Topic: JB3 Line-in recording hiss / beeps / pops

[tms]

Hi TS.com

This website rules! What a great resource of info and inspiration, anyway..

I taped a friend's band the other night, wanted to test out my rig since making some changes from my old one.

My starter rig:  Deluxe (whatever that means, it was $20 extra) cardioids in a gooseneck mount from SP, SP-SPSB-1 battery box, line in to portable Sony MD
My rig in progress:  Nak CM300s, Radio Design Labs STM-2 (got these free, wired up in a radioshack box), Line in to JB3 powered externally by a SLA battery and a radioshack cig lighter power convertor at 4.5v

I ran both rigs just in case something went wrong with the rig in progress. 

The JB3 rig sounded like complete ass.  All kinds of hiss and these noticeable beeps every 5-10 seconds in the recording.  I thought for sure it was the beep from the harddrive writing that is written about on this website.

Luckily the MD sounds great.  My only complaint about those battery box, mini-mic setups is that it has to be _loud_ to get anything like line level out of them.  It was loud and I still had the gain bumped up 2-3 on the MD recorder.

Playing with both setups at home, it turns out the culprit was my RadioShack power supply!  I have a couple kinds and tried them with the same result.  They must not supply a clean voltage supply.  Recording line in using the battery is fine, recording using the external 12v to 4.5v convertor picks up a lot of noise (hiss, clicks and beeps). This may not affect the optical line in, maybe that's why I didn't find any reference to this problem on TS.

I'm going to speak with an electronics guy today and see about building an external battery for the JB3 because I need to run this at a festival.

I also ripped apart my one and only battery to see what's inside.  There are 4 connections but only 2 are for power.  I think the other two are for the battery to communicate with the player.  If they aren't needed, building a big external battery will be easy.  I'll just make a blank plug to slide in the 2nd battery slot and run a bank of batteries outside the player to feed it 3.6 v.

Has anyone done this?  I searched but only found the voltage convertor being used.

Todd in Buffalo

[neutrino]

There are several active posts in the "remote power" section of this board which detail external power sources for the JB3.
dB-

[tms]

There are several active posts in the "remote power" section of this board which detail external power sources for the JB3.
dB-

Right, that's where I saw the idea for the 12 v cig convertor.  Sorry about putting this in the wrong spot.  Can I move it?

After talking with my electronics guy and playing with the battery,  he recommends using the 5V input on the JB3, first cleaning up the power on the cig adapter with a capacitor (~470 uF) and if that doesn't work he's going to rig up a 4705 (?) voltage regulator chip for me.   I think Leegeddy is doing the same thing ?  He says it make very clean power.  That's where I'm at.

I took a bunch of pics of the internals of the battery if anyone is interested I'll email them to you.   There's a little wafer board loaded with electronics in there!  Must be a smart battery.

[momule]

Recording line in using the battery is fine, recording using the external 12v to 4.5v convertor picks up a lot of noise (hiss, clicks and beeps). This may not affect the optical line in, maybe that's why I didn't find any reference to this problem on TS.

FWIW , I have made several SBD recordings with one of my Jb3's Running RCA/XLR > Mini >Jb3 (powered By a 12v SLA using the wallyworld or Sima voltage regulator)