Redplating

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JazzGuitarGimp
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Re: Redplating

Post by JazzGuitarGimp »

Smokebreak wrote:I take that back about the Larmar. Turns out the sovtek I put in V1 that squelched oscillation just sounds awful, and hums. I will now shutup and tube swap. :oops:
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Roe
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Re: Redplating

Post by Roe »

Smokebreak wrote:Very interesting. It was actually V5 that did it but I'll keep that in mind as I'm not quite finished with this one yet... after rehearsing with this amp last night, I am NOT a big fan of the larmar in this amp. Clean tones are ok, shred tones are good, but everything inbetween just sounds kinda lifeless. The whole Marshall mojo just gets lost with the master dialed back. I do like the cascade mod though.
increasing NFB helps with this. I prefer a variable NFB (resistor + pot) when using the larmar
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Smokebreak
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Re: Redplating

Post by Smokebreak »

Where do you like your sweep? 47k with 50k pot?
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Roe
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Re: Redplating

Post by Roe »

Smokebreak wrote:Where do you like your sweep? 47k with 50k pot?
usually 22k with 220k pot into 16 ohms secondary
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Reeltarded
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Re: Redplating

Post by Reeltarded »

Smaller and larger. 27k+250k on 16.. ooooh not quick enough!

BUT.. On an amp that has NFB I do not like the PPIMV at all. It makes a big amp sound like a raging buzz saw. AM vs FM. Efff Emmmm.. no static at all..

Cathode master plus simple master is the best yet for me. Still thumpy at television volume.
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Smokebreak
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Re: Redplating

Post by Smokebreak »

Reeltarded wrote:

Cathode master plus simple master is the best yet for me. Still thumpy at television volume.
I back to thinking like this as well, at least for this amp. I'll play with the NFB too. I've moved to Chupa territory and am really diggin it, and am about to do the cathode master. But now, I'm getting DC on the guitar pots. I've read through the current thread, and though I'm using fiberboard, I on't think it's a moisture issue, as it just starting happening today when I went with all .68/820. It started yesterday actually, when I replaced an electrolytic cathode cap on V1 with a poly. I switched it back to electro and that fixed it, but now, with stock chupa values(all electro), I get DC. There is a cap at the input on chupa scheme(which is obviously there for a reason), but all I really did was change cathode values and switched coupling caps on V1. Any hints here?
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Reeltarded
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Re: Redplating

Post by Reeltarded »

Yep! Use that big cap on the input. It will block DC that is sneaking up from the grid on V1. What is your plate on that stage? Is that the nutty 470k thing?
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Smokebreak
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Re: Redplating

Post by Smokebreak »

I went with 330K but it's still pretty ridiculous. I may have to put in the "pussy trimmer"
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