And then the speaker is brought to a room and the room modes make the frequency response a roller coaster, 10dB peak there and 10dB dip there. No sign of the knee and slope anywhere where the box simulator predicted. Setup in a different room and the response is again totally different. 🙂
While it is nice to have low bass from the stereo main speakers they won't be enough no matter the alignment because of the room. Add few subs and the situation gets better. And now you see the last inch of low extension wasn't even necessary.
Always remember to mind the top end of the woofer bandwidth more than the low end, so that it works acoustically well. if the lows happen as well then nice! Otherwise, just add a sub or more.
Gotta remember subs are not necessary an option because decoration and extra wires and cost and so on, but the room modes still stay and sweating on box alignment is almost time wasted. Better use the effort to make sure there is no resonances and mids leaking the port on the bass box for example. All kinds of evil to mid range performance can happen when focus is on the low frequencies for no good reason. Have fun! 🙂
While it is nice to have low bass from the stereo main speakers they won't be enough no matter the alignment because of the room. Add few subs and the situation gets better. And now you see the last inch of low extension wasn't even necessary.
Always remember to mind the top end of the woofer bandwidth more than the low end, so that it works acoustically well. if the lows happen as well then nice! Otherwise, just add a sub or more.
Gotta remember subs are not necessary an option because decoration and extra wires and cost and so on, but the room modes still stay and sweating on box alignment is almost time wasted. Better use the effort to make sure there is no resonances and mids leaking the port on the bass box for example. All kinds of evil to mid range performance can happen when focus is on the low frequencies for no good reason. Have fun! 🙂
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edit time over, an example. If the bass extension is wanted to go to 40Hz for example, lets say the -3db point at 40Hz. Now, if the room / listening spot combination has a null around 40Hz you are never going to reach the response target no matter what woofer, 10" on 30 litre cabinet or 18" on a 300 litre cabinet, sealed, reflex, bandbass or free air, what ever. Radical? Yes it is. And yes, there could be a peak there instead, in which case the target response could be reached with mucho smaller system.
Anyway, the point is the room dominates the response of bass, the cabinet you are building dominates the response above the bass. This is particularly important to realize on a two way speakers where the bandwidth of the woofer goes to the mids, wavelenghts smaller than the box, sometimes even smaller than the driver.
I might be overlooking something, so tweak the bass if there is need for it. But one should first and foremost make sure the mids are alright where the driver and box actually makes a difference.
Anyway, the point is the room dominates the response of bass, the cabinet you are building dominates the response above the bass. This is particularly important to realize on a two way speakers where the bandwidth of the woofer goes to the mids, wavelenghts smaller than the box, sometimes even smaller than the driver.
I might be overlooking something, so tweak the bass if there is need for it. But one should first and foremost make sure the mids are alright where the driver and box actually makes a difference.
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Another late evening thought: the bigger the woofer and box, the more there is room for problems in the mid range. For this reason there is absolutely no need for system bigger than preferred SPL level requires, because if there is a problem in the sound you dont want to turn it loud, you want to turn it down 🙂 philosophy to rescue, minimize the size of an enclosure and driver for least potential problems.
I don't know what good sized woofer system would be. Anything that makes the skin tingle and smile on the face. Box and woofer minimization is achieved naturally by adding more ways to the system. Small stuff for the mids, big for the bass.
I don't know what good sized woofer system would be. Anything that makes the skin tingle and smile on the face. Box and woofer minimization is achieved naturally by adding more ways to the system. Small stuff for the mids, big for the bass.
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This is kind of an ill-suited advice if the scope was set as full range, two channel, two-way setup, as was the case here. The merits of the multi sub approach are well documented, yet, some may still decide against. Also, it is not irrelevant how deep the woofer digs, this is a misunderstanding on your side. Modes will destroy the homogeneity of the bass, but the low extension ability in a ported enclosure is a feature of the woofer. Extension is something different than smoothness of frequency response, and it is particularly difficult with ten-inch woofers to find a good one for a reasonable sized enclosure.
addition:
addition:
This is wrong, you are taking f3 point literal, but it is one way to express the extension of a continuous spectrum. A null messes up a part of this spectrum, but does not erase all.
Not at all, a bass reflex enclosure is pretty much about augmenting bass response.
Now this is getting all philosophical ... 😛
And pretty much off track for the intended two-way system! 😉
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Yes it is, ill advice for the quest. Main motivation for the text was to highlight the midrange performance. This advice alone will make a system better if it triggers a thought process in the builder to mind the mids. The lows are ruled by the room so any bass can be built, just dont forget the mids 😉
Most of the time we build what we want and not what the system wants, to achieve what we are trying to achieve. Anyway, late night philosophy so take it as it is 🙂
You could read my example with any target frequency, the low slope wont matter because it is a rollercoaster anyway. there is difference if system plays to 30Hz or 80Hz of course, but 40 or 50 not so sure because either could play to 30Hz depending on the room. In the end a slope on a graph is not very important, only thing that matters is if the bass is satisfying or not. Let it play as low as possible without compromizing the mids is my suggestion.
