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    SP12/PH12 Phase Correct?

    kevco
    kevco

    Posts : 69
    Join date : 2009-07-16
    Location : Aldan, PA, USA

    SP12/PH12 Phase Correct? Empty 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
    tubes4hifi
    Admin

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    Join date : 2008-11-30

    SP12/PH12 Phase Correct? Empty 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
    kevco

    Posts : 69
    Join date : 2009-07-16
    Location : Aldan, PA, USA

    SP12/PH12 Phase Correct? Empty 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
    WntrMute2

    Posts : 115
    Join date : 2010-11-21

    SP12/PH12 Phase Correct? Empty 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
    tubes4hifi
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    SP12/PH12 Phase Correct? Empty 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
    WntrMute2

    Posts : 115
    Join date : 2010-11-21

    SP12/PH12 Phase Correct? Empty 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.
    SP12/PH12 Phase Correct? Screenshot_2016-07-04-07-30-49_zpsacvqpbt2

    SP12/PH12 Phase Correct? Screenshot_2016-07-04-07-31-14_zpscr31pgdw


    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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