shared-split cathode switch ?

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flemingmras
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Re: shared-split cathode switch ?

Post by flemingmras » Sat Mar 13, 2010 3:52 pm

rip wrote:I'm not sure, but do you know what type of switch it is? SPST DPST DPDT?

Rip
It's a SPDT.
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Re: shared-split cathode switch ?

Post by bluesbreaking » Sat Mar 13, 2010 6:09 pm

I'm not sure if I will want to cut up my amp quite yet since it's mostly stock, so I want to see if I really like shared cathode first. Do I just put a jumper between pins 3 and 8 of V1 to try it out?

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 14, 2010 11:26 pm

and disconnect pin 8 to the existing cathodes

rip

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Re: shared-split cathode switch ?

Post by Xplorer » Sat Mar 27, 2010 8:02 pm

hi !

now that i endly have some time to do this little mod, i'd like to ask a confirmation before ...
i don't understand why it wouldn't be more simple to just add a on off switch on the yellow wire between pin7 and the 0,68uf cap ... and leave alone the wire between pin3 and the 330 uf cap ...

or, and that's why i'm asking a confirmation , i'm totaly wrong about the switch configuration : what i understand is that in one case, the 330 uf and the 0,68 uf caps are connected to pin3 and pin7 respectively. in the second case, only the 330 uf is connected ( to pin3 ) .
am i wrong ?
why then having the 330 uf connected on a switch as in both cases it'd still be connected to pin3 ?


about the upper mid boost, i'm interested ; ) , but the 0,68 uf and the 820k are soldered on the same point on my superlad, not like this schematic, separated.

Thanks !

and what do the mustard caps add, according to you ? should i use the exact same values as with the sozo caps ? and about the carbon comp resistors, what does it add too ?

should i change some cap or some resistors if i go from EL34 to 6550 ?


rip wrote:I figure this might work

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:05 am

perhaps this will clear up the switching.
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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:07 am

in shared mode you are combining both cathodes from the tube socket together and using the 330uF. the 0.68uF is not connected to anything.

in split mode you leave them separate and each uses its own cathode cap.

Rip

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:10 am

Xplorer wrote:hi !

now that i endly have some time to do this little mod, i'd like to ask a confirmation before ...
i don't understand why it wouldn't be more simple to just add a on off switch on the yellow wire between pin7 and the 0,68uf cap ... and leave alone the wire between pin3 and the 330 uf cap ...

because you still need to combine the pin3 and 7 in shared, you could just run that wire to the same turret as the 330 but this saves wire.

rip

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:12 am

Xplorer wrote:hi !

or, and that's why i'm asking a confirmation , i'm totaly wrong about the switch configuration : what i understand is that in one case, the 330 uf and the 0,68 uf caps are connected to pin3 and pin7 respectively. in the second case, only the 330 uf is connected ( to pin3 ) .
am i wrong ?
why then having the 330 uf connected on a switch as in both cases it'd still be connected to pin3 ?

yep this is wrong see previous reply

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:14 am

Xplorer wrote:hi !
about the upper mid boost, i'm interested ; ) , but the 0,68 uf and the 820k are soldered on the same point on my superlad, not like this schematic, separated.

Thanks !

well here you are switching the 0.68uF cap in and out yours is always boosting the mids.

Rip

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Re: shared-split cathode switch ?

Post by flemingmras » Sun Mar 28, 2010 12:15 am

Um...don't you guys mean pins 3 and 8?
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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:18 am

Xplorer wrote:hi !

and what do the mustard caps add, according to you ? should i use the exact same values as with the sozo caps ? and about the carbon comp resistors, what does it add too ?

should i change some cap or some resistors if i go from EL34 to 6550 ?

I've not built my amp yet nor played with mustards enough to say but I'm sure searching will find this. People really like the Sozo's I will use them, the handwound ones are said to have more bandwidth and should be used on earlier plexis while the regular vintage ones are better for later circuits.

again search as I'm not sure what needs to be changed but I believe the screens and bias needs work if going from el34's to 6550

Rip

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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 12:20 am

flemingmras wrote:Um...don't you guys mean pins 3 and 8?

yep sorry. was just assuming what was being referenced was correct. 3 and 8

good eyes man
Rip

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Re: shared-split cathode switch ?

Post by Xplorer » Sun Mar 28, 2010 9:26 am

totaly understood now ! ; )
thanks...a lot.
Adrien

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Re: shared-split cathode switch ?

Post by Xplorer » Sun Mar 28, 2010 2:07 pm

Done !

i think i have to test it for more weeks , with my ears, but right now, i think i prefer the shared cathode setting, that's really great ! totaly worth it.
what is it gonna be with mustard caps now .... ; ) mmmmh !
For those who hesitate to get a metroamp, well ... you can't hesitate even a second, really not.

thanks for the help.
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Re: shared-split cathode switch ?

Post by rip » Sun Mar 28, 2010 9:17 pm

looks good man nice build

rip

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