Hello everyone, forgive me if this has been asked before, or if i am in the wrong thread.
I've gotten my hands on some fantastic furniture, and to make it even better i decided to build some custom speaker units for it, along with a pc case.
Now, i am completely dumb when it comes to audio, and also half deaf to one ear, so it is more about looks than amazing sound quality. I spent days looking around for woofer/tweeter units, then i realized that i have an old 5.1 sound system i could use with a dead dvd player. Since it has to be simetrical, i will order another 5.1 speaker set that is the exact same as the one i own for like 25$.
Now, the plan is to use 1 tweeter and 1 woofer / box and make a stereo setup.
Woofer is 30w 4 ohm, tweeter is 15w 6 ohm, and i plan to use an audio crossover i will order later on.
My questions are fairly simple, despite the lengthy talk.
-Impedance has to be 4+6=10 or 6 for the amp.
-Wattage of the amp has to be 15 for the lowest speaker, 45 as combined, or 30w for the highest part?
-Crossover question is same as wattage 15,30,45, or i can just get whatever that is above these?
-Does the size of the woofer unit matter?
This is the amp i would like to use, unless somebody has something similar in mind, price wise. (this is an aliexpress link) 50WX2 Bluetooth 5.0 Power Amplifier Board TPA3116 Receiver Stereo Home Car Audio Amp USB U disK TF Music Card Player|Amplifier| - AliExpress
Unfortunately Ebay is not an option for me because of my country of origin.
Thank you all in advance.
I've gotten my hands on some fantastic furniture, and to make it even better i decided to build some custom speaker units for it, along with a pc case.
Now, i am completely dumb when it comes to audio, and also half deaf to one ear, so it is more about looks than amazing sound quality. I spent days looking around for woofer/tweeter units, then i realized that i have an old 5.1 sound system i could use with a dead dvd player. Since it has to be simetrical, i will order another 5.1 speaker set that is the exact same as the one i own for like 25$.
Now, the plan is to use 1 tweeter and 1 woofer / box and make a stereo setup.
Woofer is 30w 4 ohm, tweeter is 15w 6 ohm, and i plan to use an audio crossover i will order later on.
My questions are fairly simple, despite the lengthy talk.
-Impedance has to be 4+6=10 or 6 for the amp.
-Wattage of the amp has to be 15 for the lowest speaker, 45 as combined, or 30w for the highest part?
-Crossover question is same as wattage 15,30,45, or i can just get whatever that is above these?
-Does the size of the woofer unit matter?
This is the amp i would like to use, unless somebody has something similar in mind, price wise. (this is an aliexpress link) 50WX2 Bluetooth 5.0 Power Amplifier Board TPA3116 Receiver Stereo Home Car Audio Amp USB U disK TF Music Card Player|Amplifier| - AliExpress
Unfortunately Ebay is not an option for me because of my country of origin.
Thank you all in advance.
Welcome to the forum.
Since your woofer is 4 ohm that is the main load your amp will see. It should not be a problem. If you run that little Bluetooth amp on 24V DC you might get the rated power into 4 ohms, although you'd likely never use it all.
Don't worry about matching the amplifier power rating to the speakers, it deosn't work that way. Whether or not the amp will be enough for you depends on many things, the efficiency of your speakers, the size of your room, how much EQ you use and how loud you listen. It has little to nothing to do with the speaker power rating. If you are in a normal size domestic room, the amp should be enough for normal listening.
The crossover is important, and you'll want a way to adjust the tweeter level.
Since your woofer is 4 ohm that is the main load your amp will see. It should not be a problem. If you run that little Bluetooth amp on 24V DC you might get the rated power into 4 ohms, although you'd likely never use it all.
Don't worry about matching the amplifier power rating to the speakers, it deosn't work that way. Whether or not the amp will be enough for you depends on many things, the efficiency of your speakers, the size of your room, how much EQ you use and how loud you listen. It has little to nothing to do with the speaker power rating. If you are in a normal size domestic room, the amp should be enough for normal listening.
The crossover is important, and you'll want a way to adjust the tweeter level.
Thank you.
The amp will run on 12v 5a, as that is the brick they are selling for it.
They say 30w*2 on that voltage and ampere, so it can't reach 50w*2.
