Cables for monitors

Michael Jones

Michael Jones

New member
I need to wire in some cables for the rear surround monitors in my studio.
These monitors are passive Event 20/20's. I'll be using a Hafler 1500 series amp to drive them.

The cables I use now (monster) are too short, so I'll need to get or make some new ones.

From the monitors to the amp is approximately 25'. (It goes down from the monitor, along the inside of the wall, thru a cable trough, and to an amp at the console area.)

The monster cables are a pretty heavy guage, not sure what exactly.

Now for the question:
Can I use the Canare Star Quad cables I'm doing everything else with, to drive the monitors from this amp?
The Star Quad cables are twisted pairs of 20 ga. wire. Seems kind of light, gague wise, but I've got lots of it.

I plan to run 2 sets of cables for each monitor. ;)
 
IMHO (I studied electrical engineering) the hype surrounding shmantzy wire is a lot of hooey. I've never seen a thorough technical explanation of its effects on audio. Yes, they'll say it's electrically better, which is true, but the audio effect of the improved electrical properties cannot be measured. They say people can hear the difference, but I don't believe it. See Ethan's excellent article.

To me, it's kinda like using a pair of car battery jumper cables to connect a 9V battery to your smoke detector. It is electrically better, but it does not result in an improvement in energy delivery.

I'd be glad to be corrected on this, though. :cool:
 
shmantzy wire?

I'm just wondering if twisted pairs of 20 ga. wire is enought to pass 75 watts?
Or do I need to use a heavier ga?
 
I'd go with something a bit more stout than 20AWG.

But I have a tendency to overbuild things, too.:D

Doubling up like you describe sounds reasonable. Especially if you already have a bunch left over, like 100'.............
 
Thanks C7.
Doubling up is just in case one cable should ever fail.
It probably never will, but, it'd be a bitch to have to tear into the wall to replace a cable.
 
Michael, passive speakers should not be wired with shielded cable - the shield both picks up and radiates interference, as well as adds to the capacitance of the cable - over a 25' run this can add up to enough extra capacitance to affect your speaker impedance differently at different frequencies, thereby changing the response of your speakers to something other than what their pretty little graphs claim (this might be bad, might be good, but it WON'T be predictable without a lot of research)

While extra heavy wire is a waste of money, a reasonably solid connection is NOT - For a damping factor of 50 (about average) and runs of 25 feet, 14 gauge is recommended minimum. This is with 8 ohm speakers. Higher damping factors (tighter bass control) would require larger gauge wire - a damping factor of 100 (noticeably tighter bass, all other things being equal) would require 11 gauge wire under the same conditions. For surrounds, 14 gauge would be plenty. It should, however, be NON shielded wire - even Romex would work better than the star quad shielded wire.

If you're still in doubt, I'd do an AB test of your own, just run 25 feet of the leftover star quad to a speaker, listen to some punchy music or full range piano - now, replace the 20 gauge star quad with 25 feet of your romex used to connect your electrical outlets and listen again, making sure there are NO CHANGES to speaker or head location, etc, including volume levels - if you can't tell the diff, I'll be surprised... Steve
 
BTW just in case you ever need to replace said cable, when you put it in use a piece of conduit or leave it loose enough to move. If the cable fails, tie a ball of string to one end, pull the other. go back, tie cable to string. pull string. New cable in ten minutes, no plastering.

Make sure you tie it tight :) .

Also make sure you route A/C, speaker, and mic/line cables away from each other to keep noise down.
 
How come nothing's ever easy?

OK, Steve, you're saying I could just as easily use romex for passive speaker cables?

My front, or Left/right speakers are the Event 20/20 BAS's. And those have braided/sheilded cables. How come passive monitors don't use braided cables? I mean, active monitors are just like the passives, except the amp is built in, right? (I'm just wondering)

I'm using the passives in the rear because, well, because that's what I have.
At some point in the not too near future, I'd like go with all passives - probably the ADAM's. But to do those in the front, I'll have to cable for that now, there's just too many bends and turns, just to get to the cable trough, to try and put those in a conduit.
But the conduit's a good idea, I don't know why I didn't think of that. Brain overload, I suppose.

OK, I gotta go do some soldering for some other audio connectors right now.

Every time I finish something, its one less thing I have to do. I'm getting there!

I did manage to finish the wall plates for the drum room and the vocal booth.
 

