Pumpkin preamp - ordered by Steen , official making thread

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carpenter said:
Choky,

Paypal says funds have been sent. I don't know how long it takes for them to show up in your account. Let me know if there's a problem.

John:)


reply sent to ....... (wait - I must see) .............. your musical mail addy .


HU Paypal is fast ;) even if I'm not in HU ........... major PITA , Serbia will never be covered with Paypal :mad:
 
Official Court Jester
Joined 2003
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carpenter said:


Maybe you can move? You can always come here and have Bush for your president...he'll even ease-drop on your phone conversations and emails--just to make sure that you're getting a quality signal, of course! ;) :D


well .......... (mods- this is not politics,please) - changing one drekhead for another isn't always good solution ........ drekhead is drekhead, smaller or bigger ...........

hehe - what can I do when Papa doesn't want to adopt me , disregarded my application for cleanin' lady at Pass labs etc .........

seems that I'll never make my American Dream .......

so - I must live ZM's dream ;)

besides - living in US of A will result in my endless searching at junkyards for anything Altec signed ......... not exactly normal life , don't you think :devilr:
 
My town still has a metal pile that can be deposited to and removed from at will. It is a true gem. A few weeks back I found an old reel to reel player with a nice single ended triode amp in it. It is always amazing to me what americans will throw away. Fortunately for me the metal pile has somehow instilled a good attitude as people will often try putting things on the curb with a free sign before they throw it out.

Choky, I think you would be not as alone as you may think in searching for all things altec.

DaveM
 
Hi ...

ZenMod, when you tell to place voltmeter, at outerpin of C4 / C5, you mean at the point, where R13 meets C4(-out) , and where R18 meets C5 (+out) right ? - seem's a little hard to understand 100% (at least for me ;)). Well my pumpkin have been playing for several week now., but i will recheck the adjustment's when i somehow in future get chance to put it in box :)

C4 / C5 is the 10uF outputcap's you're meaning in the assembly-instruction's right ???

Jesper.
 
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lykkedk said:
Hi ...

ZenMod, when you tell to place voltmeter, at outerpin of C4 / C5, you mean at the point, where R13 meets C4(-out) , and where R18 meets C5 (+out) right ? - seem's a little hard to understand 100% (at least for me ;)). Well my pumpkin have been playing for several week now., but i will recheck the adjustment's when i somehow in future get chance to put it in box :)

C4 / C5 is the 10uF outputcap's you're meaning in the assembly-instruction's right ???

Jesper.

let me see ........

C4 and C5 from Pumpkin schematics ;
outer pins - physically outer on pcb , far left and far right side ......

I'm clearer now?

:D
 
C4 and C5 from Pumpkin schematics ;
outer pins - physically outer on pcb , far left and far right side ......

Yes Yes :D I know, i thought it over today, and see what you mean, regarding the placement of the output cap's...

I have attached a schematic, with 3 grey spots on, pointing on the meassuring point's, are they located the right places on schm. ???

Jesper.
 
Good ZenMod.... Then things will work for dummies (ahh like me ???) :D too !!!

Btw... I use a 10k stereo alps pot on input, you somewhere in the past mentioned something about what's fit your'e source best... Well i donno what impedance my DDDAC / PearlPhono have, so do you have any good suggestion, for an allround pot... meaning values both for stereo + eventually an balanced one. Maybee this could interest someone else too :D ... Anyway, keep up good work ...

Damn... i haven't got much time listning to dreky... and finishing up thing's - Right now i am designing an inputselector, with 3 unbal RCA input's + 1 balanced input + balanced/unbalanced switch for output, for futureproof - all along with a switch, where you can switch between two toslink input's... All that must go into dreky :Pumpkin: too.

I was inspired to make this myself, looking at twistedpears darwin-input-selector btw:.. But this is way O.T. sry for that.

Jesper.
 
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lykkedk said:
Good ZenMod.... Then things will work for dummies (ahh like me ???) :D too !!!

Btw... I use a 10k stereo alps pot on input, you somewhere in the past mentioned something about what's fit your'e source best... Well i donno what impedance my DDDAC / PearlPhono have, so do you have any good suggestion, for an allround pot... meaning values both for stereo + eventually an balanced one. Maybee this could interest someone else too :D ... Anyway, keep up good work ...

well - did you saw AR2's solution - two Black Widows (AKA Blue Velvets ;) ) , each stereo 50K pot ?
one per channel, so you have in same time balance too ....
that variant is both marked as good and also as bad , depending which personal preference is in question.....
anyway - 4 channel ALPS aren't so expensive - I think somewhere in range of 40 Euro ............... look HERE ..... that's my friend from Geek toob forum ......

I presume that you don't want Magura San to make eeeny weeeny attenuator for you , except if you have spare room just for them :devilr:

in any case - it's better to use as low attenuator value as you can, considering output impedances of your sources ; if sources are happy with 10K pot - then use 10K pot ; anyway Pumpkin is made with input impedance in that range ( remember value of resistors in both J310's gates )

Damn... i haven't got much time listning to dreky... and finishing up thing's - Right now i am designing an inputselector, with 3 unbal RCA input's + 1 balanced input + balanced/unbalanced switch for output, for futureproof - all along with a switch, where you can switch between two toslink input's... All that must go into dreky :Pumpkin: too.

I was inspired to make this myself, looking at twistedpears darwin-input-selector btw:.. But this is way O.T. sry for that.

Jesper.


my advice , and you know that I'm always willing for at least one :clown: is - use 4 channel volume pot , use only XLR connectors on input and also on output , use mini relays for input selector ( one double Takamisawa per channel input , so - when rely is not in use , both signal rails are grounded .

then - if you need to use nonbalanced source, just short gnd and minus leg ditto in cable XLR of that source

clear enough ?
I'm not sure ........ sometimes is hard to force my Engrish to follow what I want :clown:
 
clear enough ?

yeah, I think so... Your Engrish is better than you think :)

Ya know... I've been toying with the idea of building a separate input select/attenuator module with remote volume. Sort of what someone might build as a passive 'pre amp'( I always wondered how you could have a passive preamp?) Fully balanced input to output using whatever good components I have in the drawer. This would simply go between the sources and the pre. The actual pre would just be a box with 1 in and 1 out. Nice n' easy.


Why? you ask?
Maybe you didn't ask why- but I'll tell you anyway. Whenever I build a preamp circuit I'm finding that the most difficult part is the in selector and the attenuator - partswise. Also, it's hard to compare circuits because I never end up with the same type of attenuator. In doing this I would never have to scrape for an attenuator or input selector again - just keep using the same one.

Whadya think?
 
clear enough ?

Yep... allmost

in any case - it's better to use as low attenuator value as you can, considering output impedances of your sources ; if sources are happy with 10K pot - then use 10K pot ; anyway Pumpkin is made with input impedance in that range ( remember value of resistors in both J310's gates )

Are you telling me, that 5k is better suit's than a 10k one, if i got the choice ?

when rely is not in use , both signal rails are grounded .

Just soo, that any unused 'source' are grounded, when not in use ?

NICE answers ZenMod...

Jesper.