New mics and battery box result in very low recording levels

[druid]

Hi

I'm a real newbie where recording is concerned. I have recently purchased an MZ-RH1 and a set of microphones and a battery box from ebay UK (see link for the binaural mics I bought)

I also bought a battery box so that I could use Line-In to record live rock concerts.

I decided to test the new mics by recording some rock music played on my stereo at a loud but reasonable level. The results using the mics and battery box gave a very low recording level and very quiet recording. I have set the record levels manually and I found that I have to crank the record levels up to max (30 on my RH1) to give only 2 or 3 bars on the RH1 meters - is this normal?

Perhaps the battery box is to blame - It carries a single 1.5 volt AA battery. I have read that most battery boxes use a 9 volt battery. Would a 9 volt supply allow increase the amount of gain I could apply?

(moderator fixed the link so it is clickable)