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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
russ69's avatar
russ69
3,519 posts
 
"Y" off a single pair of outputs. 
cathy062 OP
15 posts
 
Tried it, same problem.
fuzztone's avatar
fuzztone
5,629 posts
 
I’ve been splitting line outs for years no problem.
When I upgraded the pre I hooked it up customarily. It sounded slightly distorted compared to the old. Some upgrade!
Then I un Y’d. Problem gone.
For your situation I would try converting the sub feed to unbalanced and run it through an isolation transformer before any active stages.
Or try the IsoMax immediately after the Athena.
russ69's avatar
russ69
3,519 posts
 
Did you try the RCA outputs? 
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cleeds
5,959 posts
 
I’m not familiar with your exact components, but most preamp outputs are wired in parallel. That means the preamp now has to drive the lower combined impedance of the two amplifiers. That could be an issue, especially if your preamplifier’s output impedance is high. Although the exact number is debatable, manufacturers typically recommend that the preamp see an impedance from the amplifier(s) that is 10x greater (or more) than the preamp output impedance.
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