this is not a bad amplifier
and like many uses 2SK1058 + 2SJ162 output
RAS-300 MOSFET Power Amp
Thanks
and like many uses 2SK1058 + 2SJ162 output
RAS-300 MOSFET Power Amp
Thanks
lineup said:this is not a bad amplifier
and like many uses 2SK1058 + 2SJ162 output
RAS-300 MOSFET Power Amp
Thanks
Hi Lineup
this is not a 300 watt amp by a long shot. The web that you referring to hi-jack some text and my circuit from my web-pages. I have asked them to remove it but this is to no avail.
The amp that you see there would be good for between 100 -130 watt. To achieve higher power ratings the transistors have to br changed to MJE340/350 and MPSA42/92. Also double up on the MOSFETs then you can run at 65V
Apologies Lineup, I see now that they have published the right amplifier.
Previously they had the 100 watt single pair output. With The MPSA06/56 and BD139/140 the supply should not be higher than about +-55V to keep on the safe side.
Under the above conditions the amp will provide you with about 156 watt rms into 8 ohms and about 240 watt into 4 ohms.
Many has been built and I have not had any comments that it sounded or performed badly. I have since improved the design adding a CCS and current mirror. Although it has improved measured specs, I cannot say that it improved what it sounded like.
This amp as I understand from some constructors can take punishment used in sound reinforcement systems (clubs in other words).
Previously they had the 100 watt single pair output. With The MPSA06/56 and BD139/140 the supply should not be higher than about +-55V to keep on the safe side.
Under the above conditions the amp will provide you with about 156 watt rms into 8 ohms and about 240 watt into 4 ohms.
Many has been built and I have not had any comments that it sounded or performed badly. I have since improved the design adding a CCS and current mirror. Although it has improved measured specs, I cannot say that it improved what it sounded like.
This amp as I understand from some constructors can take punishment used in sound reinforcement systems (clubs in other words).
lineup said:this is not a bad amplifier
and like many uses 2SK1058 + 2SJ162 output
RAS-300 MOSFET Power Amp
Thanks
Hi Lineup,
e-mail me and I will send you the real thing for comment. I would like to hear what you say.
Kindest regards
Nico
I am sorry about they fool us.Nico Ras said:
Did not know it was stolen stuff from your website.
-------------------
Better go directly to your website to get good info.
http://www.digisec.co.za/ras/
This MOSFET AMP is one version for >100 Watt:
An externally hosted image should be here but it was not working when we last tested it.
http://www.digisec.co.za/ras/ras250/ras250.html
I don't think anybody "rips off" any designs around here..,
we only "Port" them.
As far as this design goes.. 12 years ago..
HH (UK)was (almost) the first with this topology (hitachi app notes ,late 80's)
With 5 PAIRS this particular amp was only rated at 300/8R -
600/4R.. so the earlier "ripoff " seems to be far from accurate.
OS
we only "Port" them.
As far as this design goes.. 12 years ago..
An externally hosted image should be here but it was not working when we last tested it.
HH (UK)was (almost) the first with this topology (hitachi app notes ,late 80's)
With 5 PAIRS this particular amp was only rated at 300/8R -
600/4R.. so the earlier "ripoff " seems to be far from accurate.
OS
Yes, that one & similar has been around very long.
Often with Hitachi 2SK134 / 2SJ49 series for output.
See this topic and my attachment
http://www.diyaudio.com/forums/showthread.php?postid=1098779#post1098779
Good old MOSFET lateral 2SK134 / 2SJ49 Amplifier:
Often with Hitachi 2SK134 / 2SJ49 series for output.
See this topic and my attachment
http://www.diyaudio.com/forums/showthread.php?postid=1098779#post1098779
Good old MOSFET lateral 2SK134 / 2SJ49 Amplifier:
Attachments
The book is one Babani from 1991
by R. Penfold
http://www.babanibooks.com/
Buy Amazon:
High-Power-Audio-Amplifier-Construction
http://www.amazon.com/High-Power-Audio-Amplifier-Construction/dp/0859342220
by R. Penfold
http://www.babanibooks.com/
Buy Amazon:
High-Power-Audio-Amplifier-Construction
http://www.amazon.com/High-Power-Audio-Amplifier-Construction/dp/0859342220
Here is the real >300 watt into 4 ohm version I have never posted before.
I don't make money with it so it really does not matter. What I will say is that I have modified the CCS to that Alex has suggested and it works pretty nicely. Thanks Alex hope you don't mind.
I have Gerbers of the PBCs if anyone is interested. I do not make or sell kits, PCBs, transformers or components, you may do with the circuit as you please.
This one has been made for my friend running the local country club for New Year's eve party, eight channels - installed and cranked up and tested for 5 hours - not bad at all.
I built mono blocks into my standard class A amp very simple case. Heat sinks are for our standard rectifier extrusions used in 500 Amp chargers @ 0.15w/deg C times 4.
Amps are placed at each Altec Lansing 22 inch with horn mid and horn tweeter- Connections to source are mono via RF audio extenders, to the mixing console. These speakers and amps are permanent installations near the ceiling about 3.5 -4 meters high.
The hall is about 60 x 40 m and running all is ******* deafening but he is expecting around 600 people which will change matters dramatically.
You can change this amp, make it better or worse, do whatever you guys please - it is now in the public domain.
Kindest Regards
Nico
Link is below:
http://digisec.co.za/ras/music/300w MOSFET AMP.pdf
I don't make money with it so it really does not matter. What I will say is that I have modified the CCS to that Alex has suggested and it works pretty nicely. Thanks Alex hope you don't mind.
I have Gerbers of the PBCs if anyone is interested. I do not make or sell kits, PCBs, transformers or components, you may do with the circuit as you please.
This one has been made for my friend running the local country club for New Year's eve party, eight channels - installed and cranked up and tested for 5 hours - not bad at all.
I built mono blocks into my standard class A amp very simple case. Heat sinks are for our standard rectifier extrusions used in 500 Amp chargers @ 0.15w/deg C times 4.
Amps are placed at each Altec Lansing 22 inch with horn mid and horn tweeter- Connections to source are mono via RF audio extenders, to the mixing console. These speakers and amps are permanent installations near the ceiling about 3.5 -4 meters high.
The hall is about 60 x 40 m and running all is ******* deafening but he is expecting around 600 people which will change matters dramatically.
You can change this amp, make it better or worse, do whatever you guys please - it is now in the public domain.
Kindest Regards
Nico
Link is below:
http://digisec.co.za/ras/music/300w MOSFET AMP.pdf
Attachments
This is image of 100 WAtt MOSFET, at Nico Ras homepage
.
An externally hosted image should be here but it was not working when we last tested it.
Hi Nico,
Looks very interesting and I want to build the 100W amp with your upgrades. Will it be a problem to mail the PCB and the construction details to my mail ID or just share it here on the forum. Would like to have your response as I would like to restore my old Mini0Crescendo Amps which have failed ( After 20 Years -the olde trusty SK135/SJ49....was a great amp till it lasted)
Regards
Ravi Kumar Rao
ravi.rao.kumar@gmail.com
Looks very interesting and I want to build the 100W amp with your upgrades. Will it be a problem to mail the PCB and the construction details to my mail ID or just share it here on the forum. Would like to have your response as I would like to restore my old Mini0Crescendo Amps which have failed ( After 20 Years -the olde trusty SK135/SJ49....was a great amp till it lasted)
Regards
Ravi Kumar Rao
ravi.rao.kumar@gmail.com
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