3D Printed Audio Source Switch and Volume Control Boxes

DOWNLOAD Version 1.1 (2020-06-09) ZIP ~11MB

• Intro • Updates • Parts • Tools • PETG Filament • Printing Settings • STL Files

INTRO

Below you will find parts and tools, which will help you to print and assemble audio source switch and volume control boxes. If you noticed mistakes, have questions or suggestions, know better component (available in EU and US), please write or send link to info@jocys.com • Project page: Jocys.com/switch

Parts were printed from PETG with Prusa3D i3 MK3 Printer. If your printer is not precise enough, printed parts may not fit into each other and may not look good.

If you made your own updates or (file) changes, related to this project, please send me a link. I will add this link to your work on this page.

Why I decided to make my own switch? Ground wires of both audio sources in many available to buy switches are connected together. Maybe this works perfectly in theory and manufacturers can use more available switches with less poles, but in reality this often creates audio noise. People use Ground Loop Noise Isolators to eliminate that noise. I wanted signal to go through Ground Loop Noise Isolator, when both audio sources are connected only. I wanted to merge and separate both audio sources easily with button. Also, I wanted to switch stereo microphone and headphones at the same time with ability to switch off microphone with button. With stereo microphone you can have better environment noise elimination options. I didn’t want to use powered audio mixers or interfaces, which processes (distorts) signal in any way.

UPDATES

1.0 (2020-06-06) • Released
1.1 (2020-06-09) • Smooth shaft button added, knurled removed. Knobs redesigned to hide screw hole and to reduce ZIP from 67 to 11 MB.

PARTS

ROTARY SWITCH FOR AUDIO SOURCE SWITCHING

Taiwan Alpha • CTS • Bourns • Find on: Mouser (EU) • Digi-Key (US)

Taiwan Alpha • SR2511F-0602-19R0B-E9-N-W-159

Taiwan Alpha rotary switch to switch between audio sources.

I would not recommend to buy cheap Chinese rotary switches. They are, usually, made from softer metal and after several dozen switches lose switching smoothness. I didn't test Grayhill 2 deck (3 poles per deck) switches.

Series: SR2511F
Product Category: Rotary Switches
Number of Positions: 2 Position
Number of Decks: 1 Deck
Number of Poles per Deck: 6 Pole
Current Rating: 300 mA
Voltage Rating AC: 125 VAC
Index Angle: 0 deg
Contact Style: Non-Shorting (Non-Shorting / Break-Before-Make)
Termination Style: Solder Lug
Thread Size: M9xP0.75 (9mm)

Audio Source Switch Box Diagram

Audio Source Switch Box Diagram.

3 x Taiwan Alpha • SR2511F Rotary Switch
6 x EST Marushin • MJ-073H 3.5mm 3 Pole Jack Socket
2 x EST Marushin • MP-012LN 3.5mm 3 Pole Jack Plug

ROTARY POTENTIOMETER FOR VOLUME CONTROL

Taiwan Alpha • CTS • Bourns • Find on: Mouser (EU) • Digi-Key (US)

Bourns • PTD902-1015K-A102

Sennheiser uses 500Ω potentiometer in HZR 62 volume control for HD 62 TV 32Ω headphones. Creative uses 1000Ω (1KΩ) potentiometer in Volume Control Module for Sound Blaster Zx. 10000Ω (10KΩ) potentiometers are too strong for Sennheiser HD 598 50Ω headphones.

Bourns rotary potentiometer for volume control box.

Series: ProAudio PTD90 (9mm)
Resistance: 1 kOhms
Taper: Audio
Number of Turns: 1 Turn
Number of Gangs: 2 Gang
Element Type: Carbon
Tolerance: 10 %
Thread Size: M7xP0.75 (7mm)
Shaft Type: Knurled / Serrated
Shaft Diameter: 6 mm
Shaft Length: 15 mm
Termination Style: Through Hole
Mounting Style: Panel Mount
Life: 15000 Cycles
Power Rating: 25 mW
Voltage Rating: 20 VDC, 150 VAC

Taiwan Alpha • CTS • Bourns • Find on: Mouser (EU) • Digi-Key (US)

Taiwan Alpha • RV24BF-10-15R1-A1K-LA

Alternative... Taiwan Alpha rotary potentiometer for volume control box. Use "Spacer from 9mm to 8mm Hole" from "Spacers.STL" file to centre potentiometer. Not so precise, easy to turn and smooth as Bourns PTD90 potentiometer.

