make your own BOM, great for learning
all resistors are common metal films, 0207 size
caps - dimensions are easy, if you print pdf "parts placement" in exact size (100%), then all you need is ruler to measure OD and pads raster
etc
if in doubt, ask
all resistors are common metal films, 0207 size
caps - dimensions are easy, if you print pdf "parts placement" in exact size (100%), then all you need is ruler to measure OD and pads raster
etc
if in doubt, ask
May I lower R3/4 combo to approx 3ohm for additional CCS to power NP 6-24 crossover from the pos rail.? It requires 120mA and if I keep spare CCS to the 80mA I create no more heat in M1. Is the rest of the circuit happy with that?!
so, Iron Pre SE - How to wire AVC instead of [regular attenuator and output autoformer]
(Patrick, you can put link to in post #1)
Does this wiring apply to the 2021 pcb as wellso, Iron Pre SE - How to wire AVC instead of [regular attenuator and output autoformer]
(Patrick, you can put link to in post #1)
My iron pre kit is here, looking forward to getting started. Been trying to find a build is there one?
Does this wiring apply to the 2021 pcb as well
certainly; changes between two iterations are (sort of) minimal, strictly auxiliary circuit
Been trying to find a build is there one?
not yet; you'll need to read schematic

pretty much everything you need to know (from build guide) is already covered in this thread with pictures
Ok thanks ,my mono pair of avc only have 3 tags- in, out and ground so i guess i just keep to the drawing. How much gain will i get?
everything the same as shown in #2113
if you connect signal from buffer to your AVC's "IN" pad, you'll not have any gain
if you connect signal to switch (or directly to autoformer pin) contact of -3db, you'll have +3db gain, when AVC set to max
if you connect signal to switch (or directly to autoformer pin) contact of -6db, you'll have +6db gain, when AVC set to max
if you connect signal to switch (or directly to autoformer pin) contact of -9db, you'll have +9db gain, when AVC set to max
that you need to determine physically, but it's easy:
-3db switch contact is one connected to output when switch is in "max-1" position
-6db switch contact is one connected to output when switch is in "max-2" position
-9db switch contact is one connected to output when switch is in "max-3" position
again - reason why I was recommending cheapest Slagle package is simple - that version is having switching kept simple, just dealing with output node
all costlier iterations he's having are having combined switching, dealing both with output node and input node, to get greater number of positions
I know that I can deal with any iteration to include it in IPre package (enabling gain setting, that's the catch), but I'm really not in the mood to see have I necessary info, then wrestle with preparing necessary documentation to post here, taking in account that maybe one or none of Greedy Boyz is actually needing that
disclaimer - I can't remember what's switching arrangement for his most expensive version (zillion positions with Elma switch(es), ready made package) even if I had it on my bench, assembly done for friend
edit: pics of your actual AVC could help me to help you with precise tips
if you connect signal from buffer to your AVC's "IN" pad, you'll not have any gain
if you connect signal to switch (or directly to autoformer pin) contact of -3db, you'll have +3db gain, when AVC set to max
if you connect signal to switch (or directly to autoformer pin) contact of -6db, you'll have +6db gain, when AVC set to max
if you connect signal to switch (or directly to autoformer pin) contact of -9db, you'll have +9db gain, when AVC set to max
that you need to determine physically, but it's easy:
-3db switch contact is one connected to output when switch is in "max-1" position
-6db switch contact is one connected to output when switch is in "max-2" position
-9db switch contact is one connected to output when switch is in "max-3" position
again - reason why I was recommending cheapest Slagle package is simple - that version is having switching kept simple, just dealing with output node
all costlier iterations he's having are having combined switching, dealing both with output node and input node, to get greater number of positions
I know that I can deal with any iteration to include it in IPre package (enabling gain setting, that's the catch), but I'm really not in the mood to see have I necessary info, then wrestle with preparing necessary documentation to post here, taking in account that maybe one or none of Greedy Boyz is actually needing that
disclaimer - I can't remember what's switching arrangement for his most expensive version (zillion positions with Elma switch(es), ready made package) even if I had it on my bench, assembly done for friend
edit: pics of your actual AVC could help me to help you with precise tips
OK, so you have -3, -7 and -10db positions
you need to find those taps physically, same logic applies as
you'll hardly decipher that with ohmmeter, considering that Rdc of winding is low, so you can't differentiate direct contact of switch to resistance of windings - best way is if you have same switch spare so you can measure on it, or simply reading datasheet of switch
there are other ways, all really easy, you can use any sort of signal generator connected to AVC yadayada ....... sole important thing is that you have proper mental image of AVC itself and its function.....
you need to find those taps physically, same logic applies as
-3db switch contact is one connected to output when switch is in "max-1" position
-6db switch contact is one connected to output when switch is in "max-2" position
-9db switch contact is one connected to output when switch is in "max-3" position
you'll hardly decipher that with ohmmeter, considering that Rdc of winding is low, so you can't differentiate direct contact of switch to resistance of windings - best way is if you have same switch spare so you can measure on it, or simply reading datasheet of switch
there are other ways, all really easy, you can use any sort of signal generator connected to AVC yadayada ....... sole important thing is that you have proper mental image of AVC itself and its function.....
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radio silence?
no one?
working?



Just putting power to the Pass Bedroom Lab Pre's now. 😢 I'm way too slow for you!!!
I'm silent because I'm listening to my IP and enjoying every moment. Dug out and played an old memory - Deep Purple's Child in Time. The Hammond organ never sounded so good, but what struck me was the detail of the symbols for such an oldish recording. Love my IP. Thanx ZM.
The black album version has the better sound according to my ears when I compared the two (streaming).
Tonight I heard "Gaspard de la nuit". A very easy playable piano suite composed by Maurice Ravel.
Tonight I heard "Gaspard de la nuit". A very easy playable piano suite composed by Maurice Ravel.
I'm silent because I'm listening to my IP and enjoying every moment. Dug out and played an old memory - Deep Purple's Child in Time. The Hammond organ never sounded so good, but what struck me was the detail of the symbols for such an oldish recording. Love my IP. Thanx ZM.
Come taste the Band is fave LP of mine
for my preferences, that was absolute peak
but that's me - contrary to my gen, I was more prog and jazz than rock
now, logical, I'm Omni

...and all I want to hear is all Bach's Cantatas and Orgel on my unfinished Woden Aveburys. and A. Nurvanas. Bi-Amped! With Iron Pres.now, logical, I'm Omni
biamping is for you Youngsters
we Geezers, plain 2-channel amp, that's complicated enough

we Geezers, plain 2-channel amp, that's complicated enough

Vikings, taste?
see what you done of (now) Wakoo Albion ....... they were wakoo enough before you came .......

see what you done of (now) Wakoo Albion ....... they were wakoo enough before you came .......

So 60's....2-channel amp

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