You are correct Irribeo. The capMx was getting very hot (so were the bridge rectifiers) and my output voltage was abnormally low, way lower than the 4.5v drop associated with the capMx. I removed the capMx and replaced with a conventional linear power supply and the output voltage was normal for a 20v transformer, also the bridge rectifiers get barely warm now.
I am back in the lab after almost a week of absence. Maybe I can stuff the components into the BB tonight? Need to make the +/-35v PSU with the 400VA trafo too if I want to get it to work though.
Getting to sit and listen to my speakers and the Alpha again after a long absence. It's terrible at wasting my time as I find it hard to leave and get work done. Just want to sit and listen to my tunes. Finding that the Cayin N3 with AK4490EQ DAC sounds terrific driving the Aksa Lender pre, driving the ALPHA 20 and a subwoofer amp.
How can one leave this setup? (photo taken when Alpha was on bench getting an input cap upgrade)
Getting to sit and listen to my speakers and the Alpha again after a long absence. It's terrible at wasting my time as I find it hard to leave and get work done. Just want to sit and listen to my tunes. Finding that the Cayin N3 with AK4490EQ DAC sounds terrific driving the Aksa Lender pre, driving the ALPHA 20 and a subwoofer amp.
How can one leave this setup? (photo taken when Alpha was on bench getting an input cap upgrade)
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@maty tinman
Mains DC and Transformers
I´m using VS-60APU06PBF (Mouser 844-60APU06PBF) rectifier diode in the F6 PSU.
The heatsink is one from Fischer Elektronik: I don´t know if the shop delivers outside Germany.
Important point, the heatsink mouting holes are diameter metallized 3.2mm.
I´m using parts from Reichelt:
- V PR118 - 94-M3: Spezialkühlkörper für Clipmontage, 3,2K - W bei reichelt elektronik
- MC 797: Montage-Clip für Kühlkörper TO218, 14,5 mm bei reichelt elektronik
JP
Mains DC and Transformers
I´m using VS-60APU06PBF (Mouser 844-60APU06PBF) rectifier diode in the F6 PSU.
The heatsink is one from Fischer Elektronik: I don´t know if the shop delivers outside Germany.
Important point, the heatsink mouting holes are diameter metallized 3.2mm.
I´m using parts from Reichelt:
- V PR118 - 94-M3: Spezialkühlkörper für Clipmontage, 3,2K - W bei reichelt elektronik
- MC 797: Montage-Clip für Kühlkörper TO218, 14,5 mm bei reichelt elektronik
JP
If I remove capMX and go with basic CRC supply, do I have too high rails for Alpha to handle since I have 2x20v trafo?
Edit; caps in place, now I need to wire them and remove capMX, but I have another trip for weekend, so it'll have to wait 'till next week.
When I can start reworking this frame, I will leave it partly open. Everything with 230v will be shielded and some shielding will be added around pcb's and other live parts as well.
Edit; caps in place, now I need to wire them and remove capMX, but I have another trip for weekend, so it'll have to wait 'till next week.
When I can start reworking this frame, I will leave it partly open. Everything with 230v will be shielded and some shielding will be added around pcb's and other live parts as well.
Attachments
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Hi
If you got a decent VA rating transformer you will get about +/- 24v I think that is still acceptable with 1 pair IRFP240/9240 power mosfet.
I plan to do the same setup.
@JPS64
I thought it was something different, more sophisticated: DC blocking electronic.
Since a few years ago Audio by Van Alstine, aka AVA, uses something similar -without capacitors too- in all its amplifiers (which use big Plitron toroidals).
@xrk971
The BB every time has a more suspicious look. If a neighbor sees your picture maybe calls the ATF
I thought it was something different, more sophisticated: DC blocking electronic.
Since a few years ago Audio by Van Alstine, aka AVA, uses something similar -without capacitors too- in all its amplifiers (which use big Plitron toroidals).
@xrk971
The BB every time has a more suspicious look. If a neighbor sees your picture maybe calls the ATF
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Hi
If you got a decent VA rating transformer you will get about +/- 24v I think that is still acceptable with 1 pair IRFP240/9240 power mosfet.
I plan to do the same setup.
It's 500VA trafo, should be enough? And I also have bigger IXYS devices. Thank you so much, now I can keep going
It's 500VA trafo, should be enough? And I also have bigger IXYS devices. Thank you so much, now I can keep going
Yes, that is OK.
It's 500VA trafo, should be enough? And I also have bigger IXYS devices. Thank you so much, now I can keep going
Can I ask you where did you get the IXPS devices? Did someone ever compare with the IRFP type?
I do have some IRFP at hand (I could use those for PS) at low-Class A amp or Class A/B type. I wait maybe someone will offer some matched sets with the BB.
Of course, bought those devices from mouser. Not the cheapest ones though.. Haven't compared to IRFP's, I just trusted (Aksa's, if I remember right) word that they are good. Amp sounds great as far as I can tell, even my capMx seems to oscillate (?)
Hi Juntuin,
I’m using 2x20v trafo also, when the ALPHA is connected the load drops the voltage to approximately 24vdc. I’d say that’s just about right on the money
Will wait until you test it. Can you do an A/B test between the L & R channel of course in case if you are not set up both channel with the IXPS devices?
Maybe to much power (it not supposed to oscillate because of that) or something else got the best out of the capMx, other people had similar issues. I am a fan of the old style PS. CRC set up. MLytics are exceptional but $$$..
Maybe to much power (it not supposed to oscillate because of that) or something else got the best out of the capMx, other people had similar issues. I am a fan of the old style PS. CRC set up. MLytics are exceptional but $$$..
Hi Juntuin,
I’m using 2x20v trafo also, when the ALPHA is connected the load drops the voltage to approximately 24vdc. I’d say that’s just about right on the money
Thanks for confirmation, Vunce
Too late for A/B testing, amp has been ready for weeks
got it playing just after pcGab.It really seems so. I'm going for CRC too and try capMx with dartzeel, if it works diffirently with class-AB amp (?)
After a weeks of bur-in in the other system, this week I can confirm that Mundor MLytics AGO 47.000uF 125 ºC are very good. Better than the EPCOS 18.000uF 105 ºC (about 30 weeks left until the stock is back according to Mouser) that have replaced in my DC Blocker prototype (I have more DCB but with this EPCOS, very good caps but Mundorf are better).