Looks like a very capable woofer. Any reason not to stack more Nero 21's? they can fit with a 40 cm depth.After a lot of thinking I finally decided to renew and rearrange all the subwoofers in my room. My goal is having clean and meaningful 10-150Hz output to be ready for Dirac ART.
First action will be the renewal of the front subwoofer that reside behind my AV wall. I'm fairly happy with the four old Visaton TIW400 in their sealed enclosure but they're excursion limited and drop off quickly under 20Hz. Driver choice proved to be harder than I first thought. I wanted to keep the depth of that sub limited to 40cm and extend it from floor to ceiling (248cm) so staying with 15" woofers seemed logical. But as I live in the EU, affordable 15" subwoofers with decent specs are hard to find so I extended my search to 18" woofers. As I already have a very good experience with PA drivers I ordered 4x Faital Pro 18XL1800 with 20mm x-max earlier this week. They were delivered today and you can easily see that their build quality is top notch and they're capable of moving a lot of air.
Their enclosures will be ported this time. The volume will be 1200L (divided in 2 stacked boxes for practicality) and the tuning 12Hz so GD will only rise under 20Hz. As expected WinISD simulates an excursion limit under tuning @ 450W but with that power the sub will already output >110dB from 10Hz and up. Furthermore there is not a lot of bass under 10Hz in movies and the suspension will keeps things in check down low so I probably won't need a HPF for protection.
Second action is building a huge riser. We have put our back seat on a temporary riser for a few months and the whole family likes the concept. The exisiting 21" subwoofers will be built-in. Maybe the old 15" subs can be reclaimed too. I've read that Dirac ART allows you to choose the support frequency of each sub?
I've just spend 3 days using ART with my new Storm Audio SSP. It was a fun learning curve, and yes, you can certainly set a support frequency for each sub. I divided my current subs into 2 groups. Front subs and rear subs.
My front subs can't go very deep with enough output so they only support down to 35-45hz. Rear subs are more capable and support down to 20hz, but infrasonic turned off for now.
One very important thing I learned about ART is that you need to select one main LFE sub. In my instance that turned out to be the front right sub which is a REL 212/sx. It simply cannot handle the output requirements in my room and I have to limit the output in the bass below 40hz our it completely bottoms out and compresses like crazy.
So whatever you do, if you plan to incorperate ART, make sure to bunch up a few subs that are selected as 1 main LFE sub.
Once my 8 x 21" sealed subs are completed/built I am considering to make at least 4 or 8 of them run as 1 sub main LFE channel to make sure it has enough output.
All other subs are supporting the main LFE sub and you cannot set their target curve per say. They will support the main LFE sub's target curve to make it flat/whatever you decided.
I guess you are clueless because you didn't read the explanation in the links in post #59.
https://data-bass.ipbhost.com/topic...-content-thread-films-games-music-etc/?p=1459
Post #2 (Posted October 9, 2012) has the:
Measurement Methodology:
The Overall Star Rating is an average of the following four categories (each one explained in greater detail below):
1. Level
2. Extension
3. Dynamics
4. Execution
1. Level - This is measured by digitally bass-managing the 5.1 or 7.1 signal. The Level is a composite number, and is calculated by the average of the [1] highest peak in dB (maximum 126dB for 5.1, 128dB for 7.1), [2] the average/RMS dB level of the track (125ms integration time) and [3] the RMS peak level (loudest single 1/8th of a second of the film) in dB. Full modulation of the waveform is considered to be 0dBFS. The ratings are as follows:
5 Stars - >112.5dB composite
4 Stars - >110dB composite
3 Stars - >107.5dB composite
2 Stars - >105dB composite
1 Star - <105dB composite
2. Extension - The same bass-managed digital signal above is analyzed with Spectrum Lab, with Nuttall windowing, and either a 1 second or 2 second integration time (the longer the integration time, the higher the resolution, at the cost of dynamic peaks, but for the extension category, it is a moot point). Extension is determined as the -10dB point from the overall peak of EITHER the Peak (green) or Average (red) trace, whichever is higher. The ratings are as follows:
5 Stars - <10Hz extension
4 Stars - <15Hz extension
3 Stars - <20Hz extension
2 Stars - <25Hz extension
1 Star - >25Hz extension
3. Dynamics - The Overall RMS/Average Level of the track from the Level category is subtracted from the Overall Peak Level of the track from the Level category. The ratings are as follows:
5 Stars - >27.5dB Dynamics
4 Stars - >25dB Dynamics
3 Stars - >22.5dB Dynamics
2 Stars - >20dB Dynamics
1 Star - <20dB Dynamics
4. Execution - This is the only purely Subjective category, and will be decided by a plurality in a poll, with single star increments available to be voted on. Vote what you thought about the LF use in the track, and note any clipping/compression/filtering that took place
Please note that no objective measurement system is perfect. The way the measurement scheme is set up, it will be very difficult to achieve 5 Stars overall, and very few films have done so. How good a movie is to watch has no bearing on how it measures. This is a way to objectively look at the low frequency content of a track without all the subjective "it was awesome" and "seismic" rhetoric from professional reviewers for nearly every BD release.
