Pre S.E.X. Order/Build Questions

RDF · 1048

0 Members and 1 Guest are viewing this topic.

Offline RDF

  • Newbie
  • *
    • Posts: 3
  • I come in peace...
on: March 07, 2023, 12:17:42 PM
Hello All  :)

I currently use HD600's and LCD-2C's with my Schiit Valhalla 2. I love the tube sound, but while still very appealing, the LCD-2C's (70 ohms, sensitivity 101db) lack a little something. My research indicates that the S.E.X. would be a good match for them. Is this correct?

Additionally, I would like to use it to drive speakers. How should the S.E.X. be wired, 4,8,16, or 32ohm? (The LCD-2C's still being the priority.)

What happens if a tube blows, do I need a matched pair?

What are the alternatives to the 6FJ7 tubes if they were to become unavailable?

Thanks to everyone in advance :)
Robert



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19316
Reply #1 on: March 07, 2023, 12:50:01 PM
Hello Robert,

I think the SEX would be a good match.  What kind of speakers do you intend to use with it?  Typically we suggest wiring for 4 ohm operation when headphones are a priority, as this trades away power that you don't really need for a lower noise floor. 

If a tube blows, you just need to snag a replacement.  The 6FJ7 has been a tube for decades in zero demands, so they are a bit tough to find but at the same time still somewhat common.  If you build your SEX amp, turn it on, then never turn it off, you can expect about five years of tube life.  If you run the amp 2-3 hours per day, tube life will be in the decades.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline RDF

  • Newbie
  • *
    • Posts: 3
  • I come in peace...
Reply #2 on: March 07, 2023, 02:05:30 PM
Paul, thanks for the reply. The speakers I have right now are some old Polk Monitor 60's (8 ohm 90dB). I wouldn't expect much out of them with the S.E.X.
However, the goal is to eventually run a pair of Zu Dirty Weekend (8 ohm 99dB) or a pair of Klipsch Heresy 4's (8 ohm 99dB) or Cornwall 4's (8 ohm 103dB).
But again, the LCD-2C's are the priority, at least for now.

Thanks, Robert



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19316
Reply #3 on: March 07, 2023, 02:07:49 PM
The Heresy and Cornwall speakers will prefer the 4 ohm configuration.  DW and Polks may work a bit better with the 8 ohm configuration.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 752
Reply #4 on: March 07, 2023, 02:50:14 PM
On my S3X I mounted a 4pdt switch by the inputs to select between 4 and 8 ohm transformer settings.

Lee R.


Offline RDF

  • Newbie
  • *
    • Posts: 3
  • I come in peace...
Reply #5 on: March 08, 2023, 11:41:54 AM
Thank you guys for the help! I'm ordering the S.E.X. this week or the next, but I can't find my Fluke meter, ugh.

Robert



Offline Karl5150

  • Sr. Member
  • ****
    • Posts: 618
Reply #6 on: March 09, 2023, 02:37:27 AM
Dig out that meter and warm up the iron - enjoy the build and the music it brings. Don't forget the pics.
(It just occurred to me that this is possibly the only site where wishing someone luck, asking for advice and posting pictures of their SEX doesn't get weird, or get you sent to HR)
Karl

Karl
Downstairs: Planar3>PH-16>Stereomour II>OB Betsy+
Upstairs: RP1>Eros/CD5004>Seductor (2x Monoblocks)>FH3
Office: Modi Uber 2/Sirius>SEX2.1.1>µFonken FF85WK + DC160 subs
BR: FiiO M6>SEX3.0.1>ScanSpeak 10F + TangBand W6 (Mono)/DT770Pro
Garage: X12 streamer>Quicksand>Minimus 77