Series: RV24BF (24mm)
Resistance: 1 kOhms
Taper: Audio
Number of Turns: 1 Turn
Number of Gangs: 2 Gang
Element Type: Carbon
Tolerance: 20 %
Thread Size: M8x0.75 (8mm)
Shaft Type: Smooth
Shaft Diameter: 6.35 mm
Shaft Length: 15 mm
Termination Style: Solder Lug
Mounting Style: Panel Mount
Life: 15000 Cycles
Power Rating: 500 mW (1/2 W)
Voltage Rating: 250 V

Volume Control Box Diagram

Volume Control Box Diagram.

1 x Taiwan Alpha • RV24BF or Bourns • PTD90 Rotary Potentiometer
2 x EST Marushin • MJ-073H 3.5mm 3 Pole Jack Socket

3.5MM 3 POLE JACK SOCKET

EST Marushin • MJ-073H ( CPC Farnell • UK Farnell • US Newark )

3.5mm 3-Pole Panel Mount Jack Socket

Manufacturer Part No: MJ-073H
No. of Contacts: 3 Contacts
Gender: Socket
Pin Diameter: 3.5mm
Connector Mounting: Chassis Mount
Contact Plating: Gold over Nickel Plated Contacts
Connector Body Material: Plastic Body

EST Marushin • MJ-074N ( CPC Farnell • UK Farnell • US Newark )

Alternative... 3.5mm 3-Pole Panel Mount Jack Socket

Manufacturer Part No: MJ-074N
No. of Contacts: 3 Contacts
Gender: Socket
Pin Diameter: 3.5mm
Connector Mounting: Chassis Mount
Contact Plating: Nickel Plated Contacts

3.5MM 3 POLE JACK PLUG

EST Marushin • MP-012LN ( CPC Farnell • UK Farnell • US Newark )

3.5mm 3-Pole Panel Mount Jack Socket - for connecting Ground Loop Noise Isolator inside Audio Source Switch Box.

Manufacturer Part No: MP-012LN
No. of Contacts: 3 Contacts
Gender: Plug
Pin Diameter: 3.5mm
Connector Mounting: Cable Mount
Contact Plating: Gold Plated Contacts
Connector Body Material: Plastic Body

AUDIO JACK EXTENDER

Amazon • 3.5mm Audio Jack Extender 3 inch (7.6mm)

If you will use "Volume Box B" attached to a leg table, I would recommend to use short 3.5mm Audio Jack Extender. If you will forget, that you are wearing headphones, and will move from the table... before damaging headphones or "Volume Box B" disconnection from its holder, extender will bend and headphones will disconnect first.

GROUND LOOP NOISE ISOLATOR

Neoteck • Ground Loop Noise Isolator

If you will use "Audio Source Switch Box" and will merge audio sources with right button (to hear both computers at the same time), grounds of booth sources will be connected together. In some cases this can introduce background audio noise. To eliminate that noise, you can fit inside Ground Loop Noise Isolator. I used one by Neotec (it fits inside the box).

Eliminates Hiss, hum, and other background interference, caused by ground loop noise.
For any audio devices that has 3.5mm audio jacks, like car audio system, home stereo, PC, laptop, speaker.
Compact size makes it easy to carry around.
Easy installation, no extra setup. All you need to do is to plug it in.
Contents: Vinteam ground loop isolator, 3.5mm audio cable, user manual, 18-Month product replacement warranty.

CABLES

12voltplanet • Single 0.5mm² 11A

50m Reel of Single 0.5mm² 11A - Black (ground), Red (right), White (left).

