I'm very new to inductors - was just playing w/#'s. 4 cabs without it models pretty flat, however. I provided the HR inputs so you folks could look at all the screens without me flooding my post w/pics. I can sure post them all next time if preferred. As far as delay and transient issues are concerned, I still consider myself new at this and am not entirely sure what to look for. Feel free to point out the problems with that driver in the SS15 enclosure. It looks good from a far, but may be far from good..? Maybe I have my beer goggles on.
In addition, this idea was based on the idea that many have already built SS15's, so the extra wood thing was negated.
In addition, this idea was based on the idea that many have already built SS15's, so the extra wood thing was negated.
No prob Crescendo, many other factors are all part of the system and have each their own influence. As you can see they don't show up in the SPL response. As far inductors, for high power LF cabs they are not a great idea, I think. To much loss and their influence will show up in real measurements under these power conditions.
The quickest method for searching suitable replacements in TH's you can select them first on similar BL force and mass. You will see if you find similar parameters that in most cases they will work and give similar response. However, even if all parameters are alike they will still have their own characteristic sound (something nobody seems to discuss around here).
The quickest method for searching suitable replacements in TH's you can select them first on similar BL force and mass. You will see if you find similar parameters that in most cases they will work and give similar response. However, even if all parameters are alike they will still have their own characteristic sound (something nobody seems to discuss around here).
Right, this I understand
Ok, got it. I saw another member suggest it to flatten response, but maybe that's only through a certain power level. And another member also recommended against it for pretty much the same reason you mentioned.
Thanks for the starting point. I like in BassBox 6 how you can load drivers to a database and search for drivers within certain specs. It'd be so nice if there were a way for us to help each other build a database to make finding drivers that much easier/quicker...AND if Hornresp used the driver search function
Yup! I can't count how many people I've expressed this to.
As far as the Phase Response and Group Delay charts go, am I looking for a smoother line where I want response?
Anybody tried to generate a single sheet TH for this?
MCM Audio Select 12'' Die Cast Professional Woofer - 350W RMS | 55-2982 (552982) | MCM Audio Select
MCM Audio Select 12'' Die Cast Professional Woofer - 350W RMS | 55-2982 (552982) | MCM Audio Select
Jbell did, it's called the SS15 (just a bigger smile in response but it could work if the data is correct and you don't mind some group delay of 23ms at system resonance)
Last edited:
Hey DJIM:
you get no arguments from me on LF extension and it being part of modern music. I guess what I was trying to say, was that with the SS15 and the music I was listening to -- I couldn't tell any difference in LF extension between the 2 different high pass setups I was trying. I think the reason for that was 2 fold -- 1, the SS15 just has a certain amount of 40hz or possibly lower it'll actually reproduce, and 2, the music I typically listen to isn't extremely bass heavy in the 28-32hz area.
I do think the 32hz butterworth 24db/oct high pass should allow for the maximum (safe) LF content from a SS15 from the discussion earlier -- I just couldn't verify that by ear with my music.
It is much easier to look at the cone movement with pink noise and determine that at whatever level you consider "full tilt boogie" the cone does not exceed Xmax by much.
With the 3015LF, as long as the peak to peak movement is around 3/4 inch or less, the speaker is in the safe zone as far as excursion.
Okay, sorry Jim for the wrong Dutch interpretation my side. The last filter (12dB/oct + EQ’s) settings I gave should give you the lowest possible response. The idea behind the 12dB/oct is to use the lowest slope that is similar to the natural roll-off of the cab. The downside is that it starts cutting from 100Hz so you need one broadband para eq to compensate that. The second small band EQ (at 40Hz) is an attempt to compensate about 50% at 40Hz. All settings are based on your Smaart Graph that shows roll-off from 60Hz.
Last edited:
hi justin
we discussed the inducter isue in the other topic.
jason pointed out to me that as we introduce an inductor ,we also introduce resistance,wich in turn re-introduce peaks .
so your probably better of not using them at all.
also mh vallues are often given @ 1kz.
as frequenty decreases ,induction increases.in fact it usually doubles or more @ 30>100 hz hz
i discused this with david mcbean.
in pa we can safely take the le vallue @1khz and double it for use in a sub model
Who is we? Cause I haven't seen any 'doubling' method in any PA sub I came across. Of course I haven't seen them all but I would like to know.