There will be some films which are LF monsters that will not garner 5 Stars overall, and everyone has their favorites. In toto, you can expect a film with a higher Overall Star Rating to have more LF than one with a lower star rating, and most of the 4+ Star films/tracks are very good LF experiences.
At any rate, plenty of low end content is available if you want it.
https://data-bass.ipbhost.com/topic...-content-thread-films-games-music-etc/?p=1459
Post #2 (Posted October 9, 2012) has the:
Measurement Methodology:
The Overall Star Rating is an average of the following four categories (each one explained in greater detail below):
1. Level
2. Extension
3. Dynamics
4. Execution
1. Level - This is measured by digitally bass-managing the 5.1 or 7.1 signal. The Level is a composite number, and is calculated by the average of the [1] highest peak in dB (maximum 126dB for 5.1, 128dB for 7.1), [2] the average/RMS dB level of the track (125ms integration time) and [3] the RMS peak level (loudest single 1/8th of a second of the film) in dB. Full modulation of the waveform is considered to be 0dBFS. The ratings are as follows:
5 Stars - >112.5dB composite
4 Stars - >110dB composite
3 Stars - >107.5dB composite
2 Stars - >105dB composite
1 Star - <105dB composite
2. Extension - The same bass-managed digital signal above is analyzed with Spectrum Lab, with Nuttall windowing, and either a 1 second or 2 second integration time (the longer the integration time, the higher the resolution, at the cost of dynamic peaks, but for the extension category, it is a moot point). Extension is determined as the -10dB point from the overall peak of EITHER the Peak (green) or Average (red) trace, whichever is higher. The ratings are as follows:
5 Stars - <10Hz extension
4 Stars - <15Hz extension
3 Stars - <20Hz extension
2 Stars - <25Hz extension
1 Star - >25Hz extension
3. Dynamics - The Overall RMS/Average Level of the track from the Level category is subtracted from the Overall Peak Level of the track from the Level category. The ratings are as follows:
5 Stars - >27.5dB Dynamics
4 Stars - >25dB Dynamics
3 Stars - >22.5dB Dynamics
2 Stars - >20dB Dynamics
1 Star - <20dB Dynamics
4. Execution - This is the only purely Subjective category, and will be decided by a plurality in a poll, with single star increments available to be voted on. Vote what you thought about the LF use in the track, and note any clipping/compression/filtering that took place
Please note that no objective measurement system is perfect. The way the measurement scheme is set up, it will be very difficult to achieve 5 Stars overall, and very few films have done so. How good a movie is to watch has no bearing on how it measures. This is a way to objectively look at the low frequency content of a track without all the subjective "it was awesome" and "seismic" rhetoric from professional reviewers for nearly every BD release.
There will be some films which are LF monsters that will not garner 5 Stars overall, and everyone has their favorites. In toto, you can expect a film with a higher Overall Star Rating to have more LF than one with a lower star rating, and most of the 4+ Star films/tracks are very good LF experiences.
At any rate, plenty of low end content is available if you want it.
Thanks for your effort to explain the table. I gather it relates to standard level on the medium and may reveal something about dynamic range. Of course, not meaningful to assess dynamic range unless you measured soft conversation levels compared to peak levels.