Manufactured to: ISO 6722:2006 (Class B)
Voltage rating: suitable for 12V & 24V systems (60V max.)
Nominal current rating: 11A
Maximum loading: 132W@12V, 264W@24V
No./size of conductors: 16/0.20mm
Conductor cross section: 0.5mm2
Maximum overall cable diameter: 1.7mm
Resistance per m at 20oC: 0.0371 Ω
Conductor material: Plain copper
Insulation material: PVC (hard grade)
Working temperature range: -40oC to +105oC (with brief excursions up to +120oC)

BUMPER STOPS

BumperStops • Affixit • Cylindrical Bumper Stops PD.2120BSHEET

4 x anti slip bumper stops for each box.

PD.2120 Cylindrical Bumper stops - 10.1mm x 1.8mm
288 Bumper Stops per Sheet (Priced per Sheet)
Material: Polyurethane
Adhesive: Black Bumper stops have a Rubber Adhesive.
Service Temperature for Black Bumper stops: -20 °C to 70°C

Anti Slip
Anti Scratch
Anti Vibrate
Absorbs Shock
Dampens Sound

SCREWS AND NUTS

Accu • M3 x Cap Head Screw (DIN 912)

M3 10mm Cap Head Screws for IKEA OLOV adustable leg holder (3).

M3 (3mm) Thread Size (T)
3mm Head Length (H)
1.3mm Hexagon Depth (P)
2.5mm Hexagon Socket A/F (J)
DIN 912 Manufacturing Standard
10mm Length (L)
+/- 0.13mm General Tolerances
Yes Fully Threaded
12.9 Hardened Steel Material
12.9 Hardened Steel Material Specification
0.5mm Screw Thread Pitch
Self Colour Finish
5.5mm Head Diameter (D)
10mm or 18mm Thread Length (Max)

Accu • M3 8mm Cup Point Grub Screw (DIN 916)

M3 8mm Cup Point Grub Screw for knobs (1).

Cup Diameter: 1.15mm-1.4mm
Finish: Chemical Matte Black
Length: 8mm Manufacturing Standard: DIN 916
Material: A4 Stainless Steel (Black)
Min Socket Head Depth: 1.2mm
Pitch: 0.5mm
1.5mm (1.52mm-1.58mm) Hexagon Socked (1)
Thread Size: M3 (3mm)

Accu • M3 Square Nut (DIN 562)

M3 Square Nuts for knobs (1).

Finish: Chemical Matte Black
Manufacturing Standard: DIN 562
Material: A4 Stainless Steel (Black)
Pitch: 0.5mm
Thickness: 1.8mm
Thread Size: M3 (3mm)
Width: 5.5mm

Accu • M3 Hexagon Nut (DIN 934)

M3 Hexagon Nuts for IKEA OLOV adustable leg holder (3).

DIN 934 Manufacturing Standard
5.32mm - 5.50mm Nut Width A/F (F)
0.13mm General Tolerances
A4 Stainless Steel - Black Material
A4 Stainless Steel Material Specification
Chemical Matte Black Finish
6.01mm Nut Width A/P (C)
0.5mm Thread Pitch
M3 (3mm) Thread Size
2.15mm - 2.40mm Nut Thickness (T)

KNOBS (OPTIONAL)

Kilo International • OEJA-90-4-5 Knob

These knobs look good for volume control. Make sure, shaft diameters on knob and potentiometer are the same (6mm or 6.35mm).

Model: OEJ
Indicator: (L)line, (A)arrow, (NI)no ind.
Diameter: (50)0.500", (63)0.625", (75)0.750", (90)0.920"
Finish: (1)clear gloss, (2)black gloss, (3)clear matte, (4)black matte
Shaft Size: (5)0.250"(6.35mm), (6)0.125", (7)0.2375"(6mm)

VELCRO (OPTIONAL)

Velcro • One-Wrap Reusable Ties 10mm x 5m

10mm x 5m - Black - For tying Volume Box B to something with "Volume Control Box B Bottom" part for Velcro.

