Help with Cables "which ones best for my set-up?"

Rise time tracks with HF bandwidth.... Components with a rolled off treble also show a corresponding slowness and greater curve to the corners in their square wave response.... Limited HF response slows rise time, which by definition smears the onset of the signal. In other words, HF response also affects the time domain by determining rise time.

Agreed 100%.

When there is a poor impedance mismatch, can't that result in signal bounce between the terminals, setting up some time smear that could be audible?

That claim is made in the marketing literature of a few specific speaker cables, which are designed to have unusually low "characteristic impedance", in the area of 4 to 8 ohms, such that it approximately matches the impedances that speakers have at audio frequencies.

At radio frequencies, hundreds of kiloHertz and higher, a mismatch between cable characteristic impedance and source or load impedance results in the reflection and time smear effects you alluded to. Those are known as vswr (voltage standing wave ratio) effects. However, those effects do not become "significant" until cable length becomes a "significant" fraction of a wavelength. The wavelength of a 20kHz electrical signal propagating in a wire is in the rough vicinity of 6 miles. The wavelength of a 20Hz electrical signal propagating in a wire is in the rough vicinity of 6000 miles. Even allowing for the fact that in audio very small effects can be audible, the length of a typical speaker cable would certainly seem to be insignificant in relation to those numbers.

Also, at ultrasonic or radio frequencies at which reflection effects may begin to become important, speaker impedance will typically be MUCH different than the 4 or 8 ohm kinds of impedances speakers have at audio frequencies. In the case of dynamic speakers, the impedance will be MUCH higher, due to tweeter voice-coil inductance. Data I recall seeing for a typical dynamic speaker indicated that at frequencies of a few hundred kHz the impedance was around 50 ohms, which actually is a much better impedance match to a conventionally designed cable than to one having very low characteristic impedance.

IMO the reason for the sonic signatures of speaker cables that have very low characteristic impedance is simply that they have extremely low inductance and extremely high capacitance (those being the factors that result in their very low characteristic impedance). For a speaker cable, inductance is normally the more important of those two parameters, and low inductance works in the direction of increasing bandwidth and high frequency extension.

08-07-10: Almarg
While I have no reason to doubt Johnnyb53's sonic observations, the explanation is not quite right.

Slowed or degraded risetime is NOT the result of time-alignment issues, or of some frequencies arriving at different times than other frequencies.

I never said they did. Maybe I didn't explain well enough but I was trying to say that rise time tracks with HF bandwidth. "Fast" cables have HF response well into the MHz or even GHz range. Components with a rolled off treble also show a corresponding slowness and greater curve to the corners in their square wave response.

...
Slowed risetime is the direct result of ATTENUATION (reduction in amplitude), not delay, of high frequency spectral components, which results in turn from bandwidth limitations.

That's what I was trying to say, especially when it comes to detail and clarity. Limited HF response slows rise time, which by definition smears the onset of the signal. In other words, HF response also affects the time domain by determining rise time.

The other part about arrival times was speculative on my part. However, when there is a poor impedance mismatch, can't that result in signal bounce between the terminals, setting up some time smear that could be audible?

All I really know is 1) the Zu cables are wicked fast (1 GHz interconnect; even their iPod cable is 100 MHz) and 2) they transmit tight, focused, and extended bass. 3) They also transmit a lush, detailed presentation with extended and delinated soundstage. I *think* the bandwith/fast rise time has something to do with all this.

While I have no reason to doubt Johnnyb53's sonic observations, the explanation is not quite right.

Slowed or degraded risetime is NOT the result of time-alignment issues, or of some frequencies arriving at different times than other frequencies. Electrical signals propagate through wires at roughly 60% to 90% of the speed of light in a vacuum (that speed being approximately 186,000 miles per second), so the time difference between departure and arrival across the length of a typical speaker cable is utterly infinitesimal, for ALL frequencies.

Slowed risetime is the direct result of ATTENUATION (reduction in amplitude), not delay, of high frequency spectral components, which results in turn from bandwidth limitations.

This Wikipedia article on Litz wire presents some background that is relevant to the type of construction Johnny is advocating.

Best regards,
-- Al

08-07-10: Tvad
Could be, Johnnyb53. I have not directly compared identical gauge cables made of stranded wire, and of several small gauge individually insulated conductors twisted or wrapped or woven together.

Have you done this comparison?

