Recent content by dc2bluelight

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    Separate In and Out interfaces...possible feature request

    Possible feature request.... Is there any way to use different interfaces for input and output? This would be useful when profiling interfaces. Like if I want to test cheap DAC and my input device is an audio interface that is of known high performance. This also implies separate sampling...
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    REW and Testing Electronics - what interface do you like?

    Nice to know that if you have less of a funding limit you can hit +24dBu. But that also confirms that if I needed anything like +30dBu it's going to take an external buffer amp. At that point, +24dBu becomes unnecessary too.
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    REW and Testing Electronics - what interface do you like?

    For audio performance testing my personal "model" would be something like a Tektronix AA501, 100K input, full differential with high CMRR, 100kHz bandwidth or greater, capability to analyze signals as high as 30Vrms (The AA501 could deal with 200V!) and down to somewhere around -40dBv. I don't...
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    REW and Testing Electronics - what interface do you like?

    Thanks. My 2015 MacBook Pro only has a headphone jack, so not really useful. And, Mac line I/O on other models has basically consumer level, and unbalanced. So I use other interfaces. Just wondered what others use. Yes, the current Motu M2 is pretty good, very clean. I have one. It...
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    REW and Testing Electronics - what interface do you like?

    Does anyone else use REW for purely electronic device testing? I use it for all sorts of testing of devices, everything from phono preamps to amplifiers, mixers, transformers, etc. If you do the same kind of thing, what audio interface do you like to use with REW, and why? The requirements...
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    Absolute polarity discrepancy in digital media

    It will probably seem like picking nits, but it's not a switch that selects between absolute and reversed polarity, it just one polarity then the inverted version of it. There can be no absolute because the original polarity and possible inversions in the chain remain unknown.
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    Increase Number Of Filters In EQ

    I've found that the number of filters is usually more than adequate, because you can achieve nothing by attempting such a granular approach as compensating for microscopic response changes. Above a certain Q and below a certain gain, the filters and response changes are inaudible, and spacially...
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    What kind of wire do you use to connect your equipment?

    They accurately state a few principles of physics, then they miss-apply those principles in a way that is nothing but pseudoscience and marketing. "So if we use a magnetic conductor instead of a regular conductor, we can guide the electrons (the audio signal) through the conductor in a very...
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    Absolute polarity discrepancy in digital media

    This gets to the heart of the matter. We know his tests were fully sighted because he derives a preference. We can't assume the switch was instant because he refers to it as being in the digital domain, so it could be either instant or delayed. But no matter, the test is fully sighted and...
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    Absolute polarity discrepancy in digital media

    I don't mean to imply that a polarity flip in both channels is always inaudible. That's just not true, and I'll be happy to post examples where the flip is audible if you like, and under what listening conditions it is clearly detectable. But to imply, as the quoted article does, that nearly...
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    Absolute polarity discrepancy in digital media

    I'll just add this anecdote regarding absolute polarity. Several decades ago I worked with a radio personality with whom I recorded many interviews. The basic waveform of his voice was quite asymmetrical. His voice was edgy, almost raspy in person and in recordings. If you listened to a...
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    Absolute polarity discrepancy in digital media

    An instantaneous polarity flip is often (but not always) easy to hear. But hearing a difference is not the same as determining what is correct (which is subjective, and likely random). Oh, I wouldn't. He's passionately biased, there's nothing scientific about his opinions. Please be aware...
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    Absolute polarity discrepancy in digital media

    The article is 92% hogwash. His sole determination of "polarity" is subjective. In fact, he has absolutely no idea what's correct. The CD production chain does not include a polarity inversion by default. In fact, in the early days this is something we did look at. The first (and even...
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    Feature Request: Distortion vs Power

    The sequence that messing things up is, Generator on, Level Meter on, then start a measurement. When it's done the generator is back on at the previous settings, the level meter is on, but the SPL meter is out of cal, sometimes by a lot. Closing the level meter, turning the SPL off then back...
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    Feature Request: Distortion vs Power

    It would be useful for some test situations to have the level you set on the generator also set the measurement chirp level. The reverse is already true. And if that were an option, then a "Measure Now" button that triggers a measurement without going through the setup/options screen first...
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