thank man 🙂 if I made the Sprint file you don't mind if I share the files here so other can have it a and try it out 😉
Best Regards
Juan
Hey!. Its all for share and its all Mr. Miles design. Thats why I posted eagle files. Sure go ahead. You will will make a beautiful job of it, I am sure. Here are the updated protect eagle files.
Already populating 3-pair DC servo mosfet amp. Awaiting some components😱. Once tested I will share those files too, for DIY.🙂
reg
Prasi
Attachments
I will make Sprint 6 file for friends here so they can have fun 🙂 thanks for sharing sir
Best Regards
Juan
Something to keep in mind with this PSU is that the filter section is just a simple two cap filter. The beauty of it is that the speaker protection is included.
Yes. My feeling is PSU can be improved. e.g. quasimodo circuit (suggested by rsavas), higher filter capacitance in CRC configuration and MUR1560 diodes + some local decoupling, it could be much better. Mr. Miles can suggest/ make improvements.
reg
Prasi
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I believe this combination F100/F100-PSU was designed for PA use so ultra clean filtering was not the goal. I think durability, power and compactness was the rule. This PSU has an additional 24v out for a fan and also a +-12-15V out to supply a pre or something. A very useful setup just not ultra clean. Of course there is nothing stopping someone from upping the filter caps to higher values if desired.
Blessings, Terry
Blessings, Terry
Yes F100/F100-PSUwas designed for PA and there is clip leds and OCL protect...
Hello
greetings tested the AX14 2 pair version happy with the results can the F100
power supply be used with it mainly looking for the overcurrent protection
warm regards
Andrew
greetings tested the AX14 2 pair version happy with the results can the F100
power supply be used with it mainly looking for the overcurrent protection
warm regards
Andrew
Tested the amp. sound is nice, neutral (only test speakers now). I didnt have proper ceramic caps, used 22p instead of 10 p across the MPSA B-C. The blue ceramic caps used are 1kV and dont know if they are suitable.
three problems,
1. there is hiss when sound is muted. should I remove the 2r2 ground lift and connect i/p ground directly to psu?😕
2. during changeover from one music track to next track, there is a thump noise. 😕😕
3. minor problem is that there is a start thump, which a speaker delay will eliminate.
reg
Prasi
Attachments
Is there DC on the output when the input is shorted? Does the hiss go away with the input shorted?
DC offset with the i/p shorted is 0.6 mV. And yes, there is same amount of hiss even when i/p is shorted.
The hiss/hum I am talking about, to hear it, I need to be pretty close to the speaker ~10-15 cm.
The thump is likely coming from your source. I have a cheap DA converter that does the same thing.
Hiss can be harder to locate. It could be oscillation. A scope reading of the noise helps.
Hiss can be harder to locate. It could be oscillation. A scope reading of the noise helps.
Yes, you are right. The thump (during track change) gone when I changed the source (mobile). Funny thing, I had used the same source , for my previous builds w/o such a problem.
It still sounds like a grounding issue. Try running a wire from input ground to star ground and see if anything changes.
Removing the 2r2 and connecting i/p gnd to psu gnd solved the problem. There is still a minor hum when ear is next to woofer, but not audible even from 10cm away.
connected to proper speakers, slight start-up thump, other than that no unwanted behavior. sound is very nice. bass is good 
Once I get correct value NPO/C0G caps, I will change to the recommended values and install rest of the pairs and listen again.
bias that I set-up is 32mV across the emitter resistor pair, everything is cool🙂.
even with only single pair, with 32V supply, its loud !, even at very low pot volume setting. I can only imagine what will happen at 3 pairs, 70V .
reg
Prasi
connected to proper speakers, slight start-up thump, other than that no unwanted behavior. sound is very nice. bass is good
Once I get correct value NPO/C0G caps, I will change to the recommended values and install rest of the pairs and listen again.
bias that I set-up is 32mV across the emitter resistor pair, everything is cool🙂.
even with only single pair, with 32V supply, its loud !, even at very low pot volume setting. I can only imagine what will happen at 3 pairs, 70V .
reg
Prasi
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Hello apexaudio
greetings F100 #30 schematic and FX100 #540 SCHEMATIC i see changes in
schematic values is #540 is it new modified schematic i want to use it with
2 pair AX14 my transformer 40 0 40 AC
warm regards
Andrew
greetings F100 #30 schematic and FX100 #540 SCHEMATIC i see changes in
schematic values is #540 is it new modified schematic i want to use it with
2 pair AX14 my transformer 40 0 40 AC
warm regards
Andrew
Thanks Mr. Mile for letting me know.
As I said I will install rest of the pairs, correct caps and then listen again.
Should I increase the bias, as these are MOSFETS. Currently, I have it at 32 mV across the emitter resistor pair.
reg
Prasi