I definitely have woven/twisted separately insulated bundle cables of the same approximate gauge range as 2-conductor multistrgand. My first "upscale" speaker cable was Vampire Wire at a whopping $0.79 per foot. It was over 400 very fine strands (not separately insulated) making for a 10- or 12-gauge conductor. Such a cable offers lower resistance, meaning less insertion loss and possibly better bass clarity and extension. Since this is really just a higher grade zip cord its "improvements" over lamp cord are barely noticeable. However, I have used several individually insulated conductor cables of various configurations with about the same aggregate gauge: Straightwire 8-conductor ribbon at about 14 gauge, various configurations of silver-plated Audio Magic making a 12-gauge aggregate, 14-gauge OCC copper Belkin Silver PureAV Silver Series, PS Audio XStream Bi-Wire, designed as bi-wire from end-to-end: 6-gauge solid core for the bass run and maybe 14-gauge aggregate bundle of silver-plated solid core copper for the treble, and my current favorite, Zu Libtec, which is a bundle of various gauges of copper/silver alloy making an aggregate 10 gauge.

In all cases, the bundles of smaller gauge conductors have a more focused midrange, better transparency and clarity, and a more resolving high treble with fewer spitty sibilants, more realistic cymbal overtones, a more delicate violin tone, etc. And in the cases of the bigger gauge bundles, the bass improves too. The PS Audio and Zu Libtec are particularly good about this. They do it all. I like the Zu better because it manages to do it in a small diameter (about 1/2") easily bendable cable.

Some of the bass improvement may be a time-alignment issue. Different diameter conductors favor transmission of different frequencies, and reduced skin effect (which the small conductor bundles help reduce) results in extended bandwidth. This extended bandwidth results in a faster cable with faster rise times at all frequencies, including bass which tends to be slow. If the fundamental and overtones of a bass note all arrive more simultaneously, that bass note will subjectively sound stronger. And faster rise time at all frequencies means more of the subtleties and delicacies of music--more of the sounds of notes forming, blooming, and fading, more space between notes as the source dictates, more dynamics and more nuance.

Congrats on the nice system!

The single most important factors is that they are the right length, also they are properly termenated.

the rest is mostly cosmetics and how deep into your pockets your arms are willing to reach...related too is how deep into your insecurities the marketing campaigns of cable companies has dug in.

also to remember that what cable x sounds like is person y's audio system is most likely not going to sound like in your audio system. so...

good luck!

08-05-10: Tvad
My experience has been that gauge matters more than materials, construction or brand. A larger gauge provides more richness. A smaller gauge provides more detail, and a more "open" sound.

But if you have a cable made up of several small gauge individually insulated conductors twisted or wrapped or woven together to create an aggregate large gauge (e.g. Kimber 8TC or 12TC) you get the best of both--richness and deep bass control as well as delicacy, air, and inner detail.

I'm currently running Zu Audio's 10-gauge Libtec cable and it definitely provides both in spades (or bananas, nyuk-nyuk).

Another suggestion is to view the virtual systems for sonus faber and mcintosh and see what those folks are running in their rigs. Personally, I like Cardas. Speaker cable that is. Not a fan of their interconnects.

I will venture that you want a rich, full, lush, sound from your system. Although some may argue I would venture that the McIntosh sound, whilst full and dynamic leans to the warmer side of the spectrum. (I do own a Mc amp) Countering this is your TT /Cart set up, which is highly detailed and airy, but nevertheless, will deliver the entire audible in a very balanced, let's say neutral but not a subdued manner. I am not sure how the 2300 phono stage handles the signal however. That was just discussed in these forums as well. Since you seem to want the "Big Tone" I would recommend Jena Labs speaker cables. The warmish Cardas golden reference ICs between the amp and pre, and then, slightly conversely, some HomeGrown Silver Lace which are purely silver, as your phono cables out of the RCA box to the preamp (I own a VPI with the Dyna 20X HO).
These are not really cheap cables especially dependendent on the number of wires in the Jena braid, it can be a downright expensive proposition. Given the expense of the components however, it is a reasonable suggestion.
It is what I use and I am stickin with it.

Just wondering if you've even asked yourself what kind of sound you are looking for. McIntosh equipment obviously has a particular sound but how do you want to augment it? And along with Tvad, just search this thread until you can't read anymore. You may just get an answer you are looking for.

Are you running balanced interconnects from your preamp to amps?