Tiny computer speakers basing on Visaton BF37

thingiverse

Hello, Here are the computer speakers based on Visaton BF37 tiny transducers. My primary aim was to challenge the rules of physics and create as small speakers as possible delivering as much bass as possible :) And here is what I've achieved. To calculate the size of the cabinet I've used WinISD (free software for speaker cabinet calculations) feeded by the set of Thielle-Small parameters provided by Visaton. The ideal volume is 0.38 L while the length of the bass-reflex pipe is 10 cm for its internal diameter of 12 mm. Here you can listen to them: https://www.youtube.com/watch?v=MFXrRalvIiA Besides 3D printed cabinets and speakers I've used: - 21 x M2.5 screws, - 2 x audio cable with jack plugs on one side. Could be a jack-jack cable split into 2 halves. - 1 x tiny 3W 5V D-class stereo amplifier, - 1 x jack socket (to be able to detach the passive speaker). - 1 x the TP4056 li-ion charger module, where I just use the micro-USB socket. You can use the rest of the charger as well if you want to utilize the internal li-ion battery and have posibillity of charging it from USB. The cabinet dimensions are: W = 42 mm, H = 122 mm, D = 144 mm. The interior is filled with the cotton wool. If you want to optimize the volume further, you may redesign the shape of the cabinets to make them more prism-like (or rectangular, if you wish). The low frequency response is impressive for such small speakers. If WinISD doesn't cheat, the low cut-off frequency should be as low as 80 Hz (I cannot confirm it, cause I don't own apropriate microphone). I'm affraid, it seems a bit optimistic, but anyway - give them a try and you would judge yourself ;) The middle and the high pitch tones also exist and for my ear they sound fine - the bandwidth is well balanced. Additional notes: - Supports are not needed, but as the walls are tilted, you've got to take care of the proper cooling - which seems easy with PETG. You may use PLA if you wish. - The bass reflex-pipe length is 11 cm. Should be 10 cm according to WinISD calculations, however, as the STL model is a bit longer, so you can tune the low frequency response by adapting the length a bit. In case of my speakers 10 cm long pipe works well. - Take care of speakers polarity. - I forgot to design a potentiometer knob, that's why I've used a stock one. Will be updated :) - The charger costs < 0.5 $, the amplfier costs < 1 $. - The speakers are a bit more expensive around 10 $ each. - Active speaker consists of amplifier and micro-USB socket, while the passive one doesn't consist of any active components. Therefore the back covers differ for active and passive speaker. - You may use thinner print layer for nicer appearance. I was not patient enough to do so :) - Hand grinder (or at least a sharp knife) will be necessary for adapting the parts to make them fitting one to another. Particullary, it will be necessary to remove part of the screw fastening on the backside of the main part. They slightly collide with the amplifier PCB and the jack socket. However I've done it that way to avoid usage of supports. - Enclosures have to be assembled tightly, because sealing is essential for the bass. Leakages reduce low frequency response a lot. I've encountered this after first assembly, when I didn't use screws to attach loudspeakers. Tiny holes - big negative impact on the sound quality. - I plan to design the loudspeakers grills (together with potentiometer knob), so stay...tuned ;)