blackmoon: my commercial grade cherry keyboard was like that
the stiff most untactile keyboard ever
built on a thick ass piece of steel
bongwater killed it
Posted by renesis at 20:07 | permalink | 0 comments
lordpil's blog
hahaha holy fuck theyre $17!
haha i want 4 and price break is at 5 =\
Posted by renesis at 13:12 | permalink | 0 comments
synth: i was never too interested in ancient guitar electronics (except muff pi and rat circuits), but my face was rubbed into it at work
http://www.bourns.com/data/global/pdfs/95.pdf
for example 5 years ago i never would have thought id be buying these...
Posted by renesis at 13:04 | permalink | 0 comments
but shit from fender and marshall will often have old tone circuits that just look like a huge random cludge of caps and resistors
and smaller companies, especially boutique shit, could be anything
k night
np!
Posted by renesis at 12:45 | permalink | 0 comments
lots of guitar amp and effects circuits from the volve era are known to be a bit strange, sometimes silly
*valve
like, opamps kinda of make a ton of things super easy, they had to accomplish less ideal things with a handfull of caps and resistors
doesnt matter =)
new stuff is often just a compilation of older circuit parts
because it has a 'sound' and a 'feel'
yeah lots of amps have DSP front ends, but theyll feed old tube output sections
but yeah guitarists kinda get a tactile sense for the overdriven amp response
like, basically how it starts breaking up
shit like that is hard to model with solid state or DSP
vortran: right exactly
you could make a better amp, in terms of specification, but they would be pissed
so most valve amps are very old circuits
alot of the tone circuits too
moderns heads will use pretty typical active EQ circuits
Posted by renesis at 12:40 | permalink | 0 comments
the EMI would generate voltage across the resistors, and then ride an AC wave, which should help it couple into the tube screen/plate/grid/whatever
but discrete layouts are all diff
very high voltages, very big conductive surfaces, lots of capacitance, so noise, hum, it gets around easier
so this may have been some fix for some random grounding issue
all this interference is getting in on the heaters and fucking up system grounds, so lets try damping it with these resistors
yeah its ungrounding them
like, floating them but not completely
its quite possible though that the transformer winding was too hot, like it was made for more tubes, who knows
so the resistance is just to get the voltage down
well its a guitar amp
Posted by renesis at 12:35 | permalink | 0 comments
like, one side would swing 3V the other side 6V
vortran: it might be a way to isolate the ground
if you had one side directly to ground, its possible that EMI could get caught in the coil and dump out into ground
well its not really floating
so you dont want the coil grounded right
so first instinct, just unground it, but itll blow up those caps, sometimes for no reason
the 200pF or whatever value caps from the coil to ground
but if you put resistors there, you still have a higher impedance path to ground
so you wont float, you wont dump so much crap into the ground
i mean, the other side of that is that it would prob make the heaters noisier
Posted by renesis at 12:30 | permalink | 0 comments
is it drawn right or are the other sides of those parts supports to be grounded or something?
weird
anyway, as for the heaters, it keeps both sides of the heater at AC
assymetrically
same for the transformer coil (as its in parallel)
yeah thats what im talking about
its not really a divider
theyre just loads to system ground
oh, because theyre very low voltage
6.3V or 12.6V
theyre almost always on their own transformer coil
well it might be for the transformer coil
load it up to get the correct voltage
its assymetrical tho
Posted by renesis at 12:25 | permalink | 0 comments
what are C47, C46, and and P1 about
ooooh, k found it
Posted by renesis at 12:20 | permalink | 0 comments
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