Whenever I connect something using 3.5mm with separate volume controls, I prefer to turn up the digital source and then use the audio device itself as the final volume control, as long as there is no static. Some cheaper speakers will buzz, so I turn my phone (or computer, etc.) down to around 70-80% volume level, but still control the final volume on the speaker.
1. see if your media source has separate volume controls, if so, turn that up, either to ~75% or 100% if there is no static
2. turn up the volume on the projector as high as it will go, if it has a volume level setting
3. control sound from your speaker. I have found that some wireless speakers have a lower level when running on battery, so maybe try plugging it into power and seeing if they will go louder?
Also, depending on your source, if it has separate audio outputs (like some game consoles or disc players do) you can maybe configure it so that it's only sending video to the projector, and sending audio out to the speakers? That will eliminate the projector as a potential bottleneck that's lowering the volume. Even if it's optical out, you can buy a digital to analog converter for ~$20 and then plug that into your power speakers.
Finally, if it's only an occasional thing, I wouldn't bother with amps. They can be a good option, but less portable with all the cables - powered bookshelf speakers are a good compromise that can put out a good amount of volume. I have some Monoprice speakers on my computer desk that put out a good amount of quality sound and would easily work as an outdoor temporary setup.
1. see if your media source has separate volume controls, if so, turn that up, either to ~75% or 100% if there is no static
2. turn up the volume on the projector as high as it will go, if it has a volume level setting
3. control sound from your speaker. I have found that some wireless speakers have a lower level when running on battery, so maybe try plugging it into power and seeing if they will go louder?
Also, depending on your source, if it has separate audio outputs (like some game consoles or disc players do) you can maybe configure it so that it's only sending video to the projector, and sending audio out to the speakers? That will eliminate the projector as a potential bottleneck that's lowering the volume. Even if it's optical out, you can buy a digital to analog converter for ~$20 and then plug that into your power speakers.
Finally, if it's only an occasional thing, I wouldn't bother with amps. They can be a good option, but less portable with all the cables - powered bookshelf speakers are a good compromise that can put out a good amount of volume. I have some Monoprice speakers on my computer desk that put out a good amount of quality sound and would easily work as an outdoor temporary setup.
