PARALLEL-CASCADE SWITCH

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JMPGuitars
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Re: PARALLEL-CASCADE SWITCH

Post by JMPGuitars »

pummpy wrote:
Sun 01/31/21 3:36 pm
Thanks , yes . Would like to do the Parallel-Cascade switch .
Main question i have is Do i mod the TMB input or The Low Hi input jacks as there are two there and TMB has one input jack .
I see the the Modded input jack goes to Pin2 V1 where my Hi Low input goes to that pin on V1 that has two input jacks . Do i eliminate both jacks if using that input and replace with one input jack as shown in mod ?
Hope i am making sence .
It won't work the way you want. A parallel / cascade switch means it changes the way the input V1 works, when V1 is used for only 1 channel.

Your build is using V1 for both channels, and the TMB channel already uses V2 as a cascaded gain stage.

If you look at a different circuit like a Lite 2b, you can see that V1 uses both halves for the same input(s). In that case, V1 can be used either as a parallel tube (V1a and V1b connected in parallel together), or it can be cascaded with one half of the tube being fed to the other.

If on the other hand, you wanted to modify the TMB channel so that the cascaded V2 could be switched to parallel instead, you could do that.

Another option would be to remove the TMB channel input from V1 and insert it on the first half of V2, and change the wiring for V2. This way the non-TMB channel could have a cascade/parallel switch. But this is probably more work than it's worth.

Take a look at a few different schematics (including the switch schematic in this thread) so you can see what parallel or cascaded tubes look like in the circuit.

Thanks,
Josh
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Re: PARALLEL-CASCADE SWITCH

Post by Bieworm »

Maybe the world is waiting for the tremolo TMB with an extra gain stage (cascade.. cathode follower,...) for the high gain guys 😉
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Re: PARALLEL-CASCADE SWITCH

Post by JMPGuitars »

Bieworm wrote:
Sun 01/31/21 5:04 pm
Maybe the world is waiting for the tremolo TMB with an extra gain stage (cascade.. cathode follower,...) for the high gain guys 😉
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Re: PARALLEL-CASCADE SWITCH

Post by pummpy »

Thanks again . I understand . Like to ask questions when not sure .
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Re: PARALLEL-CASCADE SWITCH

Post by geoff 1965 »

check out this plexi mk2 schematic, cascades normal channel into TMB channel.
18WattPlexiMkIISchematic5 (1).pdf
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Re: PARALLEL-CASCADE SWITCH

Post by pummpy »

That's the ticket rite there .
I Should have built the Trinity Mk2 👍
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Re: PARALLEL-CASCADE SWITCH

Post by geoff 1965 »

You could easily add that to your circuit,just an on/on switch and some component value changes
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Re: PARALLEL-CASCADE SWITCH

Post by pummpy »

If you can show me how you would do i would appreciate that . Scratching me head a bit .
Thanks .
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Re: PARALLEL-CASCADE SWITCH

Post by geoff 1965 »

add some pics of the wiring to pots & turretboard on your build,the schematic/layout you posted is one input master volume on TMB channel but the pic of your chassis is dual input TMB channel?
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Re: PARALLEL-CASCADE SWITCH

Post by JMPGuitars »

geoff 1965 wrote:
Mon 02/01/21 5:20 pm
add some pics of the wiring to pots & turretboard on your build,the schematic/layout you posted is one input master volume on TMB channel but the pic of your chassis is dual input TMB channel?
As I mentioned above, please start a new topic for this discussion since it is no longer relevant to the switch in this thread.
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