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Velleman Microphone Preamp Kit
i have cell phone with week audio output would this work to get a stronger audio output
Do you mean to increase the volume of the audio line out before connecting it to an external amplifier or receiver, like using your phone to play MP3s on you home or car stereo? Maybe, but the stated maximum input voltage is 40 mV, and I am sure any phone with a headphone jack is putting out at least 1.5V. That's almost 40 times the maximum input voltage this says it can handle! However, it looks like one of the raters used it to boost the line out of his TV, and I would have the same expectations of that. It's also important to note that this will only handle one channel of audio, so to use it in the application that I think you are looking to use it for, you would need to buy two of these. If you did this, you would need to build both kits, make some custom interface cables, find an adequate power supply, wire that up, and then balance the two channels at an acceptable volume. Then you can use your stereo to change the volume, and not have to fuss with turning the pots on each board to change the volume.Also, remember these are not pre-built, they are kits that you will have to solder together. It sounds like for your purposes you may be better off just getting something like a Fiio headphone amp or Boostaroo.
Date published: 2012-10-23
Boosting electret microphone
would this product be suitable for boosting an electret microphone signal (3 ohms) to line level (10 ohms)? The speaker amp I am using is line level input only..
Yes this preamp will work for this application.
Date published: 2012-10-12
Would this function well as a guitar preamp?
Possibly. To the best of my knowledge, the standard for an instrument interface is a 1-meg load impedance. It is far from clear how this device is set up. It should be possible to obtain that level of impedance with a few circuit modifications. Also, the LM741 is a very basic op-amp (introduced in 1968). I tend to prefer j-fet input op-amps such as the TLO81. You should be able to swap them at will as there are only two basic families, the OPA07 and the more common LM741. In a pinch, all LM741 family op-amps are interchangeable except in high-voltage applications. I would consider this unit cheap enough to try out. From there it should be easy to sketch out the op-amp circuit you really want (which is why most people use opamps; very easy to get an acceptable design). For a real challenge, try to design it with only a few transistors, again with a j-fet on the input and minimal feedback. The only step up from that brings you back to vacuum tubes which is what all the high-end stuff uses.
Date published: 2011-07-25
What are the dimensions of this piece?
This kit measures 1-3/4" x 1-1/4".
Date published: 2011-03-14
Reccomed Power supply?
Hello.Can you recommend a power supply from Parts Express for this little guy? Thanks!
This amplifier requires a clean DC supply between 10 and 30V. The current draw is little enough that almost any DC supply that PE sells will work.
Date published: 2012-06-09
The mic has batteries and is plugged into correct jack. . .any ideas???
I bought this type for use in my computer which does have a stereo input jack. The mic is powered by batteries instead of a mic jack power source. I contacted Tascam and they suggested a mic pre-amp. This surprised me since cheaper mics have better gain while this Tascam has to be yelled into. My question is. . .could this plate pre-amp work if I used two to maintain the stereo recording.Thanx in advance if you have a clue. I have also tried USB mics but I'm running Window XP Professional so it requires a driver and will not 'sense' a driver when a hardware device is plugged in.
This pre-amp should work fine as a pair. First, though, check the volume settings on your computer. If a cheaper, higher-gain microphone has been plugged in, the computer may have turned its own volume down to compensate.
Date published: 2013-02-16