But, it's a gift for my wife. I was really hoping for her Valentine's gift. 💝
^
You know, we are planning on retiring and that means her work stuff is gonna go away.
So, she'll get room in her home office.
If I put a 55" OLED in her office, with a Roku... hmm.... I could exile her from the den, watching TV all the time, so I could play the stereo out in the living room during the day.
I wrote giving her an amp in jest ( but you know that) ... but, but... right now she's got a pair of Elac Unifi 2 UB52 speakers with a Nuforce DDA120 and bluetooth. She seldom uses it, but if I got the TV and Roku in that room, hmm... I could give her the comfy Italian mid century chair I got in my office... but I don't use...
I still need the F5m though, to keep the F5 company.
Anyhow, back to our scheduled topic. ;-D
You know, we are planning on retiring and that means her work stuff is gonna go away.
So, she'll get room in her home office.
If I put a 55" OLED in her office, with a Roku... hmm.... I could exile her from the den, watching TV all the time, so I could play the stereo out in the living room during the day.
I wrote giving her an amp in jest ( but you know that) ... but, but... right now she's got a pair of Elac Unifi 2 UB52 speakers with a Nuforce DDA120 and bluetooth. She seldom uses it, but if I got the TV and Roku in that room, hmm... I could give her the comfy Italian mid century chair I got in my office... but I don't use...
I still need the F5m though, to keep the F5 company.
Anyhow, back to our scheduled topic. ;-D
Eons ago Pa experimented with th’s in PSU’s. However they are all a bit different from each other. That problem is not that relevant when needing only one of them, such as in this case. Very cool!
I had my F5 experience an issue during UPS shipping. One of the thermistors that are supposed to touch the heat sink became mechanically loosened and wasn't making very good contact with the heat sink.
It was hard to see, you had to use a magnifying lens to see it. So, needless to say, that one amp got a real "smoke" test.
Those things need to have a mechanical connection to hold them in place during shipping... or at the very least, always check them when you receive them.
I keep wondering how UPS does it.... how can they bend heatsinks without the box showing any damage?
It was hard to see, you had to use a magnifying lens to see it. So, needless to say, that one amp got a real "smoke" test.
Those things need to have a mechanical connection to hold them in place during shipping... or at the very least, always check them when you receive them.
I keep wondering how UPS does it.... how can they bend heatsinks without the box showing any damage?
The 5Fm is simplified;
1) how about reducing the source resistors to zero?
That simplification would be possible with various lateral Fets.
How would that have an effect on harmonics? I expect increase of 3rdH????
2) how about parallelling? Turbo?
- questions relevant in converting the existing F5 to the new style.
1) how about reducing the source resistors to zero?
That simplification would be possible with various lateral Fets.
How would that have an effect on harmonics? I expect increase of 3rdH????
2) how about parallelling? Turbo?
- questions relevant in converting the existing F5 to the new style.
Not to go off too much on a tangent... what are the THD qualities of the F5T v2 and v3 when compared to the base amp?
If the F5m has more 2nd harmonic than the F5... and the turbos have more 3rd order ( I'm guessing ) will that mean that the F5mT amps will sound the most like a plain F5 with more power?
If the F5m has more 2nd harmonic than the F5... and the turbos have more 3rd order ( I'm guessing ) will that mean that the F5mT amps will sound the most like a plain F5 with more power?
It is astonishing how many lives the F5 has.
Many yet to be discovered it seems.
Many yet to be discovered it seems.
Not-quite-the-build-guide configuration, but pretty close. This isn't the final PSU board, (there was a rev needed) and I need to re-code the wiring colors instead of use what I can dig out of my drawers, get everything squared up and dressed a little prettier.
It works great and sounds beguiling, this is going to be a popular build.
😎
(And for those interested, it's an Omega bracket from Toroid of Maryland. https://toroid.com/omega-bracket-vertical-mount/ )
It works great and sounds beguiling, this is going to be a popular build.
😎
(And for those interested, it's an Omega bracket from Toroid of Maryland. https://toroid.com/omega-bracket-vertical-mount/ )
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[Edited] I'm very interested to understand why only one secondary is rectified. I'm probably the only one scratching my head as I'm still pretty much a noob here......(edit) hand to face...center tapped per article.
Nice 6L6!
Especially the trafo bracket 😉
Especially the trafo bracket 😉
It’s not one secondary, the dual secondaries are configured as full wave bridge Center Tap. You only need one rectifier block.
Nelson talks about it in the F5m article and I’ll make sure to cover it in the guide.
I believe this is what is going on (very simplified version) Only instead of discrete diodes, it is a bridge rectifier. Another awesome way of simplifying an already super simple design. This does bring the question, why did the DIYaudio power supply boards in the store opt to use 8 diodes as opposed to 4 on the diode section? Is there a performance advantage.
With the center tap at ground, you only need one bridge to get a bipolar (+/-) supply.
You could use one bridge per secondary of course, this has the advantage of being simple and inexpensive.
You could use one bridge per secondary of course, this has the advantage of being simple and inexpensive.