Having read all 111 pages of this thread, I have decided to go on and build this little head amp. Having decided to use the LM3x7/cap multiplier PSU, I have a couple of questions regarding the power supply:
1. In the manual (F5-HA Description V1.4.pdf) there is a Bill of Materials for the LM3x7/cap multiplier PSU, but I couldn't find the schematic that it is referred to.
2. Regarding the rectifier diodes, is there any difference if using Schottky diodes (e.g., MBR745) instead of soft recovery MSR860?
Thanks a lot
Evangelos
1. In the manual (F5-HA Description V1.4.pdf) there is a Bill of Materials for the LM3x7/cap multiplier PSU, but I couldn't find the schematic that it is referred to.
2. Regarding the rectifier diodes, is there any difference if using Schottky diodes (e.g., MBR745) instead of soft recovery MSR860?
Thanks a lot
Evangelos
Hi Patrick,
Thank you for your response
That's exactly what I had in mind, but I asked because I noticed some discrepancies. So, let me make some guesses.
1. In the BOM there is no input cap before the regulator (3300 μF in the schematic). So, the numbering of the caps in the BOM refers to the actual regulator/cap multiplier.
2. ADJ bypass capacitor (100 μF in the schematic) is now 47 μF.
3. Output capacitor (C6 - 330 μF in the schematic) is omitted, as there is an on-board bypass capacitor in the amp board.
We are the ones to thank you for providing the community with your knowledge and great ideas.
Regards,
Evangelos
Thank you for your response
That's exactly what I had in mind, but I asked because I noticed some discrepancies. So, let me make some guesses.
1. In the BOM there is no input cap before the regulator (3300 μF in the schematic). So, the numbering of the caps in the BOM refers to the actual regulator/cap multiplier.
2. ADJ bypass capacitor (100 μF in the schematic) is now 47 μF.
3. Output capacitor (C6 - 330 μF in the schematic) is omitted, as there is an on-board bypass capacitor in the amp board.
We are the ones to thank you for providing the community with your knowledge and great ideas.
Regards,
Evangelos
The BoM refers to the parts required to populate Ca Multiplier PCBs from us.
Nothing holly.
You are free to try something else as it pleases you.
And you should also perhaps check the F5HA Build thread at the Pass forum for any updates from the Beta testers.
http://www.diyaudio.com/forums/pass-labs/283387-f5-ha-build-thread.html
Patrick
Nothing holly.
You are free to try something else as it pleases you.
And you should also perhaps check the F5HA Build thread at the Pass forum for any updates from the Beta testers.
http://www.diyaudio.com/forums/pass-labs/283387-f5-ha-build-thread.html
Patrick
sorry i havent yet messed with the sim but i haven been fiddling with my physical build quite a bit. 
i notice that the even order harmonic increases if the positive rail's voltage is higher than the negative rail's. could someone please elaborate why that is, if my observation is right?
and can i add p3 adjuster much like one in F5 and BA-3 to this headphone circuit to tweak the harmonic profile?
here's BA-3 circuit for reference.
i notice that the even order harmonic increases if the positive rail's voltage is higher than the negative rail's. could someone please elaborate why that is, if my observation is right?
and can i add p3 adjuster much like one in F5 and BA-3 to this headphone circuit to tweak the harmonic profile?
here's BA-3 circuit for reference.
I can only second Patrick, Fred!
One day you will be tired from travelling, and then you want to sit down in your favourite recliner
and listen to some good music via your headphones and a really good headphone amp...
Taking this chance to post a few images of my finished F5HA (finished months ago, only added the decals...). Sounding superb!
Err, that one took longer than 3 days to build.
One day you will be tired from travelling, and then you want to sit down in your favourite recliner
and listen to some good music via your headphones and a really good headphone amp...
Taking this chance to post a few images of my finished F5HA (finished months ago, only added the decals...). Sounding superb!
Err, that one took longer than 3 days to build.
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