As for tweeter adjustment, can i use the equalizer on my pc in the sound card software?
What do you mean by the crossover is important? Like having one, or the quality?
The amp will run on 12v 5a, as that is the brick they are selling for it.
They say 30w*2 on that voltage and ampere, so it can't reach 50w*2.
As for tweeter adjustment, can i use the equalizer on my pc in the sound card software?
What do you mean by the crossover is important? Like having one, or the quality?
12 volts isn't much of a power supply, but can do a decent job if your speakers are efficient or your room is small. Most speakers aren't very efficient.
The crossover can make or break a speaker, it's a vast and complex subject that is worth learning. So you have to start somewhere. The basic function of the crossover is of course to send the frequencies ranges where they need to go, but another import function is level control. Usually that means attenuating the tweeter so that it matches the output of the woofer. That's why a level control on the tweeter is handy.
The crossover can make or break a speaker, it's a vast and complex subject that is worth learning. So you have to start somewhere. The basic function of the crossover is of course to send the frequencies ranges where they need to go, but another import function is level control. Usually that means attenuating the tweeter so that it matches the output of the woofer. That's why a level control on the tweeter is handy.
The room is fairly small, at 3x3 meters.
I am half deaf to one ear, and can't really hear high frequency sounds.
This is the crossover i was eyeing.
74 * 60 * 28 MM 80W Speaker 2 Way Audio Frequency Divider Loudspeaker 2 Units Crossover Filters for Speakers Accessories Kits|Speakers Sets| - AliExpress
Can i use a simple potentiometer on the positive side for volume adjustment on treble?
Since the amp itself only has general volume control.
I am half deaf to one ear, and can't really hear high frequency sounds.
This is the crossover i was eyeing.
74 * 60 * 28 MM 80W Speaker 2 Way Audio Frequency Divider Loudspeaker 2 Units Crossover Filters for Speakers Accessories Kits|Speakers Sets| - AliExpress
Can i use a simple potentiometer on the positive side for volume adjustment on treble?
Since the amp itself only has general volume control.
You'll need an L-pad between the crossover and tweeter for level adjustment. It's a little more than a potentiometer, it presents an impedance to the crossover that doesn't change with the adjustment setting. That's important, because a regular potentiometer would make unwanted changes to other factors along with changes to the tweeter level.
Those crossovers are questionable, they don't give a crossover frequency in the specs. It wouldn't be an accurate number, but it's still the one spec that should not be left out.
Crossovers are not something that can be a "one size fits all" solution. That's the one part of your project that ties everything together. It *should* be designed for that woofer, that tweeter, in that enclosure shape, with that spacing between the speakers, etc. Have a look at AllenB's thread about designing crossovers for some more info about this.
But, budget and time and the interest in getting something done are all understandable issues. If you want to concede and take the pre-made "universal" crossover path, I would suggest using one with 2nd order filters, also called 12dB/octave filters. They will provide better tweeter protection and a fixed crossover frequency. And add an L-pad for adjustment.
Those crossovers are questionable, they don't give a crossover frequency in the specs. It wouldn't be an accurate number, but it's still the one spec that should not be left out.
Crossovers are not something that can be a "one size fits all" solution. That's the one part of your project that ties everything together. It *should* be designed for that woofer, that tweeter, in that enclosure shape, with that spacing between the speakers, etc. Have a look at AllenB's thread about designing crossovers for some more info about this.
But, budget and time and the interest in getting something done are all understandable issues. If you want to concede and take the pre-made "universal" crossover path, I would suggest using one with 2nd order filters, also called 12dB/octave filters. They will provide better tweeter protection and a fixed crossover frequency. And add an L-pad for adjustment.
Well. Budget is truly one thing to consider in my case.
That's why i scrap an 5.1 system for the subwoofer and the tweeters.
The other one is that, the speakers must be custom made to fit the furniture.
The fact that the amp has no way to adjust the tweeters seem to introduce a lot of problems if i understand it correctly.
Would it be better to use something like this?
2*50W+100W Bluetooth 5.0 TPA3116D2 Power Subwoofer Amplifier Board 2.1 Channel Class D TPA3116 Audio Stereo Equalizer Amp|Amplifier| - AliExpress
I'd use the left and right channel, then a pre-made crossover (I will ask around for recomendations if you are saying the one i linked isn't really good/questionable).
