Test Results: Chicago Cable Testing

[xbassman]

I have had one instance when a cable change made a HUGE audible difference.

When I made new speaker cables for my Home Theater system I used 14 gauge copper wire with gold plated banana plugs. I replaced the stock wires that were pretty much the cheapest flimsiest crap they could package with a system though.

After the new speaker cables were installed the high frequencies were greatly enhanced. Everyone noticed right away and I had to spend some time eqing the system to account for the more present high freqs.

That said... the only difference I have ever noticed in instrument cables (@ least as it pertains to bass guitar) is the differences in build quality.

[groutt]

I'd like to hear more about the cable capacitance - pickup inductance - resonance thing.

If I understand the reasoning, it's about having the "right" capacitance. Not the minimum capacitance. Not the most expensive capacitance. But the right capacitance to tune the resonance where YOU want it with YOUR bass.

Could someone do a test... Use short low capacitance cable and add capacitors and see how much difference it makes. Is there a high enough resonance to be noticeable?

EDIT: I think the Q of the resonance is going to depend a lot on the input impedance of the preamp. Higher impeadance will give a higher peak to the resonance and be more noticeable.

[frunobulax]

...kind of makes me question their integrity...

 

 

there you go again.

 

why?

 

because they didn't hear how astonishingly AWESOME your cables are?

 

they probably are good. but are you listening to what a bunch of working musicians are saying here? a well built cable is more valuable than an cable with a negligible sound difference.

[ryanizzle]

especially in the higher frequencies they would have to be tone deaf...

 

 

where does relative pitch come in to the picture?

[MrJoshua]

I'd like to hear more about the cable capacitance - pickup inductance - resonance thing. If I understand the reasoning, it's about having the "right" capacitance. Not the minimum capacitance. Not the most expensive capacitance. But the right capacitance to tune the resonance where YOU want it with YOUR bass. Could someone do a test... Use short low capacitance cable and add capacitors and see how much difference it makes. Is there a high enough resonance to be noticeable? EDIT: I think the Q of the resonance is going to depend a lot on the input impedance of the preamp. Higher impeadance will give a higher peak to the resonance and be more noticeable.

Well, we basically have a simple low-pass filter here where the resistance of the cable and the capacitance between the two leads results in a cutoff frequency of 1/RC, where R is the resistance of the cable and C is the capacitance. I'd be very interested in knowing exactly what the capacitance of some of these high-dollar cables measure out to be, because I suspect they both measure as very small values in any cable. Keep in mind that any decent 20' stretch of copper cable (even taking into account that you have two leads in the cable in series) will have a resistance of less than 0.5 Ohms (assuming 20-gauge conductors). So, to achieve an audible cutoff frequency you'd need a capacitance of about 100 uF. In a 10' cable you'd have only .25 Ohms of resistance (slightly less, actually) so you'd need 200 uF of capacitance, and so on.

And that's just to bring the cutoff frequency down to 20kHz. If you want it lower, you need higher capacitance, because the resistance is going to be basically fixed unless you change the length or gauge of the conductors.

Of course, it's been years since I took a circuits class, and I don't really work with small circuits these days, so it's very possible I'm overlooking something. But ideally you want your cutoff frequency (and thus, the resonant frequency below it) to be located at a high enough point that they'll be inaudible and have no impact on your sound.

EDIT: I see that the capacitance per foot has been added above while I was typing that out (and digging through some notes from college to make sure I was remember things correctly, lol). You're calling 50pF per foot high capacitance? In a 20-foot cable, that gives you a total of 1uF of capacitance. That's going to give you a cutoff frequency of 1/RC = 1/(.5*.000001) = 200kHz.

Now, I can't remember for sure if the 1/RC formula gives us f or W (that's supposed to be an omega; just go with me here) so let's assume it's W. W=2*pi*f, so in that case f = W/(2*pi) so f=31.831kHz.

So our cutoff frequency is either 200kHz or 31.8kHz. Either way, if you can hear that, you're Superman.

Of course, like I said, I could be forgetting something. This isn't my specialty.

EDIT 2: Whoops! Sorry; 1000 picofarads isn't a microfarad; it's a NANOfarad. So in that case, change kHz above to MHz. That's MEGA-Hertz. Yeah. My bad.

[82Daion]

The bottom line is that this cable test flies in the face of actual cable theory and the scientic facts surrounding how capacitance, inductance and conductor material affect what frequencies are heard, and is the first time ever I have seen a group of musicians not be able to tell the difference between cables...kind of makes me questioin their integrity...especially when I trusted them numerous cables...

