# Which cable run... coax or speaker?



## Sonnie (Apr 11, 2006)

I'm gonna have a long run from the front to the back of my room with my DIY sub. I'm trying to figure out if it would be better to place the amp up front and make two 30' speaker runs or place the amp in the back with the sub and make a single 30' coax run. Is it six of one, half dozen of another?

Currently I have a long RCA cable running from my BFD to my SVS in the rear and I've not had any problems. I suppose that would be easier. It's easier for me to hide the coax that it is two pairs of speaker wire.


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## Otto (May 18, 2006)

Hey Sonnie,

What you need to do is run firewire to a DAC _co-located _at the sub with the amp! :R 

Seriously, though, that _would _take care of these types of concerns... :T 

Since we don't have anything like that (yet), I think that noise-wise you would be better off to run the speaker wire. Not only is is less-prone to picking up noise over that long run, but you also won't be _amplifying _that noise, either.

OTOH, lots of us have long cable runs to subs or sub amps, and most of the time it's totally fine. As you know, a long run of balanced signal is another good option if you have it. Can you do a balanced signal out of your BFD to your amp? That's how I'm doing it, and it works nicely.


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## Sonnie (Apr 11, 2006)

Yeah... I can definitely do balanced. The path will most likely be from the BFD to a Behringer CX2310 crossover then from it to a Behringer EP2500. The 2310 and 1124 have balanced inputs/outputs and the 2500 has balanced inputs. I'm not all that familiar with balanced inputs and outputs, but that sounds like a plan to me. So all I really need is XLR cables. :scratch: I wonder though... from my Yamaha receiver to the BFD will not be balanced, so will the connection from the BFD to the CX to the EP still be balanced? I'm slowly learning!



> What you need to do is run firewire to a DAC co-located at the sub with the amp!


Oh yeah... cute... really cute! addle:


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## bobgpsr (Apr 20, 2006)

Sonnie said:


> I wonder though... from my Yamaha receiver to the BFD will not be balanced, so will the connection from the BFD to the CX to the EP still be balanced?


Sure! No problem with the BFD outputing a balenced connection. The output stage is designed to provide a balenced output. THis is not affected by the input to the BFD, which can be either balenced or unbalenced. A simple RCA unbalenced out from AVR to a 1/4" phone plug or an appropriately wired XLR connector (more reliable connection IME) works fine especially if it is a short cable run.


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## Otto (May 18, 2006)

Sonnie said:


> I'm not all that familiar with balanced inputs and outputs, but that sounds like a plan to me. So all I really need is XLR cables. :scratch:


That's right. You'll need one balanced cable per channel that you want to run. There's nothing magical about them... Just another wire inside the cable and cool looking connectors. You can easily get them at bluejeanscable as well as guitar center. I bought five one-meter balanced cables from a guy on eBay who is a retired EE tech and now sells stuff like that... 



> I wonder though... from my Yamaha receiver to the BFD will not be balanced, so will the connection from the BFD to the CX to the EP still be balanced?


I've wondered about that, but bobgpsr said it'll convert your singled-ended to balanced, so it should be no problem. It should be easy for them to do the conversion, so it makes sense.


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## Sonnie (Apr 11, 2006)

I had Bluejeans build my last ones so I'll probably have them build me a few more, except go with the balanced where ever possible this time.










The only thing I'm not sure about is if the EP2500 will accept one input and output to both channels. (EDIT: Just read the manual and Parallel Mode will take care of this for me.)


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## Wayne A. Pflughaupt (Apr 13, 2006)

Sonnie,

I’ve used unbalanced runs that were over a hundred feet with no noise problems. Noise won’t be an issue as long as you use a quality cable with a good shield. Even with cheap cable, noise would only be an issue if you ran it near something that would induce noise into it. 

Re the RCA to XLR cable for the receiver to BFD and BFD to SVS subs, there’s no compelling reason to use XLRs there. If Bluejeans will do RCA to 1/ 4” cheaper, go with that. You’ll still get the balanced output from the BFD for the signal run to the new sub.

Regards,
Wayne


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## basementjack (Sep 18, 2006)

Wow, this looks like a cool project - I wish you were closer to Chicago!


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## Sonnie (Apr 11, 2006)

Chicago ain't that far Jack... it would be a good road trip. Wayne and I have visited each other at about 11-12 hours apart.

Wayne, good point on the 1/4" connections.... I'm sure they will be cheaper. For those to be balanced they need to be stereo connectors, right?


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## Otto (May 18, 2006)

Sonnie said:


> For those to be balanced they need to be stereo connectors, right?


Yep.


