Logically speaking the "at least 10x the largest dimension" seems extremely far. If that is true then floorstanding loudspeakers are all used (and marketed) incorrectly. Most floorstanders are 3 feet (~ 0.9 m) tall. So, by this 10x method, one would need to be listening at least 30 feet (~ 9 m) away to achieve far-field conditions. That just seems ludicrous.
Yep, as mentioned earlier, no bookshelf speaker I've measured shows a significant difference at 2m vs 1m. The iLoud Micromonitors, the smallest speaker I've measured, is 7 inches or 18cm at its largest dimension. I measured it at 50cm(because the manufacturer refers to this distance for max SPL), 1m, and 2m. No meaningful difference. Maybe some of the ripples are slightly different, but the overall measurement is for all intents and purposes identical. Any difference is more likely to come from respositioning my microphone and differences in resolution from different gating.
So while I don't doubt differences exist in the "true farfield", these differences appear to be vanishingly small past a certain distance. Otherwise, as you say, tower speakers wouldn't sound right at typical listening distances of 3-5 meters
I'm more than a bit in this over my head, but sometimes I feel like this is a 'How many angels can dance on the head of a pin.' What I get from the variation in measurements is that the Neumann is the best measuring speaker Amir has tested so far that is commercially available and that there are minor variations due to different measurement techniques that likely don't highlight any differences that would show up in a blind test.
Don't take this the wrong way. The Neumann is good, we all knew that coming into this review. But there are clear inconsistencies in Amir's measurements. With all due respect, from measuring speakers, it's clear that measurements should easily be replicable.
Also the differences described so far would 100 percent be audible in a blind test. Go ahead and apply a 12dB rolloff to your speakers from 7KHz to 20KHz =]
If you're happy with the results, that's awesome. But for those of us interested in the science of how the klippel works and to what degree its results are accurate and reliable, there are some inconsistencies that are worth questioning that are pretty obvious if you've ever measured speakers. This isn't to say the klippel isn't useful or an amazing contribution, but I want to know what it's differences, limits, and advantages are compared to traditional anechoic and quasi-anechoic measurements.