yeah, what abbeyroad said, the old shumachers were the real deal,
bi fi, inter leaving, and reverse winding,
what sound are you after?
original tweed bassman keith richard style with the torched grill cloth and ciggy burns all the way into the yellow pine cabinet?
fender did interleave the windings, but later on, they just went kind of pri-sec cheap azz,
so, does the cheap azz sound ok?
sure, because bass does not radiate a lot of hf, who needs 3 db down at 40 k?
for bass?
well, you would be surprised at what the human ear can differ, so maybe we need that old transformer spec,
becuase you can always roll off extra program info if you neeed to, but once it is lost, you can not get it back, so better to have high end and not need it, thean the other way around,
root 2, remember that number, why?
1.4 is the number you divide the sec turns by to get the taps, 16 ohms, divide bi root 2, we have 8 ohms, divide by root 2, we have 4 ohms,
proof: 16 ohms divided by 8 ohms = z ratio of 2-1,
but z is turns squared, so to get turns, take root of....2!
so 120 turns for 16 ohms would be 120/1.4 = 85 turns for the 8 ohm tap , and
85/1.4 = 60 turns for the 4 ohm tap
for the pri, do we want screen taps for ul?
do we ant the flux the same?
what the flux has flux got to do with it?
changer the core size and you change the low end distortion.
MacIntosh uses a certain spec when designing their famous transformers,
something like 4% thd at 8 hz?
you want 4% at 4 hz? you have to double the core size.
you want Fender 4% at 20 hz?
use the stock core, a little grit in the bass is ok,
ever hear a bass thru a Mac amp?
sounds low and clean, like bob weir of the dead,
ok so keep the stock core if you want the same sound,
so we have the core, how many turns of what?
we got an honest 80 watts here, if we want to play 4 sets and drink 5,
we need a heat rise that makes the amp start to smell at last call,
so we need about 120 turns on the sec of #26,
what pri z do you want?
i like 3300 for some reason, 8)
so we need 120 tuns stepeed up to what?
square of the z ratio?
what is z ratio?
3300/16 = 206 and change,
root = 14 and change,
so 14 times 120 gives sec turns of 1680.
put a center tap at 840
winding structure?
put down about 200 turns of pri, wind it tight!
grab 4 sec wires #26 at once, wind 3 layers, 30 turns per layer,
lay down about 400 turns of #26 pri,
grab 4 sec wires and do the same thing you did the first time,
then about 400 turns of sec,
grab 4 sec wires and do the same thing you did the first time,
lay down about 400 turns of #26 pri,
grab 4 sec wires and do the same thing you did the first time,
now about 200 turns and we are done.
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.
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well, not quite. ???
now you have to figure out how to parallel all those sec windings! :'(
but boy, what a sound!
you want to reverse wind one of the pri windings, thats your bidness, i'm in trouble enuff already, hey Doc Hoyer of Audio Transformers in WI, whats up!
happy holidays and thanks mr authorized mac and marantz winder!