Loudness at the seats is something else again, and related to the number your volume control is pointing to.
Might help some of the less sophisticated like me understand the table if you could "parse" one of two of the movies in full sentences.
Loudness at the seats is something else again, and related to the number your volume control is pointing to.
Might help some of the less sophisticated like me understand the table if you could "parse" one of two of the movies in full sentences.
Agreed but they're painfully expensive and for the 80" you need a separate concrete building as the subwoofer enclosure.And if you want 47 or 172 liters of displacement with one driver, Ascendo has a 163kg 50", 105 dB at 5 Hz, and a 260kg 80", around 114dB at 5Hz.
View attachment 1255642
Pricey drivers, but that's a "whole lotta shakin' goin on"
They're meant to fire into the left corner of my room like the old sub already does. I'd need a 60 cm deep enclosure to fit 21's and the 18's can do with 50-52 cm. Look at the attached rendering for clarification.
Wow amazing to read how such a beastly sub like the REL with four 12" woofers can't keep up. What 21" woofers did you choose?
Plan is to have 4x 18" ported LLT behind the wall, 6x 15" for LCR, 4x 21" ported LLT in a riser firing into the deep back corners. That way the front 4x 18" will become the main LFE sub. I'll also keep the support frequency in check. With DLBC I use a 20Hz curtain and I'll probably stay with that value.
I'll see what I can do with the old 4x 15"s. I can also build the into that riser (center back) They're still excursion limited (unless I put them in a Qtc = 0.85 enclosure) and they also can't take much power in a LLT.
2x drivers gets that pressure going.
Quick attacks or transients less likely
to have distortion. Even though 1x
drivers be fine, for the most part.
1x10 or 1x12 will get most Apartment
or Condo dwellers in trouble regardless.
Sound design was getting pretty good
for movie sound effects.
Now days, everything copies the same
4 or 5 bass type sound effects.
So whatever investment to hear same old
Puhhhh ewwwwwwwwwww
I just noticed the quick "bursts" that are
common for movies. Got my Sub in trouble.
Little distortion at the first attack. Otherwise
the sub is more than capable to rattle the
walls with pressure and get the cops to show.
But with 2x subs. Sharp attack transients
with Bass. Made the strange warble/ flutter
Go away. With listening levels still the same.
Just more pleasing while watching movies.
To have no strange occasional flutter
Quick attacks or transients less likely
to have distortion. Even though 1x
drivers be fine, for the most part.
1x10 or 1x12 will get most Apartment
or Condo dwellers in trouble regardless.
Sound design was getting pretty good
for movie sound effects.
Now days, everything copies the same
4 or 5 bass type sound effects.
So whatever investment to hear same old
Puhhhh ewwwwwwwwwww
I just noticed the quick "bursts" that are
common for movies. Got my Sub in trouble.
Little distortion at the first attack. Otherwise
the sub is more than capable to rattle the
walls with pressure and get the cops to show.
But with 2x subs. Sharp attack transients
with Bass. Made the strange warble/ flutter
Go away. With listening levels still the same.
Just more pleasing while watching movies.
To have no strange occasional flutter
Apologies, I'm responding late on this.
Compact folder dipoles (of which so-called Ripoles are a subset) are fascinating, but I don't believe they are a practical approach for infra-bass extension, because the driver volume displacement would need to be enormous. Siegfried Linkwitz, who did much to develop and promote compact folded dipoles, created a spreadsheet to calculate the maximum SPL available from a given dipole configuration. It's still available at Linkwitz Lab - see here: https://www.linkwitzlab.com/spl_max1.xls
I entered the numbers for the Ripoles built by @tubelectron (i.e. a pair of Beyma 12BR70 drivers, with a path length estimated at 450mm). At 15Hz, the excursion-limited maximum SPL will be around 67dB at 1m. That's not just quiet, it's below the threshold of audibility (which is above 70dB at 20 Hz, on the ISO 226:2003 contours). What might well be audible, though, is the harmonic distortion. For example if there's fourth harmonic around 3%, which there could easily be at maximum linear excursion, that equates to around 37dB at 60 Hz, which probably is audible.
