Hi Tibi
You should try using OPA134 instead. The MOS125 uses it.
As for the output, you could use IRFP240/9240 as these are cheaper. Off course some passive components needs to be changed.
If you are still interested with the MOS125, send me a private email. I can try to help you with the pcb layout which is crirtical as said by the designer.
Discrete is your prefered option, and with the PSU you have, than I would advice you to go for Nmos200 (by Quasi). It is easy to build and sounds very good with IRFP450.
Cheers.......Raj
You should try using OPA134 instead. The MOS125 uses it.
As for the output, you could use IRFP240/9240 as these are cheaper. Off course some passive components needs to be changed.
If you are still interested with the MOS125, send me a private email. I can try to help you with the pcb layout which is crirtical as said by the designer.
Discrete is your prefered option, and with the PSU you have, than I would advice you to go for Nmos200 (by Quasi). It is easy to build and sounds very good with IRFP450.
Cheers.......Raj
If you fancy discreste may I suggest my Mosfet amp, which uses laterals,
http://www.diyaudio.com/forums/show...d=119151&highlight=my+mosfet+amp+designed+for
I can promise you will not be dissappointed. Still have not heard anything to better it, 100% stable and uses easy to obtain parts 🙂
http://www.diyaudio.com/forums/show...d=119151&highlight=my+mosfet+amp+designed+for
I can promise you will not be dissappointed. Still have not heard anything to better it, 100% stable and uses easy to obtain parts 🙂
Hi,
without trying to influence anybody`s decision...
1) I would instantly abandon this design and go for discrete topology.
2) I would ensure the drivers have an operating frequency range of well above 300MHz.
without trying to influence anybody`s decision...
1) I would instantly abandon this design and go for discrete topology.
2) I would ensure the drivers have an operating frequency range of well above 300MHz.
of course
you may use also parts from mobile telephones they can easilly work up to 2GHZ frecuency ......
use of these kind of transistors is not the only way to make a good amplifier there are other things related also ....
Lumba Ogir said:
you may use also parts from mobile telephones they can easilly work up to 2GHZ frecuency ......
use of these kind of transistors is not the only way to make a good amplifier there are other things related also ....
following is what the picture in the data sheet looks like. notice the logo looks differnt than your op amp. logos are copyrighted and registered trademarks. they are never simplified to the point of the laser etching on your device, unless you see it in print on the manufacturer's data sheet. whether in white ink as shown, or laser etched, the logo should be identical. also check TI's website and find out what their date code structure is. i'm pretty sure it's just 4 digits, and not that long alphanumeric mumbo jumbo shown. also the real burr brown logo has a circle R next to it, the fake doesn't. and the actual part number is supposed to be marked OPA604AP
Attachments
o..... but of course
presuming that you can listen good enough up to 2GHZ...then you may trust me !!!!
these devices can produce sound with a frecuency of 2GHZ the only thing you need to do is listen carefully and you will hear them .....
that was a joke ..... and honestly i had enough with it .....
the point here was to tell you that the first NAD amplifiers we listen too had 2N3055 on them that were good up to 800 khz if i remember well but may be iam wrong
nad was a hell of a good amplifier for the time ..... now days you have modern circuits that will out perfom NAD for breakfast
seek for simplicity, prooven designs, and asl ong that you go for diy choose something that has a lot of support behind it
300 MHZ TRANSISTORS WILL DO YOU ABSOLUTELLY NOTHING IF THE REST LIKE PCB SCHEMATIC AND SO ON IS NOT CORRECT ALSO ....
friendlly regards sakis
presuming that you can listen good enough up to 2GHZ...then you may trust me !!!!
these devices can produce sound with a frecuency of 2GHZ the only thing you need to do is listen carefully and you will hear them .....
that was a joke ..... and honestly i had enough with it .....
the point here was to tell you that the first NAD amplifiers we listen too had 2N3055 on them that were good up to 800 khz if i remember well but may be iam wrong
nad was a hell of a good amplifier for the time ..... now days you have modern circuits that will out perfom NAD for breakfast
seek for simplicity, prooven designs, and asl ong that you go for diy choose something that has a lot of support behind it
300 MHZ TRANSISTORS WILL DO YOU ABSOLUTELLY NOTHING IF THE REST LIKE PCB SCHEMATIC AND SO ON IS NOT CORRECT ALSO ....
friendlly regards sakis
sakis,
there`s some talk about bothersome oscillations here...
there`s some talk about bothersome oscillations here...
