technotic
Professional Amateur
Hello,
As I'm new here, I'll go ahead and fill out "The List" first off.
Vehicle : Ford Focus ZX4 (Sedan) 2005
Location in the vehicle: Trunk (back seats fold down)
Space available (Length x Width x Height): 18 inch to lowest point on rear deck. 27 degree backward slant, bottom to top (rear seats), ~ 36 inches inside wheel wells (narrowest point directly below rear deck), ~ 48 inches from bottom of seat slant to trunk trim, ~ 22 inches height behind rear deck. Slanted surface height is ~ 20 inches.
Subwoofer make and model: 1x CT Sounds TROPO 18 D4 (dual voice coil @4ohms each)
Subwoofer Size: 18 inch
Number of Subwoofers: 1
Type of Port (Kerfed, Slot, Aero, etc.): Considering slotted or bandpass
What type of music do you like?: EDM. I like catchy rap/pop/hip hop with good bass lines
Is your goal SPL or Everyday Music?: Aiming for manufacturer SPL spec, but non comp. So every day music
Tuning Freq (Hz): 28hz (mfg SPL spec)
Volume : 6.5ft^3
Amp: Audio Acoustik RZR1-2500D (class D monoblock, 650w RMS, 2500w "peak")
Head Unit: Pioneer AVH-5800BHS
Sub Specs from manufacturer:
18 Inch Dual 4 Ohm Coil Configuration
RMS Power: 650 Watts
MAX Power: 1300 Watts
3 Inch - 4 Layer High-Temperature Copper Voice Coil
Y30 Graded Double Stacked Ferrite Magnet
Competition Mega Foam Surround
Composite Paper with 3% Carbon Fiber Reinforcement
Signature Chrome Plated Low Carbon Iron Bottom Plate
Advanced Air Cooling System
Dual Round Weaved Copper Tinsel Leads
12 Gauge Push Terminals
Fs: 23.40 Hz
Qms: 5.02
Qes: 0.89
Qts: 0.75
Vas: 193.53 L
Cms: 0.11 mm/N
Mms: 434 gr
Sd: 1134 cm²
Re: 1.68
Le: 0.96
BI: 11.00 n/a
Sensitivity: 88.51 dB
Xmax: 13mm (one-way)
Misc: 4x Rockford Fosgate 5x7 (2 front, 2 rear deck) 2-way direct off head unit.
Installation details: going to do Big 3 upgrade with 1/0 gauge OFC. 1/0 gauge OFC positive to distro block under hood (4x 4 gauge ANL fused slots, as I want to add an SAE connector for my charger and jump starter unit, and a USB/rocker switch power panel below CC cluster. may change distro block though and put in-line quick disconnect to rear power run to allow air gap if charging/jumping), 1/0 gauge OFC to trunk into a 2-way reducer distro block, 4 gauge OFC to amp with a 4-to-8 gauge reducer adapter (amp power input is 8 gauge, dual 25a fuses), 4 gauge OFC ground using 4-to-8 reducer same as power.
Questions:
So I added a few extra details to "The List" but it may or may not be relevant.
I had been eyeing the CT Sounds TROPO 18 D4 (standard price: 179.99 USD) and CT had it on sale for a few days for 140. So I bought it, got it today. I figured I would build my own enclosure to optimize trunk space and tuning. This will be my first custom box build but I've been doing research. I intend to use 3/4 inch cabinet B grade plywood instead of MDF. I just built out a big wall cabinet with same stock (but walnut veneered) and found no voids or issues. Plan to treat with boiled linseed oil and polycrylic on inside face and contact cement some upholstery on outside. I planned on using pocket holes to join each panel with silicone sealer along every seam and in pocket holes, as well as using it as a gasket for the speaker terminals panel and speaker bezel. I intend to wire the voice coils as parallel "home runs" from terminal panel to each connector. My research seems to indicate that good quality plywood of 3/4 inch is superior to 3/4 inch MDF due to density and rigidity and less absorption.
I originally considered a sealed box @ 4ft^3 (mfg SPEC) but changed my mind. I'm now planning on going ported slot (mfg spec is 40ft^2 port area, and 6.5ft^3 tuned @28Hz from their SPL spec data). Tonight though, I also got curious about maybe doing a bandpass enclosure, but I haven't figured out WinISD yet (just installed last night) and subbox.pro only provides basic sealed or ported enclosure designs. Based on subbox.pro, entering all the mfg specs it asks for and giving a height of 20 inches and width of 36 inches, it gave me the following design:
20" x 36" x 20.85"
Front port slotted:
Side port slotted:
These don't have braces (not sure if I need them?) And the design options are only squared edges.
