Hi,
I am seeking a response from the experts here.
In the quest to build DIY sub, I have been exploring 18 inch drivers which fits my requirements - which has greater xmax (i.e. above 12 min) to allow deep low end below 20hz in my 450 sq feet hall.
When I explained my plan about DIY sub to local dealers of faital pro, I was told not to build enclosure below the resonance frequency of the driver (Fs) as technically the driver wont be able produce signal below Fs. Although I explained the winisd simulation suggests it can produce signals below 20hz at higher SPL, he is not convinced about my decision. Also he strongly suggests to match it with min 1000w power rather than 500w which I believe would be more than enough for home usage.
Is there a problem in tuning enclosure below Fs for these drivers?
Does it really needs 1000w amp as I was told I would clip the amp with 500w?
I also read in data-bass about the performance of one of the top model (18HP1060) subwoofer is not that great and not suitable for below 30hz. While this review is for a top model, I doubt my decision now to tune lower for lower models drivers.
Considering the usage (home cinema) should I look at other brands instead?
Please advice - attaching the drivers winisd file in txt format.
I am seeking a response from the experts here.
In the quest to build DIY sub, I have been exploring 18 inch drivers which fits my requirements - which has greater xmax (i.e. above 12 min) to allow deep low end below 20hz in my 450 sq feet hall.
When I explained my plan about DIY sub to local dealers of faital pro, I was told not to build enclosure below the resonance frequency of the driver (Fs) as technically the driver wont be able produce signal below Fs. Although I explained the winisd simulation suggests it can produce signals below 20hz at higher SPL, he is not convinced about my decision. Also he strongly suggests to match it with min 1000w power rather than 500w which I believe would be more than enough for home usage.
Is there a problem in tuning enclosure below Fs for these drivers?
Does it really needs 1000w amp as I was told I would clip the amp with 500w?
I also read in data-bass about the performance of one of the top model (18HP1060) subwoofer is not that great and not suitable for below 30hz. While this review is for a top model, I doubt my decision now to tune lower for lower models drivers.
Considering the usage (home cinema) should I look at other brands instead?
Please advice - attaching the drivers winisd file in txt format.
Some thoughts:
- Drivers absolutely can produce signals below Fs, but going there suggests a different driver may be more suitable.
- 500w vs 1000w is a 3dB difference in peak output. If you can get 1000w within your budget, do that. If not, don't worry about it too much.
- I had a quick look around, and didn't see much mention of the 18HP1060 on DataBass.
- Even the top-end 18" PA drivers are usually optimised for high output from 30Hz and upwards. They're optimised more towards thermal power handling and sensitivity, with less excursion than their home theatre counterparts. Which drivers are best for you will depend on your application and expectations.
- The 18XL1800 driver might be a better fit for you. More Xmax, and a higher Qts means it can be persuaded to go below Fs in a ported box. In a ~400L box, it's >90dB@1w from 20Hz upwards, and will reach Xmax at 760w input, producing 119dB.
Chris
- Drivers absolutely can produce signals below Fs, but going there suggests a different driver may be more suitable.
- 500w vs 1000w is a 3dB difference in peak output. If you can get 1000w within your budget, do that. If not, don't worry about it too much.
- I had a quick look around, and didn't see much mention of the 18HP1060 on DataBass.
- Even the top-end 18" PA drivers are usually optimised for high output from 30Hz and upwards. They're optimised more towards thermal power handling and sensitivity, with less excursion than their home theatre counterparts. Which drivers are best for you will depend on your application and expectations.
- The 18XL1800 driver might be a better fit for you. More Xmax, and a higher Qts means it can be persuaded to go below Fs in a ported box. In a ~400L box, it's >90dB@1w from 20Hz upwards, and will reach Xmax at 760w input, producing 119dB.
Chris
PS - Found the 18HP1060 on DataBass. Having spent time with the 15HP1060, I agree with their assessment. Those drivers don't like being driven much past Xmax.
