SKU: 43857376679

LRB-303 DIY 303 Kit

Sale price$327.15 Regular price$363.50
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Ships within 48 hours · Estimated delivery Jul 11 - Jul 16

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Description

LRB-303 DIY 303 KitPLEASE READ There are a limited number of kits in stock. A second large batch has been ordered and will be ready to ship in 2 3 weeks so I am making those available to order now. Orders will fulfilled in the order received. If you are interested in an assembled device click here This a complete kit to build the LRB 303 synthesizer. This is NOT a beginner kit and some kit building skills are necessary. Boards are 4 layer FR4 ENIG plated and fully ROHS

PLEASE READ

There are a limited number of kits in stock.  A second large batch has been ordered and will be ready to ship in 2-3 weeks so I am making those available to order now.  Orders will fulfilled in the order received. 

If you are interested in an assembled device click here

This a complete kit to build the LRB-303 synthesizer.    This is NOT a beginner kit and some kit building skills are necessary.  Boards are 4 layer FR4 ENIG plated and fully ROHS Compliant.

Tools Required:

Soldering Iron 
Solder (ROHS SAC305 solder is used on the board)
Trimmer Adjustment Tool or Small Blade flat screw driver
Wire Strippers

BUILD GUIDE HERE (work in progress)

User Manual: https://github.com/djphazer/OS-303/wiki/User-Guide

Build Support can be found on the Discord Channel

This kit includes:

  • SMD populated LRB-303 Mainboard
  • SMD populated LRB-303 Switchboard
  • Alps Tact switches, LEDS, Standoffs
  • Switched DIN Socket
  • Mainboard Through hole parts (8 Pots, 2 Brackets, Slide Switch, Audio, DC, CV Jacks)
  • Precut and Tinned Ribbon Cables (4 Pcs)
  • Alps Rotary Switches
  • Precut interconnect wires
  • OS-303 Processor with MIDI harness
  • Dust Covers (4 pcs)
  • Rub-on Case Art Sheet
  • Metal Keyboard panel

NOT Included:

  • Knobs/ Button Caps.  Available from Krumptronics or Sound to Parts
  • Case AVAILABLE HERE

Case Ordering Instructions:

Any Material Can be used for the case however I recommend 9600 Resin with Spray Painted Surface finish.  That is proven good.  JLC will probably complain about wall thicknesses, tell them that you accept it as is.   Clear is cool however the material does not have great dimensional stability so warping with clear is possible, YMMV.  Make sure you select "Plastic Enclosure" as the application

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 43857376679

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Christy F
Pawtucket, US
★★★★★ 5
Great socks
Size: Medium, Color: Pink - 647
Well-made and comfortable to wear. Great for golf and other outdoor activities. Like them because they do not show above shoes.
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Reviewed in the United States on April 19, 2026
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Cait E
Bozeman, US
★★★★★ 5
These ACTUALLY stay put all day long - I was skeptical, but am so glad I took a chance on these
Size: Medium, Color: (014) Halo Gray / Halo Gray / Castlerock
I was so skeptical about whether these would stay on my feet all day without sliding down into my shoe - I’ve tried so many socks in the past with the silicone strip on the heel which failed. I’ve owned these for a couple months now and they have never slipped down - they stay put all day! I love the variety of colors to choose from, and the value per pack is great since six pairs come per pack (I thought it was only three when I first purchased and was pleasantly surprised by the additional pairs). They also have perfect thickness - not too warm to wear during the summer months with sneakers; I live in a tropical climate, though, so I’m not sure how they will do in cooler climates. I’ve washed each pair once or twice and the color and quality of the silicone has stayed so far (knock on wood). Overall: high recommend based on my experience so far!
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Reviewed in the United States on September 13, 2025
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Maggie Vega
Whiting, US
★★★★★ 5
Great fit!
Size: Medium, Color: (403) Washed Navy / Washed Navy / Blue Smoke
Great quality!
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Reviewed in the United States on May 15, 2026
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Kira Stewart
Alexandria, US
★★★★★ 5
My favorite socks
Size: Medium, Color: (659) Fuchsia Dusk / Fuchsia Dusk / Tourmaline Pink
Very comfortable. True to size. Moisture wicking
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Reviewed in the United States on April 25, 2026
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Theresa
Draper, US
★★★★★ 4
No show but stays on
Size: Medium, Color: (014) Halo Gray / Halo Gray / Castlerock
I wear these socks daily. They truly don’t show with my workout shoes or with hey dudes. But the best thing about them is that they actually stay on your foot. I work out hard and I don’t ever have to pull them up. I do wish they were just a little bit thicker than they are, but they are definitely a product I will buy again.
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Reviewed in the United States on May 22, 2026

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