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 Are good speaker cables important?
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Definitely. No signal can travel well on a thin and long wire. Short, well terminated Hitachi 6N type
speakers can truely unlease the performance of the speakers.
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Do both speaker cables need to be the same length? |
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The cables must be of similar length. If the two speaker cables are not close to each other in resistance,
and inductance, the damping will be different. The capacitance will be different and
the high frequency roll-off will be different. These electrical chracteristics affect the stereo image and image depth, as the two channels delicate balance has been disrupted.
There should be no differences in length for shorter lengths of more
than a 2 to 1 ratio, and preferably the closer to the same, the better. Long runs will be more critical, and would need a closer match still.
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Can I coil any excess speaker cable up on the floor? |
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Not recommended because coiling the cable greatly increases the inductance, and other interaction effects
that may cause more than just an extra amount of high frequency roll-off. A snaking "S" pattern will avoid the worst of any interaction problems.
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What is bi-wiring? |
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Bi-wiring is where the crossover inside the speaker has been separated into it's HF and LF sections, and
separate pairs of connecting terminals provided to access those separate sections independently. Normally, the LF and HF crossover sections are in parallel, connected internally to the same single pair
of binding posts.
For single cable use, a set of jumpers is provided to bridge the terminal pairs, paralleling the separated
crossover sections outside the cabinet instead of inside.
Then, separate speaker cables are run from the same amp output to these separated pairs of terminals
at the speaker.
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What good does bi-wiring do? |
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Once the crossovers have been electrically separated, they present different impedance (loads) to the
power amp within their passbands and outside of their passbands. The woofer and corresponding low frequency crossover section will present a low impedance at low frequencies and a high impedance at HF,
while the tweeter section will present a low impedance at high frequencies, and high one at LF's.
One argument about bi wiring is any improvement in the sound is due to the decreased total resistance of
the cable, and this makes the speaker less prone to frequency response
variations due to cable resistance. According to this view, simply running the two cables in parallel at both ends will do the same thing.
With the electrical separation, differing currents will flow within the two cables that make up a
bi-wire set. For the separate cable feeding the woofer
section, a lot of current will flow at LF's but not much current at HF's, and the tweeter cable will have some current flow at HF, but very little at LF's. A division of labor has occurred with bi-wiring, whereby a single cable does not have have to carry the HF currents simultaneously with the LF current.
Two things happen due to this:
1. The losses in the cable due to "eye-squared-are" losses (current squared time the resistance equals voltage drop) are reduced for
each frequency band, so that any tendency for the woofer to modulate the tweeter due to current draw is greatly reduced. This form of IM would be in lockstep with the original signal.
2. The magnetic fields due to the HF and LF currents have also been separated out, and any tendency for
them to inter modulate and cause sonic artifacts has been greatly reduced. This form of IM would be occurring both at the same time, and in a time delayed form due to mechanical resonance and
motor/generator action.
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Can I use the A and B outputs on my receiver to bi-wire? |
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While this would be very convenient, it can only be done if the outputs are placed in parallel,
rather than series. Many receivers and integrated amps that have two speaker outputs will connect them in series when they are both selected
at the same time, to protect the amplifier from an excessively low impedance. Check your owners manual to see how the A and B output are wired when they are both selected. A simple test would be to select them both with a speaker only hooked up normally to one of them, if the sound goes dead, then they are connected in series, and you will need to connect both of the bi-wire cables to one pair of output terminals.
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Should both cables be the same kind? |
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This is absolutely necessary, otherwise the imaging and layering will be affected. Unless the system is
really low Fi, the effect is very prominent.
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Should both cables be the same length? |
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This has already been answered above, but many people seem to feel that bi-wiring is even more
critical, so the warnings in the answer above about matching length for electrical reasons are perhaps even more relevant.
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Are the bi-wire cables that are all in one jacket as good as separate cables? |
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Many cable manufacturer's offer an all-in-one bi-wire cable, primarily for convenience and a tidier wiring
arrangement. On how bi-wiring works, one would realize that placing the cable's magnetic fields in close proximity within the same cable jacket may compromise the bi-wiring
advantage to some degree.
Most experienced audiophiles agree, totally physically separated bi-wire cables tend to sound better than
those in a common jacket. The degree of compromise is going to depend on the spacing between the bi-wire sections within the common jacket, and how much magnetic coupling and
motor/generator resonance are going on inside the common cable jacket.