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I've been cutting rockwool for days!
I wouldn't wish that on my worst enemy.
Its a god awful mess, and you really need to wear respirators and an enviro-suit. Those suits are like made out of tyvek or something. Tyvek is like... Federal Express envelope stuff. And its the middle of June in central Texas. :rolleyes:
 

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I learn something every day around here.:)

I remember a show on KPFK back in the early 90's called "InFidelity", and they had shows debunking stuff like green markers on CD edges and oxygen-free wire. They said there was no audible difference between #12AWG romex and the high-end stuff targeted for "audiophiles" back then.

I've never heard the bit about shielding adding interference, but now that you mention it it makes sense.

And hell yeah, conduit is always a good idea.:D So are easily-accessable J-boxes!

Thanks Steve!
 
There is a lot of hocus pocus about speaker wire, regarding frequency response, oxygen free, etc.

Yes, copper corrodes very nicely when exposed to air, and forms copper oxide. Copper oxide does not conduct electricity very well.

Once copper oxide forms and coats the strands, it no longer forms as bare copper is now insulated from the air by the copper oxide. Its a self-defeating corrosion process, which is the same for most of the non-ferrous metals like Aluminum.

Stranded wire has more surface area of copper because its made up of many, many strands woven together. So, as the copper oxide forms, it "eats into" more of the copper just because more copper is exposed.

Solid wire helps solve this problem because its essentially one thick strand, therefore only the outer layer gets corroded, as thats all that is exposed to air.

All of the above assumes the copper wire is bare, and exposed to oxygen. If its insulated, only the ends (and a little further in sometimes) will corrode.

Solder, then coat/dip/wrap/cover and its not really a problem.

Sizing is also pretty straight forward. Thicker allows for more current and overall better conductivity. Considering how much more per foot the next gauge will cost you, try to install up a gauge for later expansion. Running cables suitable for 75W might be fine now, but some day you might want to run 200W. Rewiring after you close your walls and ceilings, is the pits.

And yes, you can use Romex for studio monitors. I am. I've run 8-2 (black, white, and bare ground) to each of the monitor locations, thus capable of never being outgrown.

Useful table:
cable1.png

cable2.png



If you look at the chart above, and pick out 8 gauge cable, you can see its acceptable to run 24A through the cable. Most amplifiers run a 40V split power supply, therefore 80V, 24A; 80 * 24 = 1920W

Yeah, thats a lot.
 
Just curious. I wired my monitors with Canare 4S8, which is a 4x16AWG cable. It just has a foil shield, not the braided stuff like in the other star quad cable. Is this a problem?
 
Uh- power amp power ratings depend on voltage.
75w@8ohms=24.5V peak to peak- +/-12.5v
100w@8ohms=28V peak to peak
Small amps don't come close to +/_40 V.

80V=800w@8ohms. That's huge.
 
"active monitors are just like the passives, except the amp is built in" - right - that's why the same cables aren't going to work the same way. The passives need high current, because the power to drive the speakers comes all the way from the amp. This length, if it's more than a couple feet, lets the extra capacitance of the shield "short out" the higher frequencies, change the RLC component of the speaker load, and generally just degrade everything.

Actives use shielded inputs, because they are looking for a line level LOW power signal just like any other signal processor. Their speaker wires are only inches long, and internal to the box. (However, even with actives, cable capacitance can help kill high frequencies with more than a few feet of run)

Time for work, so this post is noticeably shorter-winded than most (oh darn...) Steve
 
boingoman said:
Uh- power amp power ratings depend on voltage.
75w@8ohms=24.5V peak to peak- +/-12.5v
100w@8ohms=28V peak to peak
Small amps don't come close to +/_40 V.

80V=800w@8ohms. That's huge.
Click to expand...


Correct.

Use a crate amp and you'll see that the voltage is higher, generally speaking. my Alesis amps (all three of them) were closer to the 26V peak to peak, but then again, they also didn't put out 500W RMS per side, either.

:)

And no, my surrounds will never see 500W RMS. I just hate the thought of snaking new cable to replace burned wires. For what wire costs, better to go with gross overkill and never think about it again.
 
Lamp Cord from Home Depot.

I watched a really long thread about wires for monitoring. After gobs of gobs of Mastering Engineers weighing in on the specs, sound and costs of wires from Monster and some really expensive wire, a majority of the ME's said that Lamp Cord from Home depot was sufficient to do the job as long as it was copper, and not copper/aluminum. Glenn Meadows was the one who recommended the home depot version as the one he used. Bob Katz, Dave Collins and other pretty much agreed though politics did effect why people would choose otherwise. If you don't believe me then its all here: http://webbd.nls.net/webboard/wbpx.dll/~mastering

Have fun,
SoMm
 
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