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Hoffman Amps Forum image Author Topic: Output P/T suggestion  (Read 2394 times)

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Offline ernie_jr

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Output P/T suggestion
« on: March 29, 2015, 08:16:41 am »
Building a bass amp, based off SUNN but will be in pentode mode. 560 volts on plates, Which would be a better o/p tranny Hammond 1650R (100watt, 5000 ohm) of 1650n (60watt, 4300 ohm).
thanks,
Ernie

Offline Willabe

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Re: Output P/T suggestion
« Reply #1 on: March 29, 2015, 09:06:41 am »
What power tubes and how many?


            Brad     :icon_biggrin:

Offline ernie_jr

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Re: Output P/T suggestion
« Reply #2 on: March 29, 2015, 09:26:11 am »
2x KT 88,
thanks

Offline shooter

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Re: Output P/T suggestion
« Reply #3 on: March 29, 2015, 11:32:50 am »
The data sheet I have shows 4-5k at 560vdc.  I'm working out kinks in a Kt88/6550/EL34 with 430v plate and I'm using a 4K OT.  I would think the higher wattage would heat up less, or not saturate as soon, which I believe keeps thing "tighter" sounding?
Went Class C for efficiency

Offline clyde

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Re: Output P/T suggestion
« Reply #4 on: March 29, 2015, 02:20:47 pm »
I've used the 1650R at 600+ plate volts with success.  The amp in question gigs continuously and has for 9 years. 


 


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