Has anyone built and/or seen a completely manually operated ADC? The PCM 4220/4222 appear to be capable of completely mechanical control, according to the data sheet, but I do not know of anyone who has done this. The reason I ask is because I was having a conversation with a musician and he was lamenting the difficulty of using software to control his ADC for recording. He really wanted an ADC with manual switches and rotary controls. So, I'm struggling with trying to understand how to design such a beast. Part of my trying to understand is asking questions, hence this post.
The musician's brain is different than the engineer's, hence the difficulty. Forcing musicians to think like software geeks is unfair and not really nice. It's better to just give them something they want and can work with easily.
I'll have to talk to him some more about it, but as I recall, he had a combined mic pre, mixer and ADC that was all software controlled and he didn't like it because he didn't want to sit in front of a computer screen when he was making music.
For the PCM 4222/4220, I suppose at least manual controls for sampling modes and PCM output. I guess audio data format and other things could be useful as well.
Thanks, I'll let him know. The compressor only functions when the signal level is at clipping level, but yeah, probably not the greatest idea. Still, live music is somewhat unpredictable...
Or just turn the darn thing down some so it stays out the red.
the key is to give the guy what he needs, not what he "wants." he wanted "manual control" of his ADC because he was overdriving and clipping the input to the thing.
I realize now it is moot, but forcing musicians to learn is sometimes necessary. try playing a modern synth without understanding its function. As to your original impression of his needs, one does not have to do everything on a computer screen to use recording software. They make all kinds of control surfaces commercially. You get a mixer-like panel of controls, but all they do is feed into the software. But the result is exactly what you described.
the key is to give the guy what he needs, not what he "wants." he wanted "manual control" of his ADC because he was overdriving and clipping the input to the thing.
I realize now it is moot, but forcing musicians to learn is sometimes necessary. try playing a modern synth without understanding its function. As to your original impression of his needs, one does not have to do everything on a computer screen to use recording software. They make all kinds of control surfaces commercially. You get a mixer-like panel of controls, but all they do is feed into the software. But the result is exactly what you described.
For what its worth the Pacific Microsonics is completely manual as are sme of the other pro interfaces.
I agree that the software UI on some cards is completely impenetrable for most people. I still have not figured out the EMU interface. Others are simpler. The ESI Juli@ is pretty straightforward. But it does not have level controls on the input so you need an external mike pre/mixer.
You can strap the PCM4222 demo board interface into specific modes but you may need to get the PC to match/understand the incoming stream.
I agree that the software UI on some cards is completely impenetrable for most people. I still have not figured out the EMU interface. Others are simpler. The ESI Juli@ is pretty straightforward. But it does not have level controls on the input so you need an external mike pre/mixer.
You can strap the PCM4222 demo board interface into specific modes but you may need to get the PC to match/understand the incoming stream.
Maybe he just needs a really big wide range level meter. Something like the American Audio "dB Display".
The Behringer SRC2496 is pretty much a manual ADC; there's a level indicator, input gain, buttons for sample rate and bit depth. I wish the level display was more detailed and bigger, but otherwise I'm very pleased with it.
The Behringer SRC2496 is pretty much a manual ADC; there's a level indicator, input gain, buttons for sample rate and bit depth. I wish the level display was more detailed and bigger, but otherwise I'm very pleased with it.
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If he is clipping a 24 bit ADC in a live situation he is going in WAY too hot, live you have probably got a noise floor at least 30dB above the ADC noise floor so going in aiming to peak 20+dB of so below full scale does not hurt you at all, knock 20dB of the input gain and add it with the monitor volume controls.
That is the problem, not controls and not compression.
Now the digital meters have much to answer for, time was the red lights came on at +6dBm or so and the desk (and recorders) clipped (not too objectionably) at +24dBm or so, digital metering tends to go red 6dB below really nasty clipping.
Regards, Dan.
That is the problem, not controls and not compression.
Now the digital meters have much to answer for, time was the red lights came on at +6dBm or so and the desk (and recorders) clipped (not too objectionably) at +24dBm or so, digital metering tends to go red 6dB below really nasty clipping.
Regards, Dan.
Thanks! I see also that Ross Martin is making some interesting stuff:
Ross Martin Audio
They have a 4222 ADC that looks pretty good. Since I'm such a dummy with digital controls, it may be best for me to just recommend something like that. I also need a good instrumentation grade ADC and what they offer seems to be good. I'll check out Pacific Microsonics also, thanks!
Yeah, Ross's stuff is so cheap that it seems hardly worth building it myself. Just getting boards made would cost me about $150. Then another $100 for the box, add in parts and power supply and I'm well over $300.
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