Don Pearce wrote:
Apropos of some stuff we were doing a while ago, here is the pink
noise track from th HFN-RR test disk played on my system, which is:

Systemdek IV
SME 3009ii arm
AT-OC9 microline cartridge

V.nice indeed.


http://81.174.169.10/odds/dspkr/atoc9.gif

It shows an essentially flat response from about 12Hz, with a slight
lift at 10kHz, then returning to the proper level above that. The
recording is made at 96kHz sampling, and it is clear that the test
record cuts off sharply at 20kHz. The cartridge claims to go to 60kHz
(ahem!)

I've offset the levels of the left and right tracks slightly so they
are more visible.

d
I'm quite used to being alone on this, but could you explain a couple of
things please:

How is time represented on the graph?

I look at the graph and I can't see the things you describe:

I'd have expected the db (loudness?!) to remain constant for a flat
response (that is, a straight horizontal line)?

I wouldn't have commented on the 10k blip, but consider the 10-20k range
to roll off?

I've often seen these things in magazines and frankly they've always
been a mystery!

And, clearly not ashamed of public disclosure here, I tried to 'tune' my
system adopting (I think) the same twisted mentality associated with my
interpretation of your graph, and it sounded totally bizarre - bass just
swamped the entire thing.

Thanks, Rob