I just started recording my preamp signal to my computer and applying impulses to it, rather than micing up and recording (since the Sheffields in my 5150 combo can't get me the sound I want.)
Unfortunately through this method, I have to still run my amp as loud as I did when I was micing it in order to get a strong enough preamp signal. I was wondering: Can I just dead patch the effects loop return in order to silence my amp output? I don't really want to have to buy an expensive load box or attenuator if I can achieve near-silent recording without it.
This way, I'm not disconnecting the speakers from the poweramp, so it should still be handling the same load, but with silence coming into the FX return, it should have nothing to play back, right? I've been searching the web all day but can't seem to find any real answers as to whether this will harm my amp, so I figured maybe someone here can help.
Thanks in advance.
It should work like that. The fact that there is no signal being returned isn't a problem, otherwise a broken pedal in your loop would cause your amp to break.
The only thing you'll get is that impulses more often than not tend to be cabinet only, so you're not getting the power amp effect on the signal. This doesn't mean you'll get a bad tone, just not quite the same as going through your amp. Attenuators with lineouts are great for this.