Hello all.
After some time of listening my semi finished 3 way active speakers it s time to finish them. But before i put paint on them i would like to squeeze as much as possible from them.
And here i hope that you, with much more expirience will give me some guide to do that.
The speakes are MTWW with two BMS 12s330 in 3.35 cubic feet closed cabinet. On top there is 18sound xt1086 horn with B&C DE250 driver and Focal 8v5411 on OB.
First im thinking to put midbass in closed box as there is not the best integration between woofers or to buy another one.
Then i will simulate vented box for woofers (same volume).
What i like on this speakes is dinamic and option to play loud effortless, but i miss some on top and better integration.
Regards.
After some time of listening my semi finished 3 way active speakers it s time to finish them. But before i put paint on them i would like to squeeze as much as possible from them.
And here i hope that you, with much more expirience will give me some guide to do that.
The speakes are MTWW with two BMS 12s330 in 3.35 cubic feet closed cabinet. On top there is 18sound xt1086 horn with B&C DE250 driver and Focal 8v5411 on OB.
First im thinking to put midbass in closed box as there is not the best integration between woofers or to buy another one.
Then i will simulate vented box for woofers (same volume).
What i like on this speakes is dinamic and option to play loud effortless, but i miss some on top and better integration.
Regards.
The DE250 isn't bad but if you miss something on top, a smaller diaphragm tweeter will very likely perform better.
The BMS 12S330 seems ill suited for sealed cabs as it has a Qts of 0.24.
I'd expect a very poor low bass performance similar to old Tannoy drivers which work best in large ported cabs tuned low ie along the lines of volume = Vas tuned to Fs.
No idea what 3.35 cubic ft is in liters.
I'd expect a very poor low bass performance similar to old Tannoy drivers which work best in large ported cabs tuned low ie along the lines of volume = Vas tuned to Fs.
No idea what 3.35 cubic ft is in liters.
The problem with adding drivers is that then i need another amplifier.
The woofer cabinet have about 95 liters. Yes the bass is a little shy and because of that i was thinking to add vent. Until now i was using Eq on my Najda DSP to add the bottom.
The woofer cabinet have about 95 liters. Yes the bass is a little shy and because of that i was thinking to add vent. Until now i was using Eq on my Najda DSP to add the bottom.
BMS suggest 44L ported, tuned to 31Hz for a -3dB point at 35Hz.
Since I've had my eye on that driver for a while I've simmed them and that appears to be very realistic.
As you use 2 per side you could put a partition into your 95L cab and it should be pretty much there once you deduct port tube and volume taken up by the driver.
In a sealed box and pretty much regardless of size they will start to roll off at around 175Hz so it is no wonder that they are bit bass shy.
As a bonus you'll gain a lot in max SPL or headroom depending on how loud you like it 🙂
Since I've had my eye on that driver for a while I've simmed them and that appears to be very realistic.
As you use 2 per side you could put a partition into your 95L cab and it should be pretty much there once you deduct port tube and volume taken up by the driver.
In a sealed box and pretty much regardless of size they will start to roll off at around 175Hz so it is no wonder that they are bit bass shy.
As a bonus you'll gain a lot in max SPL or headroom depending on how loud you like it 🙂
In-room performance differs drastically from what the simulations would suggest.
For instance, I'm listening to a pair of Seas H1252-08 in ~30L sealed boxes. In-room -3dB is about 10Hz, and there are peaks at 40Hz and 70Hz.
WinISD, Hornresp, etc suggest a -3dB point around 50Hz.
Aiming for an anechoic flat response is only useful for outdoor applications. In typical domestic spaces, I find the only sensible approach is to design for adequate power handling at low frequencies (a pair of sealed 8"s does fine for me), and EQ the result.
Chris
When tuned as I and BMS suggest you get an extended bass shelf response ie below 175Hz or so the response drops quickly by 3-6dB and the remains flat to tuning frequency below which it drops by 24dN/oct as usual.
In a sealed cab they just drop at around the usual 12dB/oct from around 175Hz, again as normal for sealed boxes.
EBS is my preferred response because with room gain there is a jolly good chance that it is flat enough in real life but room gain is nowhere near enough to help a low Qts driver in a sealed box IME.
I dislike boost EQ of any kind because it limits headroom and in my opinion headroom is a very underrated aspect of any loudspeaker system.
