Pumpkin preamp - ordered by Steen , official making thread

[Zen Mod]

Originally posted by steenoe
Guys, you are bored..... Here is something to have you listen up..
Since this thread has my name printed on it, I thought that you might want to see one of my fav. flies::::-) he-he Here ya go, take a look at the sweeping flow, that this fly has........Makes you want to throw it into thew current...... I am sold, Greame is, the question is, are you???? Yep, I dressed it......;-)

Steen

[Zen Mod]

Originally posted by mpmarino



.....

Even nicer to see your post

I just luuuuve this old fart

[Zen Mod]

Originally posted by lykkedk
ZenMod, I know that you can't remember the open loop gain / close loop gain, of the circuit, but is it possible that it can be explained howto calculate it.

lykkkkkgreedydanske

it's hard to please everyone ;

with phono section as that - you can't have all ;

I told you before - you can't go near OLG without sacrifices , just beacuse everything is matter of compromises ;

near OLG , you loose both freq extremes ( not that both are necessary)

what you also loose is amount of X feedback ;

anyway - it's up to you to choose what's best for your ears

in your boots - I'll toss both and F4 ( as a gift to Magura , just because he doesn't have them ) and make one nice toob system ...........



anyway - for test - desolder feedback resistors and measure OLG at 1KHz ; you can measure also OLG at 20Hz and 20KHz , while you are at it . I'm sorta short in time , because it will take few mnths that I make my own ; all I have in this moment is just one populated Shunty pcb.

let us know what results are

regarding calcs - I remember that my calcs aren't very near measured ; I'm primary toob guy - used to graphs and rulers ,along with calculator ; there must be something I missed for OLG calculus .... those dreky mnfctrrs of 3-7 legged fuses make so small and useless graphs

[Zen Mod]

Originally posted by dviswa
ZM, anybody,

C4/C5 & C11/C12 are the output caps, I know you have said use your fav. But, I do not have a "fav". I am thinking of using
Black Gate N 47mfd 50V available in partsconnexion for $10, bypassed with 1mfd Vishay MKP 416-420 available on Digikey for a buck.

Why 47mfd? Well, my pumpkin will also be doing double duty of a headphone amp. I thought a larger cap will help with lower impedance cans. Or is this not a good idea?

What do you guys think of this choice? Any other suggestions?

Thanks,
Dinesh

Dinesh ;

you package ( + ) , along with others is packed and ready to sending ;

I just kissed closed doors of post office today ;

seems to me that you found your fave caps

just go for it .

somewhere - in one of my useless OT threads - I mention that I tried with cans - with stock (4uF) output caps , cans's impedance was ...... both channels in parallel - so must be no more than 50 ohms........

to cut a ... sound was pretty decent , no flabbyness ....... blabla

think about decreasing output resistors to ~ 22E , from 47 as they are now ;

if needed - we can later try something simple - increasing Iq in output stage(s)

don't forget to take cans off the head , if BG's need little burning in

[mpmarino]

Originally posted by Zen Mod



I just luuuuve this old fart

If I'm an old fart, you're a stone age fart

[Zen Mod]

Originally posted by mpmarino


If I'm an old fart, you're a stone age fart

this time I didn't mean on you , but on Lucky Luke



ya aren't old fart , ya're CY

[Magura]

Originally posted by Zen Mod





this time I didn't mean on you , but on Lucky Luke



ya aren't old fart , ya're CY

Watch your mouth KK

Magura

[mpmarino]

To Mr. Magoo I'm a old fart. To Choky I'm a yungin'


Edit: Hows the pre amp building coming along

[Zen Mod]

Originally posted by mpmarino
To Mr. Magoo I'm a old fart. To Choky I'm a yungin'

yup - there is a big black hole between 34 and 40

Originally posted by mpmarino

Edit: Hows the pre amp building coming along

>De Niro<

"ya talkin' to me..........

ya talkin' to me ? "

[mpmarino]

Originally posted by Zen Mod



yup - there is a big black hole between 34 and 40






>De Niro<

"ya talkin' to me..........

ya talkin' to me ? "

Bingo! 37 is right in the middle


I was talkin' to the thread