subwoofer wiring noob question

Yeah, RG6 with an RCA terminator, or just an adapter later. If you run that along with the speaker wire, you'd be set for any powered or un-powered sub. Blue Jeans Cable and other recommend the Belden 1694a Precision coax for these runs. I did that for my subs - mostly "just in case"... At least it's not Monster-priced.

Jeff

Agreed. I should have mentioned I have a "normal" RG6 run in my family room to the sub there, and it works fine, too... I'd just terminate in a F-fitting. $.50 to convert to RCA when the need comes.


Jeff

I used RG6 with RCA male to F-type female adapters like Jeff mentioned and an RCA Y-adapter at the sub.

RG6? For a subwoofer? Huh??? Isn't that a bit...ironic?

The Klipsch KSW-10 has speaker terminal inputs, so why not run your speaker wire to the sub along the way?

Your receiver and subwoofer are consumer grade products that use RCA jacks/plugs. Using thick and stiff cable that's more suitable for carrying gigahertz+ RF isn't really ideal for carrying audio that tops out at a hundred Hz or so. A waste of money, really. Since none of your audio equipment uses BNC connectors, what's the rationale for this unnecessary expense?

My advice is to use good quality line level cable with RCA plugs for runs up to about 25 feet or so, maybe twice that when you don't need anywhere close to 20kHz bandwidth. For line level runs much longer than that, it's a good practice to convert the unbalanced consumer line to balanced professional spec cable. Balanced line cables are good for hundreds, even thousands of feet. You'll need a balun or active converter box at each end to convert to/from balanced/consumer.

BTW, if the speaker run is also going to be long, you would be well advised to run a larger gauge (lower number AWG) speaker cable. Lower speaker cable impedance means better speaker control, especially when using consumer equipment that can have mediocre damping factors. One good trick is to use solid conductor wire just like what's used for AC wiring, to get the most bang for the buck. Solid cable is equivalent of stranded cable that's 2 AWG larger. Since it's behind the wall, you don't need stranded wire because it doesn't move after it's installed.

[quote=Speed Daemon;21508829]RG6? For a subwoofer? Huh???

Agreed. We pros run RG-59 for subs.

Could just as well be RG-58. It isn't acting like a transmission line where characteristic impedance counts. The main thing that is important is a high percentage braided shield and a copper center conductor.

Well this pro keeps everything in the digital domain until the outputs of the loudspeaker management system. From there it's standard 600 Ohm balanced line to the amps, and some really hefty cable to the speaker cabinets, using Speakon connectors, of course.

It's more about what's similar than what's different. All three are meant for carrying VHF to SHF frequencies, not baseband audio. Why not use real audio cable? And if you're going to use the speaker wires to drive the sub, a line level signal isn't needed.


Hence the problem. Once more you're choosing RF parts that aren't appropriate for AF use. What's so easy about tracking down oddball stuff like BNC wall plates and making custom cables that are worse than normal ones?


Belkin does make several types of STP cable for audio balanced line use. I don't see it mentioned here, but it's readily available in bulk or with various combinations of XLR and TRS connectors. You'll still need a balun at each end. But since running the speaker wires to the sub will eliminate the need for any other signal source, you're good with a pre-made "zip cord" style stereo pair with molded on RCA plugs for the Wii, provided you can find them in the right length.


It's good enough, sure. My point was that when it comes to speaker cable, there's no such thing as too little resistance. If you welded a dozen gold bars end to end and sold it as "the ultimate speaker cable" I'm sure that a few high-end mavens would pay twice the going price for the gold just to have "the best".

600 Ohm systems are now just legacy equipment. Not much new stuff since the 1960's.

For analog sub-woofer cables and co-ax with a heavy braid shield that mates with your available connectors is good. The longer the cable, the more important the heavy braid.

To err is human. To catch it before making the investment is money in the bank.


I'm confused again. F plugs are also only RF. What's more, they require coax cable. That wouldn't work for your speaker wire. How about using a 1/4" TS jack and plug? One nice thing about TS connectors is that they work equally well with speaker and phono (line) cable. So if you change your mind you can re-use the connectors.


That should be fine for use with common unbalanced "phono" audio cable.

If you mean by "600 Ohm systems" you're referring to the use of active circuits in place of transformers, you're only partially right. When you consider that some of the most costly studio equipment is vintage or built to old specs, the amount of true 600 Ohm equipment is on the rise. The Jensen Transformer company is alive and well and still making their products in the USA. What's old is new again.

Digital loudspeaker management is about as far from retro as you can get, but the last few feet are still analog. That means using 600 Ohm balanced cable, not 150 Ohm AES/EBU digital cable. If it ain't broke, don't fix it.

Sorry to be disagreeing with you again so soon, but using braided shield on audio cables is rather outdated. And weight is no guage of quality. The state of the art shielding uses aluminum foil for 100% coverage. Can't get much lighter than that.

When it comes to long runs (hundreds of feet), using a balanced pair, twisted pair, multiple pairs and more twists per a given length are more important. It's kind of hard to get more than 100% shielding, so...

..on what planet is this true?
Why do you make this stuff up?


No, when using long runs, use a balanced system....ie. differential drivers and receivers over a twisted pair. It doesn't matter if it's got a shield or not...it's balanced/differential...just lilke a telephone line, which is unshielded and not twisted.

So you should use RCA terminations/wallplates for your sub.

I see now. F terminators might work with baseband video. But as you noted, someone would see the F plugs and expect a cable, antenna, satellite or related RF signal to be there. BNC connectors are used a lot to carry video in broadcast/production TV facilities. The problem there is that they have so many cables with BNC plugs at the end, that if they lose a label it might take a while to figure out what that wire is for!

Of course you'll have a lot fewer video cables to choose from, and can use color-coded cable or some other method to make sure the right source goes to the right destination. These days it's just more common to use a digital video transport like DVI or HDMI. That confused me.


Interesting fact: the guy who invented the BNC "bayonet" connector invented the TNC connector later on when he saw the bandwidth limitations of BNC.

Cheers!

The amount of legacy and legacy tribute 600 Ohm equipment made today is trivial compared to the modern style equipment that the B***ger company makes.


Jensen would be out of business if they only sold 600 Ohm transformers


Don't think that I have ever seen a 600 Ohm cable. I have seen pictures of them alongside railroad tracks 50 or 100 years ago.

Maybe you should tell that to our friend Bill Whitlock at Jensen Transformer. As he writes that a heavy braided shield (14AWG) is very important in an unbalanced interconnect.


Foil is good at radio frequency for interference.(which is becoming more and more common) but braid is better for everything else.


Very true, balanced is always better for long runs. (but it's not always available)

No, I'm all booked up telling my elected officials things that all those TV commercials tell me to to tell, rather than just tell them themselves.

BTW, if your only experience with pro audio gear is "alongside railroad tracks 50 or 100 years ago", you really should resist the urge to pontificate about what you don't know. If you want to be contrary just for the sake of being contrary, do it to a mirror, please.

You continue to reveal your lack of knowledge.
600 Ohm audio systems were phased out decades ago...get with the program, please stop embarrassing yourself.

With a comment like that, I can't resist the urge to join in the pontificating/educating:

"600 ohm" is NOT another term for "balanced audio," "electronically balanced audio," or "transformer balanced audio." 600 ohm systems ARE virtually extinct in professional audio, having been replaced by low impedance outputs feeding high impedance inputs. There's no reason to use impedance matched 600 ohm lines unless your dealing with cable lengths measured in miles instead of feet (for example, if you're a railroad).


The impedance of balanced AES/EBU cables should be 110 ohm, not 150 ohm. At any rate, to your point, cable impedance doesn't matter with analog audio over short distances, so 150 ohm, 110 ohm, 75 ohm, or 600 ohm (if you could actually find some) will all work just fine.


F connectors will most definitely work just fine for baseband video. It's very common to find F connectors used for the video input on professional analog CATV modulators.


Wow. Really don't know what to say at the suggestion that it's a problem to use a connector that makes sense because it might be confusing having so many of them.