Passive Subwoofer with Leppy 2020A+ Amp

[NoodleGod]

I'm getting the Lepy LP-2020A and would like to connect my passive 10" sub to it. The sub has L and R inputs and Outputs on it but I don't know if there is a low pass filter built in or not. The amp just had the L and R out and no pre-amp or sub out. If i connect the L and R outputs of the amp directly to the sub will the sub and it does't have a low pass filter built in, will it be bad having all that high frequency sound passing through it? 

 

I'm including pictures so if you know weather or not these can be connected safely or not and how please let me know!

[The Flying Sloth]

First of all, there are a lot of amps I would suggest over that one but to make things very blunt, your subwoofer will need a crossover to ensure it's only getting a bass signal and isn't trying to produce the whole spectrum. This amp can't do that and I'd suggest you don't try and use a single board 2.1 system either since clipping class D amps can send DC voltage to a speaker and fry it. If you want to run a subwoofer get a proper amplifier.

[Anoldt]

That amp you got there will not serve any purpose in enjoying audio.

I am also not sure if that sub has a crossover in it. You can wire it directly to the stereo out from the amp and it gives the input signal straight to the satellites. 

I wouldn't also recommend a subwoofer system for your desk. If you listen to music often, get a smaller PROPER class D amp, or a standard A/B amplifier.

Combine that with a (used?) pair of decent bookshelf speakers and you're good to go. 

 

If you really wanna use it though, you can get an active amplifier board for installation into the sub-case. This is away from cheap and brings a bit of work with it, but provides the best result. They bring their crossover with them.

Something like this: https://de.aliexpress.com/item/32995722866.html

[NoodleGod]

Well ponchato says different about that amp and here's a link. Apparently it's actually pretty good for a beginner like me. And I just have that sub laying around and was curious if it would work but you guys aren't even sure if it has corssover or not so still a mystery. I will probably go with the same powered sub featured in the video I linked but I'll try the sub I have too unless someone can guarantee it won't work.

 

 

[NoodleGod]

18 hours ago, The Flying Sloth said:

First of all, there are a lot of amps I would suggest over that one but to make things very blunt, your subwoofer will need a crossover to ensure it's only getting a bass signal and isn't trying to produce the whole spectrum. This amp can't do that and I'd suggest you don't try and use a single board 2.1 system either since clipping class D amps can send DC voltage to a speaker and fry it. If you want to run a subwoofer get a proper amplifier.

Not sure what you mean by:

" I'd suggest you don't try and use a single board 2.1 system either since clipping class D amps can send DC voltage to a speaker and fry it."

 

and I'm no audiophile I just want to use the speakers I have with my computer. I don't need to use the sub but I have it and am not using it so it would be cool if I could. Also you say you know for sure ithe sub needs a crossover? Because many places say this model has it built in and that's why it has outputs. 

[NoodleGod]

8 hours ago, Anoldt said:

That amp you got there will not serve any purpose in enjoying audio.

I am also not sure if that sub has a crossover in it. You can wire it directly to the stereo out from the amp and it gives the input signal straight to the satellites. 

I wouldn't also recommend a subwoofer system for your desk. If you listen to music often, get a smaller PROPER class D amp, or a standard A/B amplifier.

Combine that with a (used?) pair of decent bookshelf speakers and you're good to go. 

 

If you really wanna use it though, you can get an active amplifier board for installation into the sub-case. This is away from cheap and brings a bit of work with it, but provides the best result. They bring their crossover with them.

Something like this: https://de.aliexpress.com/item/32995722866.html

I'm not looking for fancy sound, just trying to hook up speakers I already own to my PC for as cheap as possible. I'm not using the speakers or sub and thought it would be cool to get them working. If I can only hook up speakers to the amp I'm getting that's cool, just wondering why most places I look say this model sub has built in cross over and some say passive subs always need a seperate crossover. 

[ShearMe]

 

6 hours ago, NoodleGod said:

I'm not looking for fancy sound, just trying to hook up speakers I already own to my PC for as cheap as possible. I'm not using the speakers or sub and thought it would be cool to get them working. If I can only hook up speakers to the amp I'm getting that's cool, just wondering why most places I look say this model sub has built in cross over and some say passive subs always need a seperate crossover. 

I would guess that there is a crossover. Best way to find out is to take a screw driver to it, and pop it open. If there's any electronic components other than wires going straight to the subwoofer, it has a crossover.

 

There's nothing wrong with the Lepai/Lepy stereo amps.... as long as you set your expectations right. These are pretty much the cheapest amps on the market. Don't over drive them and they will serve you well.

[NoodleGod]

38 minutes ago, ShearMe said:

 

I would guess that there is a crossover. Best way to find out is to take a screw driver to it, and pop it open. If there's any electronic components other than wires going straight to the subwoofer, it has a crossover.

 

There's nothing wrong with the Lepai/Lepy stereo amps.... as long as you set your expectations right. These are pretty much the cheapest amps on the market. Don't over drive them and they will serve you well.

Thanks!

 

I just set it up and i can hear high frequencies coming through but it is very clear and of course, bassy.

 

I also took it apart and attached pictures. Is this what a crossover setup looks like? 

[NoodleGod]

Just an update even tho no one cares,

 

The sub works perfectly with my Lepy 2020A and my Klipsch 14-m speakers and the sound is amazing. I'm gonna upgrade the amp and get a good DAC in the future but for now I am pleased. 

[The Flying Sloth]

Yeah, that's a passive crossover, if it works and you enjoy it that's all that matters.