High Power GC pics
My little BPA300+ uses 6 LM3875 per channel at +/- 40VDC power rails.
232WPC@8ohms
336WPC@4ohms
My little BPA300+ uses 6 LM3875 per channel at +/- 40VDC power rails.
232WPC@8ohms
336WPC@4ohms
An externally hosted image should be here but it was not working when we last tested it.
High Power GC pics
Another inside view.
Another inside view.
An externally hosted image should be here but it was not working when we last tested it.
High Power GC pics
The front.
The front.
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High Power GC pics
The back without the silk screen,
The back without the silk screen,
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CJ900RR said:This has been playing in my home for 2 months now.
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2 X homemade LM3875-boards
togheter with a homemade preamp, currently using a OPA2277
sound is good, but im thinking about making a case for it 😀
Enough about the case, how about that power supply ? (!)
superhkm said:
Enough about the case, how about that power supply ? (!)
What about it 🙂 My dog doesnt pee on it anymore 😀
Its a 11 kg heavy tranny salvaged from an old machine at work, with 2 x 15V, 2 x 25V and 2 X 40 volt. Have no clue about VA-rating but my guess is that its more than enough.
Each channel as 2 x 20.000uF plus one 10.000uF in caps. All high voltage (230V) is secured and cant be touched without using violence.
Power supply schematic
here it is, all values are application specific.
here it is, all values are application specific.
An externally hosted image should be here but it was not working when we last tested it.
CJ900RR said:
What about it 🙂 My dog doesnt pee on it anymore 😀
Its a 11 kg heavy tranny salvaged from an old machine at work, with 2 x 15V, 2 x 25V and 2 X 40 volt. Have no clue about VA-rating but my guess is that its more than enough.
Each channel as 2 x 20.000uF plus one 10.000uF in caps. All high voltage (230V) is secured and cant be touched without using violence.
I'm happy for your dog...🙂
But I'm not used to seeing such huge caps in front of a gainclone, have you tried with smaller / less ?
ha trevligt !
Yes I have tryied with smaller caps, and without anyone at all. For thoose loudspeakers at my pictures I dont really need that big ones, but at my other loudspeakers (Canton LE109), I think that it makes a prefered difference.superhkm said:
I'm happy for your dog...🙂
But I'm not used to seeing such huge caps in front of a gainclone, have you tried with smaller / less ?
ha trevligt !
But I have been thinkin of reducing it down to only 10.000uF, beacase I most turn off my tv before starting the amp, or else i blow my fuses 😉
Ha det trevligt själv 🙂
AC Filter Inductors
Halo,
Please look at the orientation of the two Ls in the AC Filter. They are going from line and neutral, respectively to ground. Shouldn't they be in series with line and neutral and be mutually coupled?
Steve
Halo,
Please look at the orientation of the two Ls in the AC Filter. They are going from line and neutral, respectively to ground. Shouldn't they be in series with line and neutral and be mutually coupled?
Steve
N-Channel thank you very much, could have given somebody a nasty surprise, I put the schematic together a little to quicky when somebody asked all I had was a printed. The corrected version is above now and looked it over to make sure I didnt make any other rushed mistakes.
N-channel: " ... look at the orientation of the two Ls in the AC Filter. They are going from line and neutral, respectively to ground. Shouldn't they be in series with line and neutral and be mutually coupled? ..."
The partial diagram is very similar to laboratory gear line filters ... a tank circuit with two inductors and several caps (& resistors), filtering any noise riding in on the power cord.
😉
The partial diagram is very similar to laboratory gear line filters ... a tank circuit with two inductors and several caps (& resistors), filtering any noise riding in on the power cord.
😉
Attachments
" ... refresh your page, the corrected version is there ..."
A very good job ... I'll bet your power supply is just about as clean as is possible. The (newer) diagram is now quite clear as well.
Wondering: Did you build this entirely from your own design(s)? ... using parts from other amps or purchased "new" ? ...
Also: Noticing the double diode, full wave bridge ... What type ?? (1n4004 or other?)
Would it be possible to see a 'scope trace of the power supply output?? (Or some kind of measurement indication of what little ripple there is ??)
Great job, great design ... 😀
A very good job ... I'll bet your power supply is just about as clean as is possible. The (newer) diagram is now quite clear as well.
Wondering: Did you build this entirely from your own design(s)? ... using parts from other amps or purchased "new" ? ...
Also: Noticing the double diode, full wave bridge ... What type ?? (1n4004 or other?)
Would it be possible to see a 'scope trace of the power supply output?? (Or some kind of measurement indication of what little ripple there is ??)
Great job, great design ... 😀
Re: Inside
Very nice construction, but what is the function of all these caps on the bridges?
enzedone said:Here's a pic of the inside
Very nice construction, but what is the function of all these caps on the bridges?
Power supply ?'s
FastEddy, The Amp is all new I do my own boards ect... as for the power supply its basically my takeoff on various others.
The Diods are 6amp fast recovery diods from faichild semi I dont remember the part #, but could look it up. Ive tried ultra fast diodes but cant tell a major difference Some people sware by the MUR series.
I never put the supply on the scope didnt really see a reason, but it should be pretty clean probably better then alot of regulated ones.
mariofer, By useing many smaller faster lower ESR caps you get the benifts of large storage and better faster control.
FastEddy, The Amp is all new I do my own boards ect... as for the power supply its basically my takeoff on various others.
The Diods are 6amp fast recovery diods from faichild semi I dont remember the part #, but could look it up. Ive tried ultra fast diodes but cant tell a major difference Some people sware by the MUR series.
I never put the supply on the scope didnt really see a reason, but it should be pretty clean probably better then alot of regulated ones.
mariofer, By useing many smaller faster lower ESR caps you get the benifts of large storage and better faster control.
Re: Power supply ?'s
Sorry, but I was asking about a pic posted a few months ago by enzedone:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=79303&perpage=10&pagenumber=6
In the pic you can see four poliester caps over the bridge. And I wondered why (¿?)
halo0925 said:mariofer, By useing many smaller faster lower ESR caps you get the benifts of large storage and better faster control. [/B]
Sorry, but I was asking about a pic posted a few months ago by enzedone:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=79303&perpage=10&pagenumber=6
In the pic you can see four poliester caps over the bridge. And I wondered why (¿?)
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