Most of the time we build what we want and not what the system wants, to achieve what we are trying to achieve. Anyway, late night philosophy so take it as it is 🙂
You could read my example with any target frequency, the low slope wont matter because it is a rollercoaster anyway. there is difference if system plays to 30Hz or 80Hz of course, but 40 or 50 not so sure because either could play to 30Hz depending on the room. In the end a slope on a graph is not very important, only thing that matters is if the bass is satisfying or not. Let it play as low as possible without compromizing the mids is my suggestion.
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With the comparative graphs I followed Graham's wish to check first what can be achieved without any further electronic boosts. It was not so much about lowest possible f3, I in my case would use DSP assist anyway and look for no less than ~40 Hz. Still this was not the point. They first and foremost show that two woofers (Fane and Faital) ask for less volume and higher tuning, which in a bigger enclosure translates into the deficient bass response if a lower tuning is chosen for extension, a recessed lower bass. I might be wrong, but after listening for quite a while to speakers that showed such a recessed bass shelf first, I think I was able to discern this shelved bass, even if filled in by room gain, from one that has a flat response and needs to be further room EQ-ed to remove the excessive room mode gain peaks (but his is actually an open question that I have). Anyway, with woofers that show a recessed bass with a lower tuning, there is even more EQ needed if one targets a flat response, or settle with higher tuning from the start (not an option for me, again).
Apart from the question of resonances, which I cannot say anything about because I know no measurements, all of the woofers have Mms that is within the range of those paper cone pro woofers that are considered as good mid frequency performers. Although this remains dubious, after I read a discussion between Zvu and Earl and the later was not agreeing on a Mms limit.
Apart from the question of resonances, which I cannot say anything about because I know no measurements, all of the woofers have Mms that is within the range of those paper cone pro woofers that are considered as good mid frequency performers. Although this remains dubious, after I read a discussion between Zvu and Earl and the later was not agreeing on a Mms limit.
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Yes a room EQ could improve things on the listening position. And, satisfying bass could be anything from a 6.5" woofers and up, depends how loud the system is played.
I have 15" on the mains, very nice powerfull experience but problems on the sound with crossover around 200Hz and this is already third enclosure proto trying to make a 200Hz xo work better. Hence my concern. Next step is to sacrifice SPL capability with smaller yet enclosure to get problems higher up above the passband. Went for the bass, and now retrieving because the box sound ruins the mids.
I have 15" on the mains, very nice powerfull experience but problems on the sound with crossover around 200Hz and this is already third enclosure proto trying to make a 200Hz xo work better. Hence my concern. Next step is to sacrifice SPL capability with smaller yet enclosure to get problems higher up above the passband. Went for the bass, and now retrieving because the box sound ruins the mids.
Cheers! I had looked at this driver but it seems to be discontinued. Also, having spent a Saturday trying and eventually succeeding after losing my mind doing it I mah have decided to never ever ever try and flush mount and irregularly shaped driver again!
Attachments
It is supposedly available at 62.6 GBP on your side of the channel: https://www.soundlite.co.uk/Sovereign-Pro10-300SC/de
Routing it flush should not be too crazy, it is basically a circle and you need stop early of finishing the round, then cut four straight lines between the end points.
Routing it flush should not be too crazy, it is basically a circle and you need stop early of finishing the round, then cut four straight lines between the end points.
The plan for this winter (I got the parts just before covid...) is a 2226h + a 4594HE-16ohm with a hypex (123 or 253). woofer cab a custom designed cnc-milled shape and some large horn on top.
At the moment Im trying to build the 3d model of the woofer (im building it fully parametric Rhino/Grasshopper).
Horn: Apart from the classic horn calculators, (XO around 650hz??), I now going through the Ath4 posts...
All help, ideas and educational pointers more than welcome!
Depending on the horn/waveguide you use, you might want to raise the XO frequency a bit to have the directivity of the 2226 match the horn/waveguide. The 2226 can easily go up to almost 1kHz.
Saw some video on youtube that used 3D printed template to route against with a template router bit. You could 3D print filler flange to a round hole as well. Endless possibilities with additive manufacturing 🙂 My irregular routings have all contained some errors, really easy to make mistakes.
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Many ideas, but what is the context?
