Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Jatchley on November 02, 2020, 09:26:16 pm

Title: how do you wire a 3 way switch to stack caps in parallel?
Post by: Jatchley on November 02, 2020, 09:26:16 pm: switch wiring makes my head spin. idk why. but i want to know if im right in thinking i need a DPDT ON-ON-ON is this correct? and how do i wire it??? but for context take the TMB tone stack. lets say i have a .02 mid cap.

so how do i make the stock value the down position for a total of .02
then how do i make the middle position stack a .01 cap in parallel for a total of .03
then how do i make the top position add another .01 or .02 in parallel for .04 .05

i'm trying to make a mid tilt switch.

edit:
i think i figured it out. i need an OFF-ON-ON+ON switch specifically in that order. which is proving a little difficult to find as a short bat but heavy duty. still hunting though. and i think in my searches to find a mod or anything like this i saw something about needing a coupling cap to block dc before the bright switch and preamp anyone know anything about this and want to elaborate if that applies to just stacking caps? also a friend told me there are resistors to wire on the switch to cure the popping sound of instating the parallel cap but didnt elaborate anymore than that? anyone know about this?
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: vampwizzard on November 02, 2020, 11:24:22 pm: Id honestly just use on-on-on switches with different values.. a .02, .033 and .04 should all be available to you , or do a rotary style switch like on Sluckeys AC15 lite: http://sluckeyamps.com/hammond/hammond_ao39.pdf (http://sluckeyamps.com/hammond/hammond_ao39.pdf)
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: Jatchley on November 03, 2020, 12:10:37 am: Quote from: vampwizzard on November 02, 2020, 11:24:22 pm
Id honestly just use on-on-on switches with different values.. a .02, .033 and .04 should all be available to you , or do a rotary style switch like on Sluckeys AC15 lite: http://sluckeyamps.com/hammond/hammond_ao39.pdf (http://sluckeyamps.com/hammond/hammond_ao39.pdf)

OH! that makes sense! nice. sluckey is awesome too. that rotary switch is cool. i'm also building matched pultecs right now (been waiting since may for my trafos) and have been wondering about how rotaries are wired up too.

anyway i will try to do it with the on-on-on that way sounds nice. so i need a shorting on-on-on dpdt switch?

i think im still confused on how to wire an on-on-on switch without mixing 2 of capacitors in the middle position.
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: sluckey on November 03, 2020, 04:11:24 am: Exactly what you asked for...
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: sluckey on November 03, 2020, 08:15:49 am: You can also use this short/fat bat switch...

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=C%26K-7211&_sacat=0
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: Williamblake on November 03, 2020, 01:56:50 pm: Quote from: sluckey on November 03, 2020, 04:11:24 am
Exactly what you asked for...

I use an on-off-on switch to do something like that which has the positions sonically out of order so i would really like to know where you got that switch or how it is called. Making this my first Hoffman order.

//
https://hoffmanamps.com/MyStore/perlshop.cgi?action=template&thispage=Switches&ORDER_ID=304283967

https://el34world.com/charts/SwitchDPST.htm
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: sluckey on November 03, 2020, 02:08:38 pm: The info is in the pic. Just click the "switches" link below this message.

Or go to AES for the same switch...

https://www.tubesandmore.com/products/switch-carling-toggle-dpst-3-position-play-stdby
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: Williamblake on November 03, 2020, 02:36:54 pm: Dpst-3-position-play-stdby

Thanks, i really thought there is no such switch. Also the Hoffman webshop makes me feel illiterate.
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: sluckey on November 03, 2020, 03:00:57 pm: It pays for this forum.
Title: Re: how do you wire a 3 way switch to stack caps in parallel?
Post by: vampwizzard on November 03, 2020, 05:34:47 pm: Quote from: sluckey on November 03, 2020, 03:00:57 pm
It pays for this forum.

and his prices are roughly within 1-5% of anywhere else, you wont get faster shipping nor better service. buy everything you can from the store.