Good (relatively cheap) DIY Bluetooth speaker?

hello,

coming from a studio monitor setup with treated room/eq correction, i wanna build a fairly high end portable speaker for good quality "background" music

im thinking right now about a raspberry pi + amp hat + 1 or 2 tang band broadband drivers

but i have a few question...
1. what options do i have if i wanna integrate a dsp/eq in the chain? raspberry pi would be a good bet i guess
2. if the driver are pretty close to eachother in one box, is there a benefit going stereo instead of mono? (the only real benefit i see here is more headroom for dsp/eq)
3. i dont really know how i would power a raspberry + amp hat combination, wired is no problem i guess but battery powered?
4. what you think about the idea? i mainly would listen to it in my room, so i guess i could also build a proper stereo setup for my desk with small drivers but i kinda like the idea of a good quality bluetooth speaker (bluetooth wouldnt be the only protocol tho but a additional option, directly streaming from the pi is probably a better way)
or is this idea crap and i should just buy a ready made bluetooth speaker? im willing to pay around 300-400€
 
5"-6" 1/2 ported woofer in the center, 2"-3" full range on the sides in closed chambers playin anywhere from about 200Hz and up, 2.1 amp with bt, 6s lipo pack and the rest of the hardware, packed in a sort of a briefcase shape.
Screenshot_2023-05-24-21-27-19-698_com.speakerbox.app.jpg

Screenshot_2023-05-24-21-26-53-369_com.speakerbox.app.jpg
 
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Only if you have nothing better to do. ;)
i dont count "work hours" to be honest, if its in the end a better value purely because of parts i would be happy

5"-6" 1/2 ported woofer in the center, 2"-3" full range on the sides in closed chambers playin anywhere from about 200Hz and up, 2.1 amp with bt, 6s lipo pack and the rest of the hardware, packed in a sort of a briefcase shape.
sounds like a good plan, tho to be honest i wanted to leave out a subwoofer

i looked a bit for chassis and this is i think a good one:
https://oaudio.de/Nach-Hersteller/Tang-Band/TangBand-W5-2106html
pretty sure i can get 50hz out of it with a little eq
little bass boost, little treble reduction and a subsonic filter should be enough right?

since its a bit more expensive chassi (is this even a good pick for a broad treble sweet spot?)

is mono vs stereo noticable? but im also wondering when we route stereo to mono if phase stuff/effects can mess things up with only one speaker outputing the combined output of 2 channels

Edit: or maybe 1 or 2 of these? https://oaudio.de/Lautsprecher-Selb...itbandlautsprecher-8-cm/Tang-Band-W3-2141html
 
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I'm using it with Xperia8, AIYIMA B2D1957 (Bluetooth amp) and PEERLESS PLS-830985 (2.5" fullrange).
It costs about 60€ for an amplifier and pair speakers.
It produces enough bass for my needs, but you can boost it with the graphic equalizer on your phone if you think it lacks bass.

 

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I'm using it with Xperia8, AIYIMA B2D1957 (Bluetooth amp) and PEERLESS PLS-830985 (2.5" fullrange).
It costs about 60€ for an amplifier and pair speakers.
It produces enough bass for my needs, but you can boost it with the graphic equalizer on your phone if you think it lacks bass.
i was watching some comparision videos just like yours the last days and yours compared to the rest i watched i must say, your setup sounds quite nice for such little speakers :)

1. i kinda wanna keep the project quite simpel so i will probably leave out the sub, i just dont feel really comfortable implementing one and it makes things more complicated
2. also i kinda would like to avoid bassreflex, i rather use dsp to get some more bass in exchange of lower max volume, but i will also probably choose a 4 or 5" tang band
3. where im still unsure is mono vs stereo in one case
4. i have to look for some (good) amp hats for the raspberry pi, im still not sure whats out there and what options i have, powering the stack might be easy or not so with battery
 
Because there are good and decent priced amplifiers out there, which come with DSP and also multiple channels. These should be more simple to run relieable on battery.
i saw amp boards supporting sigmastudio dsp, but honestly i dont wanna dive into yet another program
atleast for me using linux itself for the digital part seems more convenient

Is DSP the only reason to use a computer for the headunit?
1. i like linux EQ`s which im familiar with, specially the easyeffects eq sounds better than other ones because you can set it not just as IIR but also as FIR/FFT/SPM (which each gets better then the before pretty much)
2. i kinda like the idea of using it as "radio" without necessarly depending on a source which also allows to use proper lossless digital connection without relying on bluetooth, i think that right now the biggest point for me for a raspberry pi
 
For bluetooth speakers (a boombox basicly) I would go mono, stereo won't work right if the drivers are to close to each other. If you want to get bass out of it, you need a driver that can deliver bass (enough xmax). Many Mark Audio drivers can do that, and some from Tangband (W5-1880 would be good, but is very expensive). Smaller drivers won't do that, and sealed will be hard to get that low. Even with eq, the driver needs to have enough xmax and cone surface to get low and a TL will be difficult because the box will become large and less portable.

