Spherical Speaker Enclosure for Fostex P650K (Beta)

Designer

euxnas

Designer relation

Ingen

Kategori

Audio

Licens

Creative Commons Attribution NonCommercial Creative Commons - Attribution - Non-Commercial

$ ↺

Attribution påkrævet; kommerciel brug er ikke tilladt.

Designer commercial

None

Først set

2026-07-12 10:14

Sidst set

2026-07-16 20:20

Tags

65CM audio desktop DIY audio Fostex full range hifi P650K speaker speaker enclosure sphere spherical

Beskrivelse

A fully 3D-printed spherical sealed enclosure for the Fostex P650K full-range driver. Designed for a clean, natural, vocal-focused sound on a desktop. The seamless sphere hides all fasteners — a threaded equatorial joint and a clamping grille mean no screws are visible from the outside. ⚠️ Beta release. Fully functional, but a few things are still being refined (see Known Issues). Feedback welcome. Features 128 mm sphere — compact and desktop-friendly (stand adds a little height) Spherical shape minimizes edge diffraction and internal standing waves Sealed design, ~0.6 L effective internal volume No visible screws — threaded equatorial joint + clamping grille Multi-part, multi-color friendly (body / grille / stand / feet) Tuned for clear midrange and vocals rather than deep bass Files / Parts 01a_Front-Enclosure_Standard.stl — Front, standard clearance ×1 (default — choose one front) 01b_Front-Enclosure_Tight.stl — Front, tight clearance ×1 (choose one front) 02_Rear-Enclosure.stl — Rear enclosure ×1 03a_Grille_Embedded-Nut.stl — Grille, embedded-nut version ×1 (choose one grille) 03b_Grille_Side-Insert.stl — Grille, side-insert version ×1 (choose one grille) 04_Stand-Base.stl — Stand base ×1 05_Feet.stl — Feet: three feet joined by a ring, printed as one part ×1 SphericalSpeakerEnclosureforFostexP650K.3mf — Full project (uses the Standard front; all print settings included) Two front options — print only one: 01a Standard — generous clearance, assembles easily even if the print is slightly off. Recommended, and used in the .3mf . 01b Tight — minimal clearance for the best seal and a firm lock, but needs an accurately calibrated printer. It should seat with a few firm final turns; if it won't go, your print is running large — use the Standard front or run a flow calibration. Two grille options — print only one: 03a Embedded-Nut — the nut is embedded inside during printing. In the .3mf , this plate has a scripted print pause : the printer stops mid-print, you drop in the 4 nuts , then resume to finish. No supports, cleaner finish. (Recommended) 03b Side-Insert — push the nut in from the side after printing. Needs supports, but no pause required. Sourced parts (not printed) — per unit Exact parts depend on your wiring method — see the build guide. Fostex P650K driver ×1 Gold-plated brass speaker binding posts, M4 mounting shaft ×2 (one +, one −) — the rear has Ø4.2 mm mounting holes for this type; larger posts need the holes enlarged M4 × 12 mm screws ×4 and M4 nuts ×4 (driver mounting) Internal wire: AWG18, 20 cm ×2 Faston (spade) terminals for the driver: #110 female (−) and #205 female (+) Damping: felt (speaker damping sheet) + a little polyester wool Double-sided tape to fix the damping material Print settings Walls: 5 perimeters Infill: 20% (gyroid) Recommended filament: Bambu PLA (Basic / Matte / Silk all verified) Tested on: Bambu Lab P1S with the textured PEI plate STLs are already oriented for printing; the .3mf has everything set up for Bambu Studio Supports — differs per part: 02_Rear-Enclosure — supports on , with the overhang threshold set to 28° 03b_Grille_Side-Insert — supports on (default threshold is fine) All other parts — no supports needed Print pause (03a grille): The .3mf for the 03a grille has a scripted pause . When the printer stops, insert the 4 M4 nuts into the pockets, then resume the print to seal them inside. Assembly (short version) Check the thread fit — stiff on the first turn, but it beds in after a few in/out cycles; a firm final push seats it Mount the terminals to the rear (seal with a gasket or caulk) Place damping — felt on the lower inner wall, a little wool in the center (keep it clear of the cone) Mount the driver — crimp the faston terminals and connect the wiring (pre-twist it opposite to the closing direction), then clamp the driver between the grille and the front part Join the enclosure — screw front and rear together at the equator; press firmly at the end to seat it Assemble the stand — snap the one-piece feet ring into the stand base Set it up — place the sphere on the stand 👉 Full illustrated build guide: note.com/euxnas Known Issues (Beta) The inner thread surface prints a little rough (overhang without support). It's not visible and doesn't affect function. The threaded joint is sensitive to filament and print accuracy — even color and lot can matter. If the fit is too tight, use the Standard front, run a flow calibration, or test-print the thread section first. About the driver / What's next The Fostex P650K is an inexpensive 6.5 cm full-range driver — a great, low-cost way to try a small full-range build. This enclosure started as a prototype platform for it. I'd love to make a version for the Fostex FE83NV2 (8 cm) down the road — no promises on timing, but that's the direction I'm hoping to go.