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Hoffman Amps Forum image Author Topic: New HoSo56 Build is Alive!  (Read 18654 times)

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Offline tubenit

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Re: New HoSo56 Build is Alive!
« Reply #50 on: April 27, 2010, 08:05:04 am »
THANKS for sharing your tweaks and successes!  That's one of many features that make this a great forum!  Glad you got it into the tone zone that you want.

With respect, Tubenit

Offline Tone Junkie

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Re: New HoSo56 Build is Alive!
« Reply #51 on: June 14, 2020, 02:01:00 am »

So have we come to a consensus on what cap and resistor is for the 2 el84 tubes On the HOSO56. This one looks like 250UF and 130R and another one I have shows 100R and 100 UF, another 100R and 8UF.
Any thoughts . Im at that point on the board.
Thanks Bill

Offline sluckey

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Re: New HoSo56 Build is Alive!
« Reply #52 on: June 14, 2020, 05:49:04 am »
100Ω to 150Ω is very common for any cathode biased 2xEL84. 50µF to 500µF is common for the bypass cap.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline tubenit

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Re: New HoSo56 Build is Alive!
« Reply #53 on: June 14, 2020, 06:51:54 am »
Your voltages will determine the cathode resistor needed.  I'd try either 130ohm or 150ohm as a starting place. IF your EL84 plates have 350v or less on them & you like the tone, then I'd leave it.

Tonewise, the smaller 8uf value gives a smoother sound when the amp is really cranked into overdrive. At lower volumes and not cranked into overdrive, you may think the 8uf is too thin?   

A larger value like 100uf will give tighter bass and perhaps more "crunch" (instead of smoothness) in the overdrive.  Aiming for a cleaner tone for jazz,  I chose 50uf with the 6BM8 tubes in my current HoSo56 "the minimalist".

This is a "season to taste" stage of the amp. 

With respect, Tubenit

Offline Tone Junkie

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Re: New HoSo56 Build is Alive!
« Reply #54 on: June 14, 2020, 04:51:38 pm »

Thanks guys I do like a hotter bias . So will start with 100R.  351V was my last B+ when I used this transformer .  Last night I finished a cathode cap Box going from 8Uf to 250UF So I can dial it in. One of the last cap or resistor boxes I didn't have.
May your day be blessed.
Bill

 


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