27% off for Fosi Audio T20X Bluetooth 5.0 Tube Amplifier Headphone Amp Stereo US$72.99 (~A$109.30) Delivered @Fosi Audio

Related Stores

Fosi Audio

• 

  Manny Calavera on 19/09/2022 - 21:02

  +2

  'Warm' sound from the compressed, digital waveform.

  Am I wrong in thinking that this is a nonsense?

  • 

    tonyjzx on 19/09/2022 - 21:09

    +1

    it is arguably nonsense

    the tube output stage should add that 'warm' sound on whatever leaves via the speaker or headphone outputs whether its bluetooth or analog in

  • 

    axlfan on 19/09/2022 - 21:33

    It has RCA input too so perhaps the "Warm" makes sense with the anolog inout.

  • 

    weewooo on 20/09/2022 - 15:50

    Maybe it looks nice, especially if the tubes glow in the dark.
    But I guess it could not be distinguished from a decent semiconductor-only amp.

• 

  PandaInPants on 19/09/2022 - 21:34

  +2

  You need to add GST to final price

  • 

    MarketingFosi Audio @ Fosi Audio on 21/09/2022 - 19:57

    We don't have a GST for these products.

• 

  Russ on 19/09/2022 - 22:22

  +4

  This isn't a "tube amplifier" in the conventional sense, it's a class-D semiconductor amplifier. Perhaps the tubes function as a preamp, to add that "warm" distortion?

  They even tell you, vaguely, in the description: "Amplifier Chip: TPA3221".

  The TPA3221 is a 200W-rated class-D semiconductor amplifier, manufacturer data here:
  https://www.ti.com/product/TPA3221/part-details/TPA3221DDVR

  Valve amplifiers, like the famous Fender guitar amps, have output transformers, because valves supply high voltage at low current. Speakers need moderate voltage at high current, hence the transformer. This device isn't big enough to contain two 100W-rated transformers.

  • 

    Astronaut Joe on 20/09/2022 - 09:39

    +1

    I suspect it's main function is to be a "tube" amp on your work desk.

• 

  bazingaa on 20/09/2022 - 17:16

  Amplifier Chip: TPA3221,

  Applicable vacuum tubes model: 6K4/6J1/6A2/6J4/GE5654/6AK5/66*I

  so more like a tube preamp ?

  is there any tube only amps with less wattage ? back then I was planning building one based on 12AU7 (low voltage) but never implemented

  edit: found this, any deals ?
  https://fosiaudioshop.com/products/fosi-audio-phono-preamp-f…

  • 

    Russ on 20/09/2022 - 18:04

    +1

    Why on earth do you want a tube amp? Nostalgia? Steampunk appeal?

    Tube amps have horrible distortion, which was perhaps useful for an electric guitar, but not for anything else. As soon as semiconductor amplifiers became cheap enough, in the late 60's/early 70's, tube amps were relegated to the trash heap.

    Anyone who tells you a tube amp is better for listening to audio, is either misinformed, or is trying to sell one to you and hoping you don't know the facts.

    • 

      bazingaa on 20/09/2022 - 18:25

      I was trying to design one for fun, to get that distortion mainly but I couldn't afford it. I was looking for 12AX7 equivalent 6N2P for cheaper price and use low voltage design (something like this https://www.youtube.com/watch?v=BTrUJC_vpyc). But never went through with the implementation.
      Vacuum tubes are still used in some applications though, where you can't generate high power at high frequency with semiconductors, like in satellite transponders etc

      • 

        Russ on 20/09/2022 - 19:21

        to get that distortion mainly but I couldn't afford it.

        There are other ways to achieve the "soft clipping" effect of valves, much more cheaply, like https://sound-au.com/articles/soft-clip.htm
        And http://www.muzique.com/lab/zenmos.htm

        Vacuum tubes are still used in some applications … like in satellite transponders etc

        Well, a Traveling-Wave Tube amplifier is not the same thing as a triode or pentode. If it was, then the klystron in my microwave oven is a "tube".

        The only place where I have worked with tubes is in high-power HF radio transmitters, where they do indeed have an edge, due to their high-voltage capabilities. And they're a bit more resistant to lightning strikes than semiconductors are, when appropriate defensive measures are taken.

        Note that HF radio transmitters are class-C amplifiers, they're not even close to linear.

      • 

        MarketingFosi Audio @ Fosi Audio on 21/09/2022 - 20:05

        How about this one Fosi Audio P1 https://fosiaudioshop.com/products/vacuum-tube-pre-amplifier…

    • 

      illogicalerror on 21/09/2022 - 11:35

      +1

      They're also really good for particular types of compression, if you are a producing sound engineer.

      But you wouldn't run your main channel through it.

      • 

        Russ on 21/09/2022 - 12:05

        Don't DSP effects units produce equivalent results, at a lower price, and with more versatility?

        Or are there still artists who insist on analog equipment only?

        • 

          illogicalerror on 21/09/2022 - 12:51

          +1

          @Russ: Yeah, maybe. I sold off a lot of my old analogue stuff because new digital stuff is just as good or better. Some of my analogue stuff just can't be reproduced digitally, to my ears. It's all digital recording these days though. DAT and reel to reel is dead.

          And knobs, knobs are so much easier to get "just right" than GUI sliders or MIDI interface controls. You can make machines do things by tweaking knobs just so, where computer programs don't know about these quirks of frequency and electricity. But computers have easy presets. So win, lose, win, lose…

          I think most modern producers have a mixture of digital and analogue stuff these days.

  • 

    Russ on 20/09/2022 - 18:12

    +1

    edit: found this, any deals ?

    That's not a tube amp either, emphasis added:

    Tube Phono Preamplifier: converts phono signals to Line Level Signals with Low-noise integrated circuits and …

    • 

      bazingaa on 20/09/2022 - 18:17

      goot catch, I missed it, the description was so confusing and looked like a tube preamp :D

      Matched Tubes: Tubes can be replaced by 6K4/6J1/6J4/GE5654/6AK5/66*In tubes etc, Different tubes with different sounds.

      Output Voltage Level: 600 Mv @3mV 1kHz

  • 

    MarketingFosi Audio @ Fosi Audio on 21/09/2022 - 20:03

    This is a phono preamp which is used for turntables, what do you do with the tube preamp?

• 

  toecutter69 on 27/09/2022 - 21:03

  How does this compare to the popular aiyima t9 that getting a lot of good reviews?