Is that true Mike?
How about posting it on your website. I would really like to give this amp a try.
Blessings, Terry
How about posting it on your website. I would really like to give this amp a try.
Blessings, Terry
Hi Terry,
Have you tried Mike's amp ?
Its very good sounding even with mosfets...
regards,
K a n w a r
Have you tried Mike's amp ?
Its very good sounding even with mosfets...
regards,
K a n w a r
Hi Terry,
it seems to me that you are thinking over much more than building. These PCB issues are completely minor, the result will depend on proper wiring, shielding, grounding much more than on PCB modification. Here is the field for DIY improvements and usually greatest pain of DIY constructions.
Pavel
it seems to me that you are thinking over much more than building. These PCB issues are completely minor, the result will depend on proper wiring, shielding, grounding much more than on PCB modification. Here is the field for DIY improvements and usually greatest pain of DIY constructions.
Pavel
still4given said:
Hi Terry, i can upload some files this evening, but new version is not fully tested yet...
Mike
PMA said:
Hi Pavel,
I am trying to think things over. I have built 5 amps in the past 6 months. I think I can take a few days and think about how to proceed with this one. 😀
If there is nothing wrong with the design, why is Mike working to improve it? I might as well wait and build the best design if I can. At least I'm staying on topic. 😀
Blessings, Terry
still4given said:
Because measurings showed that it can be improved... 😉 Does not mean that the older one is wrong.
Mike
MikeB said:
Hi Mike,
Please forgive me. I worded that poorly. I didn't mean to imply that there is something wrong but that maybe there is a better version on the horizon.
Blessings, Terry
still4given said:
Better is the enemy of good. I built the current versions on perf board. Sounds great.
Interestingly, after I built one channel, I was able to do a neater job the second time. However, the second amp has just a very slight turn on thump under certain conditions and has about 5mv offset, as compared to the first, which has less than 2mv. I can tell no difference in sound. I think what Pavel and Mike are saying is that the layout differences between the two versions are likely to be overwhelmed by other choices, including components. Oh, and you'll still have a very fine amