As title sez - one name, two preamps. Major thingie is AVC Volume attenuation and, sheer luck involved, some free (magnetic) voltage gain.
Reason for 2025 presentation - to show present state (hopefully no further changes
), while there are two preceding threads where you can refresh memory.
Threads:
There is also Papa's tongue-in-cheak thread, I'll say no more, nudgenudge, say no more
Iron Pumpkin SE, logically, being for single ended signal arrangement, so 5 RCA inputs, and one RCA output; I'm usually mounting doubled RCA outputs, wired simply in parallel.
Iron Pumpkin (no suffix), balanced signal configuration, any number of 5 inputs can be arranged as (permanently) SE/RCA, balanced output can be wired to one or two (parallel) XLRs, or one XLR and (parallel) RCA
2025 iteration, besides major physical change to Big Motherboard, is also having altered arrangement of Iron Turtle (AVC) module,e with (new) 28 steps arrangement.
Step 24 is 0db,
step 23 down to step 1 are each -2db,
step 25 to step 28 are each +2db.
So, ranging from -46db to +8db. Previous arrangement, with 24 steps and jumpers for (permanent) gain set stays as solution for kit/finished preamp with physical/rotary switches controls.
And, yes, now there is a choice between Metglas and Finemet cores; what's the difference between two - pretty much the same as between Cinemag normal nickel and CInemag high nickel - normal isn't much worse than high nor high is much better than normal........ but when you shoot, you usually shoot for better sleep
Dazzling, Shiny and Overwhelming characteristics speech: Fully dual mono (custom made 20VA Donut for audio circuitry is having separate secondaries for channels; custom made 10VA Donut feeding all things Logic and switching), ultragigamega shunt regs, OhYeah! Toshiba For Audio JFets serving in buffers, precious Fujitsu relays for everything what's switched, volume attenuation as explained above, yadayada.......
Button on front, fiddle left-right to set volume, push for incremental cycle through inputs 1 to 5.
Fancyschmanzy remote having same functions, plus mute/unmute buttons.
3.5'' TFT as Eye Candy, Tesla writing for ZML Greetings, then Led Zepp font for functional screen.
Reason for 2025 presentation - to show present state (hopefully no further changes
), while there are two preceding threads where you can refresh memory.Threads:
There is also Papa's tongue-in-cheak thread, I'll say no more, nudgenudge, say no more
Iron Pumpkin SE, logically, being for single ended signal arrangement, so 5 RCA inputs, and one RCA output; I'm usually mounting doubled RCA outputs, wired simply in parallel.
Iron Pumpkin (no suffix), balanced signal configuration, any number of 5 inputs can be arranged as (permanently) SE/RCA, balanced output can be wired to one or two (parallel) XLRs, or one XLR and (parallel) RCA
2025 iteration, besides major physical change to Big Motherboard, is also having altered arrangement of Iron Turtle (AVC) module,e with (new) 28 steps arrangement.
Step 24 is 0db,
step 23 down to step 1 are each -2db,
step 25 to step 28 are each +2db.
So, ranging from -46db to +8db. Previous arrangement, with 24 steps and jumpers for (permanent) gain set stays as solution for kit/finished preamp with physical/rotary switches controls.
And, yes, now there is a choice between Metglas and Finemet cores; what's the difference between two - pretty much the same as between Cinemag normal nickel and CInemag high nickel - normal isn't much worse than high nor high is much better than normal........ but when you shoot, you usually shoot for better sleep
Dazzling, Shiny and Overwhelming characteristics speech: Fully dual mono (custom made 20VA Donut for audio circuitry is having separate secondaries for channels; custom made 10VA Donut feeding all things Logic and switching), ultragigamega shunt regs, OhYeah! Toshiba For Audio JFets serving in buffers, precious Fujitsu relays for everything what's switched, volume attenuation as explained above, yadayada.......
Button on front, fiddle left-right to set volume, push for incremental cycle through inputs 1 to 5.
Fancyschmanzy remote having same functions, plus mute/unmute buttons.
3.5'' TFT as Eye Candy, Tesla writing for ZML Greetings, then Led Zepp font for functional screen.
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....... Now, Iron Pumpkin funny black and white technicals:
Attachments
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Iron Pumpkin schm 1 of 11.png -
Iron Pumpkin schm 2 of 11.png -
Iron Pumpkin schm 3 of 11.png -
Iron Pumpkin schm 4 of 11.png -
Iron Pumpkin schm 5 of 11.png -
Iron Pumpkin schm 6 of 11.png -
Iron Pumpkin schm 7 of 11.png -
Iron Pumpkin schm 8 of 11.png -
Iron Pumpkin schm 9 of 11.png -
Iron Pumpkin schm 10 of 11.png -
Iron Pumpkin schm 11 of 11.png
Will not post schm for Iron Turtle (AVC) module, who needs to see lines connecting zillion pads and zillion relays .......
Same for TFT module, nothing funny there
Enough visual info from following pics
Same for TFT module, nothing funny there
Enough visual info from following pics
Recently made Iron Pumpkin SE (No.15) pics
That one presently happy singing in Canada.
Phone cam, so be it.
That one presently happy singing in Canada.
Phone cam, so be it.
Attachments
Visual differences between SE and Bal are, against what you see above, is another pcb deck in Iron Turtle, 2 windings per core, arbitrary number of XLR and RCA back
So, as funny facts:
SE comprised 39pcs of tiny Fujitsu relays, while Bal is having 68pcs
SE is having 2*2000 turns of 0.2mm Dia wire, 2*25 taps, while Bal is having 4*2000 turns of 0.2mm Dia wire,, 4*25 taps
Muses chip is definitely more handy and convenient
So, as funny facts:
SE comprised 39pcs of tiny Fujitsu relays, while Bal is having 68pcs
SE is having 2*2000 turns of 0.2mm Dia wire, 2*25 taps, while Bal is having 4*2000 turns of 0.2mm Dia wire,, 4*25 taps
Muses chip is definitely more handy and convenient
