• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Best connection from laptop to QSC-K12

Sturg

Sturg

Nov 29, 2013
140
39
pittsburgh
#1
Need a long (30-50 ft.) cable to connect these two. Coming out of the laptop is a 3.5mm mini-plug headphone output.
Going into the QSC I have the options of RCA phono plugs, a standard 1/4 inch male, or a balanced XLR male.
Which is the best, quietest, most secure, noise-free, way to connect?
 
#2


Since you’re starting with an unbalanced signal, there is no “best way.” RCA, XLR or 1/4” will get the same thing.

IMO the main issue with this is not the choice of connections, but the fact that your typical off-the-shelf 3.5 mm extension cables are light-duty crap and not really suited for use on a stage. I ended up making my own cable, with a 3.5 mm Canare plug on one end, a 1/4” female TRS jack on the other, and a 1/4” TRS insert splitter to get from the female jack into the sound system.

Regards,
Wayne A. Pflughaupt



Administrator, Pedulla Club #45
Administrator, Tobias Club #133
Fretless Club #943
Big Cabs Club #23
Pedulla Club #45



 
Last edited:
#3
actually wayne, the headphone jack on the laptop is actually a balanced TRS signal. what you might mean is line level??

if you are after a solution box of sorts, try a radial stagebug.
[Invalid or Expired Link Removed]

i personally like wayne have made my own cable, using neutrik 1/8" TRS right angle, to a dual 1/4" TS, using canare cable. i wouldn't wire to XLR so as to not risk blowing up my devices by connecting it to a sound console that has a global phantom power on it. which is a pretty common to come across. i know that you are plugging it into a system, just to the speaker direct, but it only takes that one time to plug it in and boom. (ive seen this a few times..lol)

also the DI box will prevent this as well.
 
#4
I use a Peavey USB-P to add an XLR output to a laptop for connecting to soundboard, speaker, whatever. It's basically a DI with ground lift and is absolutely noise free. Just add the XLR and USB cable (for some reason it doesn't come with one)

Amazon.com: Peavey USB Audio Interface: Musical Instruments
 
As an Amazon Associate, TalkBass may receive commissions from qualifying purchases made via links on this site.
#5


No, a headphone output is not a balanced signal. It uses the same type of connector as balanced TRS, but it isn’t balanced.

A balanced TRS signal is mono. The signal (+) is carried on the tip, the signal (-) is on the ring, and the signal ground is on the sleeve.

A headphone jack is unbalanced stereo, with (for example) the tip carrying the signal (R+) and ring carrying (L+), and the sleeve sharing signal (-) for both left and right.

I say “unbalanced stereo,” but technically that isn’t correct. Since it’s driving transducers (aka “speakers”), a headphone output is more equivalent to a speaker output of an amplifier.

Regards,
Wayne A. Pflughaupt


Administrator, Pedulla Club #45
Administrator, Tobias Club #133
Fretless Club #943
Big Cabs Club #23
Pedulla Club #45



 
Last edited:
#8
What are you doing with the PC?

35-50ft isn't going to be much of a problem for line level signal.
Balance of course could be better, just more professional.
Just about any audio interface, even the less than $100 have balanced out and can drive the QSC fine for hundreds of feet. An interface may also have better latency if that matters to you.

Of course you can also get little stereo mixers that take the output of a PC and convert it to balanced output.

The wirlwinds are better than most give them credit. Not much reason to get anything more expensive.
 

Latest posts

Top Bottom
Back