CTH1524 Status
I finally got a couple of hours to start working on tapped horns again. If I get a minute I'll add ramps to the bulldog and retest it.
I also have to make a reverse engineering trip to look at some brazillian made 18" boxes that seem awfully heavy for a simple 18. They are well camoed so we have to open them up to see what they did and in turn determine if my dj friend will destroy them or not. They are birch so I assume a horn of some kind due to the weight.
Always fun looking at commercial stuff and learning new tricks.
The CTH1524 is the box I will be using. I am finding I have to simplify the design a little to make it buildable by mortals (myself included). I'll post the basic plans here or in that critical thread. A builder's guide is a bunch of work so I'll have to think about that one. Once the revised version prototype has been tested with both a 3015 and 4015 I'll post the results. This will be a no nonsense compromise box for live use. Right now its sweet with the 3015lf, It needs tweaks to make it work with both.
SO FAR....
I reworked the driver entry chamber from 5 pieces per side at tough angles down to two pieces per side. The first central support/horn flare is bieng reworked now into a funky little triangle to match the horn first stage to the full width stages.
There was and is now in the reworking stage a central tapered "keel" that acts as both the horn flare (so the sides can remain blissfully parallel), and a brace on three sides as well as a place to run the wires.
There is still a little wasted space in the center but there is no way to eliminate it without hurting performance or making the box unwieldy for mobile use. The bulldog is the no wasted space version. There will be a few funkies in there when it's done but they won't hurt anything and no one will see them. I don't plan on building a plexiglass sided one to win this years gold woodworking award.
I finally got a couple of hours to start working on tapped horns again. If I get a minute I'll add ramps to the bulldog and retest it.
I also have to make a reverse engineering trip to look at some brazillian made 18" boxes that seem awfully heavy for a simple 18. They are well camoed so we have to open them up to see what they did and in turn determine if my dj friend will destroy them or not. They are birch so I assume a horn of some kind due to the weight.
Always fun looking at commercial stuff and learning new tricks.
The CTH1524 is the box I will be using. I am finding I have to simplify the design a little to make it buildable by mortals (myself included). I'll post the basic plans here or in that critical thread. A builder's guide is a bunch of work so I'll have to think about that one. Once the revised version prototype has been tested with both a 3015 and 4015 I'll post the results. This will be a no nonsense compromise box for live use. Right now its sweet with the 3015lf, It needs tweaks to make it work with both.
SO FAR....
I reworked the driver entry chamber from 5 pieces per side at tough angles down to two pieces per side. The first central support/horn flare is bieng reworked now into a funky little triangle to match the horn first stage to the full width stages.
There was and is now in the reworking stage a central tapered "keel" that acts as both the horn flare (so the sides can remain blissfully parallel), and a brace on three sides as well as a place to run the wires.
There is still a little wasted space in the center but there is no way to eliminate it without hurting performance or making the box unwieldy for mobile use. The bulldog is the no wasted space version. There will be a few funkies in there when it's done but they won't hurt anything and no one will see them. I don't plan on building a plexiglass sided one to win this years gold woodworking award.
Sounds like a complicated build.
Might be easier to take pics and use them as a diagram for the build how to.
Besides the single 12" 4.68 cubic feet (external)
TH's I have built. I haven't come up with anything better than a classic S shape horn. I have a single 15" design that is 140.88 Lt that is a classic S shape that is 99DB at 40, 105 at 50, 111 at 60 and 104 at 200 (2 Pi) At 30 inch's tall that is what I am trying to beat. Though I have a single 8" TH design I am thinking of building that hits 125 DB area at 50Hz and its ridiculously small at less than 50 Lt!
I have only come up with 1 design
that hits the 20 Hz w/ 130 DB output. But that is a large design split over 4 boxes minimum. I don't have the time or $ to try it out unfortunately.
You wouldn't happen to have a BP or HLBP design
to specially hit 40 Hz and below would you?
I plan on rebuilding my sound system
this next year and have to decide on with what and how. (wish I could get some Porn Horns!)
Might be easier to take pics and use them as a diagram for the build how to.