So first real question is, is slanting the front panel/baffle at 27 degree acceptable, which will allow 20 inches height so the sub can mount in the face at an angle? I considered using a 24" x 24" panel cut down to 20" x 24" for the sub mount, then overlapping 2 inches on each side with 20" x 8" pieces (with overlaps, 8" (6" + 2" OL) + 20" (24" -2" OL left, -2" OL right) + 8" (6" + 2" OL) = actual width 8" + 20" + 8" = 36". The main speaker panel in the center would be behind the 8" side panels too, which would make the speaker slightly recessed to hopefully reduce the risk of cone damage if the front side of the box were to bump something like a wall. I don't know it it would be too complex to then have the top panel 12" in depth to clear the rear deck and the another height extension by 4 inches to bring height total to 22". I can also expand width above the wheel wells by 6" on each side, starting at ~ 8" height from bottom..
maybe I'm making this way too complex to maximize space. Okay, so let's go with, can I slant the front panel at 27 degrees, and go flat on the back? Or if I put a second angle in at that point, to incline enough to give a 20" back, and then mount the speaker facing back? Or arrange it with the speaker firing up?
As for the port slot.. would side firing be the right way to go or front firing (or if the sub faced up, then port firing toward front of vehicle)?
I'm willing to put the extra effort into customizing the shape to expand over the wheel wells and such, to keep as much trunk space as I can. I don't suppose it would work having the speaker height at say 15 inches, up against the seats almost but facing upward, with the box dropping down and shallow but wide and long, the minimum height to reach the full volume with the port at the opposite end from the speaker?
Sorry if I seem to be getting far too specific. I don't expect it but anyone with experience creating unique custom boxes like I'm describing is interested in giving me a little of their time and knowledge to help me create something like the odd shapes I've mentioned, I would be hugely grateful. I can always do something functional for now and take my time building the custom custom enclosure.
Sorry if I've confused or lost you guys with my rambling. I don't expect anyone to answer all of these. The important questions are regarding the sloped front panel for the speaker and how to beat shape that, whether to mount the speaker forward, rear, or up, and the recommended port location to match.
Lastly, any input on the idea of building a bandpass box instead? My research says that they are pretty unforgiving to design errors, but I'm sure there's a proper schematic somewhere that would be appropriate for my environment. I'm still doing research on these.
Sorry for such a long and partially confusing post, but I do appreciate any feedback and anyone willing to take the time to share their knowledge and expertise with me. You guys have far more experience than I'm sure I will ever dedicate myself to learning as in-depth, and I respect that. Thanks in advance.
Tech
As I'm new here, I'll go ahead and fill out "The List" first off.
Vehicle : Ford Focus ZX4 (Sedan) 2005
Location in the vehicle: Trunk (back seats fold down)
Space available (Length x Width x Height): 18 inch to lowest point on rear deck. 27 degree backward slant, bottom to top (rear seats), ~ 36 inches inside wheel wells (narrowest point directly below rear deck), ~ 48 inches from bottom of seat slant to trunk trim, ~ 22 inches height behind rear deck. Slanted surface height is ~ 20 inches.
Subwoofer make and model: 1x CT Sounds TROPO 18 D4 (dual voice coil @4ohms each)
Subwoofer Size: 18 inch
Number of Subwoofers: 1
Type of Port (Kerfed, Slot, Aero, etc.): Considering slotted or bandpass
What type of music do you like?: EDM. I like catchy rap/pop/hip hop with good bass lines
Is your goal SPL or Everyday Music?: Aiming for manufacturer SPL spec, but non comp. So every day music
Tuning Freq (Hz): 28hz (mfg SPL spec)
Volume : 6.5ft^3
Amp: Audio Acoustik RZR1-2500D (class D monoblock, 650w RMS, 2500w "peak")
Head Unit: Pioneer AVH-5800BHS
Sub Specs from manufacturer:
18 Inch Dual 4 Ohm Coil Configuration
RMS Power: 650 Watts
MAX Power: 1300 Watts
3 Inch - 4 Layer High-Temperature Copper Voice Coil
Y30 Graded Double Stacked Ferrite Magnet
Competition Mega Foam Surround
Composite Paper with 3% Carbon Fiber Reinforcement
Signature Chrome Plated Low Carbon Iron Bottom Plate
Advanced Air Cooling System
Dual Round Weaved Copper Tinsel Leads
12 Gauge Push Terminals
Fs: 23.40 Hz
Qms: 5.02
Qes: 0.89
Qts: 0.75
Vas: 193.53 L
Cms: 0.11 mm/N
Mms: 434 gr
Sd: 1134 cm²
Re: 1.68
Le: 0.96
BI: 11.00 n/a
Sensitivity: 88.51 dB
Xmax: 13mm (one-way)
Misc: 4x Rockford Fosgate 5x7 (2 front, 2 rear deck) 2-way direct off head unit.