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## Sonnie (Apr 11, 2006)

From the Receiver to the BFD (1/4" to 2 RCA)... that 1/4" will be mono. From the BFD 1/4" out to the pair of SVS subs RCA, the 1/4" there will be mono.

All 1/4" to 1/4" will be stereo.


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## Wayne A. Pflughaupt (Apr 13, 2006)

Probably should have clarified, it will (probably) be cheaper to substitute the XLRs for 1/4” mono plugs for the unbalanced. Might be another story for the TRS 1/4”, though. Those things can often cost 2-3 times the price of the mono 1/4” plug, so XLR there might actually be cheaper. Check their prices before you order!

Regards,
Wayne


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## Otto (May 18, 2006)

Sonnie said:


> From the Receiver to the BFD (1/4" to 2 RCA)


Wouldn't that be one RCA coming from your receiver's sub out, then going to two 1/4" monos to each channel of the BFD?



> all 1/4" to 1/4" will be stereo.


I know the signalling is the same, but I always like the XLR ends...

And I certainly don't mean to give you a hard time, and I know what you mean, and I'm being a bit picky, but they would only be "stereo" if they were employed in a system that was sending a stereo signal. I guess I'd say that the ends are 1/4" TRS (tip-ring-sleeve). The "mono" connectors are 1/4" TS... Yeah, a bit nit-picky... :bigsmile:


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## Sonnie (Apr 11, 2006)

Yeah, I got that backwards... RCA to 2 x 1/4" from the receiver to the BFD.


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## Sonnie (Apr 11, 2006)

Rut-wro

bluejeancables pricing:

$58 - 30' balanced cable (XLR or TRS)
$25 - 3' balanced cable
$38 - 3' RCA to dual TS unbalanced
$47 - 8' TS unbalanced to dual RCA 
$168

I think that's a little much on the 3' and 30' balanced cables.

I found this 30' balanced at Sweetwater for $30. They have a 2' balanced cable for about $20. That's $50 shipped vs. $83 from bluejeancables.com I may be stuck paying out the wazoo on the dual cables. I think I paid less last time... like $35 vs. $47 for that 8', except on is only 5' instead of 8'.

Anyone got any ideas on what I should do here. I really don't want to use adapters on the dual split cables.


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## Sonnie (Apr 11, 2006)

proaudiosolutions.com had a 30' HOSA 1/4" TRS and a 3' for $28 shipped. If their shipping wasn't $12 that would be a pretty good deal on those.


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## Wayne A. Pflughaupt (Apr 13, 2006)

Take a pass on those. HOSA uses cheap cable and connectors.

Who’s your pal and buddy?  If you really want to save some money, I can do them for you. I recently made some cables for my computer system for under $60, using Canare cable and Neutrik RCAs.

Regards,
Wayne A. Pflughaupt


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## Wayne A. Pflughaupt (Apr 13, 2006)

Using the same or similar parts that I did: 

Canare mini-mic cable (low profile cable is necessary for the splitter cables) - $15 and change.

TRS plug - $10 for four.

Mono plug - $6 and change for three.

Dayton Super RCA (has extra-large opening to accept two of the Canare mini-cables for the splitter) - $1.90.

Neutrik RCA (for the non-splitter connections – I prefer this one to the Dayton, but it can’t be used for a splitter) - $3 and change for two.

~ $38, plus shipping, which will probably double the price. Can you afford that? 

Regards,
Wayne


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## Sonnie (Apr 11, 2006)

I'm all over it, but I will need them probably within the 2 weeks. I'm trying to think how much more time we are gonna need to finish the behemoth. I think we will be done in 2 weeks or less though. 

Would that be putting too much pressure on you... :bigsmile:

I would want to toss you some extra for your time... and I don't want any argument about it.


On the 2 balanced cables the ideal length would be 32' on the long run and 18" should handle the short one since it's from the crossover to the amp and they will be stacked on top of each other in the back of the room. I'm probably going put them on a small stand back there. And on the 32' run, is the mini mic cable okay to use? It would be good because I can simply tuck it up under the baseboard, but if it needs to be thicker that would be okay too, I can probably still get it tucked in, it will just be a little more challenging.


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## bobgpsr (Apr 20, 2006)

Wayne A. Pflughaupt said:


> ...there’s no compelling reason to use XLRs there. If Bluejeans will do RCA to 1/ 4” cheaper, go with that.


I have had problems with the BFD and simple mono (TS only) 1/4" phone plugs into/out of my BFD. If they get slightly bumped just so -- I get a thunderous hum from my PC-Ultra sub. Just not happy with the quality/reliability of the phone plug connections, whereas the XLR connection is rock solid.


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## Wayne A. Pflughaupt (Apr 13, 2006)

Sonnie said:


> I'm all over it, but I will need them probably within the 2 weeks.