I would not say so...you can make whatever fancy PCB layout, if you do not fix the phase errors...
thats ok
its ok my friend ....
allow me to work with more simple devices ....
i wish this thread ( and others ) could be "closed " by someone saying : AAAA YOU MISSED THIS CAPACITOR !!!!
so the poor guy just put the blody capacitor on ....amplifier working case closed
In some threads is very good to look cause various opinion and extensive theoreticall approach will actually provide knowledge to people like me that dont have enough ....
I ONLY THINK THAT SOME TIMES IS GETTING OUT OF HAND AND PEOPLE MISS THE OBVIOUS .....
that's me ...that's my opinion
in another thread just arround the corner people are having argument about how much class A or overbiased class AB is one amplifier .......unbelivable ....
its ok my friend ....
allow me to work with more simple devices ....
i wish this thread ( and others ) could be "closed " by someone saying : AAAA YOU MISSED THIS CAPACITOR !!!!
so the poor guy just put the blody capacitor on ....amplifier working case closed
In some threads is very good to look cause various opinion and extensive theoreticall approach will actually provide knowledge to people like me that dont have enough ....
I ONLY THINK THAT SOME TIMES IS GETTING OUT OF HAND AND PEOPLE MISS THE OBVIOUS .....
that's me ...that's my opinion
in another thread just arround the corner people are having argument about how much class A or overbiased class AB is one amplifier .......unbelivable ....
funny, i just read an article in EDN where this engineering intern made a substitution for a 30 year old part, and the circuit started oscillating at 1.8Ghz, a lot higher than the original device's Ft. well the new device had an Ft of 8Ghz, whilr th original device had an Ft of 1.2Ghz. the oscillation was so bad, they were picking up RF from the ground traces (actually that's not uncommon when you re-engineer a bipolar output stage to work with mosfets, the mosfets can work into the VHF region while the bipolars might be lucky to have an Ft of 5Mhz.)
btw, here's what the Burr-Brown logo should look like:
btw, here's what the Burr-Brown logo should look like:
Attachments
Re: thats ok
Thanks for the offer to help RSK, I appreciate it, but I would rather go for a discrete design this time, there aren't many parts I could reuse in the MOS125 anyway.
Thanks Mooly, looks like an interesting design, unfortunately my PSUs are a bit to high for it (+-50V DC)
I'm sure I'll build it in the near future anyway though...I'll have to find a use for my BUZ's (after all I did spend about $100 on them)
Yeah, it's definitely a fake, however at this point I'm not surprised anymore, thanks for looking that up.
In a way I don't mind that the solution wasn't that simple... I learned allot from reading the reply's and other threads on the forum.
What do you guys thing of
http://www.adam.com.au/cgpap/QuasiWeb/nmos350_500.htm
?
It would be perfect for the PSU's I have +-50VDC
Anyone know how the amp sounds? A rough idea of the TDH?
Thanks.
Tibi.
RSK said:
Thanks for the offer to help RSK, I appreciate it, but I would rather go for a discrete design this time, there aren't many parts I could reuse in the MOS125 anyway.
Mooly said:
Thanks Mooly, looks like an interesting design, unfortunately my PSUs are a bit to high for it (+-50V DC)
I'm sure I'll build it in the near future anyway though...I'll have to find a use for my BUZ's (after all I did spend about $100 on them)
unclejed613 said:
Yeah, it's definitely a fake, however at this point I'm not surprised anymore, thanks for looking that up.
sakis said:
In a way I don't mind that the solution wasn't that simple... I learned allot from reading the reply's and other threads on the forum.
What do you guys thing of
http://www.adam.com.au/cgpap/QuasiWeb/nmos350_500.htm
?
It would be perfect for the PSU's I have +-50VDC
Anyone know how the amp sounds? A rough idea of the TDH?
Thanks.
Tibi.
Tibi, that design uses n channel vertical devices. Your best option for your complementary laterals I would say is rod elliots p101 mosfet amp. Its very simple and sounds excellent according to those who have built it. I think Sakis could help you here with a board layout. How many pairs of buz do you have???
Rsk just out of curiosity, does the mos125 also have a high voltage gain output scheme like this one??
Rsk just out of curiosity, does the mos125 also have a high voltage gain output scheme like this one??
