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    SP9+PH6 Build

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    goddlediddles

    Posts : 19
    Join date : 2012-10-13
    Location : Kerry, Ireland

    SP9+PH6 Build

    Post by goddlediddles on Wed Dec 19, 2012 3:01 pm

    This is my SP9 with PH6 phono stage. I decided to build it with the tubes going out through the top of the 12" x 10" x 2" chassis in order to match my single-ended triode tube amp. My first impressions were that it had a superbly bright and clear top end with no drop-off at all at low bass (30 HZ) and everything in between just as good. Noise is not a problem in the SP9 section, being nearly on a par with my J-Fet all solid state preamp; as a matter of fact I have now switched to the SP9 as my preamp of choice. I am not yet in a position to evaluate the PH6 section as I do not own a phonograph, having changed over to CDs but I intend to start listening again to vinyls because I'm convinced that analogue beats digital hands down. I spent 40 years as a recording engineer so I reckon I can tell the difference. As the photos show, it's a tight squeeze getting everything into the smaller chassis and this wasn't helped by not having a suitable transformer; the one I used had multiple windings and it was by adding and subtracting voltages that I got the necessary values. The transformer is mounted on the top of the chassis because of the lack of space underneath and anyway this layout matches my power amp. I enclosed all the supply and transformer connections behind a shield as shown. The blue colored 7 turn winding on the outside of the transformer is to bring my filament AC supply up from 10.5 Volts to 12.5 by adding it in series with the original winding. (This is a simple task with a toroid if there's space in the core which is usually filled with a soft compound which can easily be drilled).

    The final 6 shots have been uploaded in high resolution to enable them to be enlarged.

    Overall satisfaction: 100%. Many thanks to Roy for his excellent service and follow-up comments. Here is a link to all the photos: http://godfreyryan.com/SP9.html




    hawaii.ken

    Posts : 157
    Join date : 2012-01-31

    Re: SP9+PH6 Build

    Post by hawaii.ken on Wed Dec 19, 2012 6:43 pm

    Kudos for an amazing build!

    DynakitParts
    Admin

    Posts : 181
    Join date : 2008-11-30

    Photos

    Post by DynakitParts on Thu Dec 20, 2012 9:40 pm


    Godfrey,
    I like the old #6 vise in the preamp build photos. Appears to have seen it's
    share of projects. I also took a quick visit to Wexford via your photo link. Noticed
    a few pub photos in the mix...I enjoy going to the pub (tavern) with friends around
    the holidays or anytime for that matter. Thanks for sharing this with us.

    Merry Christmas

    Kevin @ Dynakit

    goddlediddles

    Posts : 19
    Join date : 2012-10-13
    Location : Kerry, Ireland

    Re: SP9+PH6 Build

    Post by goddlediddles on Fri Dec 21, 2012 9:13 am

    Yes Kevin, the vise has been through a hard life and is still as good as the day I bought it. Striking a stick welder on its surface has left most of the marks. Glad to hear that you like pubs for a bit of crac, as we say in Ireland and Wexford has some of the best outside Dublin. Seasons greetings....Godfrey

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