In a sealed cab they just drop at around the usual 12dB/oct from around 175Hz, again as normal for sealed boxes.
EBS is my preferred response because with room gain there is a jolly good chance that it is flat enough in real life but room gain is nowhere near enough to help a low Qts driver in a sealed box IME.
I dislike boost EQ of any kind because it limits headroom and in my opinion headroom is a very underrated aspect of any loudspeaker system.
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Uhm, no. With a that low Qt of 0,4 the drop will be less steep, my simulation shows ~7dB/oct.
I find dynamic one of the most important aspects in speakers. However, with 600W rating, a 3" coil, 8mm linear excursion and two drivers per side there's still plenty of headroom. You have to use a lowcut (on a reflex box anyway) and have to have enough power though. It's the same cone area as a 18" after all.
I try to simulate vented vs. closed box in WinISD but the program gives mi some kind of error so i dont know if the simulations are correct.
Vented box is tuned to 31 hz.
I measured box again with internal braces and it is actual 85 liters.
After tuning the woofer box i would like to try new mid-woofer. I was looking for Faital 10PR300. It have relative low mms and flat response. Any good alternatives?
And yes, i like it loud. 🙂
Vented box is tuned to 31 hz.
I measured box again with internal braces and it is actual 85 liters.
After tuning the woofer box i would like to try new mid-woofer. I was looking for Faital 10PR300. It have relative low mms and flat response. Any good alternatives?
And yes, i like it loud. 🙂
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On my backlog is a box that has some similarities to yours. It will use the Nd version of your woofers and the same horn. Mid will be 18s 10nmb420 and the horn driver will be a Faital HF10AK.
Planned is reflex tuning and the use of a WTMW topology due to the intended use of a crossover with reduced group-delay distortion. This crossover doesn't have lobing properties as nice as Linkwitz, therefore the topology with slightly more symmetry.
regards
Charles
Planned is reflex tuning and the use of a WTMW topology due to the intended use of a crossover with reduced group-delay distortion. This crossover doesn't have lobing properties as nice as Linkwitz, therefore the topology with slightly more symmetry.
regards
Charles
I will try to add slot port on the bottom of the enclosure tuned to 31hz.
Are there any disadvantages of slot ports versus round one?
Charles, what volume and tuning will you use for your woofers?
I was looking for 18 sound midwoofers too, but they are quite expensive. Since there are good reviews for faital 15pr400 i will try his little brother 10pr300. But there are not so many informations of users about this driver.
Are there any disadvantages of slot ports versus round one?
Charles, what volume and tuning will you use for your woofers?
I was looking for 18 sound midwoofers too, but they are quite expensive. Since there are good reviews for faital 15pr400 i will try his little brother 10pr300. But there are not so many informations of users about this driver.
The EBS alignment shows nicely there in your sim.
What I like about is that most of the time in room the drop doesn't really matter and if it really does matter it can almost perfectly remedied with just the old fashioned 100Hz bass control that almost every (pre-)amp used to have.
Not quite sure if you run both in a shared 85L cab or each in there own but a few liters either way shouldn't make too much difference although I'm more concerned by the volume taken up by ports rather than any partition.
See what you get for the woofers in 40L ported.
If possible I would split the cab internally into 2, one for each driver with its own vent.
Depends on where they are on your baffle...
Depends on where they are on your baffle...
It is planned to use 45 l per driver with a tuning frequency of 30 Hz. A little bit of a challenge with these drivers is the fact that they need to be tuned quite low in relatively small cabinets, leading to very long ports. I will use ports that are smaller in area than the simulators suggest in order to keep their lenght reasonable. But I boldly claim that the music I listen to doesn't send only content in the 30 Hz area to the woofers. So I think I will be on the safe side. And I will place the vents on the backside of the cab.
And be aware that the neo and the ferrite version differ slightly in their TSPs.
Regards
Charles
Long ports will have length-resonances and losses, especally if you fold it. You can easily avoid that by using passive radiators.
Passive radiators are horrible things.
The only viable excuse for using them is when the port volume exceeds box volume in tiny desktop speakers.
The only viable excuse for using them is when the port volume exceeds box volume in tiny desktop speakers.
No, it's not possible. I think that the only way is to add slot port at the bottom of the enclosure.
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