2 trannies on one powersuply

Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
Assuming that you are looking for about +55 Volts, the
most ideal way would be to give each 40 V secondary
its own bridge, with its leads driving the "AC" pins on
the bridge, and paralleling all the + bridge pins and -
bridge pins to form one supply. The primaries would
all run in parallel.

If all the secondaries were matched, you certainly could
simply parallel them all into one bridge and save yourself
the cost of 3 bridges.

:cool:
 
2 trannies

Per,

I was surprised to pick up this post. I guess the *fight* you refer to possibly is the exchange between mrfeedback and myself in the other thread? Well, it was a heated exchange perhaps, but I think we both gracefully defused it, I didn't consider it a fight.

Rather than repeat myself again, let me offer some advice, which you take or leave as you please.

You are frustrated because nowbody gives you The Trvth (tm). You have understood by now that this does not exist. Look at the discussions on opamps. 100 people, 101 opinions.

Your thread has a lot of info, reasoning, experiences etc. You disregard all that by just coming back with the same question.

I had exactly the same experiences starting to be interested in electronics.

You want to advance, and *understand* why one solution works better for you than another? Print out the previous thread, take an afternoon off, go through all the arguments. First weed out the ones that state opinion rather than reasoned convictions, because opinions don't help you here.
Then go over the arguments, try to follow the poster and decide if you can agree or not. Throw away the most unlikely, and eventually you get to a solution YOU BELIEVE IN, you can defend against others and you will never have the same problem again. That's a promise.

Unfortunately, because with this medium you can instantly pose your question to the experts, you expect instant return of The Trvth (tm). If it were only that simple, we would all be Nelson Pass's ;)

Keep us posted


Jan Didden
 
In my defense

Allow me the opportunity to defend myself... :D

Firstly, the amount i know about transformers can be written in 5 inch letters on the head of a pin.

I duly note all you have just said - yes, i have disregarded all that was suggested in my original thread. You see, i am a student. I have very little money. I obviously try whenever possible to save a couple of bucks if possible. Now along comes a dream offer of 2 x 225VA toroids for US$38, whereas a new 500VA will set me back US$80. Now i haven't a ******* clue how i could use these two for one amp. So i post the topic, and get many different viewpoints. I am a very cautious guy - i just don't want things to blow up in my face, so i'm not going to just connect things up willy-nilly, turn on and hope i'll see my grandchildren one day. No ways. I want 100% assurance that something i try is gonna work before i do it. Plus, i don't want to smoke 2 perfectly capable trannies because of someone's mistaken opinion on the subject of transformers.

Yes, it is easy to just ask the experts, and I would like to thank Mr Pass for his reply. I just want a straight, correct answer that will work for my situation from someone who has done this before - not some opinion that due to longterm misconception has rooted itself as fact in a persons mind. The point i'm trying to make is that if one knows something is 100% true because the theory makes sense and they've tried it and it works, then go ahead an spread that knowledge to those who will greatly benefit from it. But if one is just too eager to get ones name on the post and look intelligent infront of your mates, then one should shut ones trap and perhaps try and learn from others who know more than you do. I am not trying to insult anyone here, just trying to point out a problem that occurs frequently in posts.

So i submit to you the question still. To put this topic to rest once and for all, and for the sake of my and your sanity, and to save trees,harddrive space and the lesser spotted south african polkadot tree gorilla:

How do you connect two dual 40V toroids (centre tapped) to a single amplifier with +56 and -56 rails without:

(a) wasting power due to parralelling unequal secondaries
(b) not using the full 225VA per tranny
(c) causing lengthy defense posts and endangering the lesser spotted south african polkadot tree gorilla

A diagram would be ideal. I promise this is the last time i'll ask :)
 
2 trannies etc

djnigma,

I get really tired now. You don't get my point. The only one that can decide the "right' answer is you. If you only trust one person, email him privately for his advice. If you ask this forum, you get a zillion answers. If you don't have enough knowledge to judge which one to run with, nobody can help you, except yourself. There's no way around educating yourself. You should know, you're the student.

And one more thing. Specifically thanking just one person is very, very unfair to all the others that put in at least the same or more effort to help you again and again.

Jan Didden
 
Re: 2 trannies etc

janneman said:
djnigma,

I get really tired now. You don't get my point. The only one that can decide the "right' answer is you. If you only trust one person, email him privately for his advice. If you ask this forum, you get a zillion answers. If you don't have enough knowledge to judge which one to run with, nobody can help you, except yourself. There's no way around educating yourself. You should know, you're the student.

And one more thing. Specifically thanking just one person is very, very unfair to all the others that put in at least the same or more effort to help you again and again.

Jan Didden

You are right. I didn't really see it that way - i am sorry for being an idiot. Thankyou to everyone for your help and suggestions.
 
2 trannies etc

You learn. I learn. Idiots don't.

One of my hero's is Richard Feynman, famous physisist and Nobel Laureate. He said:

“The same thrill, the same awe and mystery, come again and again when we look at any problem deep enough. With more knowledge comes deeper, more wonderful mystery, lurking one on to penetrate deeper still”

Richard P Feynman, The pleasure of finding things out, Helix Books/Perseus Books, 1999, pg 144.

I am still scratching the surface, but enjoying it greatly.


Jan Didden
 
Per said:
As usual when posting a simple question, there is (on this site) almost never a simple answer. I greet and thank Mr. Pass. It is nice to get advice from such notabilities....
I expect, if needed, that I will buy a partner to my present tranny, and plug it in with the first one.

;) Per.

Well done! Of course, it isn't necessary to confirm the contributions of Peter, Eric, Andy, Bill, JasonL, HH, Dice45, Grollins and yes, myself, plus the many others that I forget but that freely give from their time and knowledge to try to help people like you to make sense of audio electronics. Your post is a fine model of thoughtlessness.

I'm done here.

Jan Didden
 

Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
I second that motion. When I began entertaining myself
by contributing to this forum, I was perfectly aware that
playing the elephant on the dance floor could upset the
delicate balance that makes this such an wonderful forum.

So don't blame me for everything and don't give me all the
credit.

(translation: don't blame me for anything)

:Pumpkin:
 
2 trannies

Just to avoid any wrong impression:

I have great respect for Nelson and his vast audio knowledge. I even more admire his uncanny marketing savvy. After all, he is the only manufacturer that managed to get a thread under his company name.

He is in a very delicate position, as he himself is well aware. But he shows considerable restraint and thoughtfullness and this community could use a few others like him.

But I have a problem if 10 or 20 people contribute to a thread and a single one is thanked, whoever it is. I make a point of thanking a contributor who gave me a particular good piece of info. It makes two people happy, and from where I come this is considered common decency.

If that is not your way, fine with me. But the least we can do is be fair to each other.

I wish you all the best in your endeavours.

Jan Didden
 
Hi Jan.

I thanked everybody in advance, none mentioned none forgotten. I never expected to hear from Mr. pass, thats why I thanked him personally. I was looking for a simple answer but I should have expected that this simple thread would turn in to a philosophic debate on something, that basicly had nothing to do with what I asked in the first place. As you, I can also get a little tired when people write lines and lines about how this and that, but (almost) not contributing to whatever question started the thread. Maybe i'm naive but when I post a question, I kind of expect that most of what people write back, will actually have something to do with that specific question. If you read on in this thread, you'll see that most of it, dos'nt concearn to trannies on....
I was not trying to insult anybody, I think it is a little comic that people will take the time to and effort to write to me, about how thougtless I am. I (now) thank everybody contributing to the thread.

Kindly Per.