I have gigged straight through a regular DI. I was pretty much at the mercy of the Audio Tech, and it did not always go well. A preamp DI would be a lot better as it gives you tone controls at your fingertips.
Sounds like either the audio techs don't know what they are doing, the mixer is damaged, or possibly the mixer is poorly configured. If the problem is on their end, using a preamp is not going to resolve it.
If they can't get enough level, it should not be possible to clip the channel by cranking up the fader to unity.
On an analog mixer you typically solo the channel and adjust the gain so the signal is peaking around 0dB.
Where the channel clips can vary from one model of mixer to the next. From what I remember they usually have 3-9dB of headroom.
On a digital mixer you adjust the gain so the signal is peaking around -12dB.
As you see, this means 12dB below clipping.
If the channel gain staging can be adjusted as I just described without excessive noise, the signal level you are sending is fine.
One possibility is the audio techs have one or more compressors set to really lock down the signal. So they are getting what they need but the compressor is gutting the signal level. If you hit a compressor hard to try and get enough signal, it can definitely cause clipping. Usually you dial in the compressor for the desired amount of gain reduction, and the you adjust the makeup gain, so the nominal level coming out of the compressor is about the same as the nominal level going in. Without this makeup gain, the compressor will nock the signal down considerably.
Another possibility is they have the signal routed to a subgroup and the gain staging is jacked. Or possibly they have assigned a VCA or DCA that is locking down the level.
I am sure there are other possibilities.
the sound folks continue to claim I'm too loud while at the same time don't have enough signal from my amp and can only get me in FOH by moving the fader up to unity. Then claims if they move me up that far it induces clipping. I'm at a loss and confused.
Just reread this. The only scenario I can think of where it makes sense is the PA cannot play loud enough to get over your stage volume. So either you are too loud or the system sucks. AFAIK it's not unusual for Casinos to want to keep the volume down.
If you want to use an amp, consider elevating the cab and tilting it to aim at your head. This will allow you to hear the mids and highs very clearly so you can monitor at a lower stage volume. However, if you like really fat, greasy lows, you will hate it.
.
