DG300b Build Thread

Discussion in 'DIY' started by Jh4db536, Jan 3, 2017.

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  1. purr1n

    purr1n Desire for betterer is endless.

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    Looks like you are running those Mable Advanced 300B now? What OPT were you running before with the 5K primary (5k to 8-ohm I assume)?

    The DG300 runs the 300B's pretty hot no? LOL, you probably preferred a sound closer to what is typically the 300B sound.
     
  2. Jh4db536

    Jh4db536 Friend

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    The 5k:8 were electraprints that i started with, which were pretty nicely made. The DG300b runs toasty 400V@85mA. I'm running it only at 65mA right now

    i personally prefer the interstaged 2a3 or 45 sound. I might have to put a pair of elrog300b in order to get this to sound the way i want. There aren't that many levers to change the sound with this design. Tubes, Bias, coupler cap and transformers.

    yeah these are lopents that i finally got around to installing. I haven't really seen usage reports from anyone else. there were some trade offs going this direction, one of the biggest trade offs for engagement factor and timbre was the really nice attack the Amp had with the 5k electraprints. it's kinda too soft rn

    i have another pair to try later as well. Lots of diy lately, ill post more of my recent adventures soon.

    [​IMG]
     
    Last edited: May 31, 2021
  3. purr1n

    purr1n Desire for betterer is endless.

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    I meant hot in terms of pushing the 300B with respect to voltage and bias - hence the 5k load recommendation.

    The Lopents (of which I run a modified version of with a tertiary) do have a inherent mellowness which reminds me a bit of these amorphous core Tango OPTs I once heard, although the Tangos were even more mellow. It seems difficult to get the best of everything. Report back if those C-cores work out.
     
  4. Jh4db536

    Jh4db536 Friend

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    I definitely hear the mellowness with the lopents compare to EP. Maybe I need to increase the bias back to 75 - 85mA (currently running it 400@65). It is entirely possible that EP 3.5k might be the correct synergy for this amp

    Might also be the genalex 300b. I know the Phillips cc88 drivers that I'm using are capable. The coupler cap doesn't seem to be a sensitive part in this amp so I used the Jupiter's for another build.

    I completely agree with the difficulty on getting the best of everything. Likely changing to er300b which are really modified 845 is the only way to radically move the needle here
     
    Last edited: May 31, 2021
  5. Tommy

    Tommy Acquaintance

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    Oh, this thread is making me drool. Missed out on the last few sets of pcbs. One can only dream. :)

    FYI, I found the sound clip sounded better than the actual recording on YouTube. Great work!
     

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