Help needed for 2.1 Bluetooth speaker system

[arjanmaas91]

Hello everyone,

Let me start by saying that I’m quite a novice when it comes to audio stuff / speaker design. I’m going to build a 2.1 Bluetooth speaker. I want a relatively small speaker but aim for pretty good sound especially for the size of the speaker. So far I have selected a few components but I need advice. Here is the list of the parts so far:

Amplifier board (plan is to not run it at full power but provide it with 15 or 19V to reduce overall output power) It is hard to find an amp with 2 x 25 and 1x 50 but there are quite some that are 2 x 15W and 1 x 25W for the sub:
Aiyima 2017 New TPA3116 Subwoofer Amplifier Board 2.1 Channel High Power Bluetooth Audio Amplifier Board DC12V 24V 2*50W+100W-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

2 x Full range drivers:
Dayton Audio ND65-4 2-1/2" Aluminum Cone Full-Range Neo Driver 4 Ohm

1 x Subwoofer:
Tang Band W3-2088S0F 3.5" RBM Micro Subwoofer 4 Ohm

Maybe 2x tweeter:
Dayton Audio AMT Mini-8 Air Motion Transformer Tweeter 8 Ohm

So here is where I’m lost. I do not know how to select the proper drivers. I’m afraid that the full range speakers will not shine in the highs. Therefore, maybe adding a tweeter can be a good thing. Maybe it is even better to forget about the full range drivers and go for mid woofer + tweeter. If I do so, the amp only has 3 channels. Left, right and sub channel. So, I need to make a 2-Way setup for the left and right channel. I do not know how to match power / ohms and the amplifier together. I do not know how powerful the tweeter should be or shouldn’t. Also, I’m not sure what crossover to get? I think I need to get a high pass filter and I think I can figure out how to wire the speakers and high pass, but not sure what the impact would be in terms of speaker driver selection.

Can someone please help me select or at least point me in the right direction when it comes to amp selection and driver selection taking into account a 2.1 system with 1 sub and 2 x 2 way speaker?

I’m desperate

Thanks for any help.

 

[Lojzek]

I'd start first by selecting a wide band unit, like yours, and give it first a shot without tweeter and woofer, simulate a vented design if possible without a passive radiator, only longish vent. Adding tweeter is possible with a passive crossover, a solid 1" dome should be a better option. This particular phase is not any easy one for a newbie. Subwoofer that you have on your to shop list is solidly built unit that comes with a price of low sensitivity so if you plan to employ one, the amp may or may not suffice to drive it loud enough to meet the wide band unit. It is yet to be determined and I have never come across one to do the testing.

This kit appears like a solid product.
60 Watt Powered Bluetooth Speaker Package with 3" Full-Range Drivers

 

[arjanmaas91]

Hey Lojzek,

Thanks for the advice. To give some background info, this is going to be the second speaker that I'm going to build. First speaker was with 2 full range drivers and some passive radiators. I felt like the full range drivers were lacking in the highs. That is why I want to add tweeters to this new project. The sub woofer I selected indeed has a low sensitivity.

Question:
The low sensitivity of the sub woofer, is that a problem? I mean it adds bass to the overall sound, yes indeed at a lower volume but it still adds to the overall sound. A speaker system without the added bass would still be worse right?

Thanks again

 

[Lojzek]

Without getting too much philosophical, I guess you are right. You never know with these cheap amps what you're going to get for your money. I am planning to build a boom box or a sound bar or whatever you want to call it, 2 way reflex loaded with a hump in midbass region and a 60W ab class, high quality discretely built amp, all in one enclosure, post #2.
http://www.diyaudio.com/forums/multi-way/320094-boombox-subwoofer-addon.html#post5371861