Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Leevi on April 26, 2017, 10:45:12 pm
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Any comments?
http://revolutiondeux.blogspot.fi/2012/05/blackstar-isf-control-whats-going-on.html (http://revolutiondeux.blogspot.fi/2012/05/blackstar-isf-control-whats-going-on.html)
/Leevi
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Ciao Risto also I noticed that Tone Control
http://el34world.com/Forum/index.php?topic=17379.msg174016#msg174016 (http://el34world.com/Forum/index.php?topic=17379.msg174016#msg174016)
at the end of the post you can see some values I've find about the components, to use this TC with a Tube amp we must adapt values
Interesting the whole Patent text on your link
Franco
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Thanks for the link Franco,
I should have checked that before starting a new topic.
/Leevi
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No, on the contrary, I think that your search for opinion was something further respect my post
where I only shared the info I found
I hope someone can add comments about that Tone Control on this thread
Ciao
Franco
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Seems pretty clever to me, but not something massively innovative, look here at the subtle differences between the fender and marshall tone stacks:
https://www.ampbooks.com/mobile/classic-circuits/bassman-tonestack-intro/ (https://www.ampbooks.com/mobile/classic-circuits/bassman-tonestack-intro/)
They are almost identical except for the resistance values in R1 and C1. I'm guessing htat they did the math for an RC circuit and made the pot in parallel on the right side so it can adjust the RC network to be more amenable there. I.e. they give you the ability to shift R1 between 33k and 56k and then the other pot adjusts the mid range on the RC filtering with an adjustment of the R instead of C. Most of what I've read about Blackstar in general though, is that it's really poorly made stuff. This is why they're so popular, anyone can afford a tube amp if its sold for pennies on the dollar and made of the cheapest possible components.
~Phil