Besides the single 12" 4.68 cubic feet (external)
TH's I have built. I haven't come up with anything better than a classic S shape horn. I have a single 15" design that is 140.88 Lt that is a classic S shape that is 99DB at 40, 105 at 50, 111 at 60 and 104 at 200 (2 Pi) At 30 inch's tall that is what I am trying to beat. Though I have a single 8" TH design I am thinking of building that hits 125 DB area at 50Hz and its ridiculously small at less than 50 Lt!
I have only come up with 1 design
that hits the 20 Hz w/ 130 DB output. But that is a large design split over 4 boxes minimum. I don't have the time or $ to try it out unfortunately.
You wouldn't happen to have a BP or HLBP design
to specially hit 40 Hz and below would you?
I plan on rebuilding my sound system
this next year and have to decide on with what and how. (wish I could get some Porn Horns!)
Screamer: Good to hear it's coming on well. I imagine it will work ever better with 4015's...
I have 4 x 4012 drivers, I was wondering if they would work also (and how well they would work)? They have less cone surface area (SD), but the rest of the specs are pretty similar to the 4015.
I couldn't find any Hornresp screenies in this thread, otherwise I would've tried simming it myself.
I have 4 x 4012 drivers, I was wondering if they would work also (and how well they would work)? They have less cone surface area (SD), but the rest of the specs are pretty similar to the 4015.
I couldn't find any Hornresp screenies in this thread, otherwise I would've tried simming it myself.
Mike
On page 2 of this thread is the HTH115. The boxes I am building
are based on this one. The driver mounts inside the box instead of letting it's butt hang out in the breeze.
The HTH was 21", the CTH1524 is a 24" variant.
Getting the 3015 flat with an inductor was doable. I'm having a hell of a time trying to flatten out the 4015 or the BTX100.
Although they all will work in the box.
I gave up on below 38hz. Too big and you lose too much upper end. You would have to have a cab for below 60hz, and another for bass and midbass to make it work. Too many boxes for a live get in get out application. The CTH prototype rattles houses a block away. Good enough if the final buildable version performs as well.
On page 2 of this thread is the HTH115. The boxes I am building
are based on this one. The driver mounts inside the box instead of letting it's butt hang out in the breeze.
The HTH was 21", the CTH1524 is a 24" variant.
Getting the 3015 flat with an inductor was doable. I'm having a hell of a time trying to flatten out the 4015 or the BTX100.
Although they all will work in the box.
I gave up on below 38hz. Too big and you lose too much upper end. You would have to have a cab for below 60hz, and another for bass and midbass to make it work. Too many boxes for a live get in get out application. The CTH prototype rattles houses a block away. Good enough if the final buildable version performs as well.
CTH1524 data to play with
Here is the CTH1524 to play with.
CTH1524 translates to, Convertable Tapped Horn, 15" driver, 24" interior width. Convertable because you can mount the driver either way altering the mid bass articulation, or simply to save 80 bucks or more on a fancy grille.
REMEMBER this is the best compromise PORTABLE cabinet I could come up with for LIVE MOBILE USE at this time. It's easy to make it go lower or louder but forget about moving and packing 4 of them. The sims show 102.5 db avg. The prototype tested higher.
If anyone can make it smaller and still keep about 102-3db that would be awesome. A pair of them rattled a large concrete building over 500 feet away, 90 degrees from the cabs and on the otherside of another building.
Here's Akback and then a manual horn response export
I added both the 3015 and 4015 drivers to the manual Hornresp export at the bottom. Have fun. I've already beat it to death.
|DATA EXPORTED FROM HORNRESP - RESONANCES NOT MASKED
|COMMENT: CTH1524 final pa cabinet driver inside s1/s2...
