Bottlehead Forum

Bottlehead Kits => S.E.X. Kit => Topic started by: Todd R on December 29, 2012, 06:09:54 AM

Title: C4S Board for SEX 2.1 manual correction and suggestions
Post by: Todd R on December 29, 2012, 06:09:54 AM
Hi Doc,
Got the C4S board installed today, listening to it right now.
Slightly quieter with my very sensitive JH Audio 13's. Bass is tighter & punchier with all headphones.

Page 11 of the manual:
Cut an 8
Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: fullheadofnothing on December 31, 2012, 08:47:12 PM
Todd, you're right about that second typo. As for the 8.5", did you route that wire as shown? The idea here is to keep the wire away from the high voltage wire that connects the power switch to the inlet to minimize noise.

Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: Todd R on January 01, 2013, 01:47:01 AM
Todd, you're right about that second typo. As for the 8.5", did you route that wire as shown? The idea here is to keep the wire away from the high voltage wire that connects the power switch to the inlet to minimize noise.

Not exactly. I kept the wire away from the power wire but instead of looping it around like the manual shows I spaced it vertically away from the chassis plate and came down to connect to the tube socket. Seemed easier.
Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: ditdah on January 18, 2013, 06:57:03 PM
Todd,
Thanks for the corrections and note on the wiring.  I just put my C4S together today and installed it.  I ran into some install space issues and took a "vertical" approach to the wire routing as I found it just too crowded closer to the plate.  I have the impedance match kit in there too...so, lots of wiring is stuffed in that area.  I also had to mount the board through the hole closest to the tubes (thankfully there are 2 holes in that board), which put it more in between the 2 transformers.  I have all those caps in that vicinity mounted at about 45deg...to help allow for cable routing and avoid contact with the adjacent terminal board.  The C4S board wouldn't fit over them.  I also did not take off the nut from the terminal board mounting area.  There was enough thread protruding past the nut to just thread on the stand off as it was...and it gave it a little more height that I felt it needed to clear everything.

Only odd thing I saw during voltage checks was that on OA/OB...I was expecting 75VDC...but one channel gave me just about 10% lower, while the other channel gave me 10% higher.  I'm wondering why the mismatch.  I would have thought both would have been lower or higher symmetrically.  Anyway...I considered (hoped) it good to go and plugged it all in and gave it a listen...still listening now ;)  I don't perceive any issues in sound volume per channel or any other issue.  She's dead quiet and sounds phenomenal through my LCD3's and my Orcas :D
Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: Paul Joppa on January 20, 2013, 02:10:57 PM
That voltage (OA/OB) is subject to especially large variation due to small differences between tubes. It is inconsequential.
Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: ditdah on January 20, 2013, 03:03:52 PM
Paul,
Thanks for that reassurance.   ;)
Title: Re: C4S Board for SEX 2.1 manual correction and suggestions
Post by: jimiclow on March 23, 2013, 06:10:54 PM
Hi Paul,
I just finished installing my C4S.
Just like Ditdah, readings on OA/OB were 65/95. I hope these are okay. Music is playing on both channels.
Thanks.