Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Guitars => Topic started by: dpm309 on October 23, 2024, 12:20:47 pm

Title: Balanced XLR Output
Post by: dpm309 on October 23, 2024, 12:20:47 pm

I want to add a balanced XLR balanced output to a bass guitar. I have attached the schematic I came up with using a Jensen JT-DP-E direct box transformer. Will this work? Also, is the 6.8k resistor needed?Thanks

Title: Re: Balanced XLR Output
Post by: acheld on October 24, 2024, 04:01:50 pm

Quote

Will this work? Also, is the 6.8k resistor needed?

It should work. It was designed for this purpose.  The frequency response supports using it for a bass.

I've enclosed a schematic for the "typical application."   This includes the 6.8k resistor as well as R2 and C1, which are intended to "lift" the ground.

I believe, but am not sure, that the 6.8k resistor assists in rejecting extraneous RF signals.  While you could certainly try to use the unit "bare bones" as you do in your layout diagram, I'd suggest using it as designed.  Including the ground lift and the switch to take it in or out of circuit.

Curious as to why you need a balanced signal for a bass . . .  And why not just buy a pre-configured box to do  the job as opposed to purchasing a component and wiring it up?

Title: Re: Balanced XLR Output
Post by: dpm309 on October 24, 2024, 04:46:40 pm

Thanks for the schematic. This is for a bass guitar that a friend of mine is building and he wants both 1/4" and balanced XLR outputs similar to an old WalBass or Hohner,  My drawing was based on the Hohner B2a fl. They did not have a ground lift. Neither did the old Walbass'.

Title: Re: Balanced XLR Output
Post by: dpm309 on February 26, 2026, 12:38:37 pm

OK, the Jensen or Hammond transformer will not fit into the bass guitar cavity. I have come across a Triad TY-1402-P-B that will fit and was wondering if this would work. I have attached the datasheet. I can't find any info or wiring diagram using the Triad. https://catalog.triadmagnetics.com/Asset/TY-142P.pdf
Thanks, Dan

Title: Re: Balanced XLR Output
Post by: shooter on February 26, 2026, 03:16:38 pm

should work at least for testing
the 200hz low end might shave some of the bass from the bass

Title: Re: Balanced XLR Output
Post by: dpm309 on February 27, 2026, 10:51:53 am

Thanks Shooter, I'll give it a try. This cost a lot less than the Hammond/Jensen tranny. Am trying to find out a pinout diagram for the Triad.

Title: Re: Balanced XLR Output
Post by: shooter on February 27, 2026, 01:43:23 pm

Quote

Am trying to find out a pinout diagram for the Triad.

??


the datasheet has a pinout

Title: Re: Balanced XLR Output
Post by: dpm309 on February 28, 2026, 10:12:22 am

Can I assume that the pinout is the same as the Jensen/Hammond trannies? I am trying to figure out how to wire it into the XLR circuit you posted earlier. Left side primary, right side secondary?

Title: Re: Balanced XLR Output
Post by: shooter on February 28, 2026, 12:27:28 pm

look at the triad document, pins 1 2 3 are primary

Title: Re: Balanced XLR Output
Post by: dpm309 on February 28, 2026, 03:29:53 pm

Shooter, Got it.Thanks,