 

Well, they're sending them back, aren't they? I don't think they'd steal them-considering how much it improved their tone...

 

Of course their integrity is faulty to you-if you gave their test any credit, it would destroy the dubious tenets of your business.

 

If you want, send me the same cables, and I'll audition them to a bunch of audio production students and recording professionals-people who are used to listening closely. I'll even record the results if you like.

 

If you really want to get my attention, build me a cable that'll make my Alembic sound better.

[Kindness]

kind of makes me questioin their integrity...especially when I trusted them numerous cables...

 

 

Take a poll, who has more integrity, you or me. Start the thread. See what happens.

 

This is a personal attack against me and not the first time you've made it. You have avoided legitimate questions, obfuscated by providing illegitimate answers to legitimate questions, resorted to ad hominem arguments, and generally have behaved childish in nearly every instance. There were eleven people in the room yesterday for the testing. In addition, I have had numerous people over to my house, both musicians and non-musicians, that have all listened to all of the cables. No one has heard any significant differences, if any at all. The cables have been played through 5 or 6 different rigs in my house alone with no fewer than 11 different basses, including active and passive. Some of these other "tests" were sighted others were not. Some listeners knew the background story on the cables others did not. Some listeners absolutely believed there would be a difference, but didn't hear one. Other listeners absolutely believed there wouldn't be a difference and didn't hear one. The only person who both believed she was hearing differences and correctly identified the cables in all of these various tests was sarabella, which I've clearly indicated from the first post forward.

 

In any case, I have put the question to you twice already and now pose it a third time, can I forward the cables on to more forumites mlwarriner and 82Daion, for example, for further testing?

[Roguetitan]

If you guys don't have any objections send me some of those cables I have a bunch of musicians here who will give their unbiased opinions as well.

[Thunderbroom]

If you guys don't have any objections send me some of those cables I have a bunch of musicians here who will give their unbiased opinions as well.

Why is your bunch of musicians unbiased and those of us that tested them yesterday biased?

[T. Alan Smith]

Why is your bunch of musicians unbiased and those of us that tested them yesterday biased?

Maybe their not "tone deaf"?

[Thunderbroom]

Maybe their not "tone deaf"?

They will be accused of it after listening to the cables and not hearing a difference.

[MrJoshua]

They will be accused of it after listening to the cables and not hearing a difference.

Maybe you should have played the test for your dogs, to see if they reacted differently to the REAL high end...

[Roguetitan]

Why is your bunch of musicians unbiased and those of us that tested them yesterday biased?

I know you guys were giving your unbiased opinions
and I really don't think the opinions will change from you to us, it would only show that all of us can't be tone deaf and that there really is no noticable audiable difference by just listening between a cheap cable opposed to an expensive one.

However I am a curious creature and would like to find out for my self if i can hear any difference.

[Kindness]

However I am a curious creature and would like to find out for my self if i can hear any difference.

I'm with you. I encourage everyone that has a chance to do it as well.

[Roguetitan]

well I would be obliged to do a test here and invite any forumites in the area to come and participate.

[King Kashue]

well I would be obliged to do a test here and invite any forumites in the area to come and participate.

 

 

 

Personally, I'd still like to see a couple of Carolina area forumites put Lava's ears to the test.

 

Get a digital video camera, tape the whole thing, no editing, completely blind a/b testing. He says the differences are significant enough to notice with only a single listen. Given that, he should not only beat the 50% average, he should be able to pitch a perfect game.

 

If he's able to do that, I'd certainly take a different view of his claims.

[Kindness]

Personally, I'd still like to see a couple of Carolina area forumites put Lava's ears to the test. Get a digital video camera, tape the whole thing, no editing, completely blind a/b testing. He says the differences are significant enough to notice with only a single listen. Given that, he should not only beat the 50% average, he should be able to pitch a perfect game. If he's able to do that, I'd certainly take a different view of his claims.

 

 

I agree wholeheartedly, but I'm not going to be in that area anytime soon. If anyone is, step up and let's end the silliness.

[Thunderbroom]

Personally, I'd still like to see a couple of Carolina area forumites put Lava's ears to the test. Get a digital video camera, tape the whole thing, no editing, completely blind a/b testing. He says the differences are significant enough to notice with only a single listen. Given that, he should not only beat the 50% average, he should be able to pitch a perfect game. If he's able to do that, I'd certainly take a different view of his claims.

This is brilliant. I bet burdizzos would be up for this.


