Hej. tak for svaret.
det er 2 stk af de her højtalere:
http://www.yamahaproaudio.com/global/en/products/speakers/msp3/specifications.jspspecs pr. enheds:
Components LF: 10cm (4") cone
HF: 2.2cm (7/8") Tweeter
Enclosure: Bass-reflex Type
Output power: 20W
Input Sensitivity/Input Impedance LINE1: -10dB / 10kO
LINE2: +4dB /10kO
Input Connectors LINE1: RCA pin unbalanced
LINE2: XLR balanced or PHONE balanced
Controls Level Control: LINE1& LINE2
Tone Control: LOW : HIGH
Power SW: On/Off
US & Canadian Models: AC120V 60Hz
Power Consumption: 30W
Type: 2way. Powered speaker
Crossover Frequency: 4kHz
Overall Frequency Response: 65Hz-22kHz
Maximum: SPL 98dB (1m)
Dimensions (W X H X D): (5-11/16" × 9-5/16" × 6-9/16")
Weight: 3.7kg (8.16 lbs)
så de burde godt kunne gå an ik

8-10 timer er mere end rigligt spille tid.
Kan du anbefale et lille godt genopladeligt 12 v batteri i en overkommelig prisklasse ? eller skal jeg gå efter en bil batteri.