Velcro • Heavy Duty Stick On Tape 50mm x 1m

50mm x 1m - Black - For sticking Volume Box B to something with "Volume Control Box B Bottom" part for Velcro.

VELCRO® Brand Stick On fasteners are ideal for smooth surfaces and can be used indoors or outside. They are available in squares, coins, strips, and tapes and come in a range of colors.

1. Clean and dry surface before application
2. Peel tape from fastener and press firmly into place
3. Adhesive reaches maximum strength after 24 hours

TOOLS

3D PRINTER

Prusa • i3 MK3 3D Printer

• Print technology: Fused Filament Fabrication / Fused Deposition Modeling.
• 0.4mm nozzle (easy changeable) for 1.75 mm filament.
• Build volume 11,025 cm3 (25 x 21 x 21 cm).
• Layer height (layer resolution) from 0.05 mm (50 microns).
• Accuracy: 0.01 x 0.01 x 0.005 mm (10 x 10 x 5 microns).
• Max extruder temperature: 280 °C.
• Max heated bed temperature: 120 °C.
• Supported materials: PLA, ABS, PET, HIPS, Flex PP, Ninjaflex, Laywood, Laybrick, Nylon, Bamboofill, Bronzefill, ASA, T-Glase, Carbon-fibers enhanced filaments, Polycarbonates...

SOLDERING TOOLS

Weller • BP865CEU

Weller • PU 81

For soldering wires to potentiometer and switch.

Weller • Tip-Activator

For regeneration of oxidized tips. Cleaning only possible in hot state of the soldering tip.

Weller • WP 65 Set

WP 65 - Soldering iron 65 W, 24 V with Power-Response Heating Technology.
XNT A - Soldering tip chisel 1,6 x 0,4 mm.
WDH 10 - Safety rest with Stop+Go function and dry cleaner.

Weller • EL60/40-100

Kester • 44 Flux-Cored Wire

Sn60Pb40 - 0.8mm - 3.3% Flux - melting range 183-190°C
Sn63Pb37 - 0.8mm - 3.3% Flux - melting point 183°C

SCREWDRIVERS

Wera Tools • Series Kraftform Micro 2054 (05118066001)

For M3 cup point grub screws on knobs (DIN 916).

2054 Screwdriver (1.5mm) for hexagon socket screws for electronic applications.

High-quality steel micro screwdriver
Hex-Plus allows socket head screws to live longer
Power zone with integrated soft grip
Free spin cap
Anti-roll off
Corrosion protected
Chemical resistance

Wera Tools • Series Kraftform Micro 2054 (05118070001)

For M3 cap head screws (DIN 912) for IKEA OLOV adustable leg holder.

2054 Screwdriver (2.5mm) for hexagon socket screws for electronic applications.

High-quality steel micro screwdriver
Hex-Plus allows socket head screws to live longer
Power zone with integrated soft grip
Free spin cap
Anti-roll off
Corrosion protected
Chemical resistance

WIRE STRIPING AND CUTTING TOOLS

C.K Tools • 495001 Wire Stripper

Stripping: 0.2 - 6.0mm²;
Cutting: HRC 40 - 50;
Crimping: 0.5 - 6.0mm² insulated and non-insulated terminals

C.K Tools • Wire Stripping Pliers 3893

For safe and damage-free stripping of fine, insulated solid wires in applications where it is critical to prevent damage from electro-static charge. Suitable for cutting soft copper wires.

Six pre-set blade pairs for stripping the sheathing from insulated, solid core wires of 0.2, 0.3, 0.4, 0.5, 0.6 and 0.8mm (20-30 AWG).

C.K Tools • Side Cutters T3887

Precision side cutters for fine cutting applications Sharp, precision ground cutting edges with an extra full flush cut Suitable for cutting soft copper wires of up to 1.6mmØ / 14AWG Tapered and relieved head for access in narrow and confined spaces.

PETG FILAMENT

I would not recommend to print parts from ABS (shrinkage is too big) or PLA (low heat resistance).

