Which power amplification for different powered speakers ?

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Hello, I have one 50W subwoofer and two 20W woofer and tweeter and I want to power them by the same amplifier by adding a crossover.

In an other post someone tell me that I had to amplifie the signal until 50W and split it by a 3 way crossover because the subwoofer receive almost all of the power. But when I do this, in some music, acute sound bad at high sound level.

I wondering if it is not because of the fact I amplifie in 50W but the tweeter are 20W. Is that possible ?
If so can you tell me what can I do to amplifie all these divices perfectly by using only a one 50W channel ?

Thanks for helping me and excuse me for my bad english (if it is) because I am french
 
Hi! You are doing well with the English - my French is very bad - c'est la vie!

The tweeter will only see around 20% of the 50W input - that is 10W.

A correctly designed crossover will make sure that each of your drivers (subwoofer, twin woofers and tweeter) will get their proper share of the total amplifier power.
 
What kind of crossover are you using? Schematics and component values, please.
20 W tweeter is more than enough for a 50 W amplifier, it is not a problem.
Bad sound at high sound level might be amplifier clipping (you are reaching amplifier limits), or may be an inadequate crossover.
 
thanks for your answers, I use this crossover witch I choose because of its frequences, indeed, frequences of the crossover are good for my speakers so I don't think I choose the wrong one:

1 pc Haut Parleur Frequence Diviseur 3 Voies Haut parleurs Audio De Voiture trois Crossover Diviseur 260 W Treble Mediant Basse Crossover Filtre dans Amplificateur de Electronique sur AliExpress.com | Alibaba Group

with this amp:
DC12 24V Mono canal 50 W TDA7492MV classe D amplificateur Numerique conseil dans Amplificateur de Electronique sur AliExpress.com | Alibaba Group

But the fact is that in some musics it sound really good but in few others it is bad at the same sound level.

If the tweeter go with 10W, should I take a more powerfull amp ? like 100W to have 20W for my tweeter
 
The class D amp which you are using is not very expensive and is likely to produce distortion when turned up loud.

A higher quality amplifier would work better - I would use a class A/B amp.

Also, the amp's power supply has to be strong - which supply are you using?

The crossover is probably OK, but won't have been designed to give the best results with the drivers you are using.

Give details of your drivers - someone may suggest a better crossover design.

However, I would want to improve the amp before looking at the crossover.
 
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It sound good for most of the musics, I noticed that the acute are shrill in this song : "stick figure fire on the horizon" around 1:09 min when the singer is singing. I agree it should be the amp but if I change it, do I have to take a more powerfull one ? and I have not too much money so is it possible to find a A/B amp around 20$ ?

My speakers are:
tweeter: Visaton TW 6 NG, 8 ohm (Tweeter a cone Visaton TW 6 NG, 8 ohm, 60 x 60 mm)
woofer: FaitalPRO 3FE22, 8 ohm (Haut-parleur large-bande FaitalPRO 3FE22, 8 ohm, 3 pouce)
subwoofer: Monacor SPH-210, 8 ohm (Haut-parleur Monacor SPH-210, 8 ohm, 210 mm)
 
my power supply is a home made 12.6V battery made with 9 18650 lithium battery. Can the power supply affect the sound ?

It certainly can!

The best supply voltage for your amp is 25Vdc. Do not use greater or smaller than that.

I would not use lithium cells - two high capacity Yuasa 12V sealed lead acid batteries, connected in series,would be better.

Besides, 9 x 3.7V lithium batteries, if connected in series, would give 33V!

The amp won't like that at all!

NOTE: A 18650 lithium cell is 3.7V NOT 1.4V!
 
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No I connected 3 pack of 3 cells in serie, in parallele to imrouve the duration. The fact is that when they are fully charged, 18650 battery is to 4.2V so 7x4.2=29.4 and it is too much too no ?
And can you tell me how do you know that 25V is the best because it is wrote that it can be connected in a range of 12~24V
 
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Can you tell me if it is possible to have a class A/B amp for around 20$ and if I can take a 100W one, indeed my current amp as a maximum of 50W witch is the RMS of my subwoofer so if I take a 100W one (witch is the maximum of my sub) it will fit perfecly with my sub and the 20% witch get the tweeter fit also good with the 20W of my tweeter.
thanks for your usefull answers :)
 
There is cause for confusion - you said 12.6V in post #8!

29.4V is the emf (E) of the battery. The voltage (V) across the terminals of the battery will fall when the amplifier draws current from the battery. This is due to voltage being 'lost' in driving current through the internal resistance of the battery.

When a loud passage of music occurs, the voltage (V) may fall so far that the amplifier distorts.

This would be cured by a stronger power supply.

I would think about this before giving up on your present amplifier.

P.S. I got the supply voltage information from the amp's data sheet which is available on-line as a pdf.
 
Can you tell me if it is possible to have a class A/B amp for around 20$ and if I can take a 100W one?

Perhaps something like this?

Search: LM3886 100W Mono Class AB audio power amplifier board.

Note: I have no experience of these amp boards and do not know how well they perform!
 

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And can you tell me how do you know that 25V is the best because it is wrote that it can be connected in a range of 12~24V

From Class D amp Data Sheet:

Power output is 40W (at 10% distortion) with 25Vdc, but only 15W with 12Vdc.

A new amp will still require a strong power supply! You need to consider that before buying a new amp.
 
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Do I really have to get around 30V for these kind of amp ? because it will decrease my battery life to put them in series instead of parallele.

Your class D amp needs a 24/25V power supply. It should be capable of providing a current of about 2.5A at its rated voltage.

Two high capacity 12V sealed lead acid batteries in series will give the required voltage, as well as being able to supply the large current without dropping their voltage too much.

Of course, they cost money and you would also need to buy a charger for them.

The alternative is to buy a suitable mains operated supply.
 
Yes think I will stay on litthium because I recycled them so it cost me nothink and I don't now how to deal with acid battery. If I buy a class D 100W mono amplifier it should be better no ? I mean, if the distotion come at some sound level for a 50W amp, for the same sond level it souldn't be distorted with a 100W one right ?
I say that because (tell me if I am wrong) a class D amp is better for the battery life than others, so if I havn't any issue with a class D amp it will be better.
 
You have been powering your class D amp with 12Vdc.

I hope you now understand that it is best powered with 24Vdc.

24Vdc will get you 30W at 1% distortion and 40W at 10% distortion.

But the power supply must be able to supply a large current (at least 2A).

Your lithium batteries may not be suitable for this purpose.
 
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