Analysis Cables

[aron]

I'm still trying to grasp this cable issue. Sorry beat a dead horse!!!!!!!!

So, how does a guitar cable (see the first one) become balance vs. coaxial?

It is a balanced design (not coaxial like others)

http://www.analysis-plus.com/pro_guitarinstrument.html

When I test this cable, what should I test for besides capacitance and resistance?

[dirk]

I'm still trying to grasp this cable issue. Sorry beat a dead horse!!!!!!!!

So, how does a guitar cable (see the first one) become balance vs. coaxial?

It is a balanced design (not coaxial like others)

http://www.analysis-plus.com/pro_guitarinstrument.html

When I test this cable, what should I test for besides capacitance and resistance?

You should do a decent ABX test. http://www.provide.net/~djcarlst/abx_new.htm
It takes only a few minutes.
Make sure you can return those expensive cables, else you will feel depression comming up.

[Johan]

I'm still trying to grasp this cable issue. Sorry beat a dead horse!!!!!!!!

So, how does a guitar cable (see the first one) become balance vs. coaxial?

It is a balanced design (not coaxial like others)

http://www.analysis-plus.com/pro_guitarinstrument.html

When I test this cable, what should I test for besides capacitance and resistance?

I assume they call it balanced because they don't use the shield as a signal carrier ( only attached at one end?), but only the two inner cables...but it wont be truly balanced unless the receiving end is balanced...a guitaramp isn't...also, with that much cable surface area, the internal capacitances shouldn't be significantly lower either, even if the shield isn't attached...
..why do you worry so much about these things Aron?..you are a working musician..I bet, on a loud stage in a noisy bar, you wont be able to tell these cables, soundwise, from any other OK quality cable like ProCo or Whirlwind..seems a little bit to me like audiophoolery for the bedroom rockstar...perhaps I'm wrong....
johan

[R.G.]

aron -

Don't give in to the dark side! These are hifi loonies looking for new territory to sell to.

Dirk and Johan have given you good advice. A guitar is not a balanced source, so balanced cable doesn't help. The amp can't do the receiving end balance to take advantage of it.

Your variables will be capacitance. Period. The series resistance of any metallic conductor from a guitar to an amp is so far below the impedance of the guitar and the amp that it can be neglected entirely.

Notice that these cables are made with two oval braid sections lying face-to-face. That helps make the inter-conductor capacitance ... bigger... than a pair of small twisted wires or a single conductor inside a round shield. The grounded shield will make the capacitance bigger on the outer side of the one conductor that can be carrying signal. I would expect these things to measure and perform worse in terms of treble loss than something like George L's or Belden low capacitance coax. I could be wrong, but that's the first glance.

Your guitar pickup simply can't generate enough current to make the voltage drop across even a long cable matter compared to a 1M input resistance on the amp. So all that heavy copper stranding is simply wasted. Your pickups are inductors between 2H and 10H, so no matter how low or high the cable inductance is, it cannot add any significant inductance to the signal impedance, and it can't block any signal in the face of that 1M amp input impedance. What counts is cable capacitance. THAT will kill your signal dead.

Guitar cables need to be low capacitance, and something under maybe 1K ohms resistance. The lower the capacitance the better, and that's usually a large diameter coax with enough stranding to be flexible and not break under repeated use. Anything else is wasted.

[darron]

the variables that i might consider myself even more so interested in are signal/noise ratios. good shielding and low noise when you move the cable around. i haven't really had heaps of experience personally gauging lots of different brands of cables with instruments that i am familiar with and know what to expect. i suppose the developer actually believes the twisted cable helps? ...

[R.G.]

i suppose the developer actually believes the twisted cable helps? ...

No, it's more like the developer actually believes the twisted cable ...sells.

[soulsonic]

I made a guitar cable from a length of Straighwire audiophile balanced cable like that before with the shield only attached at one end... it was very microphonic. If I still had it, I'd rewire it to see if attaching the shield at both ends helps with the microphonic issues, but it was stolen - which probably gives another good reason not to have expensive cables.

I bet that nice Mogami starquad stuff probably makes a good guitar cable. Of course, since a guitar signal isn't balanced, there really isn't anything being gained as far as any kind of CMRR is concerned when using "balanced" cables. It sure would be nice if balanced guitar signals became popular - it would definitely solve alot of problems.

