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    Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

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    seeirwin

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    Join date : 2018-07-23

    Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by seeirwin on Mon Jul 23, 2018 11:05 pm

    Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!
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    peterh

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    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by peterh on Tue Jul 24, 2018 2:27 am

    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!
    Yes, you will get a source selector , not a negligible thing in itself but an asset.
    Plugging rca-connectors may cause loud sound that might damage your speakers ( or ears),
    and is not self-evident if someone else should use them.
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    Peter W.

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    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by Peter W. on Tue Jul 24, 2018 7:39 am

    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!


    On the use of a preamp to improve sound quality with VTA70

    Follow this thread for an exhaustive (and exhausting) discussion on the relative virtue of pre-amps.

    seeirwin

    Posts : 4
    Join date : 2018-07-23

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by seeirwin on Tue Jul 24, 2018 8:16 am

    Peter W. wrote:
    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!


    On the use of a preamp to improve sound quality with VTA70

    Follow this thread for an exhaustive (and exhausting) discussion on the relative virtue of pre-amps.

    Hi. Can you (or anyone else) provide a link to or the title of the thread you're referencing? Thanks!
    avatar
    peterh

    Posts : 1038
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by peterh on Tue Jul 24, 2018 8:21 am

    seeirwin wrote:
    Peter W. wrote:
    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!


    On the use of a preamp to improve sound quality with VTA70

    Follow this thread for an exhaustive (and exhausting) discussion on the relative virtue of pre-amps.

    Hi. Can you (or anyone else) provide a link to or the title of the thread you're referencing? Thanks!

    http://dynacotubeaudio.forumotion.com/t3782-on-the-use-of-a-preamp-to-improve-sound-quality-with-vta70

    seeirwin

    Posts : 4
    Join date : 2018-07-23

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by seeirwin on Tue Jul 24, 2018 8:29 am

    peterh wrote:
    seeirwin wrote:
    Peter W. wrote:
    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!


    On the use of a preamp to improve sound quality with VTA70

    Follow this thread for an exhaustive (and exhausting) discussion on the relative virtue of pre-amps.

    Hi. Can you (or anyone else) provide a link to or the title of the thread you're referencing? Thanks!

    http://dynacotubeaudio.forumotion.com/t3782-on-the-use-of-a-preamp-to-improve-sound-quality-with-vta70

    Thank you!

    seeirwin

    Posts : 4
    Join date : 2018-07-23

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by seeirwin on Tue Jul 24, 2018 9:00 am

    Peter W. wrote:
    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!


    On the use of a preamp to improve sound quality with VTA70

    Follow this thread for an exhaustive (and exhausting) discussion on the relative virtue of pre-amps.

    I did read that entire thread, PeterW. Thank you. I'm not familiar enough with tubes/circuit design/the PH-16 enough to know whether there is an amplification stage that would enable the type of dynamic range you mentioned in your organ symphony example, or whether it's really just getting the RIAA curve applied and the signal up to line level. If anyone wants to weigh in, I'd appreciate it!
    avatar
    Peter W.

    Posts : 924
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by Peter W. on Tue Jul 24, 2018 10:51 am

    I did read that entire thread, PeterW. Thank you. I'm not familiar enough with tubes/circuit design/the PH-16 enough to know whether there is an amplification stage that would enable the type of dynamic range you mentioned in your organ symphony example, or whether it's really just getting the RIAA curve applied and the signal up to line level. If anyone wants to weigh in, I'd appreciate it![/quote]

    First, the disclaimers:

    a) I am not familiar with the PH16 design, but I see no controls on it. With that in mind, I suspect that the unit delivers a line-level output from a conventional magnetic cartridge.
    b) I further suspect that the output is somewhere between 1.6 and 2V. I cannot find actual specifications on the VTA site.


    With that in mind, it is "just one more input" should you decide to use an active pre-amp. And the reasons for using such a device are more-or-less dependent on a whole bunch of 'other factors'. I am unashamedly in favor of active pre-amps. For what that is worth.
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    solderblob

    Posts : 43
    Join date : 2018-05-20
    Location : Placerville, California

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by solderblob on Wed Jul 25, 2018 10:58 am

    seeirwin wrote:Hello,

    As the title suggests, my setup is a turntable into a PH-16 into an ST-120 with the attenuator knob. Simple! Would there be any benefit to adding a preamp such as the VTA SP-14? Every now and again, I run a DAC into the ST-120 by just swapping the RCA cables, which I don't mind doing.

    Thanks in advance for your perspective!

    I asked essentially the identical question in the aforementioned thread.  I have no use for selectable inputs as I am phono-only.

    No clear answer, but it's probably system dependent -- cartridge output and speaker sensitivity would make a difference.

    I was hoping Roy would weigh-in; presumably he's had experience with both configurations...

    So how does your PH-16 sound?  I'm getting ready to buy the kit soon, I hope.

    dave
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    tubes4hifi
    Admin

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    Join date : 2008-11-30

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by tubes4hifi on Wed Jul 25, 2018 1:00 pm

    Dave (solderblob)
    in your particular case I don't see any advantage of having a preamp, your PH16 is doing all the gain and impedance matching you need.
    You could add a small passive box with a switch, but I'm sure you're smart enough to turn off your amp when switching sources anyway.
    In 99.4% of cases, I agree with PeterW on active preamps (I am unashamedly in favor of active pre-amps).
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    solderblob

    Posts : 43
    Join date : 2018-05-20
    Location : Placerville, California

    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by solderblob on Wed Jul 25, 2018 1:19 pm

    tubes4hifi wrote:Dave (solderblob)
    in your particular case I don't see any advantage of having a preamp, your PH16 is doing all the gain and impedance matching you need.
    You could add a small passive box with a switch, but I'm sure you're smart enough to turn off your amp when switching sources anyway.
    In 99.4% of cases, I agree with PeterW on active preamps (I am unashamedly in favor of active pre-amps).

    Thanks Roy,

    I hope "retiring to Las Vegas" doesn't meant we won't be able to buy your kits anymore!!!!

    dave
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    tubes4hifi
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    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

    Post by tubes4hifi on Wed Jul 25, 2018 1:40 pm

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    Re: Running a PH-16 into an ST-120 with the 21 step attenuator in phono only system. Any benefit to a preamp?

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