Lumba Ogir said:
Hello Lumba,
It's here,
http://www.diyaudio.com/forums/showthread.php?s=&threadid=132367&perpage=20&pagenumber=3
I knew my amp was good. Now I know why. It's Class A 😀
Hi Tibi,
I won't keep banging on about it, but if it's a star musical performer your after. Have a go ? 50 volt rails aren't such a problem. The design is super stable, the single ended input stage arrangement sees to that, not that that was why I used it, it sounds better, way better. It's easy to test and check along the way, you can run it up with no outputs connected to make sure it's all working correctly.
I know the amps abilities, I should have more confidence to shout about it.
I have heard nothing better, if I had I would want it 🙂 It has no problem driving my B&W 703's which have a 3 ohm minimum impedance.
For reproducing music in a domestic setting it's unbeatable.
🙂
I won't keep banging on about it, but if it's a star musical performer your after. Have a go ? 50 volt rails aren't such a problem. The design is super stable, the single ended input stage arrangement sees to that, not that that was why I used it, it sounds better, way better. It's easy to test and check along the way, you can run it up with no outputs connected to make sure it's all working correctly.
I know the amps abilities, I should have more confidence to shout about it.
I have heard nothing better, if I had I would want it 🙂 It has no problem driving my B&W 703's which have a 3 ohm minimum impedance.
For reproducing music in a domestic setting it's unbeatable.
🙂
p101 from esp
as given from rod is an excelent amplifier ....very very stable producing a lot of power and also has high rails ...
BUT !!! pcb of P101 is something that rod dont give for free and you have to buy it from him
to my opinion also in this amplifier pcb is critical , rod's pcb is working like hell and the only think you may do is to buy it there .
on the other hand rod's pcb is very cheap and afordable to anyone i presume .
ia m not trying to advertise for esp ..... but since rod gives all his work to diy community for free .....then it would be wise and fair that he makes some small profit from the pcb
if you go for P101 just built it as is ...dont change anything and will be just fine
on the other hand quasi's amps are easy to built pcb is vailable , alot of support in extensive threads and my opinion about the amp is like this :
---the amp is true
---doesnt promise miracle doesnt make miracle
---well designed
--- safe to use ( hardly ever problems with it
---produces alot of power but on the safe side
---simple designs easier to built
---not easy to be effected under strange conditions
finally even though i dont like quasi complementery designs since i am a coubist and i like everything symmetric i think its a very good amp
as given from rod is an excelent amplifier ....very very stable producing a lot of power and also has high rails ...
BUT !!! pcb of P101 is something that rod dont give for free and you have to buy it from him
to my opinion also in this amplifier pcb is critical , rod's pcb is working like hell and the only think you may do is to buy it there .
on the other hand rod's pcb is very cheap and afordable to anyone i presume .
ia m not trying to advertise for esp ..... but since rod gives all his work to diy community for free .....then it would be wise and fair that he makes some small profit from the pcb
if you go for P101 just built it as is ...dont change anything and will be just fine
on the other hand quasi's amps are easy to built pcb is vailable , alot of support in extensive threads and my opinion about the amp is like this :
---the amp is true
---doesnt promise miracle doesnt make miracle
---well designed
--- safe to use ( hardly ever problems with it
---produces alot of power but on the safe side
---simple designs easier to built
---not easy to be effected under strange conditions
finally even though i dont like quasi complementery designs since i am a coubist and i like everything symmetric i think its a very good amp
Re: p101 from esp
I realized that, I only considered the Nmos because the parts would be easy to obtain here.
I have 3 pairs of BUZ, (one pair just in case something goes wrong while testing)
Hi Mooly,
If 50 Volt rails are not a problem I'll give it a try.
Would any component values need to be changed to accommodate the slightly higher voltage?
Also, what kind of power output should I expect from a +-50V supply into 8 ohms? Could it drive a 4ohm load?
I read through the "Mooly Amp" thread and I haven't found a PCB that was confirmed to be working, do you happen to have one?
Hi sakis,
thanks for the info.
I'll probably go with Mooly's amp this time since I already have most of the components for it.
homemodder said:
I realized that, I only considered the Nmos because the parts would be easy to obtain here.
I have 3 pairs of BUZ, (one pair just in case something goes wrong while testing)
Mooly said:
Hi Mooly,
If 50 Volt rails are not a problem I'll give it a try.
Would any component values need to be changed to accommodate the slightly higher voltage?
Also, what kind of power output should I expect from a +-50V supply into 8 ohms? Could it drive a 4ohm load?
I read through the "Mooly Amp" thread and I haven't found a PCB that was confirmed to be working, do you happen to have one?
sakis said:
Hi sakis,
thanks for the info.
I'll probably go with Mooly's amp this time since I already have most of the components for it.
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