I had no problems with these filaments:
Prusa3D • Jet Black Prusament PETG 1.75
MCPP • BasicFil Black PETG 1.75
Amazon • AmazonBasics Black PETG 1.75
3DPrintz • Black PETG 1.75

Brand	3DPrintz	Prusa3D (Prusament)	Amazon (MCPP)	Prusa3D (Filament PM)	Real Filament
Region	UK	Czechia	EU	Czechia	Netherlands
Overall (out of 10)	9.9	9.8	9.6	8.6	6.5
Color blackness-darnkness	9.4	9.6	10	9	6
Uniformity of surface glossiness: top (sides)	10	9 (10)	8 (9)	7 (8)	6
Stringing	10	10	10	8	6
Warping	10	10	10	10	8

PC Johnson • Windex Original Glass Cleaner
For preparing-cleaning heated printer bed... Spring Steel Sheet with Smooth Double-sided PEI before printing with PETG filament.

Water: Water
Cleaning Agent: 2-Hexoxyethanol, Isopropanolamine, Ammonium Hydroxide
Wetting Agent: Lauryl Dimethyl Amine Oxide, Sodium Dodecylbenzene Sulfonate
Fragrance: Fragrance
Dye: Liquitint® Sky Blue Dye

SHL • Isopropanol / Isopropyl Alcohol / IPA
NOTE: I didn't test-print parts for this project on Textured PEI Powder-coated Spring Steel Sheet.

For preparing-cleaning heated printer bed... Double-sided Textured PEI Powder-coated Spring Steel Sheet before printing with PETG filament.

For thin parts to stick correctly, you may need to adjust height of first layer perfectly and to reduce "Elephant foot compensation" from default value 0.2mm... to 0.1mm.

Modified settings: PrusaSlicer > Print Settings > 0.20 QUALITY MK3 > Advanced > Slicing...

Isopropanol 99.9% / Isopropyl Alcohol / IPA
Manufacturer Part Number: 1000-ISO-TRIGGER
Child Proof Cap
Natural Trigger spray cap for bottles with a 28mm neck (OFF, Spray, Stream)
1 Litre

Kleenex • Ultra Soft Pocket Tissues
For preparing-cleaning heated printer bed.

PRINTING SETTINGS

Printing Settings for 3DPrintz PETG Filament on PrusaSlicer
...for Spring Steel Sheet with Smooth Double-sided PEI

For BIG parts to stick on TEXTURED PEI Powder-coated Spring Steel Sheet sheet, I increased recommended bed temperature from 60-80°C (for AmazonBasic and MCPP BasicFill PETG filaments) to 85°C (First layer) and 90°C (Other layers). I printed BIG parts in my own Temperature Controlled Enclosure. Temperature inside enclosure was about +45°C with these bed settings.

Prusa3D • PrusaSlicer

Modified settings: PrusaSlicer > Filament Settings > Prusament PETG > Filament

• "Extruder: 220°C".
• "Bed: 80°C".

Modified settings: PrusaSlicer > Print Settings > 0.20 QUALITY MK3 > Layers and perimeters

• "Ensure vertical shell thickness: disabled" - I had problems with thin 45° hanging angles when it was enabled.
• "Perimeters: 3" - infill pattern is less visible on surface.
• Seam position: Rear - I printed most of the parts with "Rear" setting selected. It created line at the back of the parts, but front and side surfaces were perfectly smooth.

Modified settings: PrusaSlicer > Print Settings > 0.20 QUALITY MK3 > Inflill

• "Fill density: 80%".

Modified settings: PrusaSlicer > Print Settings > 0.20 QUALITY MK3 > Speed

• Reduced printing speeds (10-20-180-400). Slower speeds results in smoother and glossier surfaces without matte areas, reduces printing noise with vibrations... lesser probability for corners of big parts to unstick from heated bed, because of shrinking.
• "Travel: 180" - low speeds (like 20) creates surface blobs after long travel distances.
• "First layer speed: 10" - for better adhesion.