Installation details: going to do Big 3 upgrade with 1/0 gauge OFC. 1/0 gauge OFC positive to distro block under hood (4x 4 gauge ANL fused slots, as I want to add an SAE connector for my charger and jump starter unit, and a USB/rocker switch power panel below CC cluster. may change distro block though and put in-line quick disconnect to rear power run to allow air gap if charging/jumping), 1/0 gauge OFC to trunk into a 2-way reducer distro block, 4 gauge OFC to amp with a 4-to-8 gauge reducer adapter (amp power input is 8 gauge, dual 25a fuses), 4 gauge OFC ground using 4-to-8 reducer same as power.
Questions:
So I added a few extra details to "The List" but it may or may not be relevant.
I had been eyeing the CT Sounds TROPO 18 D4 (standard price: 179.99 USD) and CT had it on sale for a few days for 140. So I bought it, got it today. I figured I would build my own enclosure to optimize trunk space and tuning. This will be my first custom box build but I've been doing research. I intend to use 3/4 inch cabinet B grade plywood instead of MDF. I just built out a big wall cabinet with same stock (but walnut veneered) and found no voids or issues. Plan to treat with boiled linseed oil and polycrylic on inside face and contact cement some upholstery on outside. I planned on using pocket holes to join each panel with silicone sealer along every seam and in pocket holes, as well as using it as a gasket for the speaker terminals panel and speaker bezel. I intend to wire the voice coils as parallel "home runs" from terminal panel to each connector. My research seems to indicate that good quality plywood of 3/4 inch is superior to 3/4 inch MDF due to density and rigidity and less absorption.
I originally considered a sealed box @ 4ft^3 (mfg SPEC) but changed my mind. I'm now planning on going ported slot (mfg spec is 40ft^2 port area, and 6.5ft^3 tuned @28Hz from their SPL spec data). Tonight though, I also got curious about maybe doing a bandpass enclosure, but I haven't figured out WinISD yet (just installed last night) and subbox.pro only provides basic sealed or ported enclosure designs. Based on subbox.pro, entering all the mfg specs it asks for and giving a height of 20 inches and width of 36 inches, it gave me the following design:
20" x 36" x 20.85"
Front port slotted:
Side port slotted:
Subwoofer box CT Sounds TROPO 18 SPL MFG SPEC PORT SIDE
18 inch subwoofer box design CT Sounds TROPO 18 SPL MFG SPEC PORT SIDE, ported box plan, 3D model. Net internal volume 6.50 cubic feet, port area 40.00 square inches, tuning frequency 28 Hz. Subwoofer box calculator online
subbox.pro
These don't have braces (not sure if I need them?) And the design options are only squared edges.
So first real question is, is slanting the front panel/baffle at 27 degree acceptable, which will allow 20 inches height so the sub can mount in the face at an angle? I considered using a 24" x 24" panel cut down to 20" x 24" for the sub mount, then overlapping 2 inches on each side with 20" x 8" pieces (with overlaps, 8" (6" + 2" OL) + 20" (24" -2" OL left, -2" OL right) + 8" (6" + 2" OL) = actual width 8" + 20" + 8" = 36". The main speaker panel in the center would be behind the 8" side panels too, which would make the speaker slightly recessed to hopefully reduce the risk of cone damage if the front side of the box were to bump something like a wall. I don't know it it would be too complex to then have the top panel 12" in depth to clear the rear deck and the another height extension by 4 inches to bring height total to 22". I can also expand width above the wheel wells by 6" on each side, starting at ~ 8" height from bottom..
maybe I'm making this way too complex to maximize space. Okay, so let's go with, can I slant the front panel at 27 degrees, and go flat on the back? Or if I put a second angle in at that point, to incline enough to give a 20" back, and then mount the speaker facing back? Or arrange it with the speaker firing up?
As for the port slot.. would side firing be the right way to go or front firing (or if the sub faced up, then port firing toward front of vehicle)?
I'm willing to put the extra effort into customizing the shape to expand over the wheel wells and such, to keep as much trunk space as I can. I don't suppose it would work having the speaker height at say 15 inches, up against the seats almost but facing upward, with the box dropping down and shallow but wide and long, the minimum height to reach the full volume with the port at the opposite end from the speaker?
Sorry if I seem to be getting far too specific. I don't expect it but anyone with experience creating unique custom boxes like I'm describing is interested in giving me a little of their time and knowledge to help me create something like the odd shapes I've mentioned, I would be hugely grateful. I can always do something functional for now and take my time building the custom custom enclosure.
Sorry if I've confused or lost you guys with my rambling. I don't expect anyone to answer all of these. The important questions are regarding the sloped front panel for the speaker and how to beat shape that, whether to mount the speaker forward, rear, or up, and the recommended port location to match.
Lastly, any input on the idea of building a bandpass box instead? My research says that they are pretty unforgiving to design errors, but I'm sure there's a proper schematic somewhere that would be appropriate for my environment. I'm still doing research on these.
Sorry for such a long and partially confusing post, but I do appreciate any feedback and anyone willing to take the time to share their knowledge and expertise with me. You guys have far more experience than I'm sure I will ever dedicate myself to learning as in-depth, and I respect that. Thanks in advance.
Tech