Issues/Queries after S.E.X Build

[gabu840]

Hi All,

This has been my first build , yes the soldering skills aren't great and the work is not clean . My questions n queries :

1) Mine a 240v amp , would require your suggestion to buy a power cord of good quality for it as the one Bottlehead has in its store is for 120v only.

2) There is interference basically noise , with Beyer T1 I can clearly hear this noise/interference starting from 1o clock position of Potentiometer & with Audio Technica AD700 its clearly audible since 10'0 clock position . How can it be removed.

3) Many a times Hiss/crackling sound comes in b/w randomly from left/right channel sometimes when Amp is touched & sometimes randomly which is very  very piercing to ears .

4) HUm sound is present , sometimes just by touching tubes , it is removed but then comes again.

5)While putting Left & Right channel Aux cables too much interfernce comes , can it be removed?.


Awaiting for your answers so that I can remove these problems & get a clean sound.If needed I can put up pictures of built.

Also Extra question : When First time kit was made on there were sparks from one of the Blue capacitors as there were spots made by soldering iron on it while soldering . After that it was normal . Does the capacitor needed to be changed or its fine?

FYI..C4S upgrade is not being put-up yet, wanted to clear these issues first.


Thank You.
Ojasvi

 

[gabu840]

And all resistor & voltage readings were correct.

 

[Doc B]

You need to go back and make sure all of your solder joints are properly done. The best thing to do is reheat each one until you see it flow into the connection smoothly. If you find any that seem not to have enough solder add just a little as you reheat the joint.

 

[gabu840]

That means its just the connections are bit loose, need to tighten them up ,Okie lemme get it done& revert with the status

Also Doc, any suggestions for the power cable?

 

[gabu840]

Well Guys/Doc everything was running fine until I thought to melt and heat the dry solders onto sex amp.

After then the issues started , first tube didnt glow, melted & tightened many soldering esp. diode rectifier areas.
Then tubes start glowing but no sound. Check the res/vol reading . Res. readings were correct everywhere but voltage ones were all wrongs except at A6/A5, B5/B6 terminals .
Checked all wirings and reheated some terminals removing some which looked like solder blobs. All resistance reading are again correct , bit on powering on, siren kind of or say steam kind of sound is coming from both tubes .Bcs of it I put off the system & didnt took the voltage readings this time.

Whats the possible next step. Is it that some capacitior/rectifier/diode has blown off. In that case how to check all components themselves are working fine or not?

 

[gabu840]

Suggestions People!!!

 

[johnsonad]

Your additude isn't going to draw a lot of help. You may want to look at the technical pages and review the videos on proper soldering techique. There is a good chance your problems start there. Without any photos though it's hard to tell. Good luck.

 

[gabu840]

Well john nothing offensive bro , but where does attitude now comes here in question..There are many newbie's or say first time diy builders so it take time for them ,people learn via experience only, me being one amateur in this .
Also Doc told some story in some forum where some people laughed at  stuff saying how can one not to know proper solder , upon which Doc calmly supported all the new diyer's that all start with scratch until they become really good ones a day.

I will try to more simplify my question (may be it look like a noob's question but thats what am stuck at) :

At current condition when powering on is creation siren kind sound from tubes shall I go ahead checking voltage readings or it could be some dangerous or could short any equipment .Will post pics asap for further help.

 

[Doc B]

It sounds like your amp is squealing - which is oscillation. That is most likely due to a bad solder joint or oxidized tube pins. I would suggest turning on the amp and doing all of the voltage measurements again, and posting the values of terminals that are not within the specification in the manual. From there we can try to narrow down where the problem might be.

I think Aaron's response was not to your asking a perfectly good question, but rather in response to then demanding suggestions when it wasn't answered. It does appear as showing some level of impatience with the participants here, whether intentional or not. To some extent the tone of an inquiry will determine the quantity and quality of the assistance given in response.

 

[gabu840]

Ok , lemme check with it & come back.
Also agree on the second point .

 

[Paul Birkeland]

Pull the tubes out, then check your voltages, specifically what you see at terminal 4.

-PB

 

[gab840]

Sorry  from my side for delayed reply :

The voltage reading are as  :                                     
Terminal:ReadingTaken       Values Actually mentioned in Document     
1: 245                                    210                     
2: 0                                        0                       
3: 0                                        0                       
4: 490                                    420                     
5: 260                                    210                     
6,16: 490 ,490                      400                     
7,17: 0,0                                0                       
8,18: 0,0                                0                       
9,19: 0,0                                close to 0               
10,20: 490,490                      420                     
11,21: 490,490                      380                     
12,22: ~0 ,~0                        0                       
13,23: 0,0                              0                       
14,24: 0,0                              0                       
15,25: 0,0                              19                       
A1,B1: ~0, ~0                      close to 0               
A2,B2: 490,490                    375                     
A3,B3: 0,0                            19                       
A4,B4: 0,0                            0                       
A5,B5: 0,0                            75                       
A6,B6: 0,0                            2.5                     
A7,B7: 3.08,-3.18                -3.15                   
A8,B8: 3.73.3.65                  3.15                     
C1: -3.4                                -3.15                   
C2: 3.9                                  3.15                     
C3: 0                                      0                       
C4: 3.32                                -3.15                   
C5: 3.85                                  3.15                     
                                                                   

 

[Paul Birkeland]

Yeah, I agree, if you're touching the amp and it produces noise through the headphones, this is nearly always a flaky solder joint that you are disturbing, which needs to be reheated.  Occasionally it can just be loose hardware as well, so try tightening down all the screws.

Also, is your power outlet grounded?  Did you happen to paint the bottom side of the chassis plate?

 

[gabu840]

No internal of the chasis isn't painted,  & power outlet grounded : yes as per the documentation.
Haven't been here for some time , reason being am out of station due to office project or quite some time, shall be returning at the end of this month, then will continue troubleshooting & will post pics.
Thanks!!