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Hoffman Amps Forum image Author Topic: KT88 PP amp  (Read 33504 times)

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Offline Ritchie200

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Re: KT88 PP amp
« Reply #100 on: April 15, 2019, 06:06:06 pm »
For what it's worth, I really like the Presence on my Major.  Depending on what guitar I use, it allows me to dial in a little bite.  Typically turned off with a strat, it can give a little more top end if loaded down with a pedal(s) on the front end.  With a humbucker it allows for a little or a lot of shimmer over the top - similar to a live Jimmy Page.  As we all know, the Presence is different than just turning up the treble.  It sure makes my amp a lot more flexible.

Jim

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Offline uki

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Re: KT88 PP amp
« Reply #101 on: April 15, 2019, 06:46:50 pm »
For what it's worth, I really like the Presence on my Major.  Depending on what guitar I use, it allows me to dial in a little bite.  Typically turned off with a strat, it can give a little more top end if loaded down with a pedal(s) on the front end.  With a humbucker it allows for a little or a lot of shimmer over the top - similar to a live Jimmy Page.  As we all know, the Presence is different than just turning up the treble.  It sure makes my amp a lot more flexible.

Jim

The plan is to have a presence control and the control for the feedback loop as well.

Also there are few more ideas cooking at the moment, I'm reading, researching, gathering info !

Check out also this topic. Body control is another candidate for the amp!
Theory is when everyone knows everything but nothing works, practice is when stuff works but nobody knows why !!!
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Offline uki

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Re: KT88 PP amp
« Reply #102 on: April 22, 2019, 11:26:37 pm »
Some update on this project:

Bias balance, CUT control and

Negative Feedback control, what value for the pot should be used, keep the resistor with smaller value ?

Theory is when everyone knows everything but nothing works, practice is when stuff works but nobody knows why !!!
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Offline tubenit

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Re: KT88 PP amp
« Reply #103 on: April 23, 2019, 05:16:41 am »
Thanks for sharing the schematic!  I'll be very interested in hearing how you like this amp once built.

With respect, Tubenit

Offline PRR

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Re: KT88 PP amp
« Reply #104 on: April 23, 2019, 02:41:34 pm »
> Negative Feedback control, what value for the pot should be used,

This depends on the speaker and your style. NOT an "electronic" question. Put in two alligator clips and try values from half of stock to infinity.

 


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