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Signal Degradation Balanced Output

Has anyone developed a workaround that solves signal degradation when splitting. The problem that I have occurs even when the preamplifier has two balanced outputs.

Years ago I became aware of this problem when using my Sonic Frontiers Line 3, which has 2 pairs of balanced outputs, to drive a Theta Dreadnaught amp and a pair of Entec LF-20 subs. I thought the sound was excellent until oneday, I disconnected the cable to the sub and that’s when I heard what I had been missing from the Wilson Cub I, transparency and reverb that allows you to hear deep into the music.

Now, I’m running Focal Mini Utopia Be, Denafrips T+ DAC to Athena Pre, which has 2 pairs of balanced outputs driving a ARC VT-130 and a Focal Sub6. Same problem! I’ve tried inserting my Jeff Rowland Model 112, then tapping off the speaker terminals with a Jensen ISOMAX transformer which then goes to sub.. the problem persists.

The problem isn’t huge, it’s just that the higher the resolution of the components, the more noticable it is. My setup needs the lower fundamentals that a sub brings, but at a cost I’m not happy with.

Any ideas?




cathy062

Showing 3 responses by georgehifi

georgehifi's avatar
georgehifi
10,312 posts
 
cathy062 OP14 posts09-06-2021 10:45amIt sounds like there is no workaround to the problem, however.

You could use a SS low gain low output impedance SS buffer after the SF3 to drive everything via Y connectors from it’s output.

EG:
See if this guy still has this
https://www.usaudiomart.com/details/649322907-burson-audio-buffer/

Or this dual input one
https://www.ukaudiomart.com/details/649605507-burson-ab160-solid-state-buffer/

or
https://www.stereonet.com/forums/topic/253123-sold-fs-trade-in-burson-audio-ab160-audio-buffer-rca/

Cheers George
georgehifi's avatar
georgehifi
10,312 posts
 
 Would the same thing be the cause here as well?
Yes, your at best halving the load impedance seen by the dac they would come back to the same dac buffer/s only depending how it's configured one could have the load of the rca and 1/2 of the xlr on it, the other the other half of the xlr, so it's load sharing could be bit lopsided also.

Best to use all from the RCA output or all from the XLR output and hope that either will have enough low impedance drive to handle the parallel load impedance of what your driving into.

Cheers George    
georgehifi's avatar
georgehifi
10,312 posts
 


cathy062 OP
Has anyone developed a workaround that solves signal degradation when splitting. The problem that I have occurs even when the preamplifier has two balanced outputs.
Years ago I became aware of this problem when using my Sonic Frontiers Line 3
Trouble is when you drive into two amps from the SF3 output, those two amps present a much more difficult load to the SF3, and being tube it’s not as good as driving into low input (2 amps) as a solid state pre can.

EG:
Two amps both with 50kohm input each, the SF3 will then see 25kohm load.
Two amps one with 50kohm input the other with 25kohm input, the SF3 then sees 16.5kohm load
Tube preamps don’t like this kind of low impedance loading.

Cheers George
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