Folded dipoles are well worth exploring, but the physics means they are best suited to the 'regular' bass range, say 30 Hz and up.
Last edited:
Thanks @ianbo,
Yes, in my little configuration (below), I do not need high SPL levels - that's why I used 12" speakers (12BR70 offers 8mm Xmax), which proves to be more than enough to handle infra-bass at sound levels that are already difficult to bear for long here...
That said, a friend of mine was amazed by the Ripole when he came home, and decided to build a pair of 2x18" Ripoles to match his horn multi-amplified system... What I can say is that he sold his two Velodyne subwoofers now.
See below, the Ripoles were not already finished yet. The speakers used inside are SB Audience Bianco 18SW450 - two per Ripole, like I did on my Omega Ripole :
The efficiency of his system is at least 100dB/w/m, and he listen VERY loud
"to retrieve the impression of the concert" : the two Ripoles, each driven by external 1kW sub amps, operates flawlessly, giving all the expected infra-bass. The active crossover FC is set at 40Hz.
Indeed, for high levels of loudness, you need large speakers with large Xmax and power capabilities, since the Ripole principle is not high efficiency dB/w/m. That's why I wrote that for Home Theater, it may not be the best solution !
Otherwise, for Audio, at "usual home volume" if I can say so, the Ripole is an excellent system for reaching deep, tight and uncolored infra-bass extension, moreover with the advantage of a compact-sized enclosure.
T
Yes, in my little configuration (below), I do not need high SPL levels - that's why I used 12" speakers (12BR70 offers 8mm Xmax), which proves to be more than enough to handle infra-bass at sound levels that are already difficult to bear for long here...
That said, a friend of mine was amazed by the Ripole when he came home, and decided to build a pair of 2x18" Ripoles to match his horn multi-amplified system... What I can say is that he sold his two Velodyne subwoofers now.
See below, the Ripoles were not already finished yet. The speakers used inside are SB Audience Bianco 18SW450 - two per Ripole, like I did on my Omega Ripole :
The efficiency of his system is at least 100dB/w/m, and he listen VERY loud
"to retrieve the impression of the concert" : the two Ripoles, each driven by external 1kW sub amps, operates flawlessly, giving all the expected infra-bass. The active crossover FC is set at 40Hz.Indeed, for high levels of loudness, you need large speakers with large Xmax and power capabilities, since the Ripole principle is not high efficiency dB/w/m. That's why I wrote that for Home Theater, it may not be the best solution !
Otherwise, for Audio, at "usual home volume" if I can say so, the Ripole is an excellent system for reaching deep, tight and uncolored infra-bass extension, moreover with the advantage of a compact-sized enclosure.
T
Last edited:
Ok now it makes complete sense. Very nice that an 18 can fit in thereThey're meant to fire into the left corner of my room like the old sub already does. I'd need a 60 cm deep enclosure to fit 21's and the 18's can do with 50-52 cm. Look at the attached rendering for clarification.
Wow amazing to read how such a beastly sub like the REL with four 12" woofers can't keep up. What 21" woofers did you choose?
Plan is to have 4x 18" ported LLT behind the wall, 6x 15" for LCR, 4x 21" ported LLT in a riser firing into the deep back corners. That way the front 4x 18" will become the main LFE sub. I'll also keep the support frequency in check. With DLBC I use a 20Hz curtain and I'll probably stay with that value.
I'll see what I can do with the old 4x 15"s. I can also build the into that riser (center back) They're still excursion limited (unless I put them in a Qtc = 0.85 enclosure) and they also can't take much power in a LLT.
Those 18's x 4 with LLT will be an extremely capable LFE main sub with ART!I ordered 8 x SBA Nero 21SW1100D's and 4 already arrived. Cabinets are done very shortly, unfortunately 4 of the woofers are in back order, so won't arrive until feb. I will install the 4 x 21's behind my AT screen and make them LFE main sub for ART (And another 4 when the woofers arrive).
I have 2 x 15" that I might put behind as well + another smaller sub. They can all just support the main LFE sub.
REL's will go to the back where I have 2 x XTZ 3X12's. Should be a lot of output I hope, but at the moment it is not nearly enough. Movies like Blade Runner (intro) and Ready Player One compress and loose dynamics due to compression in current subs. For reference my room is 140m3 / 5000 cf.
