Don Pearce wrote:
On Wed, 07 Nov 2007 19:58:47 +0000, Rob
wrote:

Don Pearce wrote:
On Tue, 06 Nov 2007 08:46:47 +0000, Rob
wrote:

Keith G wrote:
"Rob" wrote in message
...
http://patchoulian.googlepages.com/audiosamples

Bottom of the page. Can anyone notice a difference between these two
tracks?
OK, as Don says - for comparisons these are far too long. (When I post
whole tracks it's as much for entertainment value as anything else!)
Yes, sorry about that both, and thanks for taking the time to have a
look/listen. I quite like the track, and it only takes 30s to download
my end. But point taken.

But
I downloaded them, got them into SoundForge and trimmed the starts to
the very note. That allows me to tab between the tracks in different
panes and set the cursor anywhere but at the exact same place on each
track and play from that point. Ctrl/Tabbing *without looking* a few
times will soon have me 'blind' (no idea which track is selcted) and I
can then make a fairly impartial comparison. Doing that any number of
times had me selecting them virtually in turn!

IOW, the short answer is - No, I couldn't pick a favourite or 'better'
one!! One of them (forget which now) is slightly higher output than the
other (LC01?) but not by much...

Well, one cartridge is old (10 years) and one is brand new. I thought I
could hear a difference at first, but now I've 'analysed' them I'm not
so sure ;-)

Back-to-back I can't differentiate the tracks (compressed or
uncompressed), and thrashing them through software (I have a very
limited understanding of what's happening though) shows virtually no
difference - a maximum 1dB variation through the entire frequency range.
The recording settings/hardware was unchanged.

This tells me something about the longevity of these cartridges, and
their consistency between samples over a long production run.

It also leaves me a little uneasy about this method of comparison for
listening to music. The difference in sound wassn't night and day, but I
felt that vocals were more open (slightly less 'bite' but more treble),
and instruments were easier to pick out.

(The MP3ing doesn't help...!!)

No I know - 70meg uncompressed tho but.

Anyways - thanks again.

Rob
The difference you describe could be ascribed almost totally to slight
differences in level. You need to be mega careful in getting them both
precisely the same (try for about 0.1dB) before you try and make the
comparison or you will be fooled.

Differences in level that small generally can't be identified in terms
of loudness, but in exactly those qualities you have described.

d

No changes were made except for the cartridge change - I just wanted to
see what 10 years does to this cartridge model.

From a measurement point of view, it seems nothing - the small level
difference is, i think, a manufacturing anomaly and probably within
tolerance. I need to add that my understanding of the measurments I took
is limited - I just took a plot spectrum of the same(ish) sample of the
music, exported the data to excel, and crunched the numbers. The absence
of the time variable had me stumped. Even so I found the correlation
between the two data sets to be pretty remarkable once the level
difference had been accounted for.

From a listening pov, the compressed samples revealed little or no
difference, despite the level problem. Similarly, I can't reliably
distinguish between the uncompressed samples. And, as you say, the
difference I thought existed between the two carts could be level
difference, although the old cartridge (01) is slightly louder.

This leaves a blind test of the two cartridges, with levels set within
0.1dB, to rule out anything in the recording chain. And at this point I
give up! 'i think it sounds better' is going to have to do, to justify
the 150 quid if nothing else :-)

Rob

There are a couple of problems with your carts, though - most probably
some sort of compatibility issue with the arm, leading to multiple
resonances. Compare with a sweep of my OC9 in an SME 3009ii arm.
Excuse the drawn line on the curve - it was there to show the
effective slope of a flat response. It doesn't have the multiple
glitches that your show.

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

I also used the HFN test disc.

d


That link is returning 'error 404 not found'. I checked the resonance
test on the HFN record - 9Hz IIRC - which the notes say is about right,
but doesn't preclude resonance elsewhere. It's just a standard Project
arm as fitted to a RPM9:

http://www.project-audio.com/main.ph...nearms&lang=en

BTW - that graph was done a while ago, but the setup is basically the same.

I'll take another look at the weekend - it's not as if I don't have a
shortage of TTs/arms ;-)

Thanks for the feedback.

Rob