I would probally use a Mark Audio 10.3 in a 16L (internal size) ported, with slot ports on each side of the driver, and the amp/dsp on top or on the back. That gives you a response below 50Hz when tuned right, and can go fairly loud (important factor). Protect the driver with a speaker cloth grill if you go outside, as the driver don't like direct sunlight on it's cone, and also as protection. You can use the Rasberry PI as dsp and receiver of singals, and an Icepower module to power it. I would not use the Hifiberry amp modules as they are crap. Idem with most of the cheap chines IC amps (Sure, Wondon, Arylic, ...) that are arround. They don't deliver the power promised and are high distortion when giving only a few watt. There may be some good TPA3116 based boards arround that also can do that, but i'm not a specialist, and many are not good. So watch out and read enough about it before you buy.

The CHN110 or even the CHP90 can be a good alternative that is cheaper to buy, but for both the cabinet needs to be about 20-25L internal space and the port will be harder to intergrate as they are longer.
 
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For bluetooth speakers (a boombox basicly) I would go mono, stereo won't work right if the drivers are to close to each other.
yes i have the same thinking, but im a bit worried about phase stuff messing things up if i route left and right channel into one mono channel


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first time i read markaudio, are these good drivers?

doesnt sound a chassi with less xmax more precise? im specially worried with broadband speakers if 40hz and 12khz are playing at the same time with huge xmax
 
What's your SPL expectation? W5-2143 will hit xmax at just above 1W in a 19l closed cabinet at 50Hz. There's no headroom left for eq.

I'd suggest you simulate your prefered driver in WinISD, Vituixcad or Hornresp or similar free software to see what you get.

Screenshot_2023-05-27-16-10-37-700-edit_com.android.chrome.jpg


If you want low end extension you're gonna have to use a bigger driver, bass reflex or passive radiator.
 
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What's your SPL expectation?
well i kinda dont wanna play at full blast so 90db at 1m is pretty plenty imo

my real goal here is a "high end" speaker for background(!) listening, if i wanna play at full blast i can do so with my normal setup
and even with my normal setup i just listen around 70-80db if i listen loud (my speakers can do 108db x) in the case you wanna go deaf...)

what im unsure off is distance... if the box plays at the other end of the room 90db at 1m goes down to 84db at 2m and 78db at 4m if i remember right, i think it should be fine but... hmm

i didnt expected 1w to already hit xmax tho
but in any case, im kinda willing to trade max spl into lower bass (my real goal here is 40hz but i dont mind a "little" rolloff )
 
yes i have the same thinking, but im a bit worried about phase stuff messing things up if i route left and right channel into one mono channel


--

first time i read markaudio, are these good drivers?

doesnt sound a chassi with less xmax more precise? im specially worried with broadband speakers if 40hz and 12khz are playing at the same time with huge xmax
You need do to it right, with a schematic like here:

1685196504172.png

Or even better, use the dsp to go to mono. Most can do that very easely and without phase issues.

And Mark Audio drivers are among the best arround. They are very high engineerd, and more neutral sounding than almost all fullrange drivers, and with decent xmax (more than most midbass drivers of that size). They get away with that high xmax due to a very stiff cone (mostly made of a very fine copper alloy) and special spider that helps with the control of the cone. And due to their shallow cones, they are very good in dispertion of the high frequencies.
They are based on the tech of Ted Jordan (Jordan speakers) where the designer of Mark Audio worked in the past but surpassed the Jordan drivers. If you never heared about them, you should read up on fullrange drivers, they are very high rated. If you know modern Jordan or Scanspeak/EAD fullrange drivers, those are based on the same tech (but less advanced).

TB is that not so much, and with the limited xmax not very good in giving real bass. Certainly in a small reflex they (except that very expensive one) won't do what you want as the paper cone and limited xmax will severly limit the bass response. In a large TL or Horn speaker this is less an issue.
 
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Why not build a mono 2-way? Single stereo amp with DSP can do that easily. A woofer and fullrange driver. Relieve the fullranger of the LF duty so it can play loud and clean the rest of it and use the woofer up to baffle step. A ported / pr woofer would probably take up less than 10 liter volume and the fullrange driver probably around 3 liters so the box would be about 15 liter gross. Tangband W5-1138SMF would do a good job for the low end and if you want a cleaner sound get a slightly bigger woofer.

Screenshot_2023-05-27-16-41-10-389-edit_com.speakerbox.app.jpg


Screenshot_2023-05-27-16-43-13-478_com.speakerbox.app.jpg


Although that W5 is fugly, it does the job pretty well.
 
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Why not build a mono 2-way? Single stereo amp with DSP can do that easily. A woofer and fullrange driver. Relieve the fullranger of the LF duty so it can play loud and clean the rest of it and use the woofer up to baffle step. A ported / pr woofer would probably take up less than 10 liter volume and the fullrange driver probably around 3 liters so the box would be about 15 liter gross. Tangband W5-1138SMF would do a good job for the low end and if you want a cleaner sound get a slightly bigger woofer.
oh, i really like this idea! i havent thought about this
i was just thinking about one channel being unused if i buy a stereo amp (or a dac..)

with raspberry pi and camilladsp this could be easly done

i think this would be one step closer to high end with a seperate woofer doing like 40-100 or 200hz, this would also allow for a smaller 3" fullrange speaker which are mostly considered better for treble