR 15"

As a matter of interest what was this supposed to accomplish apart from a crapshoot???

[silky smoove]

Originally Posted by MuzikMan

I don't know, so many people are using "ohmage" these days it just might have a chance of making it into the dictionary . I remember when "aint" wasn't a word !!

Ohmage is already in the dictionary. Makes my skin crawl.

[BassmanPaul]

Originally Posted by silky smoove

Ohmage is already in the dictionary. Makes my skin crawl.

Must be an American dictionary!

[silky smoove]

Originally Posted by BassmanPaul

Must be an American dictionary!

True... Those jerks over at Merriam-Webster are ruining it for everybody!

[LowHz]

Hey, that was quick! Thanks everyone for your responses -- especially Ben, who put me on the correct path. The rest of you criminals provided true entertainment and rectified my limited electronics vernacular (thanks to you all, as well). I've always tended to use impedance, resistance, ohmage (go ahead, cringe now), ohms, etc., interchangeably. Going forward I may just use "omegas" as my new "you know what I mean" catch-all term. What do you think? "The cab is eight omegas." Yeah, that works!

Paul -- To answer your question in regard to what I hoped to accomplish by pulling the original Eminence-made "custom-specified, model-specific SWR bass driver" and replacing it with the SWR cast-frame speaker: (1) the latter (I believe this one was PAS-made) handles 350 watts as opposed to 200 (and there may be rare times when I use this thing solo -- jazz or acoustic stuff); (2) I like the sound of the cast-frame SWR better -- although I haven't ever seen the specs on this speaker, it does seem to reproduce lower fundamentals better (despite SWR listing this speaker in the "Son of Bertha" cab [same dimensions as the Working Pro 1x15 that we're dealing with here] as sitting at 45Hz, while the 200W stamped-frame in this Working Pro cab is listed at 40Hz). My guess is that the specs on the cast-frame driver might be skewed toward the lower end of the spectrum(?). All I know is that it sounds better; and (3) the cast-frame speaker has that cool "SWR" logo on the dust cover -- which obviously makes it sound better even when it's not plugged in. Sort of like how your car runs better after it's been washed ...

Again, thanks to all who responded.

[MuzikMan]

Fuggedaboudit!

[Ben Clarke]

yes, the omegas of the gophers and weasels do not interact when rockin the proppa krunkover.

[LowHz]

And I guess therein lies the rub, Ben -- I don't know if the krunkover that's currently in the Working Pro 115 and delineating signal for a LeSon weasel at God-knows-what imepdance will work for a Foster horn listed at 8 ohms.

[Blues Bass 2]

This Eminence high pass will work with the foster horn , I've used them before . You just need to wire it in place of the single cap .
Eminence PXB:3K5 High Pass Crossover Board 3,500 Hz

[BassmanPaul]

Originally Posted by LowHz

Paul -- To answer your question in regard to what I hoped to accomplish by pulling the original Eminence-made "custom-specified, model-specific SWR bass driver" and replacing it with the SWR cast-frame speaker: (1) the latter (I believe this one was PAS-made) handles 350 watts as opposed to 200 (and there may be rare times when I use this thing solo -- jazz or acoustic stuff); (2) I like the sound of the cast-frame SWR better -- although I haven't ever seen the specs on this speaker, it does seem to reproduce lower fundamentals better (despite SWR listing this speaker in the "Son of Bertha" cab [same dimensions as the Working Pro 1x15 that we're dealing with here] as sitting at 45Hz, while the 200W stamped-frame in this Working Pro cab is listed at 40Hz). My guess is that the specs on the cast-frame driver might be skewed toward the lower end of the spectrum(?). All I know is that it sounds better; and (3) the cast-frame speaker has that cool "SWR" logo on the dust cover -- which obviously makes it sound better even when it's not plugged in. Sort of like how your car runs better after it's been washed ...

Again, thanks to all who responded.

Problem with this approach is that it's all "speaker in a box" kinda thinking. A driver and it's enclosure have to work in harmony with each other. Just putting driver X into cabinet Y without doing the science is a crapshoot at best, thus my comment, and a damaged driver at worst. Read through the FAQs for more on this.