Iron Pumpkin(s) and other smaller vegetable animals

[koja]

did you prep Papa for us asking "how many Passes?" (on Zen scale)?

p.s. pls do not forget to look at my D150 (for bal input) question at some point. A LOT of Iron waiting in that one to be heard

 

[Zen Mod]

I believe Papa is more than prepared , whatever we came on to ask him

regarding D150 ...... oh boy , even if I know , I'm simply always again surprised to see - boy , they were on some really baaad weed , for almost every new construction .....



will do , these days ... I really need some inspiration to solve that input puzzle ...... don't want to solve it as Gordian Knot

 

[sov]

I better ask here. Can Pumkin Iron SE work with F4 and 100+dB speakers?

 

[Zen Mod]

say that your source is having true 2Vrms

IP SE is having settable gain of 0, +2, +4, +6, +8db

which means there can be (8db setting) 2Vrms x 2.5V/V=5Vrms at output of IP

then P=Urms^2/Rload

P=5^2/8=3.125W/8R

double that on 4R load

interesting , I have same situation in my workshop , SPL being more than enough even on my 16R RCA LC1 , they not being hysterically efficient ..... around 91.5db/W/m ...... so being driven with no more than 1.6W

I'm burning around 160W of heat in Papa's Koan , for effective 1.6W per channel

 

[sov]

Interesting! Would it be similar with a 1:1 transformer on M2?

 

[Zen Mod]

exactly the same

though , if you don't need gain in M2 , just skip xformer ........ input buffer ditto driving OS

btw. finally got these small pcbs , as missing link .....

someone's Pumpies are packed in this very moment

 

[sov]

I probably could bypass the buffer as well?

 

[Zen Mod]

remove R5, C1 also

you can do without buffer if preceding stage is having appropriate Cojones

Rin of OS is sorta 22K-ish , but better to have proper control in front of it

 

[sov]

Front like iron pumkin

 

[Zen Mod]

oh

that's capable one .......

biiiiig Cojones

 

[Zen Mod]

Just posted : Iron Pumpkin, another one | Zen Mod Blog

plenty of pics

 

[Zen Mod]

I believe this pic is more illustrative :

 

[gary s]

ZM, you need to squeeze some more relays into the design somehow.

What is the Zen Turtle can we ask?

 

[dBel84]

Iron octopus more than pumpkin

 

[Zen Mod]

ZM, you need to squeeze some more relays into the design somehow.

........

yeah ..... just 24pcs for SE and just 48pcs for balanced

plus 5pcs for each channel as selector , and additional one per channel for balanced , as switch for SE in/Bal out mode

so , that will be ........ 24+5+5 for SE , 48+6+6 for Bal

........

What is the Zen Turtle can we ask?

best to read from #1 of this very thread

 

[gary s]

Thanks ZM, should have looked from the start of the thread - hell you have put some work into this piece of art and many hours obviously. I hope it rewards you with glorious sound by the way and is a big improvement over all previous preamps you no doubt have built.

 

[gary s]

Oh, and by the way, we wont ask you how much this has cost you up to now for a full working prototype - the mind boggles.

 

[wtl]

ZM, I have made a start on my Pumpkin (At Last).
Many Thanks.
Steve

Progress Pic.

 

[Zen Mod]

put them Donuts somewhere in front

either on side plates or front plate

lesser evil to route mains wires (screened , please) to them than to have them at back , near input wires ......... and then you can move channel pcbs all the way back

 

[Zen Mod]

Oh, and by the way, we wont ask you how much this has cost you up to now for a full working prototype - the mind boggles.

thank you ... yes, I am really proud Papa of this one

numerous prototyping steps , struggle to source everything I wanted to try and compare

but , that's normal .... when you are building just one specimen for yourself , it's easy - I have pretty big stash of zillion interesting parts , but I decided to make a product , made with elements in current production , possible to have them any time I need them

sorta rollercoaster , but well worth , in the end