9v rechargable battery for onboard electronics

erky32

I have a Godin Ultra A6 with hb & piezo, it has o/b EQ preamp which is powered from an o/b 9v battery. Batteries only last ashort while before I start getting distortion esp on the acoustic channel. I assume the acoustic side needs more voltage headroom and so when the battery looses its initial life and the volts get sucked down, then distortion will begin.From what I know rechargables never reach that full alkaline voltage even when fully charged, Ni-cads i believe just 1.2 instead of 1.5, so maybe a 9v only gets to 7.2v ?? ...dunno! Has anybody addressed this situation?, tried rechargables? ....any recommendations for best batteries (i use Enloop 1.5v for my radios and they are brilliant but i dont think they do 9v)

victorludorum

I use a cheapo Uniross one for my Acoustasonic, but it behaves like any other rechargeable where the power level just drops off very quickly. I think the best bet is to buy a few of these and keep them handy as they are cheap really.

viz

I use rechargeables and keep them in one of those round plastic chewing gum containers. It's exactly the right size to hold 1, 2, 3 or 4, and regardless of how many you have in there and how hard you shake them, they will never end up with the contacts touching each other. I cycle 8 batteries through the charging routine, so there's always 4 or so spare. 

mellowsun

You can get rechargeable 9v alkalines. The green ones from Maplin are pretty good, not cheap at 9.99 each but they last well.

Danny1969

Look at the mAh rating, in simple terms that's how much charge the battery can store if you look at it like a fuel tank. That's one indication, the other is the type of chemical contruction, some rechargables are very good for quick heavy loads and will outperform a good Alkaline when drawing 400mA's or so but wouldn't be a good choice for very low current but  long life ... like in a smoke alarm 

I'm surprised about the short life in the Godin, the small signal pre amp draws a tiny current in use, you obviously unplug it when not in use ?

erky32

Thanks for all replies, ...and yes I'm careful to unplug when not in use, but I do notice distortion creeping in after not too long, thats why I wonder if the preamp is very voltage sensitive needing that full 9v, bit wierd because I would have thought a preamp would have negligible current consumption and voltage pull-down. But I also understand that acoustic amps being more hifi need that voltage headroom. I've been looking at Li-ions and some of the later gel ones (EBL) seem to be sitting at 9.6v, (600mAh) probably 8 cell construction, so I might give those a trial. I'm still grateful for all your ideas/experiences if anyone has more to offer before I order some.

maltingsaudio

I never use rechargeables, although I do buy my batteries in quantities, its just not worth ruining a gig for the sake of a couple of quid just my 2 pennorth.