Yes your statement might also be true too.But you know that it is not a good think to use capacitor at the end point for life factors etc.And the distortion of capacitor increases by this way.
But you are using a very high quality sounded F5 Class A amplifier.This is a push pull class A amplifier.
So why not give some more ten bucks and use higher capacitance?When i add more capacitor i can easily see that bass and treble performance improves.
Some diyers/buyers give hundreds and thousands dollars for speaker cables/line filters but they do not know that increasing capacity(only some ten dollars) improves amplifiers performance more than they do
This is your philosphy.You can use whatever you use.We are both true.
But you are using a very high quality sounded F5 Class A amplifier.This is a push pull class A amplifier.
So why not give some more ten bucks and use higher capacitance?When i add more capacitor i can easily see that bass and treble performance improves.
Some diyers/buyers give hundreds and thousands dollars for speaker cables/line filters but they do not know that increasing capacity(only some ten dollars) improves amplifiers performance more than they do
This is your philosphy.You can use whatever you use.We are both true.
Russellc,
PM Diyaudio member Blues, he has well matched JFets for F5 available.
He has a thread for it, but I can't seem to find it. Him and tech-diy offer excellent service.
PM Diyaudio member Blues, he has well matched JFets for F5 available.
He has a thread for it, but I can't seem to find it. Him and tech-diy offer excellent service.
Russell:
eBay has listings for K170BL/J74BL (matched or not). Unless you want to try K246BL/J103BL, with which I am still struggling the bias.
Tea-Bag:
What kind of black tea do you like? I like the the kind from Ceylon(Sri Lanka).
Like Irish style Black Tea, Macha Green Tea, Twig Tea.
In the winter I drink 3 cups of green tea a day to keep the colds at bay.
Some day I will focus on what a J176 can do as a reasonable P-Channel Substitute. Someday...
In the winter I drink 3 cups of green tea a day to keep the colds at bay.
Some day I will focus on what a J176 can do as a reasonable P-Channel Substitute. Someday...
Thanks for the alley-oop slam dunk T-Bag!
Russellc, please check out my signature below for the wormhole to the thread...
... my work in progress
Replaced the original UI core tranny by a torroid. Prepared the board with the resistors for the psu and also the caps, 22000uF/35V each.
Franz
An externally hosted image should be here but it was not working when we last tested it.
Replaced the original UI core tranny by a torroid. Prepared the board with the resistors for the psu and also the caps, 22000uF/35V each.
Franz
I am asking myself:
as I build a stereo amp and the voltage from the tranny is a little bit to high:
Does it make sense to add per channel separated RC filters?
I have enough of this 22000uF caps and space is also available in the enclosure.
Or is it better not to use electrolytics for this additional RC filters? Some MKP's with 10uF?
Franz
as I build a stereo amp and the voltage from the tranny is a little bit to high:
Does it make sense to add per channel separated RC filters?
I have enough of this 22000uF caps and space is also available in the enclosure.
Or is it better not to use electrolytics for this additional RC filters? Some MKP's with 10uF?
Franz
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Your tranny does not look very big. Is it a 300VA tranny (20V AC x 2)? I agree with Juma that the DC output may be just 25V-26V when idle current is biased to the specified level after amp has been fully burned in and warmed up.
The toroid tranny I used was 400VA (18V AC x 2). Without load it was a little over 25V DC each rail. With load it was 23V DC each rail.
I personally would increase the filter resistors' resistance a little rather than adding another RC filter, if the voltage is really over just a little. In my opinion, another RC filter will make the amp sound dry and dull.
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Umut
The main reason is that I do not like capacitors. However, I cannot do without it. I think it is my problem. By the way, I like the Turkish movie "Pandora's Box", which is a very good movie.
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I like both transistors and capacitors.They are sisters and brothers.Yes the film seems good,i did not watch it completely but i will
Yes, it seems to be a 300VA tranny, guessed from the size. It is out of my parts box.
I will try to arrange the parts in a way, that I can replace it later by a 500VA version, when I think I need it.
I will stick with the original psu design, CRC filtering.
Franz
I finished my (first) F5 amp.
It was a really great diy experience! The result: probably the best amp I've ever built.
All my questions I had are already answered in the 18 pages manual. RTFM...
The only answer I never got: how much is PSRR of the amplifier circuit.
Let's give me the answer by myself: Enough 🙂
Great work, Nelson!
It was a great pleasure to do the initial adjustement using two DVM's at the resistors and one old analogue mili-voltmeter at the output.
The voltages with my tranny are now at 24.6V per rail.
I made this amp for a friend who is driving this speakers with it:
This coaxial two way speakers are built in a Mini Onken enclosure with a very special design:
Before the F5, my friend used a tube buffered LM3886 gainclone or a TK2050 t-amp.
The gainclone was not satisfying in the bass area and the TK2050 produced listening fatigue.
The F5 beats them both, no question. In every aspect.
It is a awesome sounding amp without any hassles. Absolutely dead silent at idle, no power up or power down pops, nothing.
It was one of this famous euphoric moments when we listened the first time to the F5 today, after having it adjusted and measured during two hours in the workshop.
I think, after my vacation I have to build for myself three stereo F5's to drive my active setup.
And to think about airconditioning in my flat...
Just for fun, here a picture I made some years ago, when I made this mini onkens. First bass test with my little daughter (she had a cold at this time and a strong cough).
Nelson: thanks for this nice amplifier!
Franz
It was a really great diy experience! The result: probably the best amp I've ever built.
All my questions I had are already answered in the 18 pages manual. RTFM...
The only answer I never got: how much is PSRR of the amplifier circuit.
Let's give me the answer by myself: Enough 🙂
Great work, Nelson!
It was a great pleasure to do the initial adjustement using two DVM's at the resistors and one old analogue mili-voltmeter at the output.
The voltages with my tranny are now at 24.6V per rail.
I made this amp for a friend who is driving this speakers with it:
An externally hosted image should be here but it was not working when we last tested it.
This coaxial two way speakers are built in a Mini Onken enclosure with a very special design:
An externally hosted image should be here but it was not working when we last tested it.
Before the F5, my friend used a tube buffered LM3886 gainclone or a TK2050 t-amp.
The gainclone was not satisfying in the bass area and the TK2050 produced listening fatigue.
The F5 beats them both, no question. In every aspect.
It is a awesome sounding amp without any hassles. Absolutely dead silent at idle, no power up or power down pops, nothing.
It was one of this famous euphoric moments when we listened the first time to the F5 today, after having it adjusted and measured during two hours in the workshop.
I think, after my vacation I have to build for myself three stereo F5's to drive my active setup.
And to think about airconditioning in my flat...
Just for fun, here a picture I made some years ago, when I made this mini onkens. First bass test with my little daughter (she had a cold at this time and a strong cough).
An externally hosted image should be here but it was not working when we last tested it.
Nelson: thanks for this nice amplifier!
Franz
No, not snow leopard.
Dalmatian fur, synthetical...
It really dissolves the size of the cabinets and makes the speakers looking smaller than they are.
Franz
Dalmatian fur, synthetical...
An externally hosted image should be here but it was not working when we last tested it.
It really dissolves the size of the cabinets and makes the speakers looking smaller than they are.
Franz
Yes! In a room full of snow leopards and/or dalmations it does disappear, now that is a true breakthrough!! 😀 😀
But, seriously, it looks very 60s "modern"...
_-_-bear
But, seriously, it looks very 60s "modern"...
_-_-bear