Re: Transistor type?
Are you sure? Take a look at the attachement.
Farnell
http://uk.farnell.com/jsp/Semicondu...playProduct.jsp?sku=1211721&_requestid=205166
fab said:
Are you sure? Take a look at the attachement.
EWorkshop1708 said:
Farnell
http://uk.farnell.com/jsp/Semicondu...playProduct.jsp?sku=1211721&_requestid=205166
Attachments
Re: Re: Transistor type?
[
I was referring to static DC power dissipation....
Anyway, 150mw is not that high for a 500mW device...
but of course to be on the safe side I understand your selection.
Also, can you provide your opinion on using Lateral mosfets in place of the thermal track devices...
Thanks
[
roender said:
I was referring to static DC power dissipation....
Anyway, 150mw is not that high for a 500mW device...
but of course to be on the safe side I understand your selection.
Also, can you provide your opinion on using Lateral mosfets in place of the thermal track devices...
Thanks
Re: Re: Re: Transistor type?
How hot will it run?
What de-rating factor do you apply?
What is the peak operational current?
How close is that to the absolute max current?
dissipation of 150mW is high for a 500mW unsinked device.fab said:
How hot will it run?
What de-rating factor do you apply?
What is the peak operational current?
How close is that to the absolute max current?
Re: Re: Re: Re: Transistor type?
Andrew,
*150mw is max power dissipation as per Roender since static is about 75mw (2ma DC at 35vdc) ...
*500mw is for 25C ambient as per datasheet of BC550.
*peak operational current : 150mw at 35v gives 4ma
*Absolute max curent is 200ma as per datasheet
😉
AndrewT said:
Andrew,
*150mw is max power dissipation as per Roender since static is about 75mw (2ma DC at 35vdc) ...
*500mw is for 25C ambient as per datasheet of BC550.
*peak operational current : 150mw at 35v gives 4ma
*Absolute max curent is 200ma as per datasheet
😉
Fab,
Do not forget that output stage dissipation at idle is 37W per monoblock and PCB orientation expose components to heat.
For all active components we should derate power dissipation for 50-60grdC, to be on the safe side.
Regarding output stage with laterals, I have a very good experience with 2sk2221/2sj352 but not with this topology. I like very much how this mosfets sound on mids and treble but I don't like the bass response.
Mihai
Do not forget that output stage dissipation at idle is 37W per monoblock and PCB orientation expose components to heat.
For all active components we should derate power dissipation for 50-60grdC, to be on the safe side.
Regarding output stage with laterals, I have a very good experience with 2sk2221/2sj352 but not with this topology. I like very much how this mosfets sound on mids and treble but I don't like the bass response.
Mihai
Re: Re: Re: Re: Re: Transistor type?
Once you know that operational temperature you MUST de-rate the SOAR to account for this. I suspect you could be down to around 200 to 300mW. If your peak current is 4mA, then the max Vce <=75Vce
What if during some unforeseen/unmodelled condition the peak current goes to 5mA or 10mA?
Icmax=200mA has absolutely no bearing on this part of your design.
fab said:
you must find/calculate/measure the Tc of the devices if you decide to run them hot. If you run them cold this can be avoided.roender said:
Once you know that operational temperature you MUST de-rate the SOAR to account for this. I suspect you could be down to around 200 to 300mW. If your peak current is 4mA, then the max Vce <=75Vce
What if during some unforeseen/unmodelled condition the peak current goes to 5mA or 10mA?
Icmax=200mA has absolutely no bearing on this part of your design.
Laterals mosferts...
Thanks for your comments.
Regarding lateral mosfets sound with bass can you clarify why this particular topology is not suitable? Do you have a technical possible explanation or is it just your experience with resulting sound?
Thanks
roender said:
Thanks for your comments.
Regarding lateral mosfets sound with bass can you clarify why this particular topology is not suitable? Do you have a technical possible explanation or is it just your experience with resulting sound?
Thanks
Last night I've listened to JAZZ live recording made by VTL. It is glamorous, I can swear that Todd Cochran is singing in my living room.
http://www.gate.net/~vital/p61.htm
On minimal recordings made with one or two microphone and without mixing, you can fell the music, it has body and soul.
Guys, please make yourself a favor an build this amp. It is an ultimate experience if you like jazz and classical music.
Cheers
Mihai
http://www.gate.net/~vital/p61.htm
On minimal recordings made with one or two microphone and without mixing, you can fell the music, it has body and soul.
Guys, please make yourself a favor an build this amp. It is an ultimate experience if you like jazz and classical music.
Cheers
Mihai
After reading through the thread, I am very interested in building this design. Is there still a groupbuy being organized? If so, I'm definitely interested in a stereo set. It sounds like roender has done a nice job.
I've done some other projects (speakers, passive preamp, DAC), but I'm a newbie to amps. It's difficult to choose a first project. I'm also interested in a couple other well regarded designs (MikeB's symasym and Carlos' Precision). Whatever I end up building, I'll probably need some help along the way.
Regards,
Ted
I've done some other projects (speakers, passive preamp, DAC), but I'm a newbie to amps. It's difficult to choose a first project. I'm also interested in a couple other well regarded designs (MikeB's symasym and Carlos' Precision). Whatever I end up building, I'll probably need some help along the way.