Hmm, two weeks, dunno. At least half that or more would be lost to the shipping time...

I should revise my post about the Hosa cables – I was muddling my pro-audio and home audio worlds. :dizzy: It’s their XLRs that are cheap (I’d forgotten you were going with TRS). Their 1/4” connectors are fine for what you’re doing. Yes, their cable is cheap, and I would hesitate to use it for mains, but this is for subs after all, so it will be fine. So – that quote from proaudiosolutions looks pretty good.

Since you’re considering the “cheap” route, might as well just look into using splitters and “y” adapters. From an electrical standpoint a split is a split, no matter how it’s done. The only advantage custom “y” cables offer is a more physically robust connection – i.e, one that can’t be separated like you get with three separate ables connected with a “y” adapter. But home theater installations aren’t particularly demanding – once stuff is set up it doesn’t get messed with unless you go in to re-do things.

The mini mic cable is good for any audio use. For what you’re talking about, running it around a baseboard and stuffing down into the carpet, I have a spool of stuff on hand that’s even thinner – about as thin as those cables that come in the box with components. Works great, really "tuckable." :laugh: You could also use some installation-grade cable. It’s typically is very slim, with a thin jacket and foil shield. The premise is that once installed, it won’t be subjected to any abuse, so there’s no need for thick jacketing.

Actually, the stuff we usually use for HT - at least for audio - there’s no good reason for it to be as thick as it is. Typically the extra size comes from thicker jackets. That’s great to have say, on a stage, where cables get stepped on and heavy things fall on them, but for home audio it’s really overkill and really only serves to add to our perennial cable clutter problems (in a rack at least).

Regards,
Wayne


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## JCD (Apr 20, 2006)

OK, I admit I didn't read every post, only part of it.. but I thought I'd throw something in to the mix anyway.

I would think having the amp as close to the sub as possible is the best solution regardless of balanced or unbalanced cables. I've been led to believe that a line level signal on a long connection was OK, but running speaker wire that long would actually decrease the final DB of your sub/speaker/etc.

Don't ask me to prove it or point you to where I read/saw that.. it's just something I've got in my collective unconscious.

JCD


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## bobgpsr (Apr 20, 2006)

JCD said:


> I've been led to believe that a line level signal on a long connection was OK, but running speaker wire that long would actually decrease the final DB of your sub/speaker/etc.


A common term for it is IR loss (from the IR = V electrical formula). Any speaker cable resistance times large amperage (for high power subwoofer drivers) results in voltage drop. Really more like power lost to heating up the cables. That is why many use huge gauge speaker cables like #12 or even #10 or double up cables. Easier to just colocate the sub power amp near the sub and have short speaker wire runs so the IR loss is not as bad. Balanced cables with true balanced source and sink are very good at resisting hum pickup.


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## Wayne A. Pflughaupt (Apr 13, 2006)

So – what’s the verdict, Sonnie? 

Regards,
Wayne


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## Sonnie (Apr 11, 2006)

Well, I still need the cables and I've wasted a few days I suppose. How quick can you get them made up once you get the items in hand?


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## Sonnie (Apr 11, 2006)

Actually, I'll go ahead and order what you need and have it sent to you, except for the balanced cables. I'll go ahead an order those from above and use some adapters and splitters until you get mine made up.


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## Sonnie (Apr 11, 2006)

One more thing... PE is out of the Neutrik RCAs.


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## Wayne A. Pflughaupt (Apr 13, 2006)

I could get them done the following weekend at the latest. 

If you want to do this, get with me before you order, especially if you want a really thin cable for that long run. I have some installation-grade stuff on hand here that’s even thinner than the Canare mic cable – just need to make sure I have enough of it, and that it’s balanced. I also have the RCA that will accommodate the split, so you wouldn’t have to order that either. We’ll also need to change one of the 1/4” mono plugs I recommended, the one doing the split, for one with a big enough opening in the barrel for the two cables.

Also, since this is a subwoofer signal chain, there’s no good reason to use stick with gold plating. Switching to nickel 1/4- inchers might save a few more bucks.

The Neutrik RCA is alwo available with white, red and yellow identification bands - you can sub for any of those.
http://www.partsexpress.com/webpage.cfm?WebPage_ID=3

Regards,
Wayne


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## Sonnie (Apr 11, 2006)

It's not a big hurry really because I'll use temp connectors, adapters, etc. until you get it all built. But all I'll need is the Y adapter ones, since I'm gonna just buy the balanced cables, 30' and 1-2'.


