2.1 amp recommendation

[bcodemz]

I'd like a recommendation on a 2.1 amp. It should have around 25 watts for the 2 channels and 50 watts for the sub channel. The amp should be a finished board, AND take 3 inputs because this is for a 3 way speaker.

So far I've found these

Yuan-Jing LM1875 2.1 Channel Amplifier Board 2 x 25W + 1 x 50W

Yuan-Jing TDA7850 4 x 50W Audio Amplifier Board

Anything else that I should look at?

Thanks!

 

[AndrewT]

What are the sensitivities of your satellites and bass only speakers?
If they are the same, then the POWER that each NEED should be the same.
If the satellites are 3dB more sensitive, then the bass only needs double the POWER to achieve the same SPL.
If 6dB more sensitive, then 4times the POWER.
If 9dB more sensitive, then 8times the POWER.
If you have two satellites and one Bass only speaker and they are all about the same distance from the listener, you will probably have to double the Bass POWER again.

Do you see a problem arising?
The bass only is going to get overloaded as the required SPL rises (as you turn the volume up a bit).

Buy a sensitive Bass only driver that matches fairly closely the sensitivity of the satellites, within 1dB or 2dB.
And/or buy three Bass only speakers and spread them around the room (as advocated by more than a few on this Forum).

Once you have some targets, ask the amp question again.

 

[bcodemz]

The speaker design is "unique", in that it is a very compromised design in order to get reasonable bass. The tweeter and midrange will be capable of much higher SPL than the woofer. There will be a DSP limiter in place for the woofer so it doesn't overtly distort or kill itself when the volume is high. Therefore, the goal is to just supply enough power or more to the drivers so the amp isn't contributing distortion in the operating range of the drivers.

Here are the sensitivities for reference:

Tweeter: 91dB/2.83V
Midrange: 86dB/2.83V
Woofer: 82.6dB 1W/1m

 

[Arty]

Yuan-Jing LM1875 2.1 Channel Amplifier Board 2 x 25W + 1 x 50W

thatone will do what you need.

 

[bcodemz]

Yuan-Jing LM1875 2.1 Channel Amplifier Board 2 x 25W + 1 x 50W

thatone will do what you need.

How would that compare to this amp? It has double the power for the same price.

12V 50WX2 100W TPA3116D2 2 1 HiFi Digital Subwoofer Amplifier Verst Board | eBay

Also, are these amps capable of taking 3 inputs? An amp that only takes stereo and uses an internal crossover for the subwoofer channel is not useful for me.

 

[Arty]

thatone is class D.
from quality view of point class AB might be better, but both are good amplifiers.

both of them take a stereo input, and do 3rd channel with adding the stereo input.
You might want to look for monoblocks if you want more inputs.