Cascade mod on 1974x clone

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Plig88
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Cascade mod on 1974x clone

Post by Plig88 »

Hello .. I open this issue not because I have a problem with the amp. I just want to increase the gain. I just changed the v1 tube of normal section from ecc83 to ecc83s and it has a big difference in gain… but I need to make the cascade mod with parallel switch .. I found this schematic for cascade but it’s little different from the original 1974x schematic . The one is the cascade and the other is the normal channel v1 section .. can I found what parts remove first from my 1974x?
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JMPGuitars
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Re: Cascade mod on 1974x clone

Post by JMPGuitars »

Hi,

The photos you posted have all the information you need. The original 18W is 1974, the Reissue is 1974X. In either case, look at the drawings you posted, including the higher quality original of the cascade mod: files/Zaphod_Phils_18W_Cascade_Mod.pdf

The cascade mod, where it says "to phase inverter" - that's what connects to the .01uF C4 on your schematic. Everything before that in that section can be changed to match the mod, or you can keep your tone knob and tweak it.

Thanks,
Josh
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Bieworm
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Re: Cascade mod on 1974x clone

Post by Bieworm »

On my classic I ended up cascading the tremolo channel into the normal channel. There was a bonus that way for having a 2nd tone control. Worked great!!!
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zaphod_phil
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Re: Cascade mod on 1974x clone

Post by zaphod_phil »

I love the direct simplicity of that cascade mod!
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Bieworm
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Re: Cascade mod on 1974x clone

Post by Bieworm »

zaphod_phil wrote:
Tue 09/07/21 7:07 pm
I love the direct simplicity of that cascade mod!
Thanks to your drawing it was pretty easy.. and fun to read😀
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