Will most likely work , but at a crude level. Offset will be present,
crude thermal tracking , same as this amp...
http://www.diyaudio.com/forums/showthread.php?s=&threadid=142291
With current sources , a real Vbe , triple EF and proper compensation you have this :
http://users.ece.gatech.edu/~mleach/lowtim/
Thousands have built the good professor's design , so it is valuable reading for this particular topology.
OS
crude thermal tracking , same as this amp...
http://www.diyaudio.com/forums/showthread.php?s=&threadid=142291
With current sources , a real Vbe , triple EF and proper compensation you have this :
http://users.ece.gatech.edu/~mleach/lowtim/
Thousands have built the good professor's design , so it is valuable reading for this particular topology.
OS
WE could call this "Leach Amp Done Badly".
No emitter resistors on the outputs. No proper output stage biasing. No current sources on the LTP's... not to mention exposing the LTP transistors to the full rail voltage without cascodes. Oh, and 2 pairs of flatpack outputs on 63V? I dont think so.
The PCB layout is atrocious. The bias diodes aren't even on the heatsink! I'd be surprised if it actually worked for more than 5 minutes.
No emitter resistors on the outputs. No proper output stage biasing. No current sources on the LTP's... not to mention exposing the LTP transistors to the full rail voltage without cascodes. Oh, and 2 pairs of flatpack outputs on 63V? I dont think so.
The PCB layout is atrocious. The bias diodes aren't even on the heatsink! I'd be surprised if it actually worked for more than 5 minutes.
Hi There
Thanks a lot of all experts for their valuable feedback. here is another amp diagram found over the net. Please`tell me about this. Is it worth to develop this amplifier.
Can anyone tell me:
can I use NPN and PNP transistors instead of N-channel and P-channel mosfets? I mean is there any difference between them?
like they are using (N)2sk1058 and (P)2sj162, can I use C4468 and A1695?
Regards
you can view the complete project here
http://diyaudiotr.com/islecler/tammetin.php?metinid=7
Thanks a lot of all experts for their valuable feedback. here is another amp diagram found over the net. Please`tell me about this. Is it worth to develop this amplifier.
Can anyone tell me:
can I use NPN and PNP transistors instead of N-channel and P-channel mosfets? I mean is there any difference between them?
like they are using (N)2sk1058 and (P)2sj162, can I use C4468 and A1695?
Regards
you can view the complete project here
http://diyaudiotr.com/islecler/tammetin.php?metinid=7
Attachments
the ammount of power
stated in both of these circuits are only theoretical
you will vever be able to produce this ammount of power in a reactive load such is a speaker
the nico ras amplifier is by far better than the one originaly posted but will never make this numbers of 380w at 4 ohms and working for a long time probably as a pa amplifier ....
cheap power is not an easy thing
it would be better to state your application and then a circit is going to be sugested
finally NO YOU CANNOT REPLACE MOSFETS WITH SIMPLE BJT A1695 AND 4468 !!!!
by this i can tell that your expirience must be very low and high power amplifiers are not an easy thing for a beginer ....
stated in both of these circuits are only theoretical
you will vever be able to produce this ammount of power in a reactive load such is a speaker
the nico ras amplifier is by far better than the one originaly posted but will never make this numbers of 380w at 4 ohms and working for a long time probably as a pa amplifier ....
cheap power is not an easy thing
it would be better to state your application and then a circit is going to be sugested
finally NO YOU CANNOT REPLACE MOSFETS WITH SIMPLE BJT A1695 AND 4468 !!!!
by this i can tell that your expirience must be very low and high power amplifiers are not an easy thing for a beginer ....
Re: the ammount of power
Hi Thanks for the reply. You are right I am not an electronics guy
but I have a hobbit to ask questions.
I have built 3 high power amps and they are working very well. Like Nmos350 / 500.
Once I built a small amp with the same topology and that amplifier works really well; with 32VDC rail it produces something like 180W rms into 4ohm load. Although I do not have any equipment to judge the expect power but I compare it with my UCD Class D amplifier. That's why I thought with 55VDC rail this nico ras amplifier might give good power.
Regards
sakis said:
Hi Thanks for the reply. You are right I am not an electronics guy
but I have a hobbit to ask questions. I have built 3 high power amps and they are working very well. Like Nmos350 / 500.