|========================================================================================================
|REQUIRED AKABAK SETTINGS:
|File > Preferences > Physical system constants:
|Sound velocity c = 344m/s
|Medium density rho = 1.205kg/m3
|Sum > Acoustic power:
|Frequency range = 10Hz to 20kHz
|Points = 533
|Input voltage = 2.80V rms
|Integration = 2Pi-sr
|Integration steps = 1 degree ... 1 degree
|Integration method = Cross
|========================================================================================================
Def_Const |Hornresp Input Parameter Values
{
|Length, area and volume values converted to metres, square metres and cubic metres:
S1 = 619.00e-4; |Horn segment 1 throat area (sq cm)
S2 = 729.47e-4; |Horn segment 1 mouth area and horn segment 2 throat area (sq cm)
S3 = 2046.00e-4; |Horn segment 2 mouth area and horn segment 3 throat area (sq cm)
S4 = 2476.59e-4; |Horn segment 3 mouth area and horn segment 4 throat area (sq cm)
S5 = 3019.00e-4; |Horn segment 4 mouth area (sq cm)
L12 = 20.90e-2; |Horn segment 1 axial length (cm)
L23 = 178.90e-2; |Horn segment 2 axial length (cm)
L34 = 21.00e-2; |Horn segment 3 axial length (cm)
L45 = 24.00e-2; |Horn segment 4 axial length (cm)
|Parameter Conversions:
Sd = 881.00e-4; |Diaphragm area (sq cm)
}
|========================================================================================================
|Network node numbers for this tapped horn system:
| 0-Voltage-1
| |
| -Driver-------------
| | |
|8-Segment-9-Segment-10-Segment-11-Segment-12-Radiator
|========================================================================================================
Def_Driver 'Driver'
Sd=881.00cm2
Bl=18.60Tm
Cms=1.40E-04m/N
Rms=3.90Ns/m
fs=42.4464Hz |Mmd = 85.40g not recognised by AkAbak, fs calculated and used instead
Le=4.90mH
Re=5.30ohm
ExpoLe=1
System 'System'
Driver Def='Driver''Driver'
Node=1=0=9=11
Waveguide 'Horn segment 1'
Node=8=9
STh={S1}
SMo={S2}
Len={L12}
Conical
Waveguide 'Horn segment 2'
Node=9=10
STh={S2}
SMo={S3}
Len={L23}
Conical
Waveguide 'Horn segment 3'
Node=10=11
STh={S3}
SMo={S4}
Len={L34}
Conical
Waveguide 'Horn segment 4'
Node=11=12
STh={S4}
SMo={S5}
Len={L45}
Conical
Radiator 'Horn mouth'
Node=12
SD={S5}
...................................................
HERE IS THE EASY VERSION
CTH1524 Manual export for horn resp
Cabinet 40x30x24
S1 619.00
S2 729.47
S3 2046.00
S4 2476.59
S5 3019.00
L12 con 20.9
L23 con 178.9
L34 con 21.0
L45 con 24.0
3015 driver
SD 881
BL 18.6
CMS 1.40E-04
RMS 3.90
MMD 85.4
LE 4.90 (with coil)
RE 5.30
4015 Driver
SD 872.9
BL 18.50
CMS 1.06E-04
RMS 6.73
MMD 120.65
LE 5.40
re 5.40
.........................
IF you want to make it sound more ballsy, lower the mid bass slightly on your eq 70-90 and it will seem to have stronger low end. It's nice to have the ability to tweak the mid bass instead of trying to crank 40hz on a normal cabinet or folded horn.
You will see that the 4015 already has a 2-3 db dip in that region over the coil equipped 3015 which looks flat as a pancake.
I compared it to another proven DIY STD Horn box. The other box was louder at 1w, but the CTH beat it hands down at combat levels. Especially on the bottom end. Don't ask whose box, out of respect I won't tell.
I really like the angry sound these things make similar to a large bank of double 18's screaming away....but smaller. Should make those local band shows more exciting and hopefully help me make enough cash to buy 6 danleys in a couple of years.
Here is the CTH1524 to play with.
CTH1524 translates to, Convertable Tapped Horn, 15" driver, 24" interior width. Convertable because you can mount the driver either way altering the mid bass articulation, or simply to save 80 bucks or more on a fancy grille.
REMEMBER this is the best compromise PORTABLE cabinet I could come up with for LIVE MOBILE USE at this time. It's easy to make it go lower or louder but forget about moving and packing 4 of them. The sims show 102.5 db avg. The prototype tested higher.
If anyone can make it smaller and still keep about 102-3db that would be awesome. A pair of them rattled a large concrete building over 500 feet away, 90 degrees from the cabs and on the otherside of another building.