Yes I hope so but I'm confident. I'm only struggling with the ports and their tuning:
I want the tuning frequency as low as possible for the extension, driver protection against over-excursion and the GD spike as far away as possible from 20Hz.
I want the (flared) ports as big as possible to prevent high air velocity/chuffing. OTOH smaller ports should give more driver protection at higher sound levels.
I don't want the ports to be too big to avoid first port resonance.
Anyway it'll be always be a compromise. Oh I just read that Dirac Live has or had a 10Hz HPF? That changes things...
Yes I like those SBA NERO-21SW1100D very much. My dual enclosures should give 107 dB/1W/1m in the midbass and they're indeed seriously loud. Will you make them sealed or ported?
At what levels do you play? I know these movies very well and they never caused problems here even at high level playback. OK I had the 2x bridged Crown XLS1002's going into protection on single B&C 21SW152's (700W/8 Ohm) with Tron Legacy but since I replaced them with a single bridged XLS2502 for both B&C (2400W/4 Ohm) this problem went away. Moving the curtain to 20Hz also helped.
Yes it seems that even multiple 12's don't cut it for larger rooms. Your 10x12" have a cone area of about 5000cm² and with 8x 21" you'll add another 13280 cm² Of course cone area still is no volume displacement but it still tells something. Right now I have 9700cm² for 120m³ and if I build the LCR and reclaim the old 15" I'll have 19300cm². Should be enough for ART
I want the tuning frequency as low as possible for the extension, driver protection against over-excursion and the GD spike as far away as possible from 20Hz.
I want the (flared) ports as big as possible to prevent high air velocity/chuffing. OTOH smaller ports should give more driver protection at higher sound levels.
I don't want the ports to be too big to avoid first port resonance.
Anyway it'll be always be a compromise. Oh I just read that Dirac Live has or had a 10Hz HPF? That changes things...
Yes I like those SBA NERO-21SW1100D very much. My dual enclosures should give 107 dB/1W/1m in the midbass and they're indeed seriously loud. Will you make them sealed or ported?
At what levels do you play? I know these movies very well and they never caused problems here even at high level playback. OK I had the 2x bridged Crown XLS1002's going into protection on single B&C 21SW152's (700W/8 Ohm) with Tron Legacy but since I replaced them with a single bridged XLS2502 for both B&C (2400W/4 Ohm) this problem went away. Moving the curtain to 20Hz also helped.
Yes it seems that even multiple 12's don't cut it for larger rooms. Your 10x12" have a cone area of about 5000cm² and with 8x 21" you'll add another 13280 cm² Of course cone area still is no volume displacement but it still tells something. Right now I have 9700cm² for 120m³ and if I build the LCR and reclaim the old 15" I'll have 19300cm². Should be enough for ART
120m3 is also a quite large room to fill. Going by a rule from a post on avsforum about ULFE score about 0.01 x room volume in cf is whats needed for insane levels of bass. So I would need 50 liters of displacement. That's a lot! I won't quite have that but I figured a combined displacement of around 25-30 liters. So I suppose in m3 it would be 0.42 x room volume in m3 = dispacement requirements. But again this is totally subjective I don't think I need 130dB at 10hz?
If the 21" Nero's turn out as I hope, I am considering another 8 in the rear, but I might consider LLT as well. I did mine sealed for now. If the woofer doesn't perform as I hope I can exchange it for something else and reuse the cabinets.
When going sealed I figure I need 2 x amount of subwoofers to compete with ported designs, however below tuning the sealed would win. The only downside to sealed, as I see it, is that you require more of them for similar output down low. So it becomes a cost issue. I think cabinet volumes are similar for similar output between sealed and ported, perhaps you can settle on a little smaller overall cabinets for similar SPL at very low bass.
Regarding how low I play, well I sit 5.5 meters from a rather large 5m wide 1.9:1 screen with a target curve that do favor some extra bass!
I believe I am mostly around -6 to -10 on the master volume, but I am not entirely sure, with DIRAC, that is 100% calibrated to the standard MV.
