Low volume and thin sound when recording...

[Coffee]

Hi!
When I record something via recorder of the keyboard or when I connect PX-5S to my PC with 3.5 mm to 3.5mm cable via headphones output and record the sound with Audacity, i got significantly lower volume and thinner sounding. How can I solve this problem?
I don't have audio interface or external sound card. So, my onboard sound solution of motherboard is not so great which i can accept. But why keyboard itself also records so badly ? 
How do you record the sound of PX-5S ?

 

(Additional note: When i connect to the PC as i say, the sound is great and full, but i can't say the same thing for recording unfortunately. )
 

[Brad Saucier]

Since you have Audacity, I recommend simply copy the recorded wav file onto your computer then use the Audacity normalize effect.  

[Coffee]

On 13.10.2017 at 9:24 PM, BradMZ said:

Since you have Audacity, I recommend simply copy the recorded wav file onto your computer then use the Audacity normalize effect.  

I'll try that ASAP. Thank you.

[Coffee]

On 13.10.2017 at 9:24 PM, BradMZ said:

Since you have Audacity, I recommend simply copy the recorded wav file onto your computer then use the Audacity normalize effect.  

I tried the effect today. I got noticeably better sound.

[Coffee]

On 13.10.2017 at 9:24 PM, Brad Saucier said:

Since you have Audacity, I recommend simply copy the recorded wav file onto your computer then use the Audacity normalize effect.  

Using the amplifier effect also helps a lot. Just pay attention to distortion problem and don't over-use amplifier effect.