SE to Balanced Line Converters

I am looking for a commercial single ended to balanced line out converter or preamp stage. Pre-made units boxed and ready to go don’t seem to be readily available. It seems like a basic thing but not sure why something for say $40 from Behringer or similar doesn’t immediately come up on a search. However, a $10 Sparkfun THAT1646 breakout board with TRS jack did come up. If anyone has suggestions for a commercially made ready to use one, please share here:

Sparkfun THAT1646 breakout board:
https://www.digikey.com/products/en?mpart=BOB-14003&v=1568

Needs a +/-voltage PSU and a panel jack.

I have made simple 2 transistor converters using a CFP in SE Class A and that works well but looking for an ultra low distortion IC implementation here.
 
MAAC0,
Thanks for that tip - this was exactly what I was looking for. Don’t know why a google search could not turn up something like this. $55 is a great price too. Only thing is the -88dB noise floor. Most of my stuff is -125dB noise floor - but it will do until I make a custom one.

Manual even has a schematic:
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Gofar99, thanks for the tip but I want to avoid transformers for the extra 3rd harmonic they can add.

Russo,
Thanks for the tip on the Mesa Boogie clearlink - but I think the Rolls unit is closer to what I was looking for.
 

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not to mention that if this is to be considered standard practice, that in order to maintain true galvanic isolation that no circuit ground should be connected to chassis.
That's the exact opposite of 'good engineering practice'.
If you want galvanic isolation use an audio input or output transformer, but still connect the circuit ground to the chassis.
 
I made a +/-15v power supply from a +/-24v DC-DC converter and LM7815/7915 voltage regulators to power the Sparkfun THAT1646 SE to Balanced drivers. Connected it to my TPA3255 Reference Class D amp with balanced inputs. Now I can use SE headphone outputs to drive the TPA3255 rather than always having to rely on the balanced output section of the Focsusrite. These Sparkfun breakout boards are very convenient and sound great.

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astromo

Member
2017-11-13 11:17 am
BFN
Handy piece of hardware you've turned up xrk. I'm filing that one away as a mental note for future. Thanks for the tip.

MAAC0,
Thanks for that tip - this was exactly what I was looking for. Don’t know why a google search could not turn up something like this. $55 is a great price too. Only thing is the -88dB noise floor. Most of my stuff is -125dB noise floor - but it will do until I make a custom one.


Interested to see what you come up with as a follow on.
 

astromo

Member
2017-11-13 11:17 am
BFN
Cool. I'll keep my eye on where this ends up.

What's your thinking behind the selectable gain?

Is that to give an SE input signal a boost, so that a user can level things up if they switch across from a Balanced input?

Or just for general flexibility?

If the former, I suppose a selection switch could be rigged up without too much difficulty?
 

astromo

Member
2017-11-13 11:17 am
BFN