Here's Akback and then a manual horn response export
I added both the 3015 and 4015 drivers to the manual Hornresp export at the bottom. Have fun. I've already beat it to death.
|DATA EXPORTED FROM HORNRESP - RESONANCES NOT MASKED
|COMMENT: CTH1524 final pa cabinet driver inside s1/s2...
|========================================================================================================
|REQUIRED AKABAK SETTINGS:
|File > Preferences > Physical system constants:
|Sound velocity c = 344m/s
|Medium density rho = 1.205kg/m3
|Sum > Acoustic power:
|Frequency range = 10Hz to 20kHz
|Points = 533
|Input voltage = 2.80V rms
|Integration = 2Pi-sr
|Integration steps = 1 degree ... 1 degree
|Integration method = Cross
|========================================================================================================
Def_Const |Hornresp Input Parameter Values
{
|Length, area and volume values converted to metres, square metres and cubic metres:
S1 = 619.00e-4; |Horn segment 1 throat area (sq cm)
S2 = 729.47e-4; |Horn segment 1 mouth area and horn segment 2 throat area (sq cm)
S3 = 2046.00e-4; |Horn segment 2 mouth area and horn segment 3 throat area (sq cm)
S4 = 2476.59e-4; |Horn segment 3 mouth area and horn segment 4 throat area (sq cm)
S5 = 3019.00e-4; |Horn segment 4 mouth area (sq cm)
L12 = 20.90e-2; |Horn segment 1 axial length (cm)
L23 = 178.90e-2; |Horn segment 2 axial length (cm)
L34 = 21.00e-2; |Horn segment 3 axial length (cm)
L45 = 24.00e-2; |Horn segment 4 axial length (cm)
|Parameter Conversions:
Sd = 881.00e-4; |Diaphragm area (sq cm)
}
|========================================================================================================
|Network node numbers for this tapped horn system:
| 0-Voltage-1
| |
| -Driver-------------
| | |
|8-Segment-9-Segment-10-Segment-11-Segment-12-Radiator
|========================================================================================================
Def_Driver 'Driver'
Sd=881.00cm2
Bl=18.60Tm
Cms=1.40E-04m/N
Rms=3.90Ns/m
fs=42.4464Hz |Mmd = 85.40g not recognised by AkAbak, fs calculated and used instead
Le=4.90mH
Re=5.30ohm
ExpoLe=1
System 'System'
Driver Def='Driver''Driver'
Node=1=0=9=11
Waveguide 'Horn segment 1'
Node=8=9
STh={S1}
SMo={S2}
Len={L12}
Conical
Waveguide 'Horn segment 2'
Node=9=10
STh={S2}
SMo={S3}
Len={L23}
Conical
Waveguide 'Horn segment 3'
Node=10=11
STh={S3}
SMo={S4}
Len={L34}
Conical
Waveguide 'Horn segment 4'
Node=11=12
STh={S4}
SMo={S5}
Len={L45}
Conical
Radiator 'Horn mouth'
Node=12
SD={S5}
...................................................
HERE IS THE EASY VERSION
CTH1524 Manual export for horn resp
Cabinet 40x30x24
S1 619.00
S2 729.47
S3 2046.00
S4 2476.59
S5 3019.00
L12 con 20.9
L23 con 178.9
L34 con 21.0
L45 con 24.0
3015 driver
SD 881
BL 18.6
CMS 1.40E-04
RMS 3.90
MMD 85.4
LE 4.90 (with coil)
RE 5.30
4015 Driver
SD 872.9
BL 18.50
CMS 1.06E-04
RMS 6.73
MMD 120.65
LE 5.40
re 5.40
.........................
IF you want to make it sound more ballsy, lower the mid bass slightly on your eq 70-90 and it will seem to have stronger low end. It's nice to have the ability to tweak the mid bass instead of trying to crank 40hz on a normal cabinet or folded horn.You will see that the 4015 already has a 2-3 db dip in that region over the coil equipped 3015 which looks flat as a pancake.
