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hot tubes
Silver Member
Canada
162 Posts |
 Posted - 03/15/2009 : 22:50:38
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after some basic mods it was sounding great , then i changed out
R50 to 100 ohms and then R36 to 47 k , this is when the sound
stopped working , do the resistor values seem right ? it will
pass audio with the effect off , but no sounds at all in the
on position .
any help would be great ......thanks ! |
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cctsim
Silver Member
United Kingdom
418 Posts |
Posted - 03/15/2009 : 23:11:04
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Hi hot tubes,
R50 to 100 Ohm is quite a drastic change. The original value is 1 Mega Ohm, which is 10000 times larger.
Does the pedal work if you put back the original values ?
R50 and R36 are part of the pre-clipping filter. What kind of sound/improvement have you been trying to achieve with these changes ?
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 03/16/2009 : 00:12:42
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I'm looking at the schematic and I can't see that these resistor values would inherently kill the sound completely (as for the potential change in tone... well, you'd have to listen and make up your own mind  )
Could there possibly be a solder "dag" left from the mod shorting something out? Could you provide pics of the area?
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cctsim
Silver Member
United Kingdom
418 Posts |
Posted - 03/16/2009 : 00:51:01
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I've just did a small simulation and the changes should give a flat frequency response. The output should actually louder with these changes.
Look also for a potentially broken wire.
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cctsim
Silver Member
United Kingdom
418 Posts |
Posted - 03/16/2009 : 00:56:00
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Original frequency response:
Modified frequency response:
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zerksies
Double Platinum Member
USA
3406 Posts |
Posted - 03/16/2009 : 02:03:55
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| i would say cold solder joint |
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hot tubes
Silver Member
Canada
162 Posts |
Posted - 03/16/2009 : 05:21:06
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the mod in question says that by changing these 2 resistors it will
help keep the tone clean when the gain nob is cranked , i would have
to agree that there is some room for improvement , it gets real
fuzzy / muddy when the gain is cranked. i have gone over my solders
several times , even checked my components ie. diodes , caps , and
resistors , they all check out good , like i said before the mod
was sounding great , but now .....no sound..!
i think i will try the factory resistors ! |
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hot tubes
Silver Member
Canada
162 Posts |
Posted - 03/16/2009 : 05:23:59
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OOPS !!!
THANKS FOR YOUR HELP SO FAR !!! |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 03/16/2009 : 07:55:19
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quote:
Originally posted by hot tubes
OOPS !!!
THANKS FOR YOUR HELP SO FAR !!!
Hi hot tubes
Does that mean you have fixed or located the problem?
Regards Dr. Bob |
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hot tubes
Silver Member
Canada
162 Posts |
Posted - 03/17/2009 : 01:50:54
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sorry for the confusion , i was just saying thanks for everyones
help so far , but the problem still exists .i 'm going to keep
digging away at it . |
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hot tubes
Silver Member
Canada
162 Posts |
Posted - 04/07/2009 : 20:53:25
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GOOD NEWS !!!
PROBLEM FOUND.
bad resistor , no continuity
replaced it with new one , great mod for the blues driver !
you can crank the gain and it stays clean & tight !! |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 04/08/2009 : 12:59:59
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quote:
Originally posted by hot tubes
GOOD NEWS !!!
PROBLEM FOUND.
bad resistor , no continuity
replaced it with new one , great mod for the blues driver !
you can crank the gain and it stays clean & tight !!
Hi tubes
That's good news.
Please post some pics of your work.
BTW, which resistor was it?
Did it get mechanically stress damaged when you were working on the pedal,
or perhaps it became overheated, when soldering?
Or was it faulty from new, when you bought the mod parts?
Regards Dr. Bob
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hot tubes
Silver Member
Canada
162 Posts |
Posted - 04/08/2009 : 15:17:05
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hello DR.BOB !
the resistor in question is R36 in the blues driver , i was using
a 1/4 watt resistor and it may have been damaged from too much
heat , i metered several more from that roll and all check out
o.k!
at the moment my digital camera is not working , i want to get
a new one anyway , sorry no pics at this time .
thanks for your help.
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Topic |
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BD 2 no sounds !! help !
