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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
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cleeds
5,947 posts
 
athy062
I’ve tried balanced, unbalanced, Y-splitters with cables and one piece metal RCA Y-splitters, even made ulp some splitters with Neotech 1002 cable and pure copper contacts... same problem.
Understood. Did you calculate the effective combined input impedance of the amplifiers? None of the other efforts you mention would affect that, and using unbalanced lines would actually make things worse if the amplifiers themselves are differentially balanced.
I eventually decided to try the ISOMAX, thinking the problem was in the impedance matching of the preamp and amplifier... dame problem.
What is Isomax??
cathy062 OP
15 posts
 
No, I have never tried calculating impedances.  Not even sure how to do that.  I remember a cable tv installer told me that a coaxial splitter causes a 6db loss to the signal when inserted.  I was thinking that something like that is going on here, but I'm not using a splitter anywhere, unless the 2 pairs of balanced outputs are internally split.  A few minutes ago I disconnected my Audio GD headphone amp from my Denafrips DAC.  I had it connected using the unbalanced RCA interface.  The same type of problem was happening there.  The sound immediately got more resolving simply by disconnecting the RCA cable. Denafrips says not to use the unbalanced  RCA when using balanced XLR -- not sure why however.  I know that all my source components are fully differential, including both amps.

As for the ISOMAX, I tried it in hopes of getting a line signal from the amp's output.  The thinking here was that it would be separated from the amp's input signal.  It didn't work either.  So, I disconnected the balanced input from the Jeff Rowland amp feeding the ISOMAX and the same thing happened, the sound transparency and reverb immediately improved.  The analog cabling is all Acoustic Zen Silver Ref II with Matrix Ref II on the sub.  This is where I'm at.

https://www.google.com/search?q=jensen+transformers+sp-2sx&oq=jensen+&aqs=chrome.0.69i59j69i...
pauly
1,012 posts
 
You could look into using an active crossover between your Athena and ARC&Focal. 



cathy062 OP
15 posts
 
Forgot to mention, the ISOMAX, though they sell it as transparent sound, it definitely is not.  So, I would never use it immediately after the preamp on a line level.  I was using it from the amp's output to be converted to a balanced line level that is then sent to the sub.  Same problem.
cathy062 OP
15 posts
 
@Paul, haven't tried that... but, that seems like jumping into the fire.  
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