COAX (coaxial) and screened cable are not quite the same thing (we won't go there) but otherwise they both have a braid shield (usually).
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Instrument cables are shielded and speaker cable are separate conductors in their own jacket.
You don't want to use an instrument cable as a speaker cable , if a shield wire breaks and pierces the hot jacket you get instant short and bye bye amp.
A speaker cable as an instrument cable will be very noisy because of the lack of a shield!
This is an interesting topic and goes back to early days before 'active' guitars/bass's and valve gear. A non-active guitar/bass really needs to see a resistance of about 1M ohms (1,000,000 ohms!) from the amp for it to work properly, tone control to work right and to sound OK. These really 'high' operating 'impedances' or resistance makes stuff incredibly prone to picking up all kinds of noise from local radio stations and hell knows what if the cable isn't shielded.
This legacy and still popular and non-active instruments still requires the need for good shielded cable. Active instruments mind you offer much better immunity to 'noise' due to their much lower loading requirements..
I've only used a speaker wire as an instrument wire once, by mistake, & the noise was immediately noticeable.
Luckily I've never used a instrument wire for a speaker, because you might not realize until it's too late.
Luckily I've never used a instrument wire for a speaker, because you might not realize until it's too late.
Many instrument cables are unbalanced, so shielding is highly recommended. If the instrument is outputting a balanced signal, then shielding should be used. The plus and minus wires on the cables need to be twisted. I would also like the balanced cables shielded.
Now, how do I know if my signal is balanced or in balanced.
- Most basses provide an unbalanced output signal.
- If you are using a DI [direct input], then the output is hopefully balanced, one of the jobs the DI does is convert the unbalanced signal to a balanced.
- If your cables have xlr plugs, then the cables could either. Usely balanced
- If your cables ha 1/4 plugs, then look at the plug, if is a tip and sleeve, unbalanced,
- >If the tip is trs, tip ring sleeve, it is probably balanced.
- As Reduced risk of damaged tube.amps due to cables becoming under plugged
- The ends are typically rated at 40 amps,
- Safer, no exposed power.
This always seemed very unnatural to me in the past: a non active (so a low level and not amplified) signal has to go into a high resistance amp to sound right? You would expect it would need very low resistance instead. Info [Invalid or Expired Link Removed] cleared that up.
Yup.. We're not too often seeing gear with passive/active inputs, the difference being input impedance.
I note the Rumble 500 and others has a 1M ohm resistor across the input.
This is the sort of discussion that I find extremely confusing. Perhaps it’s because of the terminology.
When I hear impedance and resistance, I assume we’re referring to the flow of current. Since passive electronics in an instrument produce current by induction produced by the vibration of strings within a magnetic field, I assume that the current produced is fairly minuscule. I would think that you’d want as low an impedance or low a resistance as possible so that that minuscule current would make it from the pickup(s) to the amplifier.
Additionally, since the speaker(s) provides the resistive load, you would also want as little resistance/impedance between the amp and the speaker(s) as possible.
Therefore, I can see that the need for a shielded cable would be desirable for an instrument cable since we’re dealing with a tiny current, it seem to me that the shielding would be irrelevant in a speaker cable. Why not just make them all shielded and stop worrying about which is which?
Phew @D M C .. Good questions and I'm not gonna go on too long here as the subject will go on forever. There's some good analogies made.
A passive guitar/bass provides very little current (high impedance) therefore is needs to see a very high load into the amp so its voltage output is preserved. Plug a passive instrument into the line input of a mixing desk, you find it sounds dull and the tone control only works slightly right up one end.
An active instrument on the other hand has a much higher current output (and lower output impedance) and can tolerate much heavier loads. The active electronics buffers everything providing much more power much like an amp driving a speaker but on a smaller scale..
Hope this helps
..
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This confused me in the past as well but check the link I put above.
You want the voltage to be high enough to get a good signal, even though the source level is small.
Instead of thinking of a high load of an amp as a resistor, so reducing the level, to a lower impedance bass guitar output, think of it as a funnel, the source being the wider input and the amp being the smaller output. It will prevent the source signal from draining out too soon and getting too low to provide enough signal into the amp.
If the load of the amp was lower (lower impedance), the funnel would be reverse. The small voltage on the input side would drop considerably more on the output side because of the wide output so it would feed a poor signal into the amp.