I compared it to another proven DIY STD Horn box. The other box was louder at 1w, but the CTH beat it hands down at combat levels. Especially on the bottom end. Don't ask whose box, out of respect I won't tell.
I really like the angry sound these things make similar to a large bank of double 18's screaming away....but smaller. Should make those local band shows more exciting and hopefully help me make enough cash to buy 6 danleys in a couple of years.
Don't expect miracles Flip. They ain't even close to a Danley.
But they will replace my double cabs allowing me to run 3 cabs per side off a CA12 vs the current two double 15's off two TSU2002 amps or 3 single 18's off the CA12.
I only had an EP1500 to test the subs with and I only used one side.
The goal was to substitute single driver boxes for doubles.
The idea is to make the little shows sound as good as the big boys on a budget... and let the big boys do the big shows with big budgets. All in a practical ground stacked line array package that fits in a van and trailer and only needs a couple of 20 amp outlets to work if necessary.
I've already planned on building enough internal parts for 8 plus the unglued production prototype for reference.
But they will replace my double cabs allowing me to run 3 cabs per side off a CA12 vs the current two double 15's off two TSU2002 amps or 3 single 18's off the CA12.
I only had an EP1500 to test the subs with and I only used one side.
The goal was to substitute single driver boxes for doubles.
The idea is to make the little shows sound as good as the big boys on a budget... and let the big boys do the big shows with big budgets. All in a practical ground stacked line array package that fits in a van and trailer and only needs a couple of 20 amp outlets to work if necessary.
I've already planned on building enough internal parts for 8 plus the unglued production prototype for reference.
I think what screamers is looking for is exactly this... on a budget.
http://www.danleysoundlabs.com/pdf/TH 115 Spec Sheet.PDF
Actually if you could get a 3015lf to do 130db from 40-100hz in a 400liter cabinet.. that'd work.
I've tried for hours to sim a cabinet that can do that... it just comes up short every time. 102-103db from 40-100 2pi 1W/1M is easy... anything above that, seems next to impossible.
BTW, this is the best I've been able to come up with for that driver.
http://www.danleysoundlabs.com/pdf/TH 115 Spec Sheet.PDF
Actually if you could get a 3015lf to do 130db from 40-100hz in a 400liter cabinet.. that'd work.
I've tried for hours to sim a cabinet that can do that... it just comes up short every time. 102-103db from 40-100 2pi 1W/1M is easy... anything above that, seems next to impossible.
BTW, this is the best I've been able to come up with for that driver.
Attachments
JBell is right on target. That be the box I want for xmas 
Although clues on how to get close enough to it would be just as good
The CTH may hit your 130db mark. It was hitting 126 without enough power to really drive it. We'll see.
Actually 103 db from 38-120 was the goal.
The 3015 neo won't do it, more like 42-115 as you can see from the horn resp data I posted. I can get it to my goal but it's a 5 foot box! The CTH is quite acceptable for an uncompressed DIY box. The box has to be smaller than 42x30x26. The CTH is actually 39h x 25.5w x 30d outside dimensions.
I dumped the chambered version and integrated the chamber into s1 s2. s2 has to be high enough to fit the driver.
I also discovered that you can tweak s1 or s2 manually OUTSIDE the tapped horn wizard to tweak that midbass sag. If you try to put a tweaked version into the tapped wizard it will change back to the original.
I will try to play with one last box using compression, multiple split paths and possibly try to figure out multiple taps.
The CTH1524 buildable version should be ready to test in a couple of days.
Although clues on how to get close enough to it would be just as good
The CTH may hit your 130db mark. It was hitting 126 without enough power to really drive it. We'll see.
Actually 103 db from 38-120 was the goal.
The 3015 neo won't do it, more like 42-115 as you can see from the horn resp data I posted. I can get it to my goal but it's a 5 foot box! The CTH is quite acceptable for an uncompressed DIY box. The box has to be smaller than 42x30x26. The CTH is actually 39h x 25.5w x 30d outside dimensions.
I dumped the chambered version and integrated the chamber into s1 s2. s2 has to be high enough to fit the driver.
I also discovered that you can tweak s1 or s2 manually OUTSIDE the tapped horn wizard to tweak that midbass sag. If you try to put a tweaked version into the tapped wizard it will change back to the original.