But I think what you meant is that a driver with an inductor in serie raises its impedance as frequency increases. Also a sub with relative low frequency Fs can influence the crossover. You can correct this by a LCR network. But in this case of just an inductor in serie with the driver you don't need to correct this. The added resistance of a high power inductor is relative small (< 0,4Ohm) cause otherwise it would act more as a heater instead of passing the power. But still the inductor can heat up significant under stress conditions (power loss) and that's why inductors are no longer favoured in times of active filtering/powering.
There are a few things you need to consider with inductors for high power PA subs;
1.) What is the saturation point of the inductor (saturation results in distortion)
2.) Power loss.
3.) That a high magnetic field of the loudspeaker can influence the inductor
4.) It can change the impuls/excursion behaviour significant.
The last one is very important for high power loads. All LF PA drivers have an optimized cone damping to smooth out the response at high power loads (often optimised at max continues power). When an inductor is used in series the cone damping/impulse behaviour is influenced and often results in higher excursion. Although this increases SPL also it is VERY important to measure this. At high power it can make the difference between killing a LF driver or not! One of the positive side effects is the pleasing 'punchy/impulsive' sound. Often this is the main reason why inductors are used in high power subs.
Last edited:
here is an example of a mh curve of a beyma (i think 18")driver.
few manufactures show this info.
they usually only show 1kh and 10 khz values
as you can see below 100 hz induction is ~ double the 1 khz value.
here is an other post with ts of a selelenium with le @ 10 khz ,1 khz and fs
i discused it with david mcbean here in the hornresponce topic
but maybe i am incorrect.
few manufactures show this info.
they usually only show 1kh and 10 khz values
as you can see below 100 hz induction is ~ double the 1 khz value.
here is an other post with ts of a selelenium with le @ 10 khz ,1 khz and fs
i discused it with david mcbean here in the hornresponce topic
but maybe i am incorrect.
Last edited:
No, you are not incorrect but you are talking about voice coils and not external inductors that was suggested. Voice coils have relative high resistance, are moving in a magnet field and are coupled to a changing physical resistance (cone). External inductors are not moving in a magnetic field, have the lowest resistance possible and therefore should have stable variables. If they didn't we couldn't use them in crossovers, would we
?!
Last edited:
in the 1st part of the reponce i was talking about a series coil.
1.8 mm 3 mh coil has a resistance of 0.4 ohm
if you add 0.4 to the rg in hr,you reintoduce peaks(wich you want remove)
even 0.2 ohm wil do that.
that was discussed in another topic.
but i think we can agree that a coil in pa use should be avoided,or kept to a minimum for varius reasons.
2nd part of the responce to justin was the voice coil inductance and how one could double the 1 khz vallue for the sub region.
1.8 mm 3 mh coil has a resistance of 0.4 ohm
if you add 0.4 to the rg in hr,you reintoduce peaks(wich you want remove)
even 0.2 ohm wil do that.
that was discussed in another topic.
but i think we can agree that a coil in pa use should be avoided,or kept to a minimum for varius reasons.
2nd part of the responce to justin was the voice coil inductance and how one could double the 1 khz vallue for the sub region.
Show me please cause I'm a little sceptic that it can have that kind of impact within the bandpass of TH subs.
Yes and no, I totally agree with avoiding such afterwards correction as much as possible. On the other hand it wouldn't be the first time a 6th order bandpass or TH (similar behaviour) could benefit from an inductor.
Actually, that statement is even arguable cause those graphs you refer too don't show the non-linearities of the inductance of a voice coil under different power loadings (think of temp and resistance rise, changing magnetic field by excursion2nd part of the responce to justin was the voice coil inductance and how one could double the 1 khz vallue for the sub region.
)
Last edited:
Well the 3015LF is back in stock.
And I really must say I feel for you guys, @~1000 posts of collaborative refinement and you get the rug yanked out from under the value proposition.
And I really must say I feel for you guys, @~1000 posts of collaborative refinement and you get the rug yanked out from under the value proposition.