Just my simple take on a small part of this subject ;-)
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I think of the cables as hoses, transferring electrons from one place to another.
Here’s an analogy I use, which may be wrong, but...
The instrument’s electronics are like a car’s fuel system: passive electronics being a carbureted, naturally aspirated fuel supply and active electronics a turbocharged fuel system. The pipeline doesn’t really matter, it just moves the fuel from the source to the engine.
The amplifier is the engine in the analogy, converting the fuel into useful work, and the output of the engine is the drive shaft (or propeller shaft for our commonwealth friends) which may be attached to 2 drive wheels (8 ohms) or 4 drive wheels (4 ohms) or some other configuration.
Anyway, the cables (to get back on topic) are a conduit for the fuel/current and should introduce as little resistance as possible to maximize efficiency. Or am I completely off base here?
there are other anologies used such as the electric-hydraulic anology. Where a device similar to a turbo can used as an amplifer
Since speaker cable is not shielded. I was in a band that always had help setting up. So the guy that owned the pa - made all the speaker cable with that orange power cord with speakon connectors.
Worked real well - If it was orange it was a speaker cable - just my 10cents.
Lenny
Worked real well - If it was orange it was a speaker cable - just my 10cents.
Lenny
two good points,
1. Speakon do not fit in 1/4 jacks,
2. Reduces tripping because of visibility
subliminal message ... 5 more days ... 5 more days ... 5 more days ... 
ok I have one more possibly ignorant question.
Is the quarter inch speaker out on the Rumble amps balanced or unbalanced? I was just curious. The recommended speaker cable on a store's website is a TS (unbalanced) cable.
So if a person was to plug a unbalanced cable into a balanced speaker out, wouldn't that degrade the signal? I'm not one to b*tch on websites but if that actually is a problem I'd probably write a friendly note. I'm guessing a great many buyers may not frequent this site hehe. More importantly, I am curious if unbalanced to balanced or balanced to unbalanced degrades the signal or somehow puts it out of phase.
Is the quarter inch speaker out on the Rumble amps balanced or unbalanced? I was just curious. The recommended speaker cable on a store's website is a TS (unbalanced) cable.
So if a person was to plug a unbalanced cable into a balanced speaker out, wouldn't that degrade the signal? I'm not one to b*tch on websites but if that actually is a problem I'd probably write a friendly note. I'm guessing a great many buyers may not frequent this site hehe. More importantly, I am curious if unbalanced to balanced or balanced to unbalanced degrades the signal or somehow puts it out of phase.
Very Good Questions @LeoFromPortland. All speaker cables are unbalanced no matter what type of connectors it may have. The same is true of shielded instrument cables. The only balanced cables are microphone cables. Out of phase issues deal more with speaker cabinets being miswired.
I think you are getting confused with line outs and speaker outs.
Speaker outputs are amplified, in other words they have already been through an amplifier, so you should never plug this into anything other than a speaker (unless you know what you are doing and have special "converters" etc.). There is no such thing as balanced speaker level, speaker lines just have a positive and negative core inside the cable, and the cores are bigger than signal cable. Out of phase is when two speakers are working at opposite wavelengths to each other (not going to explain this now) and is fixed by inverting the positive and negative to one of the speakers.
Line outputs carry signal, they are meant to go to other equipment. These can be balanced or unbalanced, and yes, you need to convert to go from balanced to unbalanced (and vice versa) but some equipment accepts both balanced and unbalanced. If the line is balanced, the cable has three cores (TRS) and if it is unbalnced it has 2 (TS).
Speaker outputs are amplified, in other words they have already been through an amplifier, so you should never plug this into anything other than a speaker (unless you know what you are doing and have special "converters" etc.). There is no such thing as balanced speaker level, speaker lines just have a positive and negative core inside the cable, and the cores are bigger than signal cable. Out of phase is when two speakers are working at opposite wavelengths to each other (not going to explain this now) and is fixed by inverting the positive and negative to one of the speakers.
Line outputs carry signal, they are meant to go to other equipment. These can be balanced or unbalanced, and yes, you need to convert to go from balanced to unbalanced (and vice versa) but some equipment accepts both balanced and unbalanced. If the line is balanced, the cable has three cores (TRS) and if it is unbalnced it has 2 (TS).
