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Laowei last won the day on April 3

Laowei had the most liked content!

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About Laowei

  • Rank
    Limited Edition Bronze Participant
  • Birthday 06/07/1957

Profile Information

  • Gender


  • Headphones
    Stax SR-009, SR-207, SR-003mk2
  • Headphone Amps
    KGHV-Grounded Grid
  • Sources
    Mac mini > Schiit Yggdrasil
  • Other Audio Gear
    DIY PP 6V6 amplifier. ALTEC 890C Bolero/Econowave modded speakers

Recent Profile Visitors

2,329 profile views
  1. Happy Birthday Pars!

    Happy Birthday!
  2. Happy Birthday MPI!

    Happy Birthday!
  3. Goodbye Tyll. Happy Travels

    You’ve left a big mark on the headphone industry and the enjoyment of many who followed you. Best wishes on your next adventure, Tyll!
  4. The Headcase Stax thread

    EL34, 6CA7 and KT77 all have the same functional pinout, so don’t know why adapters would be needed. EL34s and small bottle 6CA7s are pentodes with suppressor G3 brought out on pin 1. Big bottle 6CA7s and KT77s are beam power tubes. NOS and Russian reissue tubes are tetrodes and have the beam forming plates internally tied to the cathode. JJ 6CA7s and KT77s are beam power pentodes which the beam forming plates are brought out on pin 1 for external connection. Depending on the circuit these JJ tubes may cause problems if the beam forming plates are not connected to cathode potential. Justin at Headamp explicitly says NOT to use the KT77 in his BHSE amps. SO DON’T USE THEM IN HIS AMPS. I’m currently using a quad Gold Lion KT77s in my GG, and liking them a lot. The opto-servo in the GG might be the reason they work here (so far.....). Does not necessarily mean they will work as a EL34 replacement in all cases.
  5. The magnetic circuit on the AEON is singled ended, with magnets on only one side (ear side) of the diaphragm. Electrically, it can be driven by a balanced signal, so you should be good to go.
  6. Cobra Kai

    Cobra Kai, series 1st season just released on YouTube. First 2 episodes free, 8 remains episodes available on YouTube Red for a monthly fee. First month free, cancel anytime. The story is a continuation of the original Karate Kid movie, now 34 years later. Picks up where Daniel and Johnny (same actors) are in their respective lives, and where they and their families get tangled up again. Less emphasis on Japanese mysticism, more on kicking ass. Extremely well written, acting and production. Awesome plot and character twists, parallels and echos of the original. Best part is it’s non-PC humor and look at today’s culture with a 1980s perspective. Lots of music from that era too. The series is strong in all 10 episodes without a letdown. Started watching the first 2 freebies, and got so caught up ended up binge watching all 10 in one day.Season 2 has been given the go ahead. Recommended. Check it out.
  7. New cans for a very *bad* Head-Caser.

    Should call it “The Gimp”.
  8. The Headcase Stax thread

    A recent tour thru the STAX HQ posted on a Chinese website: https://mp.weixin.qq.com/s/L2VLqiNk-a_wE5eA5VbRhA The text is Chinese, not Japanese Kanji. You can translate by copying and pasting the URL at either Google or Bing websites: http://itools.com/tool/google-translate-web-page-translator https://www.bing.com/translator/
  9. grounded grid

    The zener provides over voltage protection for the 4N25 optocoupler when adjusting the offset. A 12V zener is used on the Carbon and works there OK. That value was carried over on the GG PCB, but was found close to being too low when setting the offset in that circuit. So Kevin advised using 18V as a replacement to give a little more headroom.
  10. grounded grid

    Agree if the offset is measuring positive voltage. Chinsettawong might consider engaging the opto-servo. If the offset is measuring negative (like my GG when running at +/-400 @ 15mA per tube), I went to a 200ohm tail resistor and was able to adjust to ~0V.
  11. grounded grid

  12. RIP some fuck or another

    RIP: Verne Troyer. “Mini Me” in the Austin Powers movies.
  13. The Headcase Stax thread

    Well, STAX is owned by Edifer now, so worldwide IP can be “borrowed” (at least for marketing).
  14. The Headcase Stax thread

    So, an improved SR-009 with SR-L300 LE derived MLER and Audeze Fazor tech?
  15. The Headcase Stax thread

    And removing solder flux from PCBs.