Taperssection.com

Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: tim in jersey on August 11, 2011, 09:42:53 PM

Title: SPL levels and preamp battery life
Post by: tim in jersey on August 11, 2011, 09:42:53 PM
How do SPL levels affect the battery life of a portable preamp?

I've always thought the higher the SPL, the less gain needed for proper levels and therefor greater battery life. Is my logic sound (no pun intended).
Title: Re: SPL levels and preamp battery life
Post by: tim in jersey on August 11, 2011, 11:28:04 PM
Nope, there is almost no correlation between input levels and power consumption.  Gain is not significantly correlated with current draw in a typical opamp design (for a discrete design, it could vary with gain).  High output levels may draw more current, but that depends on the load as well.  Headphones, yeah that makes a big difference; a 10K line load, hardly any difference at all.

Thanks for the reply. I'll be honest, though. That went completely over my head.

I'm testing 3 7800 mAh lenmar l-series li-ions for runtime. They are all just shy of a year old, and I'm trying to decide if I should invest in a few more cells and chargers to take me through a 3 day festival...

Title: Re: SPL levels and preamp battery life
Post by: tim in jersey on August 11, 2011, 11:30:43 PM
BTW, the "testing" consists of running MK4>kc5>cmc6>xlr>SD 722 (low sensitivity/gain cranked to max) recording me snoring, and the ceiling fan while I'm at work...