Modified settings: PrusaSlicer > Printer Settings > Original Prusa i3 MK3S > Custom G-code

• I added few lines to G-code to remove filament blob on nozzle right before printing starts and raised intro line to reduce wearing of steel sheet plate surface.

G1 Z50 ; ADDED LINE --- Z Up to clean filament blob from nozzle
G1 Z-50 ; ADDED LINE --- Z Down
G1 Z0.50 ; ADDED LINE --- Z Up for less intro line adhesion to prevent surface of steel sheet plate from wearing

STL FILES

For better quality and safety... I printed majority of parts separately.

To split group and to remove some parts:
1. Open “*.STL” file in PrusaSlicer Edition.
2. Click on [ Split to objects ] button.
3. Select parts one by one, which you don't want to print.
4. Press [ Del ] key on keyboard.

	You can edit STL files with free and open source 3D creation suite Blender.
	Import “*.STL” file: 1. Blender 2.8 > File > Import > Stl (.stl). If imported STL object is not visible: 1. Select imported object in “Scene Collection” list (top-right panel). 2. In “Object Mode“ (top-left drop-down) > Object > Set Origin > Geometry to Origin.

Switch_Box_Top.STL

1 x Audio Source Switch Box Top - Fill angle: 0°

Switch_Box_Bottom.STL

1 x Audio Source Switch Box Bottom - Fill and Bridging angle: 45°

Switch_Box_Parts.STL

1 x Lavalier Stereo Microphone Holder A - Fill angle: 90°
1 x Lavalier Stereo Microphone Holder B - Fill angle: 90°
1 x Lavalier Stereo Microphone Holder C - Fill angle: 90°
1 x Rotary Switch Plate (2)
1 x Rotary Switch Button (2) - Fill angle: 90°
1 x Audio Source Switch Box Back Plate with 8mm Holes
1 x Audio Source Switch Box Back Plate with 6mm Holes

Volume_Box_A.STL

1 x Volume Control Box A Bottom - Fill and Bridging angle: 45°
1 x Volume Control Box A Top - Fill angle: 0°
1 x Volume Control Box A Back Plate with 8mm Holes
1 x Volume Control Box A Back Plate with 6mm Holes

Volume_Box_B.STL

1 x Volume Control Box Back Plate with 8mm Holes
1 x Volume Control Box Back Plate with 6mm Holes
1 x Volume Control Box B Top - Fill angle: 0°
1 x Volume Control Box B Holder for IKEA OLOV adustable leg
1 x Volume Control Box B Bottom for Velcro - Fill and Bridging angle: 45°
1 x Volume Control Box B Bottom for Attachments - Fill and Bridging angle: 45°
1 x Volume Control Box B Desktop Plate - Fill angle: 0°

Knobs.STL

Knurled shaft has 18 teeth, so you can mount knurled knob in 20° angle fixed positions only. There is no space in Volume Control Box B to turn 24mm potentiometer. If you want to align knob to various angles, you can use different knob inserts.

For all parts: Seam position: Random

1 x Knob Cover - Fill angle: 0°
1 Line: Inserts for 15mm shaft (-4mm plate) - Alpha RV24BF Potentiometer (insert 1)
2 Line: Inserts for 15mm shaft (-2mm plate) - Bourns PTD902 Potentiometer (insert 3)
3 Line: Inserts for 20mm shaft (-4mm plate) - Alpha SR2511F Switch (insert 1)

Round shaft
Knurled shaft 0° - Knob arrow aligned with teeth spikes (0°).
Knurled shaft ±10° - Knob arrow aligned between teeth spikes (to rotate knob ±10°)
Knurled Shaft +5°, -5° - Knob arrow rotated 5° after or before teeth spikes (to rotate knob ±15° or ±5°).

Spacers.STL

1 x Spacer from 9mm to 7mm Hole - For Bourns PTD902 Potentiometer
1 x Spacer from 11mm to 7mm Hole
1 x Spacer from 11mm to 8mm Hole - For Alpha RV24BF Potentiometer

Audio Source Switch and Volume Control Boxes

0.2mm layer, 2 walls, 15% infill