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previous: Dan Many JTM100 schems have the 16uF fi... -- 1100678719	View Thread

Re: Filtering in JTM100s

11/17/2004 4:18 PM
Wild Bill	Re: Filtering in JTM100s Off the top of my head Dan, there is no electrical difference between caps in series or by themselves. It's just like resistors - using two 100R in series gives you 200R and in parallel 50R. Electrons just don't care! However, there's another factor - MONEY! The 1st position on the filter string sees the highest B+. When you put caps in series you add up their voltage rating. Many amps have a high peak voltage on the caps when first turned on that settles down as the tubes start drawing current. If that voltage is over 450-500 volts finding a cap with the higher rating is difficult and expensive. Much cheaper to use a standard value in series to get that higher rating and besides, if you're buying in volume you get a better deal if the caps are all the same. One less box for the inventory shelf to track, too! Make sense? ---Wild Bill

11/17/2004 4:18 PM

Wild Bill

Re: Filtering in JTM100s

Off the top of my head Dan, there is no electrical difference between caps in series or by themselves. It's just like resistors - using two 100R in series gives you 200R and in parallel 50R. Electrons just don't care!

However, there's another factor - MONEY! The 1st position on the filter string sees the highest B+. When you put caps in series you add up their voltage rating. Many amps have a high peak voltage on the caps when first turned on that settles down as the tubes start drawing current. If that voltage is over 450-500 volts finding a cap with the higher rating is difficult and expensive. Much cheaper to use a standard value in series to get that higher rating and besides, if you're buying in volume you get a better deal if the caps are all the same. One less box for the inventory shelf to track, too!

Make sense?

---Wild Bill

Replies:

Dan Thats more or less what I was guess... -- 11/17/2004 5:38 PM