Taperssection.com
Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: lostockboy on April 26, 2014, 01:07:46 PM
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I used and Edirol R-09HR and with it Sony ECM mic. A couple of years ago I bought a pair Sound Professional-CMC-8 mics (2 mics w/ 1 input jack) which I used a couple of time before I realized that the mics needed there own power supply. I invested in a AT8531 battery box which turned out to be the wrong one because it didn't have the the 3.5m input and output needed for the mics. I then bought a cheap battery box which wasn't much cop either. I then thought I'd bought the correct item which was a Sound Professional-SPSB-11 but when I tried it the Edirol the peak light came on with input level on 1, so third time unlucky. So I was hoping someone could tell me where I'm going wrong. I also bought the SPSB-11 off Ebay and on the description it says it has a "selectable bass roll off (bass reduction) filter is built in which provides seven different bass roll-off frequencies to choose from". From this description I'm assuming there must be a switch to do this or is there something I'm missing. Any help would be appreciated ???
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Did you plug the battery box into the line in or mic in on the Edirol?
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I'm pretty sure I put it into the mic input and that looks like where I possibly have gone wrong? If so, I'm a prize tit. :facepalm: Thanks for the response and I take it that is where I went wrong
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I'm pretty sure I put it into the mic input and that looks like where I possibly have gone wrong? If so, I'm a prize tit. :facepalm: Thanks for the response and I take it that is where I went wrong
Well...it would be the first thing I would try.
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Also those mics will still overload with a battery box with loud shows, so thats a possibility as well and the bass roll off will not prevent overload and with those mics is pointless, if u still get overloaded signal with the line in you may look at getting the 4.7k mod which prevents these from overloading.
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Also those mics will still overload with a battery box with loud shows, so thats a possibility as well and the bass roll off will not prevent overload and with those mics is pointless, if u still get overloaded signal with the line in you may look at getting the 4.7k mod which prevents these from overloading.
I agree completely with Darktrain's response. Let me elaborate a bit...might help explain some.
First off, I'm sorry you're having trouble, but you're at exactly the same point I was over ten years ago when I went through almost the exact same evolution as you are with almost the exact same gear. It was so damn frustrating and for awhile there, it seemed like I couldn't get a good recording to save my life. The combo of the three things already metioned solved the problem for my recording situations. So, the first two you've already got...use line in and a battery box (I agree with Darktrain...don't engage any bass roll-off). The final piece of the puzzle for those mics is the 4.7k resistor mod. It only costs $15 or $20 and if you record loud music, which it sounds like you do, you'll want this mod for your mics. The point is that you probably need all three of the solutions to solve your issue for EVERY recording situation. You wouldn't need the 4.7k mod if you're recording average volume music, but if it gets very loud, those mics will distort on you in the un-modded form.
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I've never really been clear on this. What exactly does the 4.7k mod do? Does it attenuate the signal?
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Thanks for your responses and advice up to now. So what actually is a 4.7k resistor mod and where can I get one from? With all I've spent I may as well go the whole hog and eventually get one when finances allow. Till then I'll continue to use my trusty Sony ECM-719, it's never let me down yet
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Thanks for your responses and advice up to now. So what actually is a 4.7k resistor mod and where can I get one from? With all I've spent I may as well go the whole hog and eventually get one when finances allow. Till then I'll continue to use my trusty Sony ECM-719, it's never let me down yet
see http://taperssection.com/index.php?topic=155550.msg1966002#msg1966002 for a diagram and read the thread for a little more info
several folks here can mod your mics if you don't feel like getting out the soldering iron and doing a small DIY project
< for a little more info, see http://taperssection.com/index.php?topic=94582.0 >
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You were pumping up the mic output too much by running the battery box signal (which raises the mic output) into the mic input (which has a preamp that raises the mic output further). The line-in doesn't have a preamp behind it.
If you ever want to use bass roll-off with the SP battery box, I believe you open it up with a screwdriver to see switches inside. But really...don't bother.
Try the mic -->battbox-->Line-in path and see how your recordings do.
If they are still overloading, you won't have to save up a whole lot to do the mod. Darktrain, who replied to you earlier, can do the 4.7 mod and will charge you a very modest and fair price. He does great work quickly, as I and many other people on this board can tell you. Send him a PM.
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You were pumping up the mic output too much by running the battery box signal (which raises the mic output) into the mic input (which has a preamp that raises the mic output further). The line-in doesn't have a preamp behind it.
A battery box shouldn't add any gain...
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A couple of years ago I bought a pair Sound Professional-CMC-8 mics (2 mics w/ 1 input jack) which I used a couple of time before I realized that the mics needed there own power supply.
I then thought I'd bought the correct item which was a Sound Professional-SPSB-11 but when I tried it the Edirol the peak light came on with input level on 1, so third time unlucky.
So I was hoping someone could tell me where I'm going wrong.
I also bought the SPSB-11 off Ebay and on the description it says it has a "selectable bass roll off (bass reduction) filter is built in which provides seven different bass roll-off frequencies to choose from". From this description I'm assuming there must be a switch to do this or is there something I'm missing. Any help would be appreciated ???
Those mics may or may not require an independent power supply. I think they can run on plug-in power supplied by the recorder. It depends on the volume of the show.
The SPSB-11 should work and will not provide much (or any) gain, so not sure why that issue would arise (though perhaps if acquired used there could be a problem or short in it?).
For quieter shows when I ran the SPSB-11 I ran it into the mic input. The levels (with CMC-25s) were not high enough running it into the line-in to get any signal. I'm told that on a loud show you can run it into the line-in and have enough signal to work with. I've never been to one where that was the case though.
Bass roll off should have little effect on your levels. You don't really need it with these mics though. To turn it on or off you open the case and there is as set of 4 tiny switches in there that let you determine the desired frequency. There are instructions on SP's website at a link (somewhat buried there).
So let's go back to the start:
With the mics and no battery box you would need to plug into the mic-in and have the recorder's plug-in power turned ON (to send power from the recorder to the mics).
*With* the power supply you probably need to plug into the mic-in but you need to have the recorder's plug-in power turned OFF (or you are sending power from the recorder to the power supply!).
"Plug-in power" or whatever that recorder calls it should be switchable in the menus on the recorder.
On a very loud show with the power supply you may be able to run line-in and get enough signal. Plug-in power setting would be irrelevant since the line-in section does not provide that.
I suggest testing at home:
With the power supply plugged into the mic-in with the recorder's plug-in power turned OFF. You should find some (low) levels in that environment.
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Many thanks for the advice. At least all is not lost and there are options open to me
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You were pumping up the mic output too much by running the battery box signal (which raises the mic output) into the mic input (which has a preamp that raises the mic output further). The line-in doesn't have a preamp behind it.
A battery box shouldn't add any gain...
Well, theoretically yes, I guess--the power is going into the mics.
But then...and I've always wondered about this...why is it possible to run mic-->battery box-->Line-in and get a useful level while mic-->Line-in sounds like silence? Hasn't the battery box raised the output of the mic. Explanation would be welcome.