# I want to build a bluetooth boombox - where do I start?



## CoastieRon (Aug 28, 2016)

This website hasn't failed me yet so here's the newest thing- I want to build a Bluetooth boombox with leftover speaker drivers from audio builds. I have the following speakers:

1. 2 sets of KOVE KX 3.2 bi-ampable coaxial speakers

2. 1 set of PPI Power 6.5 drivers, 1 set of AMT tweets and a set of 3-way passive crossovers from a P65c3 component set

3. 1 set of Morel Tempo Ultra tweeters and a set of Tempo Ultra passive crossovers

4. 1 set of Morel Tempo Ultra Integra 602 coaxial speakers

5. 1 set of CDT 3-way passive adjustable crossovers.

I want the speaker to be "semi portable" - doesn't need to be battery powered, as it will probably stay in my garage, but it does need to be bluetooth. It also needs to power the speakers that I choose out of this mess of leftovers for the first box.

So my questions:

1. How big of a box do I need if I want to add a subwoofer driver (I'm thinking a small inexpensive one to add to the mix, but I think the PPIs would get low enough for my needs). Airspace wise.

2. What other miscellaneous "stuff" would I need to make this happen?

Thanks!























Sent from my 1+7P using Tapatalk


----------



## Isaradia (Apr 14, 2020)

I think "how loud" is a question that needs to be answered. A headphone amp would work, but I highly doubt it would get loud enough to make you happy. As far as airspace goes, depends on the drivers used, do you have a modeling software that you are semi-competent in? As far as which drivers, look up the specs on all of them and see which combinations will work well together from a sensitivity and frequency range stand point, and if you still have multiple feasible options, move on to personal preference and optimal enclosure size (from aforementioned modeling) to help make the final decision. As far as making the enclosure, a hifi board, and probably other users here will be more helpful, but I'd suggest building it out of mdf, to specs given by modeling (it seems like this is an important step), lightly loading with polyfill or the like, and if you do use a sub, brace that section of the enclosure as well as 45*ing the edges. The tweeter and mid can use the same airspace if crossing the mid high enough, but I'd separate them if letting the mid dig in lieu of a sub, again, this isn't my strong suit, so if someone knows better, listen to them. If you don't use a headphone amp (you won't), you should get a modern class d high efficiency micro amp and feed it signal from a bt module like a wirez btr-m, or for more sound quality, a hifi bt receiver or a headphone amp, this time heading into the micro amp. you'll also need an inverter..... yeah you should probably disregard most of that and use a home audio amp with bt and a wall plug, I just don't know anything about that market. Use a phone eq app for fine (rough) tuning while streaming so you don't have to buy a dsp, since I'm assuming you aren't trying to spend a ton, which is why I keep listing cheap components.


----------



## Isaradia (Apr 14, 2020)

Oh, and obviously use the crossovers that work with you speaker choice, probably the adjustable ones. If they don't high pass your lowest range speaker, make sure (via.... MODELING!!!) that they won't over excur, which can be controlled by power, enclosure, or both, also the amp SHOULD have a high pass, so you likely won't have to consider this, but just in case... also you can use horn loading on the tweeter, and under-sizing on the low range enclosure to increase tweeter output and decrease bass output, but that's most likely going to be the opposite of what you want


----------



## CoastieRon (Aug 28, 2016)

I think for my first one (because I know building a second one is going to happen) I'm going to use the Morel Coaxials with a cheap sub speaker.


----------



## CoastieRon (Aug 28, 2016)

CoastieRon said:


> I think for my first one (because I know building a second one is going to happen) I'm going to use the Morel Coaxials with a cheap sub speaker.


Strike that, I'm going to use the PPI stuff.


----------



## glockcoma (Dec 22, 2015)

For the Bluetooth amp I would recommend TPS3116D2 board. It’s rated 50 x 2 and 100w on the sub channel. 
You can feed it with anywhere from 12-24 vdc and it will be happy. More voltage, more watts 

I’ve used this in several projects with excellent results. 
Not sure if we can link sites here but parts express is an great place to get it. 
I’ve ordered the board from amazon, it looks the same but uses lower quality components and you can definitely tell the difference.


----------



## CoastieRon (Aug 28, 2016)

Where I'm at right now. Waiting for the amp.
















Sent from my 1+7P using Tapatalk


----------



## lingling1337 (Oct 14, 2019)

Man you just get straight to work! Good stuff! P-E and Amazon both have cheap bluetooth 2.0 amplifiers, and even mono or 2.1 amplifiers. They will run on a regular laptop power supply. The cheap amazon ones are bare boards, the Dayton ones are actual plates with controls you can mount into the face of your box.


----------



## CoastieRon (Aug 28, 2016)

lingling1337 said:


> Man you just get straight to work! Good stuff! P-E and Amazon both have cheap bluetooth 2.0 amplifiers, and even mono or 2.1 amplifiers. They will run on a regular laptop power supply. The cheap amazon ones are bare boards, the Dayton ones are actual plates with controls you can mount into the face of your box.


Yeah, I went right to it. I live doing new stuff. I got a Dayton 2x50 with the plate and all that. It gets here tomorrow.

Thanks!

Sent from my 1+7P using Tapatalk


----------



## CoastieRon (Aug 28, 2016)

My speakers' polarity were incorrect so I fixed that. Sounds great!

Sent from my 1+7P using Tapatalk


----------

