I did measure a difference between my new Kimber 12TC and AudioQuest 14/4

[antcollinet]

The low frequencies make me wonder about noise from outside your room. In one band they add to room modes and in another partly cancel them out. Run at a different time of day.

Maybe do a measure at a higher level. Say 10 db higher, assuming that doesn't stress your gear. This would reduce the influence of noise and result in a reduced difference if external noise is the cause of this.

Another check would be to measure the speaker terminals with an ADC (you'll need to step down the voltage) which I would expect to be pretty much identical with either cable.

Good point.

And another thing to note - assuming OP is in USA or other 60Hz country, the peak variation is at 3rd harmonic of mains frequency. Whats the bet there is some mains hum or other mains related vibration somewhere nearby.

 

[jensgk]

Instead of using a microphone, why not just measure the voltage over the speaker input?

 

[DannyBukem]

Hi Guys... REW files attached.

As i say.... I am a major sceptic about cables... I have regular debates with my mate who spent £2000 on Chord Sarin cables, when we tested them at his house, there was a difference in volume vs standard chord but i was convinced it was placebo!

Happy to re-run tests the other way, i did Kimber first then AQ, so maybe do AQ then Kimber next time?

 

[DannyBukem]

Sorry the files were 19MB: so put them on my OneDrive:

Microsoft OneDrive

1drv.ms

 

[MaxwellsEq]

Happy to re-run tests the other way, i did Kimber first then AQ, so maybe do AQ then Kimber next time?

That's my thinking, simply because (unless something is destroyed or chemically changed) tests should be reversible.

 

[Sokel]

Sorry the files were 19MB: so put them on my OneDrive:

Microsoft OneDrive

1drv.ms

Now we're talking and seems that things are really interesting:
(I choose the 2 directly comparable)

No smoothing

Distances are spot on...


REALLY strange stuff...

 

[DannyBukem]

I've just taken readings again... Obvs my Mic probably isnt in the exact same position as it was yesterday... I took AQ readings first and Kimber second:

Microsoft OneDrive

1drv.ms

 

[Blumlein 88]

Now we're talking and seems that things are really interesting:
(I choose the 2 directly comparable)

View attachment 265966

No smoothing


View attachment 265967

Distances are spot on...


REALLY strange stuff...

Good work. Looks very much like some harmonics of 60 hz noise to me. A fan or refrigerator or AC unit outside or something like that.

 

[DannyBukem]

Btw... the latest readings i increased the volume on the AVR by 5db so this was -25db, the first readings were -30db.

 

[Sokel]

Btw... the latest readings i increased the volume on the AVR by 5db so this was -25db, the first readings were -30db.

Can't find anything directly comparable in the second run,are sure you didn't move anything by accident?
Differences are even bigger but distances are off.

 

[DannyBukem]

The only realistic differences are having it louder by +5db. The mic was put in the same location, middle seat, but this may be off by around 10cm radius from where it was yesterday.

 

[Sokel]

The only realistic differences are having it louder by +5db. The mic was put in the same location, middle seat, but this may be off by around 10cm radius from where it was yesterday.

No,by "off" I mean between the same run of measurements,cause the reflections don't superimpose each other as in the first run.

 

[Blumlein 88]

These are different, but at different frequencies and look like a position problem at frequencies above 1 khz.

Each run of each brand match very well, but the AQ and Kimber are all over the place above 200 hz relative to each other.

I did use 1/12th smoothing to make it easier to see.

 

[DannyBukem]

Thats what i see, surely if it was a measurement issue, the actual runs of the same cable would differ? but they dont.... the same cable seem fairly consistent.

 

[Sokel]

Thats what i see, surely if it was a measurement issue, the actual runs of the same cable would differ? but they dont.... the same cable seem fairly consistent.

Are you sure that you connected both with the right phase?

 

[wwenze]

Well, if you did 5 runs of one cable, then touch something, then do 5 runs of another cable, then each group of 5 runs will have little difference amongst themselves. It's alternating between the cables that removes random variations.

Especially when those look like room modes and one simply has a higher Q so where people stand in the room matters...

In any case, if you find a diff, send the cables to some audio magazine or something and maybe earn a sponsorship.

 

[DannyBukem]

Ah ok…. I get what you mean.

 

[jensgk]

Thats what i see, surely if it was a measurement issue, the actual runs of the same cable would differ? but they dont.... the same cable seem fairly consistent.

When you measure the same cable, do you remove it from the speaker at and put it back on?

 

[jensgk]

Also, the right test procedure would be something like:
1. attach cable 1, and measure it 5 times.
2. attach cable 2, and measure it 5 times.
3. attach cable 1, and measure it 5 times.
4. attach cable 2, and measure it 5 times.
5. attach cable 1, and measure it 5 times.
6. attach cable 2, and measure it 5 times.
7. attach cable 1, and measure it 5 times.
8. attach cable 2, and measure it 5 times.
9. attach cable 1, and measure it 5 times.
10. attach cable 2, and measure it 5 times.
....
19. attach cable 1, and measure it 5 times.
20. attach cable 2, and measure it 5 times.

Then calculate the mean and standard deviation of all measurement points and plot both the means curves, and means+2.3*std.dev and means-2.3*std.dev curves, and see if they overlap

 

[Blumlein 88]

I've done things like this and gotten much better results. The key thing is a steady microphone mount that you do not move, and that you do not move the speaker or speakers. BTW, if you are using two speakers don't. Just use one. You mentioned putting it on a middle seat, that is not going to give good results. A table, a microphone stand or a camera tripod would work. The stands or tripods need to be on the floor. The small Umik tripod will work on a sturdy table top.