Topic: Lower-than-expected A10 levels... Any ideas? [Solved?]

[rjl]

Hi,

I've been using the SP-CMC-8s > SP-SPSB-20 (12v battery box, no roll-off or volume pot) > Sony PCM-A10 combo for a bit now, and pretty much have the feel of where to start my levels, and adjust from there. However, the other day, at a venue (a decent-sized arena, fairly loud show) that I've taped at a few times w/no problems, I ran into something weird... I started with my levels at their normal 13 - and was maybe halfway to -12db. Over the course of the set I cranked it, in slow increments, all the way up to 21 or 22. No real change. When I got home, the resulting WAV needed A LOT of normalization, and there is also some faint noise to be heard if I listen closely against the speaker, probably from amplifying such a weak signal.

(I initially panicked throughout the set thinking that I may have somehow been recording via the internal mics, in my pocket, but thankfully that was not the case.)

Any ideas? Not even a cause, but avenues to troubleshoot? I checked the voltage on the 12v battery in the box, and while not 100%, it was ~10v. However, if the box were dead, I imagine that I would have had the opposite problem - overloading.

I don't imagine it to be a loose connection, as there were no cuts, and both channels were present and on par with one another, level-wise.

I did a quick scan through the A10's settings, and I can't find anything that may have changed. I literally just turn it on, make sure it's on line-in, manual gain, and pair my phone.

I must be missing something...

[morst]

plug it all back together and see if you can duplicate the problem while at home with the stereo cranked up?

[roffels]

There's been a few posts in the PCM a10 thread about the 12V battery boxes suspected of causing damage to the a10.

[Scooter123]

Switch components and test.

For example, switch out the microphones and AB a recording; Switch out the Battery Box and AB; Switch out the recorder and AB. 

[rjl]

Thanks, all - will try with the stereo when I have the place to myself / won't annoy anyone.

I'll also go back through the A10 thread(s).

[Gutbucket]

I checked the voltage on the 12v battery in the box, and while not 100%, it was ~10v.

Did you check it using a voltmeter/multimeter or battery tester?  If using a voltmeter/multimeter you want to test the battery while under load, otherwise you can get a false reading.  The issue is that a weak battery can show decent open-circuit voltage but the voltage will immediately drop once under load.  You can use a resistor or lightbulb as load, but usually the easiest thing to do is simply to test the battery while its in the battery box powering the micrphones.  A dedicated battery tester should already have a load integrated into it.

[rjl]

I checked the voltage on the 12v battery in the box, and while not 100%, it was ~10v.

Did you check it using a voltmeter/multimeter or battery tester?  If using a voltmeter/multimeter you want to test the battery while under load, otherwise you can get a false reading.  The issue is that a weak battery can show decent open-circuit voltage but the voltage will immediately drop once under load.  You can use a resistor or lightbulb as load, but usually the easiest thing to do is simply to test the battery while its in the battery box powering the micrphones.  A dedicated battery tester should already have a load integrated into it.

Good to know (I had just used a multimeter with the loose battery)!

[rjl]

I checked the voltage on the 12v battery in the box, and while not 100%, it was ~10v.

Did you check it using a voltmeter/multimeter or battery tester?  If using a voltmeter/multimeter you want to test the battery while under load, otherwise you can get a false reading.  The issue is that a weak battery can show decent open-circuit voltage but the voltage will immediately drop once under load.  You can use a resistor or lightbulb as load, but usually the easiest thing to do is simply to test the battery while its in the battery box powering the micrphones.  A dedicated battery tester should already have a load integrated into it.

Good to know (I had just used a multimeter with the loose battery)!

I think that this may have been it. Tried with the stereo on. The battery, under load, was about 7.5v. I swapped in a new one, set it up next to the stereo again, and the fresh battery read a little over 12v while recording. I think I may be good. Will find out in a month or two, as I have some stuff coming up.

Battery was the only thing that I could think of (I had no idea as to others' potential issues w/12v on he A10), but I figured that it would result in ugly overloading rather than a weak signal. I may look into a 9v box, but I like the form factor of 12v, esp the one that I have - it looks like a key fob.

Thanks, all.

[nulldogmas]

Battery was the only thing that I could think of (I had no idea as to others' potential issues w/12v on he A10), but I figured that it would result in ugly overloading rather than a weak signal.

I have definitely gotten low levels from a weak battery — sometimes I can see it decline during a show (often one channel before the other, and sometimes preceded by a waveform that peaks higher in one direction than the other). Hope this turns out to be the fix!

[rjl]

Battery was the only thing that I could think of (I had no idea as to others' potential issues w/12v on he A10), but I figured that it would result in ugly overloading rather than a weak signal.

I have definitely gotten low levels from a weak battery — sometimes I can see it decline during a show (often one channel before the other, and sometimes preceded by a waveform that peaks higher in one direction than the other). Hope this turns out to be the fix!

What's funny is that, in spite of all of this - it's not a terrible recording... but what kills me is that it could have been much better. Live and learn.