vta 70 can capacitor

kost: Posts: 22
Join date: 2009-05-12
Age: 48
Location: athens

Post n°1

vta 70 can capacitor

by kost on Wed Mar 31, 2010 12:04 pm

Hi
There are two can capacitors available from dynakitparts
Both are 80,40,30,20, one is 525 volts and the other is 550-600 volts.
Which one is beter for the vta 70?

regards
kost

wolverine

wolverine: Posts: 59
Join date: 2010-02-20

Post n°2

Re: vta 70 can capacitor

by wolverine on Wed Mar 31, 2010 12:14 pm

Kevin at Dynakit is great at helping with questions, he would be happy to guide you I am certain.

I think the general consensus I have seen here is that the Dynaco tends to have a large rush up in volts at turn on, so likely most would say that having the higher rated cap would be a nice extra measure of protection. The capacitance of the cap is still the same either way, the higher rated one just gives more protection against current rush when the amp is initially turned on.

wolverine

Bob Latino

Bob Latino: Admin; Posts: 1197
Join date: 2008-11-26
Location: Massachusetts

Post n°3

Re: vta 70 can capacitor

by Bob Latino on Wed Mar 31, 2010 1:32 pm

kost wrote:Hi
There are two can capacitors available from dynakitparts
Both are 80,40,30,20, one is 525 volts and the other is 550-600 volts.
Which one is beter for the vta 70?

regards
kost

Hi Kost,

Right now the CE 525 volt is out of production at CE down in Arizona. I think they are changing over their production line or moving it to a new location - SO - the Dynakitparts 550 volt cap is really the only 80, 40, 30, 20 quad cap available right now. It is a little more costly but IMHO it is a more durable cap than the CE cap because it has a higher voltage rating.

When you install one into an ST-70 just have the "80" section face the back of the amp and all the other sections will be in the proper orientation.

Bob

janka

janka: Posts: 2
Join date: 2010-06-25

Post n°4

Re: vta 70 can capacitor

by janka on Mon Jul 12, 2010 12:28 pm

I'm going to order a 550vdc cap for my st-70. However, I've been warned going above 50uf on the first section can put my 5AR4 at risk. What is the benefit of the 80/40/30/20 @ 550vdc versus the 30/20/20/20 @550vdc ? Does the 80uf in the first section really pose a risk to the 5ar4?

Thanks!

Bob Latino

Bob Latino: Admin; Posts: 1197
Join date: 2008-11-26
Location: Massachusetts

Post n°5

Re: vta 70 can capacitor

by Bob Latino on Mon Jul 12, 2010 12:38 pm

janka wrote:I'm going to order a 550vdc cap for my st-70. However, I've been warned going above 50uf on the first section can put my 5AR4 at risk. What is the benefit of the 80/40/30/20 @ 550vdc versus the 30/20/20/20 @550vdc ? Does the 80uf in the first section really pose a risk to the 5ar4?

Thanks!

Hi Janka,

When installed properly (the cap is oriented and installed so that the 80 section faces the rear of the amp), this cap will be set up so that the 40 section is the first section that connects to the 5AR4. A choke then connects the 40 section to the 80 section. The 80 section is connected AFTER THE CHOKE. This is the proper way to connect the 80, 40, 30, 20 cap to an ST-70.

Bob