[dirk]

Just nitpicking:
For a correctly balanced connection from guitar to amp, you only need a balanced input for the amp. Because the pickup behaves just like a transformator. The chassis earth from the amp should then be the shield for the guitar cable, but it must not be directly connected to the pickups! (It should be connected to the strings of cause.)

[PerroGrande]

Dirk,

I was just thinking the same thing! 

You *could* wire-up a guitar as a differential output (balanced) and use something like shielded twisted pair cable to send the signal...  Of course, the amp at the other end would need an appropriate input and you guitar would be somewhat incompatible with the rest of the universe, but it would be an interesting experiment!

[aron]

..why do you worry so much about these things Aron?..you are a working musician..

I know. But it really, really bugs me when my friends who (I really do believe have good ears), tell me that these cables make a huge difference.

He even said he has to alter his amp tone controls because the cable has made such a huge difference and has added more fullness and bass and clarity.

Now, I have heard this from the bass player who has an active bass setup - presumably it's low impedance out right?

Now I hear it from my guitar playing friend who has an Ernie Ball Luke guitar .... HMMMMM also low impedance right - with EMG pickups.

What is going on here. There _must_ be some difference right? If not, I must hear it for myself.

There's a local store selling these for over $100/cable - sometimes up to $150 I think for 10 feet. I really want to test this cable.

[aron]

>Your variables will be capacitance. Period.

OK, then I would assume the capacitance to be less for "good" cable.

OK, here we go, I can't wait to test those cables:

http://www.aqdi.com/cablecap.htm

[soulsonic]

Dirk & John,

Yeah, I don't see why a guitar couldn't be rewired like that... seems easy enough, at least for the average passive pickup. What I'd like to see is for guitars to go to a fully balanced system like microphones. At least we could do a thing like run balanced from the guitar to a buffer with a balanced input, then the buffer can do a nice low impedance out that will have a better time driving long unbalanced cables to the amp.

I'm going to do it!

[dirk]

..why do you worry so much about these things Aron?..you are a working musician..

I know. But it really, really bugs me when my friends who (I really do believe have good ears), tell me that these cables make a huge difference.

He even said he has to alter his amp tone controls because the cable has made such a huge difference and has added more fullness and bass and clarity.

Now, I have heard this from the bass player who has an active bass setup - presumably it's low impedance out right?

Now I hear it from my guitar playing friend who has an Ernie Ball Luke guitar .... HMMMMM also low impedance right - with EMG pickups.

What is going on here. There _must_ be some difference right? If not, I must hear it for myself.

There's a local store selling these for over $100/cable - sometimes up to $150 I think for 10 feet. I really want to test this cable.

What's going on is perseption. And that does not need to the same as reality.
Our senses can fool us:











The "hand" in the window is a mother holding her child.
This is an optical illusion, but all our senses can be fooled in the same way.

Don't dispair, all is not lost!
A decent double blind test can reveal the truth.

So if you want to find out yourself if these cables are worth their money, you need to do a double blind test. If your friends did not do a double blind test, it is very very likely that their perseption is not analog to reality. I can say this with some confidence. Because up till now no person has ever noticed an audible difference, between a normal cable and an exotic cable, in such a test.

[PerroGrande]

Comments on cables and snake oil...

Dirk is absolutely correct.  The only way to really tell if there is *truly* an audible difference is to perform an accurate double-blind test.  If there is, in fact, something other than the placebo effect at work, then a statistically meaningful sample should pick the "fancy" cables as sounding better...  If they, in fact, do pick the "better" cable, then one must understand what it was about the cable that made people select it.  In other words -- is it a statistical superiority in some measurable quantity, or is it a psychoacoustic phenomenon of some sort (harmonic content, frequency curve, etc).  It would be interesting -- and very revealing -- to actually conduct this test.  I suspect that there would be a large number of snake oil vendors objecting to it loudly, however...


Comments on balanced wiring:

Yep -- differential signaling/balanced lines have been in use for small signals successfully for quite some time.  Microphones do it all the time.  Heck -- even computers do it.  10 and 100 Mbps Ethernet operates with a 1V peak amplitude signal on *unshielded* twisted pair (2 pairs, 1 xmit/1 recv).  The segment limit is 100 meters -- far longer than anything we run in the unbalanced world.  Most newer network cable (cat 5e or better) is certified to 350Mhz...  While I understand there are differences between a baseband-style digital signal and what we're talking about, I'm illustrating the point that it seems within the realm of reason. 