Home hifi use, PA use for small personal concerts, PA use professional usage etc etc ?
Just only these parts, or do you want to add subwoofers etc?
Thanks. Im still thinking of the horn. I was going for some tractrix but Im reading the Ath4 (OS-ES?) thread and Im trying to understand if its better for 600 to 800hz XOs
15 inch and WAF optimized? 😕 😛 😀 😀
In my experience, a multisub will also work much better in that regard.
It's a lot easier to camouflage 2 or 3 little subs
But in this case, this JBL is a good example of active EQ'ing a BR.
By default, one can only get a decent response in 65liter tuned @ 55Hz.
-3dB will be around 60Hz.
With JBL I forgot what they exactly use for xmax (I haven't used JBL in a very long time).
But according the datasheet, the standard;
(VCheight - Gap height) / 2 = (19.05 - 8.1)/2 = 5.5mm
The datasheet says 7.6mm, which probably is calculated "the PA way".
The Fs is around 40Hz, so normally we don't want to get much lower than this.
However in a BR, this can be stretched a little because of the excursion dip.
Since this thing has an insane sensitivity for home use purposes, I think there will be a little wiggle room.
So to actively correct this, we can use 65 liter again, but tune it at 42Hz.
Next we add a para EQ with Fs=40Hz, Q=1.2 G=6dB
The new response will be -3dB @ 42Hz
Even when played at 108dB (pure theoretical), the cone excursion is only around 1.5mm and goes up below 36Hz.
Looking at the power curve (VA), the max power at this point is a tiny 38W @ 40Hz. So all is good.
This will give a semi standard butterworth-isssh response.
Personally I wouldn't recommend using this woofer this way.
It falls a little bit in "no man's land".
40Hz -3dB is not really that low, one could stretch it maybe a tiny bit more, 35Hz or so.
But it becomes a bit much like pushing and pulling at that point.
Boosting 6dB is already quite a lot.
This woofer seems to be really optimized for your traditional PA setup.
Which is around 60-80Hz for the tops and the rest for the subs.
For home/hifi purposes I would recommend using this in a closed or even open-baffle or cardioid system. Down to 100Hz or so.
Or as closed subwoofers, down to 35Hz, but not much lower than that! (depending on SPL's)
Anyway, don't wanna steal this topic, so maybe you can open your own topic to discuss about the possibilities?
In my experience, a multisub will also work much better in that regard.
It's a lot easier to camouflage 2 or 3 little subs
But in this case, this JBL is a good example of active EQ'ing a BR.
By default, one can only get a decent response in 65liter tuned @ 55Hz.
-3dB will be around 60Hz.
With JBL I forgot what they exactly use for xmax (I haven't used JBL in a very long time).
But according the datasheet, the standard;
(VCheight - Gap height) / 2 = (19.05 - 8.1)/2 = 5.5mm
The datasheet says 7.6mm, which probably is calculated "the PA way".
The Fs is around 40Hz, so normally we don't want to get much lower than this.
However in a BR, this can be stretched a little because of the excursion dip.
Since this thing has an insane sensitivity for home use purposes, I think there will be a little wiggle room.
So to actively correct this, we can use 65 liter again, but tune it at 42Hz.
Next we add a para EQ with Fs=40Hz, Q=1.2 G=6dB
The new response will be -3dB @ 42Hz
Even when played at 108dB (pure theoretical), the cone excursion is only around 1.5mm and goes up below 36Hz.
Looking at the power curve (VA), the max power at this point is a tiny 38W @ 40Hz. So all is good.
This will give a semi standard butterworth-isssh response.
Personally I wouldn't recommend using this woofer this way.
It falls a little bit in "no man's land".
40Hz -3dB is not really that low, one could stretch it maybe a tiny bit more, 35Hz or so.
But it becomes a bit much like pushing and pulling at that point.
Boosting 6dB is already quite a lot.
This woofer seems to be really optimized for your traditional PA setup.
Which is around 60-80Hz for the tops and the rest for the subs.
For home/hifi purposes I would recommend using this in a closed or even open-baffle or cardioid system. Down to 100Hz or so.
Or as closed subwoofers, down to 35Hz, but not much lower than that! (depending on SPL's)
Anyway, don't wanna steal this topic, so maybe you can open your own topic to discuss about the possibilities?
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Cheers man!
It's not the how to, it's more the faff! 🙂
Workshop Co-ax Mini Bangers - B&C 5CXN44
It really is, isn't it.
Yeah, I got so frustrated this weekend I thought about buying a desktop CNC or 3D printer just to end my woes. I could buy a decent 3D printer tomorrow but I just don't have the space. Also, the frustation of a long print messing up half way through might put me in an early grave.