The warning is valid.
If I could misunderstand his post then maybe others could do that as well.
Obviously Koldby read it differently from me.
The pic in post2057 shows dual primaries connected in parallel.
That pic does not show TWO transformers. It shows dual primaries and dual secondaries.
But that pic was posted after my warning post.
If I could misunderstand his post then maybe others could do that as well.
Obviously Koldby read it differently from me.
The pic in post2057 shows dual primaries connected in parallel.
That pic does not show TWO transformers. It shows dual primaries and dual secondaries.
But that pic was posted after my warning post.
AndrewT,
I believe you misunderstand him.
He has TWO transformers , each with a 220V primary and wants to parrallel couple these two transformers and then series couple the secondaries from the two transformers.
As long as the phases is the same for the two secondaries , this is ok as far as I can see..
Koldby
Thank you for your intervent.
Now I could rest assure to proceed my `Goldmund`.
I have just got the NOS BSS7/BSS74 with the help of a friend from China.
Hopefully that the project might come to completion before this Christmas.
I am sorry for the iinconvenient caused as English is not my mother tongue.
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obviously you have no experience in paralleling transformers that is why your comment....
It was not relevant to the proposal discussed in this thread. The primaries were clearly stated to be 220V.. You know the rules about commenting on moderation decisions. End of discussion on the removal of your post.That's probably because the rails are not symmetrical. For example +25V and -10V.
Check for example the Matti Otala's low TIM amplifier, that is also used by Electrocompaniet.
Hi Luke ,
I have, for free two PCB's from a friend ,and 6 laterals N and P (I bought 10 pairs of EXICON's)left from my last project , so I have built the second amplifier with better parts . I like the sound , warm close to tube amplifier . I have also built 2 Grommes A260 modified PP amplifier with russian 6P3C and GU 50 tubes . Ultimately the sound depends on the speakers
@nikosokey
thanks for your comments , I will mount a bigger heatsink on VAS transistors.
Yes, you right , they are hot ......
regards Alex.
Hi.
I just have to ask.
I see a lot of You have gone for those EXICON output transistors.
But wich ones are the superior here? SK175/SK50 og the EXICON's?
I am a late starter in this project, but have built quite a few amps, but for some reason never with any of theese transistors. (The SK175/SK50 are original TANDBERG-transistors I have in stock here)
I also have a preamp design I probably should share with You.
I do not know it's origin, but have used it for some years, nad I'm very happy with how it sounds.
And Alex, I can't get to the dropbox-pics You put out a link to in here.
Could you also provide me with Your complete BOM and tweaks You have made to your fabolous builds?
Looking forward to start this.
Just a bit of funfact:
Tandberg introduced the term DIM, wich in fact is excactly the same as TIM already in 1974.
Also I was lucky enough to have an professor as my teacher when I got my education as an electronics engineer. The very same professor wich trained people behind DOXA, SONOTRON (Later ADYTON), and other HIEND-manufacturers in Norway.
We named him "Professor Balthasar", as he looked just like him.
Tandberg introduced the term DIM, wich in fact is excactly the same as TIM already in 1974.
Also I was lucky enough to have an professor as my teacher when I got my education as an electronics engineer. The very same professor wich trained people behind DOXA, SONOTRON (Later ADYTON), and other HIEND-manufacturers in Norway.
We named him "Professor Balthasar", as he looked just like him.
Hi Jay.
Any diagrams for the powersupply?
It is mentioned in the article following the schematics for this amp,
"The amplifier is fed by symmetrical voltage 19V -44V and +/-26V to the power stage".
I am confused of the use of the term symmetrical voltage of 19V and -44V.
Clearly non-symmetrical as I can see it.
Anyone who can give some good input on this issue?
Hi, I don't have the power supply, sorry.
The original article in the Greek site I think was not accurate (τροφοδοτείται με συμμετρικές τάσεις +19V και -44V). The English translation found in the PDF is more accurate "The amplifier is fed by non symmetrical voltage 19V -44V and +/-26V to the power stage"
Here is the English translation (PDF)
http://sportsbil.com/other/ELECTROCOMPANIENT SCH.pdf
Here is in Greek
Electrocompaniet
The original Electrocompaniet 25 watt class A amp
The supply voltages are not correct the feeds are symemetrical +/-27V for the input stage and +/- 33.8V for the output stage.
The supply voltages are not correct the feeds are symemetrical +/-27V for the input stage and +/- 33.8V for the output stage.
