TRS cable vs TS in the L2k

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TRS cable vs TS in the L2k

Postby Basscase » Sat Apr 01, 2017 9:55 pm

This is a curiosity query.
I accidentally bought a TRS cable, thinking it was a standard instrument (TS) cable. :roll:
When I plugged it into my L-2000, it only worked in passive mode, I assumed that my battery had died, which surprised me, because the battery usually dies slowly, not all of a sudden. That's when I noticed the cable had an extra ring. So then I tried a regular cable and the active mode was working again.
Anyway, just curious if anyone can explain why the L2K only works in passive mode with a TRS cable, and if it will harm the electronics in any way if I use it?

I did a little research, and found that a TRS cable has an extra ring and can be used for a stereo signal or a balanced signal. Copied below is from the Sweetwater website.

Common Cable Connectors Explained
"In the audio world, there are six common cable connectors you’ll come across frequently: TRS and XLR for balanced connections and TS, RCA, SpeakON, and banana plugs for unbalanced connections.
TRS is the abbreviation for “Tip, Ring, Sleeve.” It looks like a standard 1/4″ or 1/8″ plug but with an extra “ring” on its shaft. TRS cables have two conductors plus a ground (shield). They are commonly used to connect balanced equipment or for running both left and right mono signals to stereo headphones. You will also find TRS connectors on the stem of Y cables. These are used for mixer insert jacks where the signal is sent out through one wire and comes back in through the other."
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Re: TRS cable vs TS in the L2k

Postby Ken Baker » Sun Apr 02, 2017 9:38 am

Basscase wrote:This is a curiosity query.
I accidentally bought a TRS cable, thinking it was a standard instrument (TS) cable. :roll:
When I plugged it into my L-2000, it only worked in passive mode, I assumed that my battery had died, which surprised me, because the battery usually dies slowly, not all of a sudden. That's when I noticed the cable had an extra ring. So then I tried a regular cable and the active mode was working again.
Anyway, just curious if anyone can explain why the L2K only works in passive mode with a TRS cable, and if it will harm the electronics in any way if I use it?


Your active bass has a Tip-Ring-Sleeve (TRS) jack. In the bass the Ring connection connects to battery-negative, and for active mode to work this Ring connection needs to connect to ground. When you plug a regular Tip-Sleeve plug into a TRS jack, the jack's Ring connection contacts the plug's Sleeve which provides that ground connection for battery-negative. This powers up the onboard preamp and your active mode works.

TL;DR... A regular mono cable plugged into your bass acts as a switch to turn on the preamp. A TRS cable will not do this.

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Re: TRS cable vs TS in the L2k

Postby Basscase » Sun Apr 02, 2017 9:17 pm

Thank you Ken.
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Re: TRS cable vs TS in the L2k

Postby Ezn73 » Fri Apr 26, 2019 4:21 pm

There's the EMG ES-918 that powers active basses with a TRS cable. The description says it's an external power supply for EMG pickups, but then it is a little vague and implies it can supply any active instrument.

I am curious about this, but (full disclaimer) I have no idea if it will work with G&L active instruments.

I do have a Fender MIJ fretless Jazz Bass that I dropped EMGs into, so it would be awesome if it worked with that and my L-2500.
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Re: TRS cable vs TS in the L2k

Postby Ken Baker » Fri Apr 26, 2019 7:24 pm

Ezn73 wrote:There's the EMG ES-918 that powers active basses with a TRS cable. The description says it's an external power supply for EMG pickups, but then it is a little vague and implies it can supply any active instrument.


I've read articles where people have modified their amplifier and instrument so that the amp provides power to the instrument through the ring of a TRS cable. All to avoid having to replace batteries. This all sounds wonderful until someone not familiar with the setup plugs in a regular TS cable and shorts the power supply to ground. It's also limiting in that those modified basses will only work with the modified amp.

I am curious about this, but (full disclaimer) I have no idea if it will work with G&L active instruments.


A G&L bass could be modified to do that, but I'd really wonder why. To save on batteries that last months?

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