I will try to play with one last box using compression, multiple split paths and possibly try to figure out multiple taps.
The CTH1524 buildable version should be ready to test in a couple of days.
CRASH AND BURN... AAARRRGGGGHHHH!!!!!
Dismal disappointing disheartening defeating failure.
The simplified CTH sucks. No better than the other 20 plus boxes I've built and rebuilt. I checked against the bulldog to make sure
the test gear was set right and it was as the bulldog specs came in right on target. I set up the test box and the bulldog next to each other so I don't have to move the mic on most of my post bulldog tests. Where the heck did all that sound go??????
Apparently the first stage and woofer loading is the key.
By changing from a rather complicated woodworking nightmare to a more streamlined but theoretically equal path, the magic dissapeared. Apparently small changes make a huge difference.
The second stage of the horn did not change so the problem is from the driver through the first couple of feet. The phase issue at 115hz also moved to 105 hz.hmmmm.
I'll try one more thing before I reluctantly assemble another amp rack to drive double 15's and forget about buying Danleys in a year or two. No edge....No decent work... No new toys.
Since I bought plans and built new tops to replace my old homebuilt EAW/JBL (And now Meyer makes the same box) clones
I have lost most of my business due to problems with the new tops. I finally got that fixed by redesigning them but at a terrible cost. I'm really getting tired of looking at the inside of boxes instead of working.
Any suggestions on woofer loading would be really appreciated before I give up completely. Thanks.
Dismal disappointing disheartening defeating failure.
The simplified CTH sucks. No better than the other 20 plus boxes I've built and rebuilt. I checked against the bulldog to make sure
the test gear was set right and it was as the bulldog specs came in right on target. I set up the test box and the bulldog next to each other so I don't have to move the mic on most of my post bulldog tests. Where the heck did all that sound go??????
Apparently the first stage and woofer loading is the key.
By changing from a rather complicated woodworking nightmare to a more streamlined but theoretically equal path, the magic dissapeared. Apparently small changes make a huge difference.
The second stage of the horn did not change so the problem is from the driver through the first couple of feet. The phase issue at 115hz also moved to 105 hz.hmmmm.
I'll try one more thing before I reluctantly assemble another amp rack to drive double 15's and forget about buying Danleys in a year or two. No edge....No decent work... No new toys.
Since I bought plans and built new tops to replace my old homebuilt EAW/JBL (And now Meyer makes the same box) clones
I have lost most of my business due to problems with the new tops. I finally got that fixed by redesigning them but at a terrible cost. I'm really getting tired of looking at the inside of boxes instead of working.
Any suggestions on woofer loading would be really appreciated before I give up completely. Thanks.
That was dumb. I forgot to follow my own advice.....Nashua 324 metal duct sealing tape. Most of the levels came back once I sealed the box.....
Surprisingly, sealing one small slit in the front brought 42hz up about 3 db!. ?Wow??
The simplification process appears to have lost a couple of db below 50hz with a gain at 80 hz. I'll try to get it back.
It's running about 103db from 50-120 +-3db
Its running 96db at 42hz.
Its 10 db down (92db) at 40 with a 4015 driver. The 3015 appears to be about a db hotter.
The Bulldog got re-ramped and sealed. Turns out the 4015 fits inside like the CTH so that's a plus. It's running about 101db avg
+-2db from 45-120 with the driver inside the throat. The Bulldog
runs a touch better below 60hz with the same falloff at 42/40 as the CTH. I suffers above 60 by at least 3 db against the CTH.
A couple of Bulldogs (Mini-Bells) per side under 15" two way boxes
will probably work very well for most bands and DJ's. They will ride in the back of a Pickup truck quite well and are easy to stack.
The CTH will work with 12" 2 way boxes, especially small horns.
They are easier to move around but you'd be better with a van or trailer to transport them. Niether cabinet will fit in a Hatchback or a regular car in pairs. Bulldog/Mini-Bell plans will be up in a couple of days in a generic form.
Surprisingly, sealing one small slit in the front brought 42hz up about 3 db!. ?Wow??The simplification process appears to have lost a couple of db below 50hz with a gain at 80 hz. I'll try to get it back.