221 mi

[Thunderbroom]

Lavaman...for some reason you've avoided the following posts. Please respond to each post without doing some cut/paste job. Explain specifically why MrJoshua and agedhorse are wrong in their comments.

Well, we basically have a simple low-pass filter here where the resistance of the cable and the capacitance between the two leads results in a cutoff frequency of 1/RC, where R is the resistance of the cable and C is the capacitance. I'd be very interested in knowing exactly what the capacitance of some of these high-dollar cables measure out to be, because I suspect they both measure as very small values in any cable. Keep in mind that any decent 20' stretch of copper cable (even taking into account that you have two leads in the cable in series) will have a resistance of less than 0.5 Ohms (assuming 20-gauge conductors). So, to achieve an audible cutoff frequency you'd need a capacitance of about 100 uF. In a 10' cable you'd have only .25 Ohms of resistance (slightly less, actually) so you'd need 200 uF of capacitance, and so on. And that's just to bring the cutoff frequency down to 20kHz. If you want it lower, you need higher capacitance, because the resistance is going to be basically fixed unless you change the length or gauge of the conductors. Of course, it's been years since I took a circuits class, and I don't really work with small circuits these days, so it's very possible I'm overlooking something. But ideally you want your cutoff frequency (and thus, the resonant frequency below it) to be located at a high enough point that they'll be inaudible and have no impact on your sound. EDIT: I see that the capacitance per foot has been added above while I was typing that out (and digging through some notes from college to make sure I was remember things correctly, lol). You're calling 50pF per foot high capacitance? In a 20-foot cable, that gives you a total of 1uF of capacitance. That's going to give you a cutoff frequency of 1/RC = 1/(.5*.000001) = 200kHz. Now, I can't remember for sure if the 1/RC formula gives us f or W (that's supposed to be an omega; just go with me here) so let's assume it's W. W=2*pi*f, so in that case f = W/(2*pi) so f=31.831kHz. So our cutoff frequency is either 200kHz or 31.8kHz. Either way, if you can hear that, you're Superman. Of course, like I said, I could be forgetting something. This isn't my specialty. EDIT 2: Whoops! Sorry; 1000 picofarads isn't a microfarad; it's a NANOfarad. So in that case, change kHz above to MHz. That's MEGA-Hertz. Yeah. My bad.

[King Kashue]

This is brilliant. I bet burdizzos would be up for this. 221 mi

[collinwho]

I say we lynch him!!!

 

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oops, wrong mob.

 

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back on topic, I'm now convinced on build quality being the main factor in choosing cables. Thanks for taking time to do this test, guys.

[Apendecto]

Here's a question: Lava man lives in Fayetville, NC. Are there folks who live close enough to him to subject him to a blind hear-test? If three or four HCBFers/Talkbassers are close enough, they should go over, and see if Lava Man can beat the averages... If the differences are truly as significant as he says, he should have no problem scoring 100% on a blind a/b... Are they people who can make this happen? Also, Lava man, you continue to evade Isaac's question regarding your statement about Tbroom's bias...As written, you seem to be calling him a liar, and you still haven't responded on that point.

Great post.

Yo.

[Thunderbroom]

I'd definitely chip in for that. We may want to get more than just one person though (Zeromus?), maybe including someone from TB (someone "unconnected") so that everyone can say "yep, the tape is what happened".

 

 

First, let's see if burdizzos will do it AND more importantly if LavaMan will agree. I bet Z-X or rikshaw would do it. If not, someone from TB or eBassist (oldivor perhaps) would be cool.

[MrJoshua]

Lavaman...for some reason you've avoided the following posts. Please respond to each post without doing some cut/paste job. Explain specifically why MrJoshua and agedhorse are wrong in their comments.

I'm actually hoping agedhorse will take a look at the last post of mine in your quote and make sure I'm not oversimplifying or just overlooking something. I normally work with industrial power systems, so low-power systems like this are not my specialty. That said, the math seems pretty straightforward, and a cable shouldn't be that complex of a system.

[groutt]

Well, we basically have a simple low-pass filter here where the resistance of the cable and the capacitance between the two leads results in a cutoff frequency of 1/RC, where R is the resistance of the cable and C is the capacitance. ...

 

 

I think you would need to include the DC resistance of the pickup coil for the R value. Just looking at a google search for bass pickup resistance, seems like 5k-15k is reasonable. So IF my calculatin' is right, with 10k and 1000pF of capacitance, that brings it down to 100kHz.