Douk Audio T8pro observation

[khaliss]

hi all,

I just wanted to point out an observation with the Douk Audio T8-pro, which I recently acquired to add to my system (refer to the diagram below). What I noticed is that when I calibrate my Marantz AVR using Audyssey... I get a warning that says "CAUTION! Speaker: Phase (Front L/R)"... this is with the T8pro connected in-line, as shown on the diagram below. I tested it both on unbalanced (RCA) & balanced (XLR) connection to the amplifier, same result/caution. When I remove the T8-pro from the setup, directly connecting the AVR Front L/R pre-outs to the power amplifier, I do NOT get the phase error... so this means, the T8pro is putting the audio feed out-of-phase with the AVR, correct? Wondering if other owners have the same experience, but then again I imagine not a lot of people here would have a similar setup as mine. Is it possible that my T8pro is bad?

I mean the system sounds pretty good... should I not worry about it & leave everything as is? Should I email Douk Audio about it? Any feedback from the more experienced & technical forum members appreciated =)

 

[AnalogSteph]

Is it possible that my T8pro is bad?

No. Just overall inverting. Reverse polarity on the front speaker wires to make up for it, and everything should be fine.

 

[DVDdoug]

so this means, the T8pro is putting the audio feed out-of-phase with the AVR, correct?

I would assume so (inverted polarity)... There is no "rule" that a device has to maintain polarity and sometimes an inverting circuit is more convenient to build.

I read something once that said there is a 50/50 chance of a recording (or any one track in a multitrack recording) being inverted during the recording & production process.

Since you have rear-surround channels with different polarity, the speaker connections of one or the other should be reversed.

 

[khaliss]

thanks for the feedback guys, I'll reverse all my surround speakers then, since I already spent a lot of time calibrating & phasing-in all the subs individually with each other & the front speakers

 

[khaliss]

all speakers now reversed... guess that takes care of that, right?

 

[Scrivs]

You just need to reverse the connections of either the T8 ONLY, oR, conversely, leave those be, and swap the remaining speaker connections. Your choice.

If "... all speakers now reversed..." your problem will follow, with the T8 still being out of phase/polarity. Swap the connections for the T8 only, since you've spent time integrating the front and subs

 

[khaliss]

You just need to reverse the connections of either the T8 ONLY, oR, conversely, leave those be, and swap the remaining speaker connections. Your choice.

If "... all speakers now reversed..." your problem will follow, with the T8 still being out of phase/polarity. Swap the connections for the T8 only, since you've spent time integrating the front and subs

that's what I meant... I left the two front/main speakers as is (originally reversed), & proceeded with reversing the rest of the speakers (side & rear surrounds)... so all speakers should now be in the same phase
-or-
do you mean something else when you say "reverse the T8 only", how would I do that since the T8 preamp/EQ device doesn't have a phase switch(?)

 

[khaliss]

I ended up reversing the Front L/R speakers, changed it last night... it'd be a hassle not to, whenever I have to minor changes to the setup & recalibrate AudysseyXT again LOL no more error/warning message!