You are right, i don't really want to dwell too deep into the matter.
I probably build this, and another 2 for aesthetic reasons and will never touch the subject again. That's why i would like to ask you experienced people for advice. Rather than learning everything about the subject. And i am truly grateful for your answers.
That's why i scrap an 5.1 system for the subwoofer and the tweeters.
The other one is that, the speakers must be custom made to fit the furniture.
The fact that the amp has no way to adjust the tweeters seem to introduce a lot of problems if i understand it correctly.
Would it be better to use something like this?
2*50W+100W Bluetooth 5.0 TPA3116D2 Power Subwoofer Amplifier Board 2.1 Channel Class D TPA3116 Audio Stereo Equalizer Amp|Amplifier| - AliExpress
I'd use the left and right channel, then a pre-made crossover (I will ask around for recomendations if you are saying the one i linked isn't really good/questionable).
You are right, i don't really want to dwell too deep into the matter.
I probably build this, and another 2 for aesthetic reasons and will never touch the subject again. That's why i would like to ask you experienced people for advice. Rather than learning everything about the subject. And i am truly grateful for your answers.
Let's keep it very simple then.
You're initial choice of the 50Wx2 Bluetooth amplifier is fine and I would stick to it.
The basic help you need, as I see it, is how to wire the woofer and tweeter together so that the bass notes don't get to the tweeter.
If the tweeter turns out to be too loud, we can deal with that later.
A basic crossover, consisting of a single capacitor in series with the tweeter, would be enough to get the drivers working together safely.
Aa educated guess for the capacitor value would be 4.7uF and this should be a plastic film type as shown here: 4 7 fd Monacor MKP Capacitor
You would wire the woofer, capacitor and tweeter together as shown in the attachment (ignore the values shown in the diagram).
Attachments
P.S. A more tailored crossover would require knowledge of the full electrical parameters of both your woofer and your tweeter.
As these are unlikely to be forthcoming, the simple circuit above would at least provide a workable solution.
And now the thought strikes me - don't your existing speaker sets already contain the required crossover circuitry?
As these are unlikely to be forthcoming, the simple circuit above would at least provide a workable solution.
And now the thought strikes me - don't your existing speaker sets already contain the required crossover circuitry?
A 6.5" woofer - I'd be fairly confident that my simple crossover suggestion would give a reasonable result since a small woofer like this will reach high enough in frequency to blend in with the tweeter.
What about my observation that crossover components must already be present in your donor speakers?
What about my observation that crossover components must already be present in your donor speakers?
Galu is taking you down a good (simple) path for this situation.
Pictures of the parts you salvaged might be helpful. There may be level matching components already in there, too.
To add pictures to your post:
How do I attach files or post pictures in the forum?
There are no crossovers in the speakers. The dvd player which had the amp, had 6 marked output for them. Probably the fastest and best solution would vbe just to grab 2 such dvd players and another set of speaker for a second woofer. Then just build sing the woofer and for example the centr output.
Basically the dvd player, which was part of the 5.1 home theater system. Had specific connectors for each speaker, such as front left/right rear left/right. And there was nothing in their box besides the speaker itself, 2 cables to their rear, and an outside connector. Everything was regulated by the player itself which had a built in amp, and i suppose crossovers as well. Now i want to use one of these speakers and the woofer, and build them into a seperate cabinet. and i need a matching crossover, that lets me use the 15w 6ohm tweeter with the 30w 4 ohm sub. With the amp i linked earlier in mind. Sorry if i wasn't clear enough. English is not my native language, just learnt it from games.
OK, language does seem to be the problem so let's try again.
Are you wanting to make a three-way speaker by combining a tweeter, a woofer and a subwoofer in the one box?
We really need to see photographs of the items you wish to combine to make absolutely sure of your requirements.
Or, maybe I'm just being slow on the uptake!
Well, that's how it was marketed anyways. 5.1 sound system 4 corners, one center and a subwoofer. I do understand that this was a budget offering even at the time of purchase. I just consider this to be more than enough for a small room and an infant in the family in a room next to mine. So i will probably rarely use it on it's rated power anyway. The other important factor is simetry, so i want 2 identical 2 way cabinet. Because it has to match my firniture, that will house a built in pc on the middle.
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