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How should I terminate my speaker cable? |
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If the amp/receiver has spring loaded terminals, there are
not a whole lot of options. The gold plated pins that are available for such connectors are not an improvement over a good bare stripped wire connection. If you have spring loaded terminals, save your money and forget the gold-plated pins, use the bare wire, twist it hard and tight, and insert it naked. If the total wire thickness allows, double the wire over, and jam the doubled-up wire into the terminal opening, you want as much spring pressure on it as possible. I do not recommend tinning such a connection, and if you have some disposable speaker cable length, about every 6 months, cut off the oxidized exposed bare wire, and start fresh. To prevent oxidation, the terminal and wire can be sealed in hot glue but the glue must not be excessive.
Those with gold-plated heavy duty 5-way binding posts, the choice is clear: gold plated spades, preferably
properly crimped. If you can not make a
proper crimp via a crimping tool, then a proper solder joint will be very close in quality to a good crimp. Amazingly enough, the gold plated spades offered by RS are OK, one of the few RS parts I can recommend at all. The very best spades are the type with compression washers built into the spade fingers, such as the WBT and the Kimber Postmaster spades.
After spade lugs, the next best connection is a gold-plated expanding/locking banana plug. Standard
non-expanding or non-locking banana plugs with a nickel plating are not very good at all, nor are the cheap gold-plated kinds at RS. Monster and WBT make the good types of banana plugs.
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What RCA plugs should I use? |
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For DIY interconnects, one of the best is the Cardas RCA plug. Sonic Frontier's The Parts Connection
offers the SF brand RCA's at a reasonable price for teflon insulated plugs, and Apature has some that are quite reasonable also. WBT has excellent plugs as well.
For all of the above, the best is the non-sliding non-spring loaded ground connection versions, as
these compromise the ground connection too much. They should have teflon insulation, and a good grade of gold plating.
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Can I bundle all my audio cables together with wire ties and stuff them under the rack/shelf? |
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Not a good idea. Power cords radiate a magnetic field and an electric field that is prone to
carrying the interference that rides on all AC power lines to some extent. This RFI and EMI can get into the interconnects and into the unshielded speaker cables, and cause a low level fuzz
or a less than totally silent background, even if it does not cause obvious hum. The interconnects are considered to be shielded in most cases (there are self-shielding types, such as the
Kimbers, etc.), but even the most densely braided copper shield is only
about 97 to 98 % coverage, and even if it is doubled up, or has a foil shield to aid it, 60 Hz and the associated garbage can leak in to some extent. 2% leakage is equivalent to only 34 dB down, although the likely hood of a full bore signal that close to the braid is not that high.
There is also the potential for digital devices such as a CD player to radiate internal RFI and clock
noises into other components via the interconnected outputs, and there is also the possibility of the speaker cable
signal getting into the line level interconnects enough to cause signal deterioration.
So it is best to separate the line level interconnect cables from the speaker cables, and both of these
from the AC cords, all as much as possible. Within these groups, separating the digital CDP interconnect from the others, and keeping a phono interconnect away from all others are also good ideas.
Finally, keeping all cables, but especially speaker cables, away from any metal, especially steel,
is a good idea. Any conductive metal will tend to short
out an electric field, and distort a magnetic one, while a ferrous metal will definitely affect and distort either type of field. A few inches to a 1/2 inch may be all that is needed to prevent the worst of any potential distortions.
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Should I raise my interconnects or speaker cables up off the floor? |
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Lifting the cables from the floor will increase the ‘airiness’ and definition in good systems. However,
care should be taken on the method of lifting the cables. The materials used to lift the cable has a direct impact on the sound quality.
Use good China cups turned upside down or good wooden pecks. The main idea is to space the cables
away from the floor using a dielectric that is better than the carpet or wood floor they were resting on.
An even better solution is to use the foamed polyethylene pipe insulation available at hardware
stores to keep
heat loss from hot water heater pipes to a minimum. The PE is a better dielectric than carpet, and is foamed with a high proportion of air. You can either cut the pipe insulation in sections, and rest the speaker cable on top of the whole cylinder formed by such a section, or slip the cable inside the slitted pipe insulation.
