Re: Sweep me off....
steenoe said: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
Re: Re: Sweep me off....
I just luuuuve this old fart
mpmarino said:
.....
Even nicer to see your post
I just luuuuve this old fart
lykkedk said: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
dviswa said: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
Re: Re: Re: Sweep me off....
If I'm an old fart, you're a stone age fart
Zen Mod said:
I just luuuuve this old fart
If I'm an old fart, you're a stone age fart
Re: Re: Re: Re: Sweep me off....
this time I didn't mean on you , but on Lucky Luke
ya aren't old fart , ya're CY
mpmarino said:
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
Re: Re: Re: Re: Re: Sweep me off....
Watch your mouth KK
Magura
Zen Mod said:
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 said: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
mpmarino said:
Edit: Hows the pre amp building coming along
>De Niro<
"ya talkin' to me..........
ya talkin' to me ? "
Zen Mod said:
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
mpmarino said:
Bingo! 37 is right in the middle
.......
so - you are nothing else than , poking from hole here and there
Zen Mod said:
you package ( + ) , along with others is packed and ready to sending ;
Thanks a lot.
Thanks, I will.Zen Mod said:seems to me that you found your fave caps just go for it .
OK, anything else I should be changing?Zen Mod said: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 ;
Zen Mod said: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
I was wondering about it too. Let's say I want to double the Iq, what values should I be considering?
dviswa said:
............
Let's say I want to double the Iq, what values should I be considering?
roughly speaking .........
halving all mosfet source resistors ;
so - R11 & R16 to 15~18E , R12/R26 & R17/R28 to 330//240E (all that in Pumpkin)
so - that also need changes in Shunty - besides xformer capable to give ~ 82Vct/800mA minimum for stereo , all heatsinks twice thermally capable ( that applicable for Pumpkin too ) and decreasing R7/R7a to 2E4 (Shunty)
in that case you'll double present current hunger of Pumpkin/Shunty combo , which is ~140mA/channel
so - you'll have preamp drawing 82V x 0,28A x 2 =46VA ......
more than some hifi DrekMKXX SE^2 amps
anyway - it's up to you to choose what's best for your ears
This is not a problem... no difference between soundsonics of 10xgain and 20xgain
Actually, i am not having trouble, with the gain anymore, it was just an idea i have, that maybee someone else was gainhungry like me too ! ... I allready adjusted the gain to my need's... I see ofcause that the phono-pre, can't be playing as loud as i would like it to, with a gain of 20x, but it's good enough for now.
I realise, that this is not the right place to ask, about howto calculate such thing's as X-feedback OLG, CLG... etc... seem's that anyone else but me, understand's this.
I am going to study these technicue's in future... regarding gain/loop etc... that i don't understand quite well... And maybee (can't promise) i will try the meassuring ZenMod suggested.
Anyway, in next few day's.... sneakpreview of my inputselector
Greeadylykkedk.... yes i am
Jesper.
jormajj said:The Pumpkin and Shunty PCBs arrived today, Thanks Choky and OLy !
Great looking boards
Here are some examples of heatsink types fitting on the PCBs
( 50 mm high):
Fischer
SK81-50 SA
SK75-50
Austerlitz
KS100.3-50
KS32.1-50E
jormajj
tnx jormajj
vitalstates said:I wonder...did steen ever get caught with his flies undone???
the real question, choky OLD chap....my F4 sings with my squeezebox and I can only get the volume up half way....this means that thinking about pumpkin is idling away the time for no good reason???
Ed
well........ you have schematics , cookbook, few hysteric threads for easy reading for fun ....... what are you waiting?
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