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## Wayne A. Pflughaupt (Apr 13, 2006)

In that case, I have the RCA connector for the RCA-to-1/4” split, so don’t order that. I also have a mono 1/4” plug for the 1/4”-to- RCA split, if you don’t mind nickel-plated. If you really want gold, I’m not sure the barrel of the one I linked before has a big enough opening to accept both mic cables, as I’ve never used it myself. So you’ll need to sub this PE number with the one I linked earlier:
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=091-1170

Unfortunately, it only comes in a pair. 

Re your Markertek order:


> bluejeancables pricing:
> 
> $38 - 3' RCA to dual TS unbalanced
> $47 - 8' TS unbalanced to dual RCA
> $168


You’ll need 22 ft. of the cable, double the amount you calculated here.

Also, on your Markertek order, would you mind ordering me a 75-ohm Canare RCA? I’ve been wanting to take a look at one, but I forgot about it when I made my last Markertek order.
http://www.markertek.com/SearchProduct.asp?item=RCAP-C5A&off=4&sort=prod

Thanks!

By the way, the color indicator band on the Neutrik RCAs looks to me like a little ring of heat shrink. It would be easy to remove, so there's no need to wait for them to get the black ones in.

Regards,
Wayne


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## Sonnie (Apr 11, 2006)

You can use the nickel RCAs... I have no problem with that. I'll just pay you for them, or I can re-order for you either one.

So all I need to order is the cable and the Canare RCA for you.

Can you give me specific part numbers... neither of your Markertek links go to the products you mentioned... I've tried to link to the products too, but it always pulls up something else. They got one of those funky websites.


Is this the right Canare RCA you want? Canare RCA Type Crimp Plugs For 75 Ohm Coax Part Number RCAP-C3A

There are several part numbers depending on the cable you are using.



And this mini mic cable? Canare L-2E5 Mini Microphone Cable Part Number L-2E5


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## Wayne A. Pflughaupt (Apr 13, 2006)

Hmm, don’t know what’s up with that... Yes, the mini-mic cable is L-2E5 (need 22 ft. of it). The RCA is RCAP-C5A. Probably no functional difference, but I wanted the same one Chris White recommends on his DIY cable page, and the C5A is the one I saw there.

I guess this has all gotten a little befuddled, so here’s what else we need, from Parts Express:


2 ea. Dayton Mono 1/4” Phone Plug #QMPG - $2.05 ea. 
2 ea. Neutrik RCA # NYS373 (black). If they’re out of that one, you can subsitute NYS373-R, NYS373-WT or NYS373-Y.

That’s about it, since you’re ordering the long balanced cables elsewhere.

Don’t worry about paying for the connectors I have. The 1/4” I found free at a job site recently. The Super RCA (for the split) is just taking up space in my parts bin; I think it’s leftover from some project our church needed years ago, I don’t even remember. I’ve never used that particular kind myself, so I know it’s nothing I bought and paid for.

Regards,
Wayne


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## Sonnie (Apr 11, 2006)

One more thing on the cable.

I noticed they have the Belden BL-1855A for about the same price, actually a few cents less, but it's a little thicker wire (23ga vs. 26ga) and appears to be a little better quality and better built than the L-2E5.

Belden BL-1855A:
* Number of Coax: 1
* RG Type: Sub-miniature 59/U
* AWG: 23
* Stranding: Solid
* Conductor Material: BC - Bare Copper
* Insulation Material: Gas-injected FHDPE - Foam High Density Polyethylene
* Outer Shield Material Trade Name: Duofoil
* Outer Shield Material: Dual Shield - Duofoil/TC - Tinned Copper
* Outer Jacket Material: PVC - Polyvinyl Chloride
* Plenum (Y/N): N
* Nom. Characteristic Impedance: 75 +/- 1.5O 

L-2E5:
# Gage/Strand: 26
# Number Of Pairs: 1
# O.D: .181
# Shield: 96% Braided
# Jacket PVC 

This is what bluejeancables used on my last splits. What do you think?


Nevermind... I just sent both to you and you can use whichever you think better, keep the other for good times.


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## Sonnie (Apr 11, 2006)

Everything is ordered and on it's way to you. Markerteck is UPS and PE is U.S. Mail.


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## Wayne A. Pflughaupt (Apr 13, 2006)

Okay, we’ll see when it all gets here. Coax is a different animal from mic cable, though. Since the center conductor is solid it’ll be stiffer than the Canare – may or may not make a difference in your install. And, although the Canare is 26 gauge, it has two conductors, which I was going to tie together – i.e., 23 ga. total.

It’ll come down to which is thinner – any thicker than the Canare and I won’t be able to get two of them into the connectors for the splitters. Still, it’ll be interesting to see the Beldon first hand. Always heard good stuff about their RG-59.

Regards,
Wayne


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