Iron Pumpkin(s) and other smaller vegetable animals

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#781
Click expand, then view attachment to see "before" pic.

Please forgive my poor manners for not properly introducing "The Windbags" previously.

From r to l:
Baritone - Larry Fine
Lead - Moe Howard
Tenor - Curly Howard

AKA "The Three Stooges"
 
#786
Nelson Pass said:
More recently his friend Vladimir was visiting California
and brought me ZM's later, more polished effort, with such
wife pleasing features as a chassis, remote control (and
personalized display greeting) which stars in the main
system upstairs, driving a pair of Beasts (of a thousand
Jfets) and SR-1 speakers.

First and foremost, it's a great sounding preamp. Excellent
tonal balance, imaging and transparency. When I began to play
some vinyl, I suddenly was able to hear something new, a flaw that
turned out to be the anti-skating, re-adjusted by the cleaning lady,
bless her heart 🙂

After that I spent many hours enjoying this piece, I would say the
culmination of ZM's journey into magnetism.

And lots of gain, more than my other preamps, and the ability to
drive the input capacitance of the Beasts and other follower
amplifiers without the need for additional front end gain circuits.

It has a permanent place in my system.

Here's the porn and glory, showing the preamp along with the front
panel display and also these new smaller versions of the 1K Beast.
Click to expand...
Is this available as a DIY?
 
#787
Original Swap Meet thread:

Zen Mod

Thread 'Iron Pumpkin preamplifier(s) kits'

Well , everything explained and shown in technical thread :

Iron Pumpkin(s) and other smaller vegetable animals , but be aware that latest and final iteration of electronic part of package (main difference being JFet buffer instead of Diamond ) is shown in Iron Pumpkin(s) and other smaller vegetable animals, Tips 'n' Tricks thread

on sale are several options :

1. Iron Pumpkin SE (yup , that one being for RCA inputs/outputs) ,consisting of :
-Iron Turtle SE AVC , as assembled and tested unit (two irons on one common pcb ), rotary switch...

Things have evolved a lot since then…Logic etc.

Depending on MZM’s backlog, supplies, Serbian Postal status and possibly mood 😈you might be able get one.

Original building thread here:

Zen Mod

Thread 'Iron Pumpkin(s) and other smaller vegetable animals, Tips 'n' Tricks thread'

Well, origin thread is here : Iron Pumpkin(s) and other smaller vegetable animals

If nothing else, read at least first several posts on linked page , to grasp enough info about concept itself.

This one having two purposes :

-placing all necessary info about final iteration,

-trying to layout clearer picture of what's fuss about,

-with edits of this first post - making comprehensive list of tips and tricks and funny fine details , and answering on any clever or dumb question you'll possibly have ......either here or further in thread

(3 purposes then , not two :rofl...
 
#788
Photos of each kit?

1741449685696.png
 
#798
Want to be said:
🙄Purpose of TFT screen and remote control? To watch cartoons?
Click to expand...

Read thread you originally wrote in ( evidently Mods moved last several posts from there to here) and you'll see Plankey, which I concocted in situ in 2019, while visiting Papa at Sea Ranch, along with 2 other Amigos; for the record, I'm Dumbest of 3.

Some funny pic here: https://www.zenmod.in.rs/?s=Mighty+ZM+Californication+2019&numberposts=5&results_hide_fields=

when Papa heard first tune through Plankey, he said just one sentence, which I clearly still remember "This is very nice retirement plan" ........ and while I was still digesting that sentence in my not so American English brain, he said another one: "But you must make it fancy".
OK, I digested first sentence, then I asked for clarification ....... which he gave - it needs to be posh, with screen and remote....... and then you can name your price.
In last several years, I started taking in account other lessons Pa is freely giving, not just technical ones; so, besides being smart Engineer, our Pa is extremely clever in all things market.
There are so many layers I'm certainly not aware of, but there are more than enough I realized after getting all those free advices ..... what all factors are in producing successful product.

Anyhow, to cut a story short - after Papa's advice, my reply was typical ZM Omnicocky - don't wanna make it posh, it's Move your Butt device!
But, after some thinking, I realized that Gray Beard is not Gray without a cause, so if I'm ever to get some of that (cause) better to leave cockiness aside , learn some Arduino and do my homework

so that's it.

as it is, last iteration of IPumpkin is TFT/remote/encoder controlled thingy, having 28 volume steps (2db each) where 24th is 0db and 28th is +8db of gain
it can be still got as governed with physical rotary switches, and that option is 24steps, with settable gain (0db, +2db, +4db, +6db, +8db) through jumpers on AVC

it's probably convenient to paste some info (I have from before) here (anything price related best trough PM):


..................Anyway, you can see it here, if you already didn't:


Plenty of pics and some of them of final revision, as shipping, here:
https://mega.nz/file/qZ1TFY7b#eP8bd1oAz-ZZUBp5jhxBivDDCaYlmnRVqLkeAWosGKE


Electrically - main circuit is presented in most recent thread about IP:
Zen Mod

Thread 'Iron Pumpkin(s) and other smaller vegetable animals, Tips 'n' Tricks thread'

Well, origin thread is here : Iron Pumpkin(s) and other smaller vegetable animals

If nothing else, read at least first several posts on linked page , to grasp enough info about concept itself.

This one having two purposes :

-placing all necessary info about final iteration,

-trying to layout clearer picture of what's fuss about,

-with edits of this first post - making comprehensive list of tips and tricks and funny fine details , and answering on any clever or dumb question you'll possibly have ......either here or further in thread

(3 purposes then , not two :rofl...

Only later I decided to make it all on one big motherboard




There is difference to video - using micro sized Fujitsu Takamisawa (FTR-B3CA024Z) relays, instead shown (RY-24W-K) mini relays - due to availability situation I was forced to make that iteration too



Anyhow, both series of relays are having same quality contacts , so difference is purely in package



Attenuation is 24 steps of 2db, so -48db



Gain is settable to 0db, +2db, +4db, +6db, +8db - simple jumper positioning, on AVC module



Available as fully SE and as Balanced

Take in account, when speaking of balanced preamp, that +8db setting can be extremely heavy load for (one) buffer when used as SE IN - BAL OUT, if Rin of following amplifier is any tougher; all lower gain settings are not critical in any scenario.



Both options having 5 inputs, in balanced arbitrary number of inputs settable as SE



Usual way for balanced is having additional set of SE outputs, both bal and SE operational in same time



Some elementary info about kits (what you get for your Greenies) here:
https://www.diyaudio.com/community/threads/iron-pumpkin-preamplifier-s-kits.311916/ ,
even if for initial version, and I'm not delivering electronics or AVC separately anymore.

Note: I forgot who was in case, but I know that at least one Greedy Boy did reach Modushop and they did all milling work for fascia for their appropriate case (Slim Line 03/280 3U 10mm, their No.1NSL03280N).
I'm inlcuding/sending all files (sketchup. screenshots, pdf, some CAD formats) for CNC work on fascia and back plate with kits, also packing most tricky part - TFT perspex protective window (fascia insert).
That one can be cumbersome for production, some metal working shops don't like to work with plastics.



************
addition as of March 2025; no more gain setting through jumpers; number of steps changed to 28, each 2db, where 28th is +8db position
 
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