Switchable Hi-Z input impedance, how ? - Page 14 - diyAudio
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Old 28th May 2012, 11:52 PM   #131
tinitus is offline tinitus  Europe
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man, why do I buy all this stuff
but now that I have a couple of these LDR att boards, and some matched LDR as well, why not try and put it in there

well, all effects have their own attenuator, so it I guess it will have its natural place at tube pre out
and this way be able to control both channels of my stereo power amp
now is that not clever or what
you are invited to argue on that

btw
I just managed to construct a backplate from my leftover (s)crap profiles
oh, and them nice mounting screw are from a scrapped PC
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Old 29th May 2012, 02:30 PM   #132
tinitus is offline tinitus  Europe
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time to get on with it

hmm, 90mm clearence should just about do it for the bigger 6n6p

man, I still havent got around to the lacquer
front need to be assembled for that
sets me back some
its definately next on the list
and ordering hardware bits and pieces
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Old 29th May 2012, 08:49 PM   #133
tinitus is offline tinitus  Europe
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seems like I have to make a few small changes to the chassis, and rearrange a bit, not to waste too much space

but man, Broskie's boards are just so bloody big
not to be hard on him, but only shows how high the level is here, among our own members

green one is a regulated supply from Broskie
just plain basic design, and still so fu... big
would never have bought it, had I known this

and the neat black one is 'our own' Hynotize symmetric B1 jfet buffer with shunt regulation, twice as much, and less than half size
well, admittedly, even the pros might find it hard to compete with this
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Old 29th May 2012, 10:26 PM   #134
tinitus is offline tinitus  Europe
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call me nuts
but now seriously thinking about cutting the copper traces to the tube sockets, and hardwire the 6n1p and 6n6p for a double mu stage follower

I think it should work ok with half 6n6p for top triode, and half 6n1p for bottom triode
that would give two channels, or stereo out, if you like
might be more convenient to have a stereo preamp, later on
funny that there is actually a 2-channel out, with plenty of space for two big output caps, on this mono board
maybe I will cut it away, maybe I wont, dont know yet
but the space is actually one third of the board
but if I it cut away, it may still be of use to hold the caps, and placed somewhere else more convenient

maybe I will be able to use some of the copper traces


man it pains, but might have to be
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Old 30th May 2012, 07:01 AM   #135
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by tinitus View Post
...... 6n1p and 6n6p for a double mu stage follower
but a simple gain stage with cathode follower might make more sense
a possible attenuator pot would then be buffered
and the preamp would work work 'as is'
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Old 30th May 2012, 10:39 AM   #136
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by tinitus View Post
call me nuts
but now seriously thinking about cutting the copper traces ...
maybe I will cut it away....
man it pains, but might have to be
no, I could not do it
sure hope I'm still in the clear with the Aikido guys

but I can use the parts, and not loosing any sleep

so I'm doing this instead
well, the copper print will be underneath the brown plate
just need a couple of big holes for the sockets
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Old 30th May 2012, 04:25 PM   #137
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by tinitus View Post
well, the copper print will be underneath the brown plate
just need a couple of big holes for the sockets
like this
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Old 1st June 2012, 12:58 PM   #138
tinitus is offline tinitus  Europe
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hey, got the idea; why not place a couple more prints, and prepare for the optional solid state output, or whatever

and got the copper side tinned

and another brown plate to hold the various power supply curcuits needed
might look neat with some axial supply caps
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Old 1st June 2012, 02:20 PM   #139
shanx is offline shanx  Canada
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Hi Tinitus,
The build is looking really nice, and yes that middle board is begging for some axial caps (turret mounted would be, oh so sweet)
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Old 1st June 2012, 02:33 PM   #140
tinitus is offline tinitus  Europe
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thanks

now that it have become more 'old style' tube design, Im also thinking about some passive tone controls, adjusted for bass guitar
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