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Hoffman Amps Forum image Author Topic: 2204 treble peaking caps  (Read 2523 times)

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Offline jcm-jmp

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2204 treble peaking caps
« on: February 14, 2021, 07:38:27 am »
hey guys just built a 2204. I completely removed the 1st treble peaking network. Cap and resistor completely bypassed. I like what it does for tone and gain. What are you guys thoughts on this. Is it going to create issues elsewhere in the preamp?
DAZED AND CONFUSED!

Offline sluckey

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Re: 2204 treble peaking caps
« Reply #1 on: February 14, 2021, 07:48:24 am »
It's all good.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline thetragichero

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Re: 2204 treble peaking caps
« Reply #2 on: February 14, 2021, 10:19:15 am »
someone on the marshall forum suggested 2n2 for the first treble peaker cap and i like it. bypasses the resistor for frequencies above ~150hz

Offline PharmRock

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Re: 2204 treble peaking caps
« Reply #3 on: February 14, 2021, 01:46:03 pm »
This is good info...I am in the process of building a "hybrid" 1987/2204 switchable amp that is basically a simple man's version of Sluckey's Dual 50.  I've read up on the forums and this seems like a very popular place to mod the amp if its overly bright. 

someone on the marshall forum suggested 2n2 for the first treble peaker cap and i like it. bypasses the resistor for frequencies above ~150hz
Would this replace the 470pf cap that runs in parallel with the 470K resistor? 

hey guys just built a 2204. I completely removed the 1st treble peaking network. Cap and resistor completely bypassed. I like what it does for tone and gain. What are you guys thoughts on this. Is it going to create issues elsewhere in the preamp?
So in this case, is the 1000pf cap across the preamp volume pot still in place? 

Offline thetragichero

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Re: 2204 treble peaking caps
« Reply #4 on: February 14, 2021, 02:20:22 pm »

Would this replace the 470pf cap that runs in parallel with the 470K resistor? 


yup. should work a lot nicer with high gain instead of removing both the R and C because too much gain on the lower frequencies gets muddy and mushy (this is why the slo uses 1uf cathode bypass caps). changing the 470pf to 2n2 lowers the corner frequency from 720hz to 154hz

 


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