Once I built a small amp with the same topology and that amplifier works really well; with 32VDC rail it produces something like 180W rms into 4ohm load. Although I do not have any equipment to judge the expect power but I compare it with my UCD Class D amplifier. That's why I thought with 55VDC rail this nico ras amplifier might give good power.
Regards
off the cuff amp,s
Lot,s of good amp's out their to restore, amp,s to build, with pcboard's available, amp's to improve on, for sell, read through the schematic's that are avalible online !! that will give you a good idea, personaly I would rather find a good amp to modifi,like SAKIS reply change the signal cap's , use computer grade or switching power supply , high rippel type in power supply.
why build from scratch, all that time?? , let the pro's and feen's do the hard work , buy a drill press , soldering iron, find something to assemble, or modifi, maybe one that part's are avalible for !!
grab a used QSC pro amp , get schamitics from their web site strip it from it's noisy fan cooled case, then you will be ready to start building a cheap realible amp , that has parts avalible , service manual's great circut's to start with, room to improve.
Lot,s of good amp's out their to restore, amp,s to build, with pcboard's available, amp's to improve on, for sell, read through the schematic's that are avalible online !! that will give you a good idea, personaly I would rather find a good amp to modifi,like SAKIS reply change the signal cap's , use computer grade or switching power supply , high rippel type in power supply.
why build from scratch, all that time?? , let the pro's and feen's do the hard work , buy a drill press , soldering iron, find something to assemble, or modifi, maybe one that part's are avalible for !!
grab a used QSC pro amp , get schamitics from their web site strip it from it's noisy fan cooled case, then you will be ready to start building a cheap realible amp , that has parts avalible , service manual's great circut's to start with, room to improve.
IF SHIPPING WAS NOT SO EXPENSIVE I WOULD SEND YOU ONE OF MY AMP'S THAT ARE JUST LAYING ARROUND, I FORGET THAT YOU DON'T LIVE IN THE USA, WHERE AUIDO GEAR CAN BE FOUND DIRT CHEAP IN PAWN SHOP'S AND CRAIG'S LIST, I BUY SELL AMP'S ALL WEEK LONG, SORRY TO GET YOU SIDE TRACTED.
HAVE ALLWAY'S CUT DEALS ON AMP'S BUT ONLY BUY SELL TRADE ONE'S THAT SERVICE MANUAL'S ARE AVALIBLE FOR. SAME WITH BUILDING THEM ' YOU NEED UP TO DATE SCHEMATIC'S AND PART,S AVALIBILTY, NEW SEMI CONDUCTOR'S HELP TO.
HOW MANY OF YOU HAVE HAD TO FIND THOSE RING EMITTER TRANSISTER'S USE'D IN THE AMPIZZILA ? OR THAT BIAS' IC CHIP ??
HAPPY BUILDING !!!
HAVE ALLWAY'S CUT DEALS ON AMP'S BUT ONLY BUY SELL TRADE ONE'S THAT SERVICE MANUAL'S ARE AVALIBLE FOR. SAME WITH BUILDING THEM ' YOU NEED UP TO DATE SCHEMATIC'S AND PART,S AVALIBILTY, NEW SEMI CONDUCTOR'S HELP TO.
HOW MANY OF YOU HAVE HAD TO FIND THOSE RING EMITTER TRANSISTER'S USE'D IN THE AMPIZZILA ? OR THAT BIAS' IC CHIP ??
HAPPY BUILDING !!!
AMP007, please take your caps lock off. We're not deaf you know
Re: Re: the ammount of power
I wish I had a hobbit to ask questions.
..Todd
Wasim said:You are right I am not an electronics guy
I wish I had a hobbit to ask questions.
An externally hosted image should be here but it was not working when we last tested it.
..Todd
Forget the cap's lock protocall , after all , have been kicked off a zx14 web site for posting a photo of my zx14 up a jeep trail, freaked out a few drag racer's, had to modifi a brand new QSC ,GX3 just to prove it could be done , a challenge from their website. will be more carefull in the future, lot's of good info here,yes my eye's are 56 years old , my ear's even older,1200 watt's in liveing room, zx14 in carport, eye surgery laser's torn apart in back yard!
post very littel to many toy's , Thank's for even leting me in.
post very littel to many toy's , Thank's for even leting me in.
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