24V Mod white noise on low battery (Blackouts)

[h.e.l.shane]

(this is a repost from the MLP forum, but i thought i'd dump it over here too)

Ok... this is the first time i ran across this..


EMG Blackouts with a 24V mod cell


I had a customer bring his guitar in because it was making a white noise sound from the pickups (very similar to the sound of a non tuned radio station)


FIRST thing i ask.. did ya check the battery.... Yep..


So.. I plug it in..


Sounds great..


for about 30 seconds.. then the white noise starts and gradually gets louder and pickups get dimmer.. all three switch positions...


WTF?? Sounds like a cap draining...


Look at wiring.. all good.. continuity good.. grounds correct..


lets look at battery anyway..


its got one of the 2X23A 12v battery packs in it, like this





Check it with the DMM ...... 9v.... OK.. thats not 24V and thus the batteries are dead for the type.


but 9v should still run the circuit.. whats going on here :hmm::hmm:


so I plug the guitar it in and start strumming.. and hook the meter up and watch.. after a few seconds voltage starts to drop.. when voltage hits about 5V the white noise starts and gets progressively worse... until the batteries tank at about 3.5 volts (1.75 each)


makes perfect sense.. the preamp in the pickup is designed to run at 9V, starving it of voltage causes it to clip, distort and hiss..


But why haven't I noticed this on a 9v.. :hmm:


well, thats due to the discharge of a 9v, it hits about 6V and DIES...


as shown here





Apparently.... These little 12V 23A batteries don't die like 9V batteries which pretty much go from 6v to dead in a heartbeat .. these 12v bastids tend to "strangle out" like I noticed on my meter..








SOOOOoooooooo if you've put one of those Ebay 24V mods packs in your guitar.. and it starts to "hiss" or "fuzz"


don't freak.. change the batteries

I haven't tried it, but i can imagine it happens with EMG's too

[toejam]

EMG Blackouts with a 24V mod cell

:think: EMG is EMG. Blackouts are Seymour Duncan. Anyway, both of those are designed to work on either 9v, 18v or 27v.

[jdr94]

i feel that blackouts sound better at 9v and emgs at 18. i dont see the point of 12v.

[84sups]

I'm not an EMG fan but with 18 volts they sound so much better. Blackouts sound amazing out of the box