The Dynaco Tube Audio Forum

Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Dynaco VTA tube amp kits, all Tubes4hifi.com products and all Dynakitparts.com products


    Found a use for my tape out switch

    Share
    avatar
    vtshopdog

    Posts : 104
    Join date : 2015-07-11
    Location : UT, USA

    Found a use for my tape out switch

    Post by vtshopdog on Fri Nov 04, 2016 2:30 pm

    We listen to radio 2 or 3 hours most mornings and there is no need to have consumable tube gear running 15-20 hours a week for this.  I did a rebuild on my SP-12 last spring and rewired the tape out switch as an A/B splitter output downstream of my selector switch to allow access to all sources without firing up the tube gear.

    So it pretty much goes like so:

    All component RCA inputs connected to SP-12 selector switch
    SP-12 selector to Tape switch

    Tape switch "source" position goes on to volume controls, SP-12 board and on to M125's and main system - stock configuration.
    Tape switch "tape out" position goes to back panel "Tape Out" RCA's and on to a small passive preamp (built from Tube Cad A3 stepped attenuator PCB kit) and on to another small power amp and separate small affordable speakers.

    What this allows is I can now listen to all sources without firing up the tube pre (save phono).  Since the passive pre attenuators end up grounding into the SP-12 I was worried about creating ground loops in this mess of possible switch modes, but no issue and probably more dumb luck than any sort of savvy - (I'll take it when it comes my way)


    Added a couple photos in an edit today.


    avatar
    tubes4hifi
    Admin

    Posts : 1373
    Join date : 2008-11-30

    Re: Found a use for my tape out switch

    Post by tubes4hifi on Tue Nov 08, 2016 3:55 pm

    VT,
    very smart use of the tape monitor switch!!
    this is almost identical info I give to people who want a "Home Theater Bypass" switch to their expensive/fancy home theater 7.2 receiver.
    avatar
    vtshopdog

    Posts : 104
    Join date : 2015-07-11
    Location : UT, USA

    Re: Found a use for my tape out switch

    Post by vtshopdog on Tue Nov 15, 2016 8:52 pm

    Ha - I'm not surprised, but "small affordable speakers" placed on the floor tucked against wall in a very sub-optimal location sound, well, pretty bad, even just for listening to NPR in the morning.  

    No "sweet spot" in this setup ...

    Sponsored content

    Re: Found a use for my tape out switch

    Post by Sponsored content


      Current date/time is Thu Nov 23, 2017 5:02 am