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    Building a Phono preamp

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    wroman214

    Posts : 5
    Join date : 2012-03-23

    Building a Phono preamp

    Post by wroman214 on Mon Dec 31, 2012 12:36 pm

    Without much in the way of specs available I am trying to decide what phono preamp to build. I have had a Trancendent Sound GG and phono a few years back and what I have been able to surmise from searching posts that the phono stages here exhibit more of the good tube qualities (warmer). In looking at the PH10 it says warmer than the neutral PH12 but does not give gain. What is the gain of the PH10?
    The higher number phono's have output buffers so I imagine they have lower output impedance but can anyone give a spec here or say what is expected for input impedance for best results?

    What is required (voltage)for transformers for the different models? The PH10 is differnt requiring less B+ voltage?

    I am leaning to building a a 15 but trying to look at all options, I am sticking to MM cartridges at this time but my Soundsmith has pretty low output, are these stages still quiet at 55db gain?

    At the present time using a SS Soundsmith pre. It sounds pretty good on on my best LP's but looking for a more forgiving setup that does not highlight every wart and tick on my less than stellar records. A popular phono preamp that I am told that does this is the EAR 834P but I cannot spend that kind of money for what seems to be a very simple design. So that is why I am here? Any help greatly appreciated.
    Walt


    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: Building a Phono preamp

    Post by WntrMute2 on Sat Jan 05, 2013 8:32 pm

    I don't fully understand your question but I am very, very happy running the PhonoClone3 phono stage into my tube pre-amp and onto a tube amp system. There is also a VSPS phono stage for MM carts that sounds quite good also. Cost will run about $100 for the stage including the power supply you'll have to build. The system holds its own against many phono stages costing $1000 or more. The designer's site is here Rjm and there is a huge support forum on the DIY forum site. You won't be sorry.


    Last edited by WntrMute2 on Sun Jan 06, 2013 4:03 am; edited 1 time in total (Reason for editing : changed plus to including.)

    wroman214

    Posts : 5
    Join date : 2012-03-23

    Re: Building a Phono preamp

    Post by wroman214 on Sat Jan 05, 2013 10:57 pm

    What is a Phono Clone 3.
    My questions are can anyone give the output impedance of the PH10, PH15. What kind of load will they drive?

    I need to pick a transformer and will probably not go with a toroid because of their tendency of passing on some appliance noise in my house, been there. So...what voltage taps are needed for the different phono preamps?

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: Building a Phono preamp

    Post by WntrMute2 on Sun Jan 06, 2013 4:01 am

    If you click on the "RJM" in my first response, a link should open to a website explaining all.

    Tube Nube

    Posts : 603
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: Building a Phono preamp

    Post by Tube Nube on Tue Jan 08, 2013 9:31 pm

    I've had a couple of vta phonos, one built into my SP8 preamp, and another free standing. I think its a PH11...

    I cant give you the specific figures, but Roy's phonos match moving magnet level cartridge outputs, as is the usual standard. A high output MC will work, but a step up tranny will be needed for regular variety low out put moving coils.

    I also have a TS phono, btw. I don't believe it would hold a candle to Roy's current flagship phono... PH14 or is it PH15?

    If i recall correctly, his PH11 was competing against the TS phono... And his latest is vastly better.

    Much like the flagship vta pre amp is vastly better than earlier models.

    As long as Im rambling a bit, i also have the TS GG, and the vta SP14 pre amp, and the latter is so much better than the GG that it's sickening.

    Ambling back to your questions, yes, Roys phonos are warmer, tubier, with more robust bass compared to TS offerings

    wroman214

    Posts : 5
    Join date : 2012-03-23

    Re: Building a Phono preamp

    Post by wroman214 on Wed Jan 09, 2013 2:25 am

    Thanks for the reply.

    tubes4hifi
    Admin

    Posts : 1261
    Join date : 2008-11-30

    Re: Building a Phono preamp

    Post by tubes4hifi on Wed Jan 09, 2013 2:31 pm

    hello WROMAN214,
    you're probably asking about our Tubes4HiFi phono stages, and I think WntrMute was referring you to another different phono preamp which is simplier and less expensive.
    Output impedance is generally not a problem unless you are trying to use very long interconnects to a preamp or amplifier following the phono preamp. Our basic phono preamps (PH6 thru PH12) have no output buffer and are intended to be used with a line preamp in the same chassis, they have an output impedance around 1500 ohms which would go directly to a 50K or 100K volume control.
    Our PH14 and PH15 have an output buffer and thus output impedence around 600 ohms and could be used with a separate preamp or amp thru 3 to 6 foot interconnects with no problems. For more specific info or questions please contact me directly thru email on my website or thru PM on this website
    Roy
    www.tubes4hifi.com/pre11.htm

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