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DIY TDA1541A PCB "D3"

Would you like a through hole version of the D3?

  • Yes

    Votes: 12 52.2%
  • Maybe, depends on the performance

    Votes: 11 47.8%

  • Total voters
    23
  • Poll closed .
This tube output stage is sounding quite good, so I thought Id share it.
The cascaded DN2540 have stellar performance. Impedance in the gigohms.(attached)
Having the two stages DC coupled really helped preserve purity.
Other than the 13RIV im also using a NOS boost filter from a circuit attached only difference are my RIV is 13R and the other is 6R5.
Ill measure the THD soon, so I can post if anyone is interested.
 

Attachments

  • 6n23p tube stage cathode follower dc coupled ccs in anode and cathode 10k.png
    6n23p tube stage cathode follower dc coupled ccs in anode and cathode 10k.png
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  • ccs_performance_other.jpeg
    ccs_performance_other.jpeg
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  • thorsten last rlc+c risposta 47small (1).jpg
    thorsten last rlc+c risposta 47small (1).jpg
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  • dacout6im (1).gif
    dacout6im (1).gif
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I do remember when he soldered the 14 decoupling caps directly underneath the chip and soldered directly to the legs (I never tried this), but this was when he was still running the DEM at much higher frequencies. Now with the DEM running at 50Hz - much more capacitance is needed to filter out the 50Hz ripple, The D3 design was made because the D2 couldn't accommodate the 100u caps to allow a 50Hz DEM. To me the benefit of running a 50Hz DEM outweighed keeping the current loops tight like in the D2.
 
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Hi guys,
I'm really liking this tube stage, so clean with great control in the bass.
I attached the THD results of the 6n23p circuit in post #1301 driving a 100k load.
The 8k harmonic is a problem with my test setup as it is there all the time, so it can be disregarded.
The rising response and peaks at 16k onward are reduced when driving a 10k load and the harmonics increase by a few dB.
Overall im quite pleased that H3 is below -100dBc. I'll try and have a play around to reduce H2, but I think it sounds just great the way it is.
The power supply still needs some work to reduce noise but even with my 95dB/W speakers I dont notice much of an issue once the solar inverters quiet down after dark.
Ok, im going to reconnect my F5 and enjoy the music!
Peace everyone!
:) (y)
 

Attachments

  • tube stage THD.JPG
    tube stage THD.JPG
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Last edited:
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