Seduction build query

[porcupunctis]

That could add a layer of complication that you really don't need.  What kind of treatment did you do to the chassis?  Would it be too hard to treat the correct side before you build? 

I've been reading through the instructions and plodding through the wardsweb build in anticipation of doing my own seduction.  Doing a "mirror" build would not be something I would want to take on without a really good reason.  The chances of getting it screwed up like Hogan's Goat increase exponentially.

[Laudanum]

And another query: I accidentally prepped the chassis plate so that the sides are reversed, i.e. when looking at the underside with the the sockets near you the power entry/fuse holder is to the right, not to the left. Will this be a problem for me later on?

Theres not all that much to it.  A few screws and the power entry.   I would just start over.  Unless of course you painted the plate ...

[denti alligator]

Yes, I painted it. I could simply paint the other side and start over. Would the painted underside be a problem? Or I could get me some paint thinner...

[Grainger49]

Sam,

Are you saying that the plate is upside down?  If so, it will be confusing throughout the build.  If it were me I would reassemble it.  That is, if I understood you.  You could just remove everything leaving all the wires on them, flip it and reinsert everything.  Any wires that need changing you change but it is a big step up.

[denti alligator]

Yup, upside down. I haven't wired anything yet, so it's no big deal. In fact, I just removed everything from the plate in less than 10 minutes.

The question is: will the painted plate be a problem for the underside? It's a pretty thick few layers of paint and gloss, and it's black, so that may make numbering difficult.

[mchurch]

As far as the painted plate is concerned just make sure you polish or grind off the paint where the parts attach to it particularly the grounds and terminal strip mounts as the centre terminals are grounded to the chassis. If you have something like a Dremel tool the cleaning of these points is easy with a grinder or wire brush attachment. If you are concerned about numbering you can get a white or silver coloured pencil from an art supply store or a fine tipped paint pencil from a hobby shop. They work fine. Also you can get white grease pencils and just sharpen the point a bit.


Cheers

[Grainger49]

Sam,

I just PMd you that I painted both sides of my Seduction plate.  I used a Dremel tool (good excuse to get one, every man should have one) with a wire brush to remove the paint around all the screw holes.  It works fine, no noise.

Grainger

[Grainger49]

Sam,  (Simultaneous post with mchurch)

I just PMd you that I painted both sides of my Seduction plate.  I used a Dremel tool (good excuse to get one, every man should have one) with a wire brush to remove the paint around all the screw holes.  It works fine, no noise.

Grainger

[denti alligator]

Flathead screwdriver and some steel wool did the trick. OK, back to stage 1. I'm painting the right side now....

Thanks everyone.

[denti alligator]

OK, I'm done with the build. Resistance readings all look good, except for A3/B3 which is 25.96M/21.10M (should be 1Meg+) and A8/B8 which is 23.26M/26.92M (should be 1Meg+).

Are these readings 20-MEG?, and is that OK?  Wiring seems to be fine, and sliver strip on LEDs in facing the right way.

[Paul Joppa]

"1meg+" means it's only a problem if it's less than 1meg.

Actually at those points you are measuring the resistance of the LED, using a voltage that (depending on your meter) is too low for it to conduct. Different meters will give different results; if you get a low value (a few K ohms) and the LED lights when you test it, you are probably still OK.  :^)

[denti alligator]

Thanks, everything else tested out great.

And it sounds great. Only thing is that I'm getting a strange pitter-pattering sound in the right channel only. It's barely audible at low volume, but when I crank it up (as I like to do), it's definitely audible, especially with cans on.

I don't recall hearing this sound with my other pre-amp, so I don't think it's the 'table. And it's definitely not my amp (the SEX). What could this be?

UPDATE: the interference is coming from the room somewhere. When I lift the Seduction up it goes away. It's something coming through the desk I have it on. Will have to experiment with placement, etc.

[Grainger49]

The pitter-patter sound might be an RF interference.  You have the tube shields in place, right?  Is there a phone or computer (today the same thing) close to the Seduction? 

Try jumpering in a pair of the 200V 0.1uF KK Teflons.  Just use RS cheap jumpers so they can be removed and inserted easily.  Just lift one lead on each cap.  Remember there are voltages there that can HURT you.  The insulator on the alligator clip will protect you if you don't touch the conductors.

[Laudanum]

Thanks, everything else tested out great.

And it sounds great. Only thing is that I'm getting a strange pitter-pattering sound in the right channel only. It's barely audible at low volume, but when I crank it up (as I like to do), it's definitely audible, especially with cans on.

I don't recall hearing this sound with my other pre-amp, so I don't think it's the 'table. And it's definitely not my amp (the SEX). What could this be?

UPDATE: the interference is coming from the room somewhere. When I lift the Seduction up it goes away. It's something coming through the desk I have it on. Will have to experiment with placement, etc.

Swap tubes, see if it moves with the tube.  I would think that outside interference into the amps ciruitry itself would show itself in both channels.  So make sure it isnt the tube itself.