Speaker Impedance Curves: Why Are These Ones So Different?

Stratoblaster

Fractal Fanatic
I've been wondering for a while now why some speaker impedance curves are so....'non-standard'.

Examples are the Hipower and Rumble 4x12 SIC's; why are their SIC's 'wavy' and don't have a singular hump in the low end as most do? Interactions of the drivers/cabinet? Does the amp output topology/circuitry react to those cabs in a unique way? I'd be interested to hear why this is the case.
 

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Help me understand something with impendance curves. I use my fm3 both with IRs to FOH ( i use a 2x12 engl ir) and with a real cab for stage volume ( an orange ppc212). What impedance curve would you choose? I guess the best way would be to use the same IR and cab if possible but that is very difficult playing live. You just never know the backline.
 
Help me understand something with impendance curves. I use my fm3 both with IRs to FOH ( i use a 2x12 engl ir) and with a real cab for stage volume ( an orange ppc212). What impedance curve would you choose? I guess the best way would be to use the same IR and cab if possible but that is very difficult playing live. You just never know the backline.
I always prioritize the front of house sound as that's what the audience is hearing. Stage volume is just so I can hear myself. If the tone isn't quite right it isn't a big deal.

So whatever curve sounds best for the sound you want to give the sound guy to project to the audience is what I would use.
 
I always prioritize the front of house sound as that's what the audience is hearing. Stage volume is just so I can hear myself. If the tone isn't quite right it isn't a big deal.

So whatever curve sounds best for the sound you want to give the sound guy to project to the audience is what I would use.
Yes this makes total sense. I could swap a curve one for rehearsals with a real cab and one for live shows.
I also wonder if the loadbox curves that seem flat is a better workaround. To my ears they don't but in live senarios things change a lot.
 
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What are you using for a power amp into your cab? If it's a tube power amp into the cab then disabling the power amp modelling entirely is best because that amp and cab will have their own genuine impedance interaction. If you're using (most, but I think not all) solid state power amps, then leaving it on and choosing a curve close to your real cab would be most authentic (but not necessarily best sounding).

But your front of house sound and IR might work best with a different SIC, so at that point it's just whatever compromise works best.

Remember at the end of the day that regardless of that the "proper" way is, ultimately whatever sounds best for the music you're making is the correct choice. Both sound to the audience, and what feels best to you and inspires you to play.

Since you have two amp blocks, you could potentially have a whole amp (and therefore separate SIC) for your FOH and monitoring setup if that makes the most sense.
 
What are you using for a power amp into your cab? If it's a tube power amp into the cab then disabling the power amp modelling entirely is best because that amp and cab will have their own genuine impedance interaction. If you're using (most, but I think not all) solid state power amps, then leaving it on and choosing a curve close to your real cab would be most authentic (but not necessarily best sounding).

But your front of house sound and IR might work best with a different SIC, so at that point it's just whatever compromise works best.

Remember at the end of the day that regardless of that the "proper" way is, ultimately whatever sounds best for the music you're making is the correct choice. Both sound to the audience, and what feels best to you and inspires you to play.

Since you have two amp blocks, you could potentially have a whole amp (and therefore separate SIC) for your FOH and monitoring setup if that makes the most sense.
You usually can't hear FOH well enough to adjust its tone well. Don't see how a separate amp for it makes sense.

Make yourself happy in the context of your band playing its music, let FOH handle FOH.
 
+1
Sometimes I'm told afterwards the guitar was a bit low in FOH mix while on stage the guitar cuts through "kickass".
… which is prolly why it was low in the FOH mix — the volume coming off the stage was plenty. 😂

(I once mixed for a guitarist with double Marshall stacks on-stage — who was mad as a hornet that his guitar was so low on the “board cassette” from that nights’ show…)
 
+1
Sometimes I'm told afterwards the guitar was a bit low in FOH mix while on stage the guitar cuts through "kickass".
… which is prolly why it was low in the FOH mix — the volume coming off the stage was plenty. 😂

(I once mixed for a guitarist with double Marshall stacks on-stage — who was mad as a hornet that his guitar was so low on the “board cassette” from that nights’ show…)
I've had that happen too. I coordinate with the FOH to find that happy balance between me being able to hear myself and not filling the room from my backline.

I probably make it a bit harder for FOH, or maybe myself, because I treat my amps like they have a single channel so I use the guitar's volume to go from clean to crunch to lead, and as a result my gain and volume in the room rises equally.

The guy who runs FOH most of the time says he likes that I do it, it makes it easier for him, because my solos are loud enough to be heard but then I drop back into the mix when I'm done. I just do it because it's old school, and I don't have to bother with stepping on a switch hoping that it's the right amount of gain/volume, using the knob I know when to stop turning it.

I do have clean, crunch and lead scenes on the modeler if someone else is sitting in on it, but crunch and lead are where I live.
 
That's interesting... would porting change some feedback mechanism in a speaker impedance because the speaker isn't fighting the 'air spring'?
Yes.

A loudspeaker is really a transformer. But instead of transforming one electrical impedance to another, it transforms an electrical impedance into a mechanical impedance. And vice-versa. Porting changes the mechanical impedance of the cab, and that gets transformed into a change in the cab's electrical impedance.
 
I've had that happen too. I coordinate with the FOH to find that happy balance between me being able to hear myself and not filling the room from my backline.

I probably make it a bit harder for FOH, or maybe myself, because I treat my amps like they have a single channel so I use the guitar's volume to go from clean to crunch to lead, and as a result my gain and volume in the room rises equally.

The guy who runs FOH most of the time says he likes that I do it, it makes it easier for him, because my solos are loud enough to be heard but then I drop back into the mix when I'm done. I just do it because it's old school, and I don't have to bother with stepping on a switch hoping that it's the right amount of gain/volume, using the knob I know when to stop turning it.

I do have clean, crunch and lead scenes on the modeler if someone else is sitting in on it, but crunch and lead are where I live.
Sounds like a perfect player/FOH gig to me — you do your thing and I’ll grab it if it gets out of hand.
 
Sounds like a perfect player/FOH gig to me — you do your thing and I’ll grab it if it gets out of hand.
Last week he and I were talking about it and I was really touched by his comments. I just do what seems right and to hear it was what worked for him was like … “COOL!”
 
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