Maximum Length of Instrument Cable?

[Diggler]

I bought a new processing pedal board; I previously had a rackmounted effects processor. The one bad thing about it is that to use my wireless, I now run from my rackmount wireless to the pedal board, then back to the amp.

Is there any maximum recommended length that I should be sending the signal before it's amplified? I'd like to get a longer pair of cables so that I can route them around the edge of the stage rather than have them underfoot but I'm concerned about degradation or noise.

[anderbass]

With long cable runs, you'll pick up less noise if you hook your processor up through your amps f/x loop.
Line level signals are more resistant to picking up noise than long instrument level, cable runs.

[DubBeats CB]

i heard things over 25 feet will hurt your sound....i usually use 25's but i don't know if there is any truth to the sound thing

[The Golden Boy]

I use around 25' cables as well. I'm happy with them.

[Aarix]

I think it's important to consider purposes.

In the studio, you aren't going to want to use wireless, and 50' of instrument cable. And you'll probably going to want to go through only the effects you are using to get the most out of your tone and minimize noise.

In a crowded bar, who cares if you lose a little sensitive articulation?

[westland]

Use a DI box like the GT Brick, which will allow for 100' of cable without problem

[i like tictacs]

I have a 150 foot instrument cable

I don't use it, but I have it. It's nice to walk to get the mail and play bass at the same time, hehe.

[Rattman]

Originally Posted by i like tictacs

I have a 150 foot instrument cable

I don't use it, but I have it. It's nice to walk to get the mail and play bass at the same time, hehe.

Hahaha! Great mental picture.. thanks for the good chuckle!

[Bob Lee (QSC)]

A lot depends on the nature of the interface. A long instrument cable on a passive instrument--a low-level, high-impedance source--will roll off highs and can introduce noticeable amounts of noise, especially hum and buzz.

The very same cable used on an active, buffered signal source, such as an active bass, an effects box or processor, a typical preamp output, etc., will tend to be much more immune to those problems.

For your application, it probably won't be much of an issue as long as you use cable that has very good shielding, good clean connectors, and good strength and durability. Such cable won't cost you an arm and a leg, either.

[Jagdmusik]

Originally Posted by Bob Lee (QSC)

A lot depends on the nature of the interface. A long instrument cable on a passive instrument--a low-level, high-impedance source--will roll off highs and can introduce noticeable amounts of noise, especially hum and buzz.

Does capacitance have any impact on the length of the instrument cable you can get away with on a passive-bass-straight-into-amp setup?

I generally don't buy into boutique-cable mysticism, but I've been digging around TB recently looking for cable info and noticed that even the skeptics seem to agree that low-capacitance is desirable. I was wondering if this has any relevance to cable length, because I might be willing to bite the bullet on a boutique pricetag if it would give me some objective benefit like, say, letting me run a 25'+ cable while getting no more signal degradation than an ordinary 15' or something.

There are a few pricey cables out there with half the capacitance of ordinary ones... does that mean I can use twice the length without additional high-end loss?

[westland]

I can't seem to find research on instrument cable, but there is a lot on coaxial cable for radio frequencies, and as I understand, the optimal impedences are 33 ohms (it's almost impossible to make a cable at a reasonable price of 33 ohms) 55 and 75 ohms (the last two are supposed to be some sort of compromise), and I presume that the studies that support this have looked a capacitance and distance and so forth ... I'll have to look further. I'm sure radio frequencies are leakier than audio (they always seem to be)

[Bob Lee (QSC)]

Low capacitance in a cable is good for minimizing high-end roll-off--or keeping it well out of the audio spectrum--and thus it allows you to run longer cable before the HF ill effects become equivalent to that of the higher-C cable. How much capacitance is too much depends on other factors, primarily the source impedance of the bass and the input impedance of the amp or preamp. Passive basses tend to have relatively high source impedances, so there exists the potential for the resulting low-pass filter's corner frequency to descend into the audible spectrum. But there are a couple mitigating factors: first, a bass instrument might not suffer much sonically from some loss of the high end of the spectrum; and second, most players tend to attenuate the highs somewhat using the passive tone control, anyway.

If you're using an active bass, it will tend to have a low output impedance, which takes the capacitance issue almost completely out of the picture, except perhaps in extreme cases.

At audio frequencies, the characteristic impedance of the cable doesn't really matter unless it is really long, like a couple kilometers or longer. RF-type coaxial often makes fine unbalanced audio cable, except that it's usually not very flexible.

[westland]

Originally Posted by Bob Lee (QSC)

At audio frequencies, the characteristic impedance of the cable doesn't really matter unless it is really long, like a couple kilometers or longer. RF-type coaxial often makes fine unbalanced audio cable, except that it's usually not very flexible.

OK ... that's a question I was going to ask. I have lots of RF cable, and I can get it in HK for around US$.75 a meter. It is a bit less flexible than instrument cable but at a fifth the price. It works great for short cables; the flexibility becomes an issue for longer cables.

[i_got_a_mohawk]

Does your pedal have an XLR output and does your wireless reciever have an XLR input?

Im pretty sure XLR cables can run alot longer without the signal being as degraded

[Corona_Clyde]

A wireless!!!!