That 25hz and below bass is just really demanding on our subwoofers and it just takes a lot of air movement and the REL's aren't designed for that. They do however sound phenomenal when not pushed beyond their limits. But I think I will repurpose them for a stereo setup down the line and do some custom subwoofers for the back of my room once the test with the 8 x 21's are completed.
If the 21" Nero's turn out as I hope, I am considering another 8 in the rear, but I might consider LLT as well. I did mine sealed for now. If the woofer doesn't perform as I hope I can exchange it for something else and reuse the cabinets.
When going sealed I figure I need 2 x amount of subwoofers to compete with ported designs, however below tuning the sealed would win. The only downside to sealed, as I see it, is that you require more of them for similar output down low. So it becomes a cost issue. I think cabinet volumes are similar for similar output between sealed and ported, perhaps you can settle on a little smaller overall cabinets for similar SPL at very low bass.
Regarding how low I play, well I sit 5.5 meters from a rather large 5m wide 1.9:1 screen with a target curve that do favor some extra bass!
I believe I am mostly around -6 to -10 on the master volume, but I am not entirely sure, with DIRAC, that is 100% calibrated to the standard MV.
That 25hz and below bass is just really demanding on our subwoofers and it just takes a lot of air movement and the REL's aren't designed for that. They do however sound phenomenal when not pushed beyond their limits. But I think I will repurpose them for a stereo setup down the line and do some custom subwoofers for the back of my room once the test with the 8 x 21's are completed.
I'm filling up to 14 Hz 30 m3 with 4 x 12" in large sealed cabinets, corner loaded. 120m3 is not much, 120 m2 on the other hand with 2.5 to the ceiling would result in ~300dm3 which is large.
For ultimate low reproduction only IB manifolds are applicable, but in reality it is extremely hard to be implemented because you need to make/use a hole to another room/ceiling etc. The next best this in terms of quality is sealed, but needs to be large and it will have a lot of power needed. Good thing is that you can put many woofers. I personally prefer this.
But LLT is a valid option and If I have access to 21" I would try it.
No 130dB indeed is way too much. I'm already very happy with 115dB (THX reference level) I Just simulated LLT's (300L per driver and 11Hz tuning) with all 18's and 21's with amplifier power matched to their excursion limit and got these numbers:
1. Front sub = 4x Faital Pro 18XL1800 LLT: 10Hz = 118dB / 20Hz = 122dB
2. Right rear sub = 2x B&C 21SW152/8 LLT: 10Hz = 113dB / 20Hz = 117dB
3. Left rear sub = 2x SBA NERO-21SW1100D LLT: 10Hz = 109dB / 20Hz = 115dB
4a. Optional center rear sub = 4x Visaton TIW400 sealed: 10Hz = 98dB / 20Hz = 110dB
4b. Optional center rear sub = 4x Visaton TIW400 LLT: 10Hz = 107dB / 20Hz = 113dB (2x woofers in 300L instead of 1x)
This should sound very impressive with ART (and without destroying the structure of the house). So 8x sealed 21"+ 8x 21" LLT will give scary amounts of LFE
I just saw Rebel Moon on Netflix. I was barely able to watch till the end but the Atmos soundtrack sounded very powerful with lots of 20-30Hz content.
1. Front sub = 4x Faital Pro 18XL1800 LLT: 10Hz = 118dB / 20Hz = 122dB
2. Right rear sub = 2x B&C 21SW152/8 LLT: 10Hz = 113dB / 20Hz = 117dB
3. Left rear sub = 2x SBA NERO-21SW1100D LLT: 10Hz = 109dB / 20Hz = 115dB
4a. Optional center rear sub = 4x Visaton TIW400 sealed: 10Hz = 98dB / 20Hz = 110dB
4b. Optional center rear sub = 4x Visaton TIW400 LLT: 10Hz = 107dB / 20Hz = 113dB (2x woofers in 300L instead of 1x)
This should sound very impressive with ART (and without destroying the structure of the house). So 8x sealed 21"+ 8x 21" LLT will give scary amounts of LFE
I just saw Rebel Moon on Netflix. I was barely able to watch till the end but the Atmos soundtrack sounded very powerful with lots of 20-30Hz content.