Pumpkin preamp - ordered by Steen , official making thread

Re: Craziest Danske strikes again

Zen Mod said:
lookie lookie front plate

:rofl:

Yep, the frontplate was for Manu😀 Dont worry about the scratches and the general mess, I dont😎
This is just my testbed, but a new rearplate is in order anyways😉
"I'll be back"

🙂

Edit: lookie lookie, new testbed😀 Who the heck pulled out the trafo of that poor thing?? It contains a few handfull's of Toshiba J-fet's, including dual fets🙂 Also a bunch of mica cap's in there. Together with a very nice shielded and potted EI-trafo, isnt that a bargain for 50Euro's😉 The RIAA-part in upper right should be pretty good too.
 
jacco vermeulen said:


Each Yamster should be terminated (minus some pianos and the V-Max)
Even the most basic models contain gourmand items, we is the recycle bunch.

Pretty lights, the heatsink/plate of the shunty must be a hotpants.
Eh, LLcoolø is first taking it out, and then putting it back in ?

Jacco-man, ya too sharp😀 Yep the plate will be changed, when the Pumpkin enters its final home. Look at Rovsings picture of the LL heatsinks😀.

Okay seriously; my AX's were warm, so was the Pumpkin after adjustment. Plugged it in and ...... sound 😀 😀
Sound is very good! I have no idea what ZM did to the J310's, but the sound is crisp, delicate, liquid and very, very much in control! I never build a better preamp, considering all aspects.
The X'ed-CCS'ed CC'ed BosoZ might be a tad more warm in the sound, but it lacks the pinpointed soundstage and extreme details of the topend!! Soundstage is absolutely bang on....
The soundstage is very open, both in width and depth.
I bet its the Shunty thats on play!! I remember to have heard the same sort of openness with the NS10 on shunt's!!

🙂
 
jacco vermeulen said:
Q : which commercial pre-amps have shunt regulation ?

Me think a heatsink above 3C/W for the Shuntee is a hot cat on a tin roof.
OK in open air, with a cover on top Iznogood for the lytics.
Maybe if Rovsing keeps them high enuff.


don't forget that LL is cheapskate and he is feeding Shunties with 2x12Vac ...... heaven knws - Pumpylimpie is certainly starving , with negative-negative voltages :rofl: ....... countin' that Shunty have own losses of ~ 10V , each side .......

so - he doesn't need 'sinks ,at all ......... :devilr:
 
jacco vermeulen said:
Me think i has brain hemorrhoid again.
Don't comprehend the 12Vac part, what is lighting the led-string ?
You mean 2 times 12Vac in series, 24Vac ?


ya dumb dutchie ;

that means that Steen is in rotten shape - too much hangin' with Metaldanske, lately 😉

he isn't powered Pumpylipi at all ......... that's more like 2x0Vac .........

so - he need warmers for poor critters , not sinks .....
 
steenoe said:

... Sound is very good! I have no idea what ZM did to the J310's, but the sound is crisp, delicate, liquid and very, very much in control! I never build a better preamp, considering all aspects.
The X'ed-CCS'ed CC'ed BosoZ might be a tad more warm in the sound, but it lacks the pinpointed soundstage and extreme details of the topend!! Soundstage is absolutely bang on....
The soundstage is very open, both in width and depth.
I bet its the Shunty thats on play!! I remember to have heard the same sort of openness with the NS10 on shunt's!!
...

Thanks for the nice review, steen.

O, I cannot wait to complete mine!

(Still waiting for last missing caps)


🙂

(BTW : How is the sound of shunty alone? 😀 Just chock king ).


Manu
 
Zen Mod said:



ya dumb dutchie ;

that means that Steen is in rotten shape - too much hangin' with Metaldanske, lately 😉

he isn't powered Pumpylipi at all ......... that's more like 2x0Vac .........

so - he need warmers for poor critters , not sinks .....


Talking about starving pumpkins - since I'm going to use the 72VCT transformer and aiming for +/-30V after shunty - is there any other adverse effect on pumpkin other than the reduced max voltage swing?

The F4 is max +/-23v anyway? {ah that's 46v pp, and pumpkin is only 30vpp if single ended.?}
Anyway not going to need that much gain since my speakers are 93db/w in a really small room.

her shann
 
Ya guys are nutz😀 I am running 72VCT or said in another way (someone could be fooled with all ya'r nutty talk) 36-0-36 V AC:dodgy:
I dont think there is much ill effect from that, and dont blame my man, Magura, for it😀
My AX's sound like a totally new pair of poweramps, with the Pumpkin! They really gained some terrain, riding on this preamp😎
Lykkedk was right😉 It really does sound good.

🙂
 
jacco vermeulen said:
Q : which commercial pre-amps have shunt regulation ?

Me think a heatsink above 3C/W for the Shuntee is a hot cat on a tin roof.
OK in open air, with a cover on top Iznogood for the lytics.
Maybe if Rovsing keeps them high enuff.

The heatsinks get really warm. A few ventilation holes in the pcb would help in that respect. Just in case my crazy man, ZM, is gonna do a second run of boards😉 Raising the heatsinks to add a little airflow underneath will also help, ofcourse.
Running only 72VCT like me, helps too😉

Steen (with 2 dedicated preamps, specifically designed for him😀 )
How cool does it get?
 
jacco vermeulen said:
The super-shunty is Mr Stax Noro's brainchild.
Stax Ca-X,CA-Y, SRA-14S preamplifiers, DA-100 power amp, other stuff.

+ sheetdump of valve junk


Mr. Noro's shunt reg is example of elegancy , not as Shunty .......... :rofl:


this - last one - Shunty - is certainly more versatile ( with changing just few resistor values) and plain overkill .....

valve junk was ........ waaaaay before Mr. Noro's sand trap ......

anyway - give me OA2 , keep Noro or Shunty for your self ;

any time

:clown: