Switchable Hi-Z input impedance, how ?

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hey, I have played a bit with some black paint
'rubbing' the alu with black paint takes away the 'shine'
giving that overall more greyish titanium look
might be of interest to others
but remember, it only works on sanded finish

btw, it also matches 'glass blasted' stainless
which the handles on front just happens to be

and I also took a shot with no flash on
which I find especially interesting
because it gives a 'picture' of how it will look with them tubes glowing inside :D
 

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front mounted, done, finished, finally
and revised thoughts about control knobs, functions, etc etc :h_ache:
cant wait to get them knobs :D but money meter is a bit low now :(
 

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The cabinet is looking good. Plenty of room for wiring, board etc.
I suggest that you could put volume control after tone circuit bypass, and master volume after your 6n6P. Depends on how you like to control the different stages.
When switching in/out of the tone circuit or the differnt channels you may want to have levels all be about same.
 
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I suggest that you could put volume control after tone circuit bypass, and master volume after your 6n6P.

:scratch2:

btw, I plan use both channels at the same time, driving two power channels, and two speakers

thats why I need seperate channel controls, as well as a common master control
but Im also considering a channel balance control instead
Im interested in anything that works fast and easy ;)

regarding tone controls, 300-600hz seems to be the most important to control
or put differently, its where the center frequencies should be, to attenuate below and above
or at least it seems to be that way with my speaker system
 
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:scratch2:

btw, I plan use both channels at the same time, driving two power channels, and two speakers

and btw, low/mid tone control is for one channel, and mid/high tone control is for the other channel

I suppose some kind of clever switch 'arrangement' would make it possible to have both low/mid and mid/high for both channels

hmm, might be easier or better to have a switch to choose beteen different center frequencies :scratch2: but one of those things that might never be used once you have found the best one :crazy: but who knows, could be very practical and nice option
need to look at tone curcuit
probably too much complications
but on the other hand, those components are really small, so...
 

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man, I forgot it would need two controls per tone control curcuit

its beginning to look a bit tight
and forgot I also need a mute switch
if bypass switch has 3 positions, mute could be in the middle
but a toggle switch might be easier and faster to use
opinions ?
 

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bypass switch
I think it will take the signal directly to the solid state output, through a hi-z input jfet buffer

this way it will also be functional without tubes

and I will need a way to bypass any effect devices connected to input side

man, I hate it, but might have to put the power switch on the backplate, to get more room on the front
 
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ahh, regarding switches and bypass functions, there seems to be a few basic terms one needs know

single pole single throw = SPST
single pole double throw = SPDT
and so on
or if much more variations, there could be numbers instead
might be handy when looking at switches specsheets
and to know exactly which model to buy/order

for the bypass function we may need look only at SPDT, DPDT, 3PDT
 
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.... selector switch would seem to be the proper place for it

most likely, yes

Im working on it
with regards to attenuation pots, the tone controls seem to be a bit of a problem
but I could ofcourse just fill it up with buffers :eek::D

thinking about using only one tube instead of two
but easy to change
 

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Hi Tinitus,
If you are having problems with tone stack, maybe you should download Tonestack Calculator from Duncan Amps. It is free and very useful for setting up different resistance and capacitance. There are a lot of styles too, fender type vox, marshall. You could ''tune'' the response curves for bass. Are you getting too much signal attenuation on your tone controls?
 
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Are you getting too much signal attenuation on your tone controls?

looks like I mostly need cut/attenuation

but might be too early to say yet
having seperat biamped midrange and bass channel may change things
should give me more control
at least that was one reason of doing it
if Im very lucky I wont need anything else :drink:;)
 

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while waiting for power supply parts, hunting 6n1p curcuits

but why are there not two curcuits using same resistor values, or at least just the same anode voltage
but no, all different

could it come from 'adoption' of ecc88/6DJ8 curcuits
but 6n1p is not exactly the same
and 'ev' types maybe even more different
 
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