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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
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Old 10th April 2021, 03:37 AM   #81
RafaPolit is offline RafaPolit  Ecuador
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Would I be correct in assuming that the two front ends that don't use the transformer are the ones that are most likely to have a different "sound signature" than the included front ends with the Kits?

(I know the simplest answer is: "build them all and try for yourself", but if someone was to just talk about things and theorize about possible scenarios, please humor me! )

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Old 10th April 2021, 03:42 AM   #82
hifiZen is offline hifiZen  Canada
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
GREAT namesakes, Mark!

I've spent quite a few "pandemic hours" on Drachinifel's youtube channel. Naval history fascinates me, even though I'm more aviation aficionado than nautical nerd.

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Old 10th April 2021, 03:51 AM   #83
hifiZen is offline hifiZen  Canada
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Rafa,

The transformer will certainly impose it's sonic thumbprint on the sound signature, though they can be extremely transparent sounding (I used Cinemag iron at both input and output of my current preamp, and their sonic imprint is quite subtle). The circuit driving the transformer primary winding will have a large effect on how transparent the transformer is, both in terms of distortion and frequency response.

So there's plenty of room to play with the sound signature either with or without the transformer, but I surmise the the front ends will have progressively less transformer coloration as you go from the kit front end, to Scourge, to Bulwark (in that order) ... just based on my guesses about their respective output impedances into the transformer primary.
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Old 10th April 2021, 04:01 AM   #84
6L6 is offline 6L6  United States
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Build them all and tell us what you think.


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Old 10th April 2021, 04:04 AM   #85
6L6 is offline 6L6  United States
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Drach is fantastic. Particularly when he’s talking about something specific, not just talking about guns and armor on a big boat.

Example - The Salvage of Pearl Harbor Pt 1 - The Smoke Clears - YouTube
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Old 10th April 2021, 06:18 PM   #86
Mark Johnson is offline Mark Johnson  United States
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
So far I'm liking the Relentless front end card (post #19) a lot. It's the first one with all-SMD components and the number of parts is small, so its signal path is reasonably minimal. However Relentless does use an Edcor transformer, so it's hard to know whether the sonic signature is dominated by the circuitry or by the transformer.

I like the other cards too, don't get me wrong, but Relentless is mighty nice and deserves to be mentioned occasionally.
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Old 10th April 2021, 06:27 PM   #87
TungstenAudio is offline TungstenAudio  United States
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I'm sure if you chose to share the Relentless front end, that some of us would come to appreciate it as much as you do.
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Old 10th April 2021, 08:46 PM   #88
codyt is offline codyt  United States
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Quote:
Originally Posted by TungstenAudio View Post
I'm sure if you chose to share the Relentless front end, that some of us would come to appreciate it as much as you do.
+1
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Old 11th April 2021, 04:16 PM   #89
tubesguy is offline tubesguy  United States
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+1 as well. Unless I'm missing something (something like the other side of the board), the Relentless appears to have only has one active device, correct?
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Old 11th April 2021, 04:58 PM   #90
Mark Johnson is offline Mark Johnson  United States
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Scourge, Bulwark, Marauder, Dreadnought "front end" cards for DIY VFET amp
Nothing mounted on bottom side of Relentless PCB. Some of the vias between TopCopper and BottomCopper are visible in the photo below, for example in a horizontal row about 1/8th of the way down from the top edge of the board. As you know if you've ever laid out or soldered an SMD board, they always have quite a few vias.

A few key words in the Principles Of Operation silkscreen text have been deleted, but there are no components or PCB footprints hiding beneath the blue boxes. Truthfully.

Most of Relentless is undisclosed.



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