Scope is great, but without numbers, hard to see if the sound is reaching 0dB or not, is there already some tools for better metering ? At what levels lines on the scope are ?
I would love some more oscilliscope type features. Voltage measurement would be great.
For now this might help:
These figures are from here:
- it just struck me: just from the looks of the er-301 (not to mention its price tag) it seems rather ironic that we still haven’t the most precise sound measurement tool set that we could possibly think of.
- having said that, this community has been asking for better measurement tools for “ages”. Rest assured that the master of ceremony at hand already does have these request on his bucket list. (Though the tracker on the wiki somehow does not reflect it the way I was hoping for.)
- then there is the argument that I heard from several musicians as well as audio engineers That ultimately you’ll have to use (even trust) your ears. While I do agree to a certain degree I also strongly oppose that argument for various reasons…
Now, it feels good to see a reminder of the measurement wishlist in this thread. (Though related requests are already scattered throughout the whole forum) and though we should be clear about the fact that the mc in charge does have more urgent, more radical and more important priorities at the moment: maybe it’s also a good time to discuss a whole set of measurement tools in more detail. So when @odevices get(s) some headroom for this they can base their work on a more differentiated discussion…
Since not all measurement tools are created equal I’d like to ask you boys and girls:
- @onosendai and everybody else of course. Do you have a particular metering standard in mind? Do we need or do we want a whole set of standards for dB metering?
- or will we be satisfied with one but precise metering so that we can compare dB values across the units in the sound computer?
- @warpigs330 and everybody: any particular oscilloscope features that you would like to see?
- how precise do we want a voltmeter to be? (E.g. for calibrating v/oct pots on analog oscs)
- @odevices am I assuming correctly that we won’t be able to put out constant voltages? (Until you’ve revealed the secret missing link expansion module with thousands of cv out jacks of course )
- would anybody else like to see other tools? Which ones?
(E.g. Phase correlation metering anybody?)
- oh here’s a personal wish: I’d love to be able to read the amount of gain reduction in the limiter unit. Maybe it could be a setting in the unit settings so that it wouldn’t eat cpu cycles when turned of. But I manipulate the pre gain there on a regular basis and while I’m recording and in the middle of a complex mix with dozens of limiter units spread all over the patch. I’d love to be able to dial in little and precise amounts of gain reduction in certain places without having to stop the recording. When my untrained ears do hear the difference then it’s already too late. It’s just a personal preference but I consider pumping that is audible to me in some cases to be an unintended effect.
I would love the ability to set triggers, change the time division, stuff like that, though the truly useful aspects of an oscilloscope (like analyzing serial signals) happen at higher frequencies than the ER-301 can interpret. it would be nice to be able to zoom into wave forms on the device itself, rather than take a recording and look at the wave in another program. I would love some basic visualization type options like lissajous patterns or a Fourier analysis, though I don’t really know what you would do with it.
I have been wanting an oscilloscope for a little while, but I have been able to get by with just a multimeter, the arduino serial monitor, and the ER-301 for a little while now.
Also as far as voltage measurements go I believe that using the a-d inputs the first dotted line is ±5 volts and the top of the scale is 10.
as for the voltage to value mapping and due to programmable input ranges you’d better take a look in the graphs on this wiki page
not quite sure about this. as for sample editing purposes it is already possible to
zoom in to the waveform quite accurately. though it’s not the precision i know from my daw the additional possibility to “go to zero crossing” compared with the knowledge that you’d better introduce very short fades (stereo files usually don’t cross zero at the same time) which is also possible at least i come to the same sample editing results as i would with my daw…
don’t know yet why i would go to sample accuracy with an oscilloscope yet… but i’m eager to learn.
Internally, the ER-301 maps external signals from the -10V to +10V ADC input range to the [-1, 1] interval.
I have been wanting to pick your brain about the ADC’s. I have been trying to get a circuit working that I can sample audio cleanly as well as DC sources. The ER-301 does this fantastically, I was wondering if you had tips for sampling audio with DC coupled ADC’s.
+1 for gain reduction display