New speaker sound very soft

I just installed two “new” speakers from iFixit in my MacBook Pro late 2013. They installed without any problem, but when at maximum sound they are not very loud and are about 1/2 the volume they should be. At half volume I can’t even hear sound, at 3/4 it is just recognizable.(These speakers are considered used when I purchased them because of the age of my computer.) Is it likely that the speakers are just not working or that I have something set incorrectly? I have gone into the sound settings and moved it left to right and both seem to be the same volume. What should I try next?