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What is the best cable in the world? |
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This can be very personal and subjective things, and can not be answered without consideration of your own
personal
tastes and the system the cable will be used in. However, 1388.com will suggest excellent cables which are also cost effective. One example is the Audience AU24. It outperforms the DVH MC Silver in 99.99% of the items tested, at less than 1/3 the cost of the MC Silver.
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What is the best cheap cable in the world? |
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Similar situation as above, but compounded by the compromises and tradeoffs that you find agreeable
compared to someone else.
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I read some DIY notes on cables, and want to use some old doorbell red & black
wire I have laying around instead, will it sound as good? |
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B & R wires must be avoided!
Aside from those kinds of issues, it is a forgone conclusion that tinned
copper or PVC will not sound as good as bare copper or a superior dielectric (which includes just about everything else when compared to PVC).
If you want to try a different wire or cable, feel free, however, if you construct a cross-connected dual
coaxial speaker cable using lesser insulation
with a PVC jacket, tinned copper braid and steel core center wires, don't expect it to sound very good compared to the recommended Belden 89259 with it's bare copper braid and center wire and foamed teflon insulation and teflon jacket. And please don't then post and say that "Jon Risch's speaker cable sucks!", because you really haven't constructed one of my recommended recipes.
Another example would be the CAT5 speaker cable recipe. In it, I call out specific CAT5 cables, ones that
have the proper combination of conductors, insulators, etc. Just any old CAT5 cable will not give the same sonic results.
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How can digital interconnect cables from a CD transport to an outboard DAC possibly affect the sound? |
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With digital cables, there are three things that are paramount:
1. proper impedance, proper cable termination, and wide bandwidth. It may be that a
particular cable more nearly matches a systems actual impedance.
2. proper termination includes, but is not limited to, the actual electrical termination inside the
components, as well as the connector on the end of the cable. If the connector is NOT a perfect 75 ohm, 110 ohm, or whatever, it will cause minor reflections in the cable, which makes JITTER raise
it's ugly head again.
3. bandwidth, it is an issue because both the AES/EBU and the SP/DIF interface formats were designed
before Sony/Phillips knew all there was to know about digital problems, and they require PERFECT unlimited
bandwidth cables in order for the transmission systems to be free of jitter. The more limited the bandwidth, the more jitter.
Digital transmission systems are affected by jitter, where the transition from a 1 to a 0 is modulated with respect to time.
There are many ways that jitter can affect the final
digital to analog conversion at the DAC. Jitter on the transmitted signal can be feed through the input receiver, and affect the DAC. It is because the current drain on the power supplies due to the changing signal content and the varying demands made on the power supply to the logic chips and the DAC. This will modulate the power supply rails, and the DAC will convert at slightly different times. The fact that a logical one or zero is detected by the signal swinging through a region from around zero volts to around 5 volts. The digital logic chips detect the change at a specific PERCENTAGE of that total voltage swing.
HOWEVER the power supply gets modulated, it will affect the DAC. One
version of this has been popularly referred to as LIM or Logic Induced Modulation by the audiophile press.
Many of the logic chips in a digital
audio system behave very poorly with respect to voltage fluctuations and noise on the rails and even worse, onto the ground reference point. Logic manufacturers such as TI are advertising the benefits of their latest generation of logic chips that reduce ground bounce. The circuitry itself generates it's own interference, and this can be modulated by almost anything that also affects the power supply or ground.
The amount of jitter that it takes to affect t the analog output of the signal used to be thought of
as fairly high, somewhere on the order of 1,000
to 500 pS worth. Engineers on the cutting edge claim that in order for jitter to be inaudible and not affect the sound of the signal, it may have to be as low as 10 to 20 pS. That's for 16 bit digital audio. That's a very tiny amount of jitter, but the human ear is capable of picking up smaller variations of jitter present.
Computer systems are not timing sensitive. They have wait states to correct errors or to recover the 1's
or 0's. So in this regard, computer systems ARE completely different than digital audio systems. Therefore, cheap cables do not affect performances.
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Is the AES/EBU/SPDIF Digital Audio Interface Flawed? |
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The effective data rate of SP/DIF is about 3 Mhz, and the design of the transmitters and receivers
leaves room for improvements. Maybe if everything else was done right, then cables, etc. wouldn't matter. The system has many things that go wrong and performance is far from ideal.
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