Cap Voltage..?

[Homebelly]

I just read through this thread hoping it might answer a question i have.
https://tubeamparchive.com/viewtopic.ph ... c&start=45

Right now i am assembling parts for a JTM45 build, and also writing a BOM for a 183/Bluesmaster hybrid build, and i am wondering why the Dumble amps use 600V caps while the marshall amps use 400V.

What would be the differences if you were to swap these out, maybe build marshall with 600V caps, or a dumble with 400V caps..?

[ToneMerc]

Most of the axial "mustards" that I've seen are either in 400 or 1000V ratings and the 600V ones are the much smaller radial types. Keep in mind that in most circuit locations you will never exceed the 400V rating. I would imagine that Marshall simply choose the most practical for the application, the 400V rating and the fact that sourcing parts from Europe was cheaper than importing caps from the US.

TM

[Homebelly]

would there be a running or tonal difference using 400V over 600V?

In other words, would the amp sound different, or would there be a chance that it would turn into a fireworks display if you replaced all of the 600V with 400V?

Also, if you decided to build using 400V cap's, would you need to alter any other components..?

The reason i'm asking is because i have it in my head to build a marshall flavored dumble.

So, i'm thinking that as a starting point i can swap out all of the 600V 2PS OD's and replace them with Sozo's and then go with the basic bluesmaster topography then look at other changes as i go along.

However, something tells me it isn't as simple as that..

[ToneMerc]

would there be a running or tonal difference using 400V over 600V?

In other words, would the amp sound different, or would there be a chance that it would turn into a fireworks display if you replaced all of the 600V with 400V?

Also, if you decided to build using 400V cap's, would you need to alter any other components..?

The reason i'm asking is because i have it in my head to build a marshall flavored dumble.

So, i'm thinking that as a starting point i can swap out all of the 600V 2PS OD's and replace them with Sozo's and then go with the basic bluesmaster topography then look at other changes as i go along.

However, something tells me it isn't as simple as that..

Well, you have to talk apples to apples here....

would there be a running or tonal difference using 400V over 600V?

In the context of let's say an orange drop, the tangible difference between a 4PS verses a 6PS most likely isn't noticable. Although, the 16PS(1600V) is different in construction from a 6PS.

However, if you are talking about tonality in the context a 400V "mustard" or Sozo verses a 600V PS series "orange drop" that's a different comparison.

The reason i'm asking is because i have it in my head to build a marshall flavored dumble.

I think you are chasing the wrong tail if you think swapping out caps will Marshall like a Dumble. You might find out that you may have only smoothed things out a bit.

Look at it this way...

A JTM45 with 460V on the plates, an 8.8K radiospares OT and true KT66's does not sound exactly like a JTM50 with a 3.4K Drake OT and EL34's with 420V on plates, even if both are using a GZ34 rectifer. Now neither one sounds exactly like a JTM45/100 either, but what do they have in common, the exact or almost the same circuit topology and coupler values....see my point.

If you want to inject some Marshall flavor in a Dumble, I would start with the PI section first, aka the Bluesmaster PI.


TM

[Homebelly]

So, i'm thinking that as a starting point i can swap out all of the 600V 2PS OD's and replace them with Sozo's and then go with the basic bluesmaster topography then look at other changes as i go along.

However, something tells me it isn't as simple as that..

Oops ...
That should have been 6PS..
Put that down to an "operating a computer while rocking baby to sleep" error.

Cheers for the pointers..

[Structo]

This information is aimed at some of the newer members or people that haven't dabbled in electronics for years.

I see a lot of people talk about "orange drops" as if there is only one kind.
The orange kind, well I suppose that is true.

But there are different dielectrics used among the orange drop family.
Mainly polyester and polypropylene.

If you go to the SBE site there is a chart that shows all the different kinds of drops they make.
Some are round, some are pressed.
Film foil, metalized film, etc.

6PS, 715P, etc.
There is something like 42 different orange drop caps!

http://orangedrop.sbelectronics.com/product_specs.html

The kind we use and talk about in the Dumble section are the 6PS caps.
The PS caps can be either polyester or polypropylene.

The polyester caps are rated from 200v to 1000v.
The polypropylene are rated from 1600v to 2000v.

The 6PS caps we use are rated at 600v.