Hi, guys. Unfortunately, I need to connect a microphone to a DVR surveillance system in order to document some intermittent-but-persistent harassment outside my home. The DVR’s audio input is a simple RCA jack and requires a preamp. I have built some electronic projects, and may try to do a simple preamp, but I don’t know much about mics and cabling. I have one mic, a dynamic “Ampex 2001” with 9’ of cord terminating in a ¼” phone plug, or TS connector. I have read that, with an “unbalanced” signal such as this the cord length should be kept short in order to avoid picking up noise. However, I may need to locate the mic 20 or 30 feet from the DVR.
Q: If I were to locate the preamp near the mic, might I get away with then running the amplified signal another 20 feet or so to the DVR? It seems like the noise problem wouldn’t be as much of an issue after the signal is boosted a bit. What do you think?
And I’ve been looking here and elsewhere at circuits for a preamp. I’ve seen a few, but I’m not sure which one would be the correct one. I don’t need anything fancy, but I think it needs to be appropriate for a low impedance mic, have an unbalanced input(?), fairly high gain (60dB?), and not introduce too much noise. Does this sound about right?
In my dreams I also hope for it to be fairly simple and inexpensive.
I’m not asking much, am I?
Any thoughts will be appreciated. Thanks.
Q: If I were to locate the preamp near the mic, might I get away with then running the amplified signal another 20 feet or so to the DVR? It seems like the noise problem wouldn’t be as much of an issue after the signal is boosted a bit. What do you think?
And I’ve been looking here and elsewhere at circuits for a preamp. I’ve seen a few, but I’m not sure which one would be the correct one. I don’t need anything fancy, but I think it needs to be appropriate for a low impedance mic, have an unbalanced input(?), fairly high gain (60dB?), and not introduce too much noise. Does this sound about right?
In my dreams I also hope for it to be fairly simple and inexpensive.
I’m not asking much, am I?
Any thoughts will be appreciated. Thanks.