Nattawut Uamkruea, blogger and audio gear maker who passionate in vacuum tube, audio & music.
Producing electronics projects since high school. Seriously upgrade and modify vintage audio equipment for “Real Sound” concept.
He is a co-founder of Soundaries and Sentimental Studio, all audio solution provider.
Experienced and lively explore the listening rooms & audio shops in Japan as his most favorite to do.

Monday, July 27, 2015

Monday Modify : End of Life Phonostage modified

After finishing "End of Life" Phonostage for test.

Sound really good with macro and micro detail, speed so accurate.

But a bit bright and lack of deep bass present to the system.

So I think to replace almost PRP metal film resistors with other types

like tantalum, carbon composite and thick film resistors.

Also replace Black Beauty with West-Cap CPV09 for coupling capacitor.

Before ...

After ...

Burn-in for a while and found more bass and thicker sound.

But detail and dynamic still exist.

Might be continue burn-in and monitor again.

Next station, will test & taste LCR phonostage.


  1. That's very cool!
    I am interested in your LCR EQ experiments - I am on that path too....
    Many Thanks - Owen

    1. Thanks for your interest.

      Will update frequently and pleasure if you sharing yours with me.

      Still need suggestion about driving method.

      Best regards,

  2. Hi again Nattawoot- I have not built LCR EQ yet. Right now I am trialling a Lounge Audio LCR phono stage & I like what I hear - low impedance inductors allow the music to "breathe' better, I believe. (Similar to TVC attenuator characteristics.)

    I would like to include LCR EQ into my Phi-42 tube phono stage.
    But yes, which drive cct choice? - I am thinking maybe (i) low impedance mu-stage, or (ii) Interstage TX?

    I see that you will use the Sowter LCR inductor set?
    Cheers, Owen

  3. Hi Owen,

    Yes, I plan to use coils module from Sowter for first version.

    I will select drive solution with interstage before and after LCR EQ.

    After build and test, I will share you a circuit and result.

    Cheers from Thailand, Nattawoot

  4. Great - do you think interstage is necessary on the LCR output?

    I have some Tango NP-126 ITs.
    Cheers, Owen

  5. Hi Nattawoot - I don't see the RIAA LCR units on Sowter's website.
    What is the approx. cost for a pr?
    Cheers, Owen

  6. Sorry....I found it!
    Cheers, Owen

  7. Hi Owen,

    I think interstage necessary for LCR input, great result but more expensive.

    Nice that you found it.

    Lundahl also make the EQ coils too but 2 coils are separate.

    Cheers, Nattawoot