Regards,
Ted
Mihai,
An incredible drummer on that recording, Clayton Cameron also played with Tony Bennett, if you ever get to see him live AMAZING brush work and technique!, a true smooth player with tricks up his sleeve.
Colin
An incredible drummer on that recording, Clayton Cameron also played with Tony Bennett, if you ever get to see him live AMAZING brush work and technique!, a true smooth player with tricks up his sleeve.
Colin
This amp is spectacular, no other words.
The bass control is incredible. I thing that this low output impedance with high current capacity make a real difference. My speakers never plays like this before. Deep super controlled extended bass.
The Mids are naturals , very good, like my Symasym.
The highs are like the low end, more extended, more present, very sweet.
This extended response seems to enlarge the presentation, big soundstage, very dynamic.
It's a fantastic amp, and the funny thing, the hotter it is , the better it play and the polarisation seems to stay at it's setting.
Roender , thank you very much for this amp. I think i will stick on this one, enough for me to.
I really encourage anyone who need a HI-FI amp to build it. It's not cheap for home cinema , but it's a real Hi-Fi amp.
And like Roender said it's a little triky to build, not a first time attempt.
My speakers are BW DM 603 S3.
The bass control is incredible. I thing that this low output impedance with high current capacity make a real difference. My speakers never plays like this before. Deep super controlled extended bass.
The Mids are naturals , very good, like my Symasym.
The highs are like the low end, more extended, more present, very sweet.
This extended response seems to enlarge the presentation, big soundstage, very dynamic.
It's a fantastic amp, and the funny thing, the hotter it is , the better it play and the polarisation seems to stay at it's setting.
Roender , thank you very much for this amp. I think i will stick on this one, enough for me to.
I really encourage anyone who need a HI-FI amp to build it. It's not cheap for home cinema , but it's a real Hi-Fi amp.
And like Roender said it's a little triky to build, not a first time attempt.
My speakers are BW DM 603 S3.
Thanks for the review DRZ1; you're making me jealous! My ultimate goal is to build a real Hi-Fi amp.
If you could bear with a newbie for a moment, can you explain which aspects of the build make it tricky? Is it the number of components and their layout on the board? Or is it the need to understand the circuit in order to verify and troubleshoot it? I'm just trying to get a feel for how far "over my head" I might get myself if I tried to build this.
If for instance, the trickiness is limited to parts count and stuffing the board correctly, I have some confidence that I could proceed, since my digital projects have been pretty complex, and have involved soldering surface mount devices. But if, as I suspect, there are subtle nuances to the design that might not be obvious, or require a better understanding to get right, then I might get in trouble. I'm also planning to build one of Carlo's amps, and that might be a better first-time project. But I'd still like to be in on a group buy for this board, to work on when I "graduate."
Ted
If you could bear with a newbie for a moment, can you explain which aspects of the build make it tricky? Is it the number of components and their layout on the board? Or is it the need to understand the circuit in order to verify and troubleshoot it? I'm just trying to get a feel for how far "over my head" I might get myself if I tried to build this.
If for instance, the trickiness is limited to parts count and stuffing the board correctly, I have some confidence that I could proceed, since my digital projects have been pretty complex, and have involved soldering surface mount devices. But if, as I suspect, there are subtle nuances to the design that might not be obvious, or require a better understanding to get right, then I might get in trouble. I'm also planning to build one of Carlo's amps, and that might be a better first-time project. But I'd still like to be in on a group buy for this board, to work on when I "graduate."
Ted
The difficulty is the matching of transistors , mainly output ones. It must be pretty tight i think.
But the other tasks are no problem at all for a guy that can do others common electronic tasks.
A group buy would be a must for a good PCB, and i'm considering if incorporation of the driver PS regulator would be good. It probably reduced thes cost of the PCBs.
i Have made some minor mod to the layout to accomodate components easily available in US or Canada.
Mihai can give a idea.
But the other tasks are no problem at all for a guy that can do others common electronic tasks.
A group buy would be a must for a good PCB, and i'm considering if incorporation of the driver PS regulator would be good. It probably reduced thes cost of the PCBs.
i Have made some minor mod to the layout to accomodate components easily available in US or Canada.
Mihai can give a idea.
DRZ1 said:
Thank you very much Denis
I am glad that you like my baby 😀
I'm sorry but I am in a hurry, between two trips, first on Paris and now I must go to TelAiv.
We will talk when I'll come back.
Cheers,
Mihai
Sorry for not sustaining this thread in the last weeks, I've been very busy lately.
Opinions from those who already build RMI-FC100?
Opinions from those who already build RMI-FC100?
I'm in the final steps of construction, need to add a slow start.
I have listened on smaller speakers with the same conclusion. Really good bass control, very good treble. It realy make a good difference.
When a compare with my others amp (symasym, old Luxman and my big Marantz7001) The sounstage is more realistic too. It's less in your face, all the soundstage seem to go back at a better place.
My friends like it two...two more FC100 are in started.I have job for couple of months..😀
I have listened on smaller speakers with the same conclusion. Really good bass control, very good treble. It realy make a good difference.
When a compare with my others amp (symasym, old Luxman and my big Marantz7001) The sounstage is more realistic too. It's less in your face, all the soundstage seem to go back at a better place.
My friends like it two...two more FC100 are in started.I have job for couple of months..😀