Very good. The specs are here: 
[color=#333333][font=arial, helvetica, sans-serif][size=3]SE2-A[/size][/font][/color] 
 
[color=#333333][font=arial, helvetica, sans-serif][size=3]Features : [/size][/font][/color] 
[color=#333333][font=arial, helvetica, sans-serif][size=3]- 2 individual pots - Balance, Volume[/size][/font][/color] 
[color=#333333][font=arial, helvetica, sans-serif][size=3]- Concentric pot - Bass, Treble[/size][/font][/color][color=#333333][font=arial, helvetica, sans-serif][size=3] 
Technical Specifications :  
Bass : +/-12 dB at 100 Hz 
Treble : +/-12 dB at 4kHz 
Balance : MN500K Potentiometer 
Current : 0.16 mA 
Voltage range : 6 V ~ 22 V 
Battery : 9 V Alkaline[/size][/font][/color] 
[color=#333333][font=arial, helvetica, sans-serif][size=3]OUTPUT JACK NOT INCLUDED[/size][/font][/color] 
[color=#333333][font=arial, helvetica, sans-serif][size=3]Very low noise units. I've put them in my project basses and I've never had any problems with them. Will try to record some samples tonight.[/size][/font][/color]