In a recording studio there's a recording engineer sorting out the gain levels so the singer doesn't have to step back.

I agree with ghellquist's answer so do that first.

Is your mic XLR cable plugged into one of the four combo sockets on the front of your 18i8 and is phantom power enabled for that socket? For the channel you are using, are the INST and PAD lights off. (They are controlled by the Focusrite Control app that should be installed on your Mac.) You should now be able to use the channel gain control so that the channel isn't clipping when you sing at your loudest.

For the best signal to noise ratio you want your loudest singing to approach (but not reach) clipping on the 18i8. The gain controls on the 18i8 have multi-color LED rings to indicate level. You want the selected channel to occasionally flash amber but never red on your loudest passages. Then use the gain controls in Logic Pro X to set the desired level of your voice in your mix.

In a recording studio there's a recording engineer sorting out the gain levels so the singer doesn't have to step back.

I agree with ghellquist's answer so do that first.

Is your mic XLR cable plugged into one of the four combo sockets on the front of your 18i8 and is phantom power enabled for that socket? For the channel you are using, are the INST and PAD lights off? (They are controlled by the Focusrite Control app that should be installed on your Mac.) You should now be able to use the channel gain control so that the channel isn't clipping when you sing at your loudest.

For the best signal to noise ratio you want your loudest singing to approach (but not reach) clipping on the 18i8. The gain controls on the 18i8 have multi-color LED rings to indicate level. You want the selected channel to occasionally flash amber but never red on your loudest passages. Then use the gain controls in Logic Pro X to set the desired level of your voice in your mix.

In a recording studio there's a recording engineer sorting out the gain levels so the singer doesn't have to step back.

I agree with ghellquist's answer so do that first.

Is your mic XLR cable plugged into one of the four combo sockets on the front of your 18i8 and is phantom power enabled for that socket? For the channel you are using, are the INST and PAD lights off. (They are controlled by the Focusrite Control app that should be installed on your Mac.) You should now be able to use the channel gain control so that the channel isn't clipping when you sing at your loudest.

In a recording studio there's a recording engineer sorting out the gain levels so the singer doesn't have to step back.

I agree with ghellquist's answer so do that first.

Is your mic XLR cable plugged into one of the four combo sockets on the front of your 18i8 and is phantom power enabled for that socket? For the channel you are using, are the INST and PAD lights off. (They are controlled by the Focusrite Control app that should be installed on your Mac.) You should now be able to use the channel gain control so that the channel isn't clipping when you sing at your loudest.

For the best signal to noise ratio you want your loudest singing to approach (but not reach) clipping on the 18i8. The gain controls on the 18i8 have multi-color LED rings to indicate level. You want the selected channel to occasionally flash amber but never red on your loudest passages. Then use the gain controls in Logic Pro X to set the desired level of your voice in your mix.