In article , Dave Plowman (News)
wrote:
In article , Sumatriptan
wrote:
Good morning experts ;-)

I've been going through my HFN test record. Most of it makes sense but
I don't understand my pink noise results. They show an approximate 10
dB / decade tilt, which is what I would expect from pink noise. For
example, here's a frequency analysis of a 'perfect' pink noise sample
generated by Audacity.

http://www.nu-ware.com/Misc/Screensh...nk%20Noise.png

Here is the result of the HFN pink noise test using my M55E cartridge.

http://www.nu-ware.com/Misc/Screensh...nk%20Noise.png

However, when I look at test results around the web I see essentially
flat curves from pink noise tests. Like this:

http://www.tnt-audio.com/sorgenti/shure_m97xe_e.html

So, what am I missing?

I'd say it's likely impossible to record perfect pink noise to vinyl.

FWIW I checked the 'pink' and 'white' noise bands on a variety of test LPs.
They were all wildly different in ways that didn't simply mimic the
response of the cartridge I was using.

The best way I found to do measurements of frequency response was to use a
stepped or swept tone test band from a test disc.

http://www.audiomisc.co.uk/HFN/LP4/NewLampsForOld.html

shows some examples using the Analog Productions test LP.

Jim

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