Topic: Maha 9.6v vs alkaline 9v for Denecke PS-2/km184

[su6oxone]

Just got a Maha 9.6v rechargeable battery and tested it with the PS-2 connected to Neumann km184 mics and an R-09.  With the 9.6v battery (new, charged for the first time) it ran for about 2.5 hrs and then couldn't power the mics anymore.  The low-batt LED came on before the 2.5 hrs though, and stayed on for hours (overnight, more than 12 hours) afterwards.  By comparison, a standard duracell 9v alkaline battery powered the mics for about 6 hours before quitting, and the low-batt LED came on about an hour before it died (and the LED went out at that point too).  I'm a bit disappointed at the significantly shorter duration of the 9.6v Maha vs the 9v battery, but I'm hoping the battery life will improve after a few charge-discharge cycles. 

[bluntforcetrauma]

I also have the Maha 9.6 but i think the akaline 9v gets better life.  More reliable.  I also have the Denecke PS-2 and also a sonosax pre running on alkaline rather than the Maha 9.6.  Once the NIMH starts running low it really takes a dive.  I know buying alkalines each time is a $$ but I like the reassurance of getting the show.

[su6oxone]

I also have the Maha 9.6 but i think the akaline 9v gets better life.  More reliable.  I also have the Denecke PS-2 and also a sonosax pre running on alkaline rather than the Maha 9.6.  Once the NIMH starts running low it really takes a dive.  I know buying alkalines each time is a $$ but I like the reassurance of getting the show.

Thanks for sharing your experience with the Maha 9.6v.  I'm going to test these at a loud show and see how well and how long they perform at a real show.  If it can't last a good 2.5 hrs then I'll have to return the charger and go back to alkalines. 

[Gutbucket]

Did you use one of the recommended Maha chargers for 9.6v batts?  Supposedly regular 9v chargers will not charge the higher voltage batts completely.  Also, new NiMH batteries require several usage cycles (charge, drain, charge again) to 'form' and reach their full capacity.  From what I've read some need up to 10 cycles to reach their full potential.

I just ordered four Maha 9.6V's (and a bunch of low self discharge AAs & AAAs) anlong the recommended Maha chargers yesterday, so I'm not speaking from experience but I did a good bit of research last week. The Maha 9.6v batts have a 230 mAh rating.  Disposable alkalines generally have a higher mA rating so should last longer, but the voltage may taper off more over use.  For my application (Church Audio CA-Ugly preamps) I want the slightly higher, steady voltage and flatter discharge curve and as long as I can get enough runtime its all good.  Enough being the key word of course.  Time will tell.

Here's a link to discharge curves and mAh ratings for standard Alkaline 9Vs under various high current loads.  I'd like to find the same for the rechargeables.

[su6oxone]

Did you use one of the recommended Maha chargers for 9.6v batts?  Supposedly regular 9v chargers will not charge the higher voltage batts completely.  Also, new NiMH batteries require several usage cycles (charge, drain, charge again) to 'form' and reach their full capacity.  From what I've read some need up to 10 cycles to reach their full potential.

I just ordered four Maha 9.6V's (and a bunch of low self discharge AAs & AAAs) anlong the recommended Maha chargers yesterday, so I'm not speaking from experience but I did a good bit of research last week. The Maha 9.6v batts have a 230 mAh rating.  Disposable alkalines generally have a higher mA rating so should last longer, but the voltage may taper off more over use.  For my application (Church Audio CA-Ugly preamps) I want the slightly higher, steady voltage and flatter discharge curve and as long as I can get enough runtime its all good.  Enough being the key word of course.  Time will tell.

Here's a link to discharge curves and mAh ratings for standard Alkaline 9Vs under various high current loads.  I'd like to find the same for the rechargeables.

I did use the Powerex/Maha recharger that they recommend for use with the 9.6v rechargeables.  After a few charge-discharge cycles, the 9.6v batteries are now powering my mics for about 3 hours, compared with about 6 hours for alkalines.  With 3 hours though, it'll get me through just about any single act, so if I bring two of them I should be good to go for an average show with a headliner and an opening act.  For festivals, 2-3 9v alkalines per day are sufficient.  If you're using the 9100 though, a single alkaline 9v will go a long time (I would use them for at least 20+ hours each), although if you use the Maha 9.6v and recharge after every few shows that would be pretty reliable I would say. 

[Gutbucket]

Thanks for the update.  Batts & chargers arrived this morning and are charging now.  I plan to plug them in to run them down and recharge a few times to test longevity and properly 'form' them before taking a chance on not making it through a recording.  I'm sticking with the alkalines for tonight, but maybe I'll run them tomorrow.

[su6oxone]

Thanks for the update.  Batts & chargers arrived this morning and are charging now.  I plan to plug them in to run them down and recharge a few times to test longevity and properly 'form' them before taking a chance on not making it through a recording.  I'm sticking with the alkalines for tonight, but maybe I'll run them tomorrow.

Cool, good luck with these Maha 9.6v batts... I'll update with a real life test run at a show when I try it out.

[Gutbucket]

Charged the 9.6v Mahas as soon as I got them and they measured over 11V. Ran them down in both CA-Uglies with 4060s attached overnight and they still measured 10V in the morning, dropped to 7V by the time I left work for lunch and 2V when I got back.  Recharged yesterday afternoon and ran them for real last night.  After 4 hours they still measured 10.5V each.   Happy about the high volts & looks like they'll work well for my needs as long as they continue to perform.  Without a low battery indicator on the CA-Uglies though they are bound to bite me at some point down the road unless I can catch impending failure by measuring voltage after use, finding it starting to drop off and retiring them before they quit early.  Just wondering if that will happen in a year, two, three...

[su6oxone]

Well, I've used the Maha 9.6v rechargeables successfully to power Neumann KM184 mics with a PS-2 for several shows, ranging from <1hr to 2.5hrs without any problems.  Tapes came out great, without any issues at all.  I'll be using these only from now on, with alkaline 9v only for festivals and artists who play long shows (2.5hrs+).