Presence=more attack?

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Steven_nl
Posts: 95
Joined: Mon Apr 14, 2008 7:48 am

Re: Presence=more attack?

Post by Steven_nl »

llemtt wrote:It seems that you don't have enough damping on your speaker, try a 3k9 feedback resistor instead of a 4k7, IMO that's the correct value for a 50w.

(moving the feedback tap from 4 to 8 ohm as suggested as the same effect)

cheers
teo
Is this an error in "my" amp?
bluesfendermanblues
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Re: Presence=more attack?

Post by bluesfendermanblues »

No....on most schematics (also Ceriatone's) the feecback circuit for a 50W is 4.7K/390 connected to the 4 ohm tab.

However, if you like a looser sound connect it to the 8 ohm tab instead. Just an idea.
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dogears
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Re: Presence=more attack?

Post by dogears »

Connecting the NFB to the 8 ohm tap increases the voltage being fed back. This increases the NFB. In my experience, this is not looser at all. It is tighter. More feedback. Less NFB is looser and more raw for me..... Anyone else agree?
bluesfendermanblues wrote:No....on most schematics (also Ceriatone's) the feecback circuit for a 50W is 4.7K/390 connected to the 4 ohm tab.

However, if you like a looser sound connect it to the 8 ohm tab instead. Just an idea.
mlp-mx6
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Re: Presence=more attack?

Post by mlp-mx6 »

I agree. Less is looser.
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erwin_ve
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Re: Presence=more attack?

Post by erwin_ve »

dogears wrote:Connecting the NFB to the 8 ohm tap increases the voltage being fed back. This increases the NFB. In my experience, this is not looser at all. It is tighter. More feedback. Less NFB is looser and more raw for me..... Anyone else agree?
bluesfendermanblues wrote:No....on most schematics (also Ceriatone's) the feecback circuit for a 50W is 4.7K/390 connected to the 4 ohm tab.

However, if you like a looser sound connect it to the 8 ohm tab instead. Just an idea.
Agreed! :D
BobW
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Re: Presence=more attack?

Post by BobW »

dogears wrote:Connecting the NFB to the 8 ohm tap increases the voltage being fed back. This increases the NFB. In my experience, this is not looser at all. It is tighter. More feedback. Less NFB is looser and more raw for me..... Anyone else agree?
bluesfendermanblues wrote:No....on most schematics (also Ceriatone's) the feecback circuit for a 50W is 4.7K/390 connected to the 4 ohm tab.

However, if you like a looser sound connect it to the 8 ohm tab instead. Just an idea.
I concur.
talbany
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Re: Presence=more attack?

Post by talbany »

Hi
Hard to discribe and I'm not quite sure I sully understand your remarks. Are you suggesting raising the Presence/NFB softens the damping factor of the speaker? I would expect raising the Presence lessens damping? Maybe I'm misinterperting "damping" (did a quick search on wiki, more complicated then I thought.)
Anyway, I think I am refering to the percussiveness of the attack.
I prefer the Presence to be set to about 3 or 4 for a softer atack. But then my amp is to dark. When set at 8 it sounds nice and open without being harsh, but when you hit a string it has that percussive pop.
Steven

Yeah it's confusing to explain since when you begin to turn the pot up you decrease the amount of NFB so it kind of works opposite to the phrase...Turn up the pot less FBK..I am not sure if changing the tap is going to buy you much if you like a certain amount of NFB cause you like the softer/tighter whatever attack feel but miss the sparkle then the bright caps and some of Scott's changes may help.. For me I like the hi end pad the presence gives me in OD but not so much for clean so you may want to look a channel deeper.... I like you also like the presence set fairly low for the softer vibe since I have a heavy hand.. I install another relay engages a bright cap when the clean channel is on and takes it out when you go to OD.. You can put a switch on the front that engages it all the time or leaves it off.. Somewhere I have a layout on it here... Hey Just another suggestion if you want to sparkle up the clean channel ..Also Bob I's suggestion of a smaller presence cap may be worth a try.. Also make sure your amp has the 500pf bypass cap on V1b.. Good Luck!!

Tony
" The psychics on my bench is the same as Dumble'"
Steven_nl
Posts: 95
Joined: Mon Apr 14, 2008 7:48 am

Re: Presence=more attack?

Post by Steven_nl »

Guys thanks a lot for your input! I rea;y appreciate it.
Steven
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