How to build the F5

[AndrewT]

The bridges pass the same current for the same amount of time.
Witness the doubled heat dissipation compared to a single bridge. Both arrangements dissipate the same heat per bridge.

[Zen Mod]

Originally Posted by 6L6

With a dual bridge there is less stress on the transformer if (and only when) the rails sag independently from each other. With a single bridge, the transformer secondaries take the asymmetrical load, and can hum a bit.

This is not that big of a deal in a Class-A amp, and the Pass Aleph amps were made with single bridges.

Originally Posted by Zen Mod

exactly

possible DC through secondaries is a main thing , when rails are not symmetrically loaded

[Russellc]

Very interesting AndrewT and Audiosan...in the next build it would be easy (and inexpensive) to try some regular rectifiers, I could always "upgrade" later if it proves necessary.

Andrew, is there a formula or rule concerning the values of the cap/resistor
snubbers you speak of? What values for this in F-5?

Thanks in advance,

Russellc

[Russellc]

Originally Posted by 6L6

This is not that big of a deal in a Class-A amp, and the Pass Aleph amps were made with single bridges.

I have noticed that on some schematics of his, perhaps one of the alephs? I'm sure Nelson has tried it everywhich way!!!

PS: Sorry 6L6, I see you mentioned the Alephs as an example...

Russellc

[AndrewT]

Originally Posted by Russellc

............... is there a formula or rule concerning the values of the cap/resistor
snubbers you speak of? What values for this in F-5?.............

yes, is it Hagerman?
There is a lot more discussion on R+C snubbing going on in recent postings than there has been over the past few years. Worth digging into these Threads.
The important point is that the R does the damping.
The C stops the low value of the R blowing up due to excess dissipation.

[Russellc]

Originally Posted by AndrewT

yes, is it Hagerman?
There is a lot more discussion on R+C snubbing going on in recent postings than there has been over the past few years. Worth digging into these Threads.
The important point is that the R does the damping.
The C stops the low value of the R blowing up due to excess dissipation.

Oh, sorry, I thought you had tried this with an F-5 already!

Russellc

[hangguy]

I was using a couple general purpose GBPC-3510 for my F5 build. Recently, I decided to change them out and use 8 pcs of MUR3060 to make up the rectifier. This change brought some noticeable improvements over the GBPC-3510. The most apparent are the detail levels improvement and the image solidity. For the $30 I paid for the MUR3060, this is a very worthwhile upgrade for any F5 builds.

[AndrewT]

Russel,
why are you "sorry"?

[a.wayne]

Originally Posted by hangguy

I was using a couple general purpose GBPC-3510 for my F5 build. Recently, I decided to change them out and use 8 pcs of MUR3060 to make up the rectifier. This change brought some noticeable improvements over the GBPC-3510. The most apparent are the detail levels improvement and the image solidity. For the $30 I paid for the MUR3060, this is a very worthwhile upgrade for any F5 builds.

Did you do any matching ?

Originally Posted by AndrewT

Russel,

why are you "sorry"?

Sounds like sarcasm Andrew ..... !

[Russellc]

No, not at all, I thought he was saying this because he had done it this way in an F-5's power supply. That's why I inquired about the values. Apparently
this is not the case just a statement that typically he uses the snubbers. Why what are you trying to make of it?

Russellc