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    SP12/PH12 Phase Correct?

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    kevco

    Posts : 70
    Join date : 2009-07-16
    Location : Aldan, PA, USA

    SP12/PH12 Phase Correct?

    Post by kevco on Tue Jun 28, 2016 5:30 pm

    Anybody know if the SP12 line stage is phase correct or inverting? I assume the PH12 is phase correct at the tape output, how about at the preamp outputs?
    Thanks all....

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: SP12/PH12 Phase Correct?

    Post by tubes4hifi on Sat Jul 02, 2016 1:33 pm

    both the SP12 and PH12 are phase correct, as each one uses two stages

    kevco

    Posts : 70
    Join date : 2009-07-16
    Location : Aldan, PA, USA

    Re: SP12/PH12 Phase Correct?

    Post by kevco on Sat Jul 02, 2016 2:39 pm

    Thanks Roy, that's what I needed to know.

    WntrMute2

    Posts : 101
    Join date : 2010-11-21

    Re: SP12/PH12 Phase Correct?

    Post by WntrMute2 on Sun Jul 03, 2016 8:02 pm

    My SP14 (built by Don Sachs) seems to invert phase at least when measured with the android polarity checker app.  I have two other preamps and know that one inverts phase and one does not.  The polarity measurements seem correct for those 2 and the SP 14 measures the way as the inverted one does.  Does this make sense to you Roy?

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: SP12/PH12 Phase Correct?

    Post by tubes4hifi on Mon Jul 04, 2016 3:25 am

    OK, so maybe I'm wrong, I don't have a polarity checker, guess I need to hook up my dual trace scope to it sometime and see . . .
    Any time you have a phase reversal, you can correct it by reversing the speaker leads to the amplifier.

    WntrMute2

    Posts : 101
    Join date : 2010-11-21

    Re: SP12/PH12 Phase Correct?

    Post by WntrMute2 on Mon Jul 04, 2016 7:42 am

    The app is free and easy to use.  Just plug a long headphone to rca cable into the input and start the app.  The clicks register as either red or green.  Simple as that.




    Last edited by WntrMute2 on Mon Jul 04, 2016 7:50 am; edited 1 time in total (Reason for editing : Tried to add pics to see if I could do that.)

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