enough DSP flexibility might bring that cavity peak from the little horn down pretty well. I don't have the experience off hand to design a hit box from a HT spec high mass woofer. I would not want that 150Hz-ish peak and that's one reason probably to employ an absorber stub in some little Karlson designs. An R-J type vs Karlson might make more sense as there's very little cavity involved vs Karlson's approach. A tapped pipe could be good but assume too tall.
I don’t think the lab 15 was designed for HT I was under the impression it’s a pro sound sub (like a hybrid)? Not sure though!
Anyhow I was trying to bring the ‘chest thump’ with enough bottom to satisfy musically without adding more subs into the equation (waf!)
I suppose in reality it’s not that big of a deal for me to slap some test dummy boxes together....I’d be out a days time and 2 sheets of plywood to try the c15.
The impedence peaks although high are even....good?
The first excursion peak (which is still below x max)is right at 40hz which says maybe a good slam factor?
The Xmax is exceeded at 20hz but setting a hp at 20hz or so should fix that
A 80hz 12db lp should bring the hump into compliance where it can be met with the receivers hp wherever it blends best (probably around 150hz)
Phase and group delay looks decent?
Is there something I’m not seeing with the c15/lab15 ?
Other than it’d be easier to do it just about any other way! LoL
Edit.....well Freddi I reckon the only thing left to do is to just do it!
You tried like heck to talk me out of it so I certainly can’t blame you if my results are less than stellar!
Bob
Anyhow I was trying to bring the ‘chest thump’ with enough bottom to satisfy musically without adding more subs into the equation (waf!)
I suppose in reality it’s not that big of a deal for me to slap some test dummy boxes together....I’d be out a days time and 2 sheets of plywood to try the c15.
The impedence peaks although high are even....good?
The first excursion peak (which is still below x max)is right at 40hz which says maybe a good slam factor?
The Xmax is exceeded at 20hz but setting a hp at 20hz or so should fix that
A 80hz 12db lp should bring the hump into compliance where it can be met with the receivers hp wherever it blends best (probably around 150hz)
Phase and group delay looks decent?
Is there something I’m not seeing with the c15/lab15 ?
Other than it’d be easier to do it just about any other way! LoL
Edit.....well Freddi I reckon the only thing left to do is to just do it!
You tried like heck to talk me out of it so I certainly can’t blame you if my results are less than stellar!
Bob
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oh - have fun - it would not hurt to make your C15's vent adjustable - removable until you find the best spot in tuning.
I thought its specs looked "a bit" like some HT15 - say a Dayton RSS390HO
Thiele-Small Parameters
Resonant Frequency (Fs)21.5 Hz
DC Resistance (Re)3.2 ohms
Voice Coil Inductance (Le)1.79 mH
Mechanical Q (Qms)3.69
Electromagnetic Q (Qes)0.35
Total Q (Qts)0.32
Compliance Equivalent Volume (Vas)5.93 ft.³ (~167.94 liter)
Mechanical Compliance of Suspension (Cms)0.17 mm/N
BL Product (BL)19.8 Tm
Diaphragm Mass Inc. Airload (Mms)319g
Maximum Linear Excursion (Xmax)12 mm
here's your sealed box with something like a "Variovent"
I thought its specs looked "a bit" like some HT15 - say a Dayton RSS390HO
Thiele-Small Parameters
Resonant Frequency (Fs)21.5 Hz
DC Resistance (Re)3.2 ohms
Voice Coil Inductance (Le)1.79 mH
Mechanical Q (Qms)3.69
Electromagnetic Q (Qes)0.35
Total Q (Qts)0.32
Compliance Equivalent Volume (Vas)5.93 ft.³ (~167.94 liter)
Mechanical Compliance of Suspension (Cms)0.17 mm/N
BL Product (BL)19.8 Tm
Diaphragm Mass Inc. Airload (Mms)319g
Maximum Linear Excursion (Xmax)12 mm
here's your sealed box with something like a "Variovent"
Yes I was thinking about making an aperiodic type filter over the port for experimentation.
It’ll also work sealed.
Could even make a plate full of holes for when a port isnt a port!
Hopefully it’ll sound good one way or another.
I’ll keep ya posted.....it’ll be a couple wks b4 I can get to it.
Feel free to keep the ideas flowing!
Thanks, bob
It’ll also work sealed.
Could even make a plate full of holes for when a port isnt a port!
Hopefully it’ll sound good one way or another.
I’ll keep ya posted.....it’ll be a couple wks b4 I can get to it.
Feel free to keep the ideas flowing!
Thanks, bob
you're most welcome Bob. Here's what my crude model says for the sealed condition. There's a chance it could get more complex with the long vent's exit being blocked with that tunnel turning into a resonator.
Yes, had considered that and did wonder if it might be a benefit or detriment.....I suppose you answered that!
My solution is to make the port ‘shelf’ into dado grooves so it can slide in and out for tuning....with all the way out as an option.
Once figured out it could be glued in place.
Bob
My solution is to make the port ‘shelf’ into dado grooves so it can slide in and out for tuning....with all the way out as an option.
Once figured out it could be glued in place.
Bob
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