You're better of with drivers that are ment to go that low like the Dayton Ultimax series like the UM18-22, in a 300L sealed cabinet it can get to 20Hz with a max volume of 109dB at 20Hz. Those are known for that application and do it right with ease.
P.A. drivers are like said ment to stay higher and are build for robustness altough some (like Faital) do sound very good. But they were not ment to go that low so you need to trick them with dsp eq and so to do it right.
P.A. drivers are like said ment to stay higher and are build for robustness altough some (like Faital) do sound very good. But they were not ment to go that low so you need to trick them with dsp eq and so to do it right.
Thanks Waxx for your inputs.
Unfortunately, that Dayton driver is way too expensive here.
The idea to use PA drivers in HT environment came up after seeing some GSG Marty subs built by many bass enthusiasts and they all had claimed to have achieved with the results.
Drivers like B&C, LaVoce, Eminence were effectively used in the design that allowed to achieve lower tuning and higher spl in big enclsoures. The key here among these drivers was the higher Xmax to support high spl below 25hz.
In terms of EQ - I am sure guys would have put in High Pass filter around the tuning frequency to protect the driver but it does not need equalization is my understanding. Perhaps, this is more relevant to drivers with smaller displacement. Please share your inputs if I am wrong here
Thanks
P
Unfortunately, that Dayton driver is way too expensive here.
The idea to use PA drivers in HT environment came up after seeing some GSG Marty subs built by many bass enthusiasts and they all had claimed to have achieved with the results.
Drivers like B&C, LaVoce, Eminence were effectively used in the design that allowed to achieve lower tuning and higher spl in big enclsoures. The key here among these drivers was the higher Xmax to support high spl below 25hz.
In terms of EQ - I am sure guys would have put in High Pass filter around the tuning frequency to protect the driver but it does not need equalization is my understanding. Perhaps, this is more relevant to drivers with smaller displacement. Please share your inputs if I am wrong here
Thanks
P
You could consider the Dayton Ultimax in 15" as a slight compromise. I've sim'ed those against the 18" and they're darn close.
I think you're totally wrong, larger P.A. drivers can work lower, but need (dsp) eq and a lot of xmax and power to go lower than FS. And they loose a part of their sensitivty through that. But it can be done, that is true. It's just not the most efficient way of doing it. Actually, there is a way with horns and TL alignments, but those are rather complex to design and build, and often are very large and in case of horns also not the most neutral bass. TL is better on that but harder to do right. And even then you can't push them 20Hz lower than FS, only 5 to 10Hz lower.
And any driver that goes that low and loud will be expensive. Cheaper without eq could be the SB Acoustics SB34NRX75-6 or Dayton Audio RSS315HF-4, but i don't know if they go loud enough for you and it's not that much cheaper (at least not here). You need a driver with a low FS (<25hz preferable), high BL and xmax and enough sensitivity and power to go as loud as you want it, and those are expensive in general.
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Well, that's where things mislead a bit when the SPL simulation in winisd shows the driver can do without applying any EQ (108db @ 20hz @ 500w input after applying HPF)
Perhaps, the reality defies that theory?
I wouldn't expect to listen at reference levels and hence I am inclined to think now to tune a bit lower to 22 or 25hz on a driver with 30hz Fs. I would like to take advantage of bigger drivers to feel that punch and experience, thats all
Perhaps, the reality defies that theory?
I wouldn't expect to listen at reference levels and hence I am inclined to think now to tune a bit lower to 22 or 25hz on a driver with 30hz Fs. I would like to take advantage of bigger drivers to feel that punch and experience, thats all
If you tune it lower, the response won't be even without eq'ing the speaker. You can filter that out but will loose 4dB efficiency with the 18HP1030 and will have to put the HPF at 90Hz to keep a flat response without eq and will run out of xmax at 200w. With eq you can put hte hpf a bit higher. If you insist on it try it, but it's not what i would cal optimal.