It's running about 103db from 50-120 +-3db
Its running 96db at 42hz.
Its 10 db down (92db) at 40 with a 4015 driver. The 3015 appears to be about a db hotter.
The Bulldog got re-ramped and sealed. Turns out the 4015 fits inside like the CTH so that's a plus. It's running about 101db avg
+-2db from 45-120 with the driver inside the throat. The Bulldog
runs a touch better below 60hz with the same falloff at 42/40 as the CTH. I suffers above 60 by at least 3 db against the CTH.
A couple of Bulldogs (Mini-Bells) per side under 15" two way boxes
will probably work very well for most bands and DJ's. They will ride in the back of a Pickup truck quite well and are easy to stack.
The CTH will work with 12" 2 way boxes, especially small horns.
They are easier to move around but you'd be better with a van or trailer to transport them. Niether cabinet will fit in a Hatchback or a regular car in pairs. Bulldog/Mini-Bell plans will be up in a couple of days in a generic form.
iand said:
I don't think the 4 ohm box will get any louder at full power than the 8 ohm will. I am assuming the same driver mechanics but with a 4 ohm coil. Since most people will probably only buy a pair of them, 4 ohm makes sense. Something to consider if you are fortunate enough to come across some used ones in auctions and plan on running more than a pair eventually.
screamersusa said:
Sorry I wasn't clear, I meant 3dB in apparent sensitivity not in maximum output level. A 4 ohm nominal speaker should really have its sensitivity quoted with 2V applied (1W equivalent) not 2.82V (2W equivalent).
Speccing the 4 ohm TH-115 at 106-110dB with 2.82V applied is slightly misleading (though some other manufacturers do it as well) which is kind of surprising for Danley, their specs are normally much more honest than the competition (and his speakers are usually higher performance) -- though the data sheet does make it clear that this is done, which is still more honest than many
I still have my suspicions that the spec for the TH-115 is a little bit optimistic in both sensitivity and maximum undistorted output, given the results achievable in Akabak and Hornresp and the real Xmax of the B&C driver, but this has never really been resolved -- which would mean that it's still better than anything else around, maybe just not quite as much better as it seems.
Ian
P.S. Even Tom has hinted that there may be a little bit of "creative massaging" of the specs to make them more comparable to the sometimes heavily optimistic specs of other manufactures...
The new Version does not only seem to use the 4 Ohm Version of the "old" B&C Speaker, it actually does have a slighlty different response (at least judging from the spec sheet). But it´s subtile
The Frequency plot ist derived from watts, not Volt, so it gives a better comparison between the two models.
Did somebody do some distortion measurements? I found THD to be much lower in the area above the "smooth response" of the sims (sorry for bad english). But since it was an indoor measurement, I´m not quite sure if some rattling in the hall is responsible.
The Frequency plot ist derived from watts, not Volt, so it gives a better comparison between the two models.
Did somebody do some distortion measurements? I found THD to be much lower in the area above the "smooth response" of the sims (sorry for bad english). But since it was an indoor measurement, I´m not quite sure if some rattling in the hall is responsible.
Sabbelbacke said:The new Version does not only seem to use the 4 Ohm Version of the "old" B&C Speaker, it actually does have a slighlty different response (at least judging from the spec sheet). But it´s subtile
The Frequency plot ist derived from watts, not Volt, so it gives a better comparison between the two models.
Did somebody do some distortion measurements? I found THD to be much lower in the area above the "smooth response" of the sims (sorry for bad english). But since it was an indoor measurement, I´m not quite sure if some rattling in the hall is responsible.
The spec sheet says:
Nominal Impedance ............................................... 4 ohms
Sensitivity @ 1M ............................................. 106 dBSPL
112 dBSPL @ 100Hz max
(Referenced to 2.83V @1M ½ space, measured as 28.3V @ 10M)
which agrees *exactly* with the frequency response plot.
However the label on the response plots says "100W at 10m half-space", which seems wrong, 28.3V into 4 ohms nominal is obviously 200W.
Ian
P.S. Zmin=5 ohms is actually close to a nominal 8ohm load