[stumper1]

He even said he has to alter his amp tone controls because the cable has made such a huge difference and has added more fullness and bass and clarity.

The first time I did a side by side comparison with a high end cable I "thought" I heard the same thing.  After recording and listening back it became obvious that the added "fullness and bass" was really just less high end.  

[Austin73]

i normally buy guitar cable that looks cool and really expensive! lol Yes I bought a planet waves! lol

Hell at bedroom level does it really matter and I'm sure the wife can't tell.

Just out of interest I have a lot of TV aerial RG59 can I use that for patch cables and the like I'm sure I read somewhere a blues guitarist uses this for his 100ft guitar leads

Would be nice to use the other 50m spare of the cable

Aus

[R.G.]

I know. But it really, really bugs me when my friends who (I really do believe have good ears), tell me that these cables make a huge difference.
He even said he has to alter his amp tone controls because the cable has made such a huge difference and has added more fullness and bass and clarity.
Now, I have heard this from the bass player who has an active bass setup - presumably it's low impedance out right?
Now I hear it from my guitar playing friend who has an Ernie Ball Luke guitar .... HMMMMM also low impedance right - with EMG pickups.
What is going on here. There _must_ be some difference right? If not, I must hear it for myself.
There's a local store selling these for over $100/cable - sometimes up to $150 I think for 10 feet. I really want to test this cable.

Just be sure you can return them. And do yourself a favor - set up a test where you cannot prejudice the results by knowing which cable is which, nor can any helpers "telegraph" the knowledge of which is which to you, perhaps unconsciously as in "Clever Hans".

One important test is to see if you can tell which is which without knowing ahead of time. Many times, the first test is to just alternate the two randomly and see if you can pick out which is which at more than a 50% rate like you'd get from guessing randomly. If it fails that one, no preference test means anything, does it?

Finally, for a lucid send up on cables and other stuff, go read http://sound.westhost.com/cables.htm, especially the part on "Interconnects". Remember that guitar signals are much LOWER frequency range than general hifi.

[nooneknows]

I am a so-called audiophile and I can say cable can make difference in a well set up hifi system (loudspeakers in the right position, good amps, etc.), I remember a good number of afternoons passed making blind tests with my friends, switching from one cable to another with significative results.
But guitar is a different beast: the frequency range is narrow and amps and effects in the signal chain are everything but hi-fi system components.
Most important thing for me is the fact (even if the cable could really make any difference and I have some doubt with guitars) I can't see any reason at all to look for hifi: we're talking about musical instruments and not system to reproduce recorded sound of musical instruments.
I still think, in my romance view of this stuff, we're here making music, not broader bandwidth !
Ciao,
Marcello

PS. BTW, I use a flexible type of RG58 for cables, very cheap, very effective.

[Gus]

Active that might be a hint.  Maybe the cable has a lot more capacitance and is interacting with output of the circuit.

If you can get a pulse generator.  Inject a pulse at the guitar/bass input to the amp section.  Use a 1meg resistor at the other end of the cable.  Use a scope to look at the signals Calibrate the scope probes,  Then look at the input to the amp the output of the amp( adjust the controls to change the shape full treble might be interesting  Then look at the signal across the 1 meg at the end of different cables with t e controls set the same.

Get a two channel scope one channel to the in of the cable and the other to the out.  Invert one channel and sum then together this shows the difference in the signals.  This only checks the cable, to check the amp cable interaction one would need to get the tone controls as flat as possible to do the invert and sum test(invert if the amp is not inverting as it is built).

Maybe the active amps "don't like" the extra cable cap "hanging" on the end of the circuit and might cause the amp to become somewhat unstable.  This might show up as extra ringing on the waveforms.



What active amp in the bass?   maybe there is a schematic of the circuit we can look at.

[aron]

>After recording and listening back it became obvious that the added "fullness and bass" was really just less high end.

This is what I am thinking. Exactly this.

Another thing I could try is to record the guitar into my computer (with guitar input) on a recording interface. I should be able to hear and see the difference.

Aron