S.E.X. 2.1 Voltage Question

[mcandmar]

Not convinced that was the source of your issues so keep going and check everything out.

Are you in the US or UK?  I have those parts spare i can send you if your in the UK.

[Adrian]

I'm in the US.
Thanks for the support.

[Paul Birkeland]

Is that capacitor in correctly?  They usually bulge when they are in backwards, and they will bulge until they explode.

[Adrian]

Yes
I thoroughly checked every wire and component twice and re-flowed many connections after I discovered I had a problem with the left channel.
I really think I smoked it during the initial voltage checks and failed to stop and ask the critical question:  What's the worst that could have happened with this tiny puff of smoke?

[Adrian]

While I'm waiting for replacement grid stopper resistors (one cracked - overheated) and a cathode bias capacitor (swollen and suspect) I have very carefully checked every wire, component, and connection thoroughly. - TWICE.  This makes four complete times going over every installation step.  I swear I could wire this thing in my sleep.  I can find no evidence of shorting or bad connections and I have re-flowed or totally reconnected many joints 'just to be sure'.  So, I'm left with putting in the missing parts I'm waiting for, doing the resistance and voltage checks and going from there.
Because I was not getting any left channel through the HP jack I have carefully compared the right channel to the left channel and I have found only one variance.  This is how the 1.5 microF plate blocking capacitor is oriented - the left plate choke was running hot.  The two blocking capacitors are metalized polypropylene type and probably do not require any special orientation in the circuit but I have to ask:  Should I reorient it to match the right channel?  If so, I'll have to get another one because the leads are not the right length to turn it around (unless I solder an extention to one end).
Anyway, before the parts arrive I will get a jeweler's loop and visually check every sq cm of this sucker.

[mcandmar]

Direction of the film capacitors doesn't matter so nothing to worry about there.

[JamieMcC]

Its worth getting an illuminated magnifying glass or loupe, plenty to chose from for only a few $ on ebay

[Grainger49]

Adrian,

If you have gray hair like many of us here (PB not included) the illuminated magnifying glass is good to have.  You should be able to get one under $40 at MCM electronics. 

I've been using one since my late 30s.

http://www.mcmelectronics.com/product/21-10255

[Adrian]

Grainger49:  Yep, grey hair pushing 62.
I use a desk mounted, lighted magnifier but a handheld device would be more useful in some cases and places.

[2wo]

For a good lighted handheld, look at what the stamp and coin guys use...John

[Doc B.]

Also consider checking out the magnifier apps for the iPhone if you use one. Saved me more than once.

[Adrian]

Thank you - thank you everyone -- SUCCESS!  I replaced the suspect cathode bias cap and the 220R grid stopper and headphones and speakers work great, well sorta.  I still have the constant buzz in one channel with a much softer buzz in the other (both HP and speakers) that swaps channels when I swap the valves.  Because this moves from channel to channel with the valves I am going to assume for now that these valves need to be exercised.  I'll run this unit for about a weeks run time and watch for the valves to awaken from their long slumber on the shelf.  Here are a couple of pics - please excuse my out of date camera phone and generally poor photography skills.

As you can see I did the entire top in black-on-black and finished the base with an ebony stain.  I like the way it turned out but probably more important the WAF is also high.

[Doc B.]

The ebony finish looks very nice, very ebony-like.

[Adrian]

I'm continuing to run-in these valves hoping the bee-buzzing from primarily one channel (swaps channels with valves swap) subsides.  I wired the output trannys for 8 ohms to for use with speakers and lower impedance phones.  I have a pair of NAD VISO HP50s that sound great using my ZUNE player and want to also use these at home and not just commuting and at work.  But the buzzing is not right and must go away.
Will installing the C4S on the S.E.X. help quiet buzzing valves?

[Paul Joppa]

It is very unlikely that the C4S will affect the tube (valve) buzzing. The buzzing is probably heater to cathode coupling due to poor isolation between them. Often this will sort itself out with some running time. Give it 50-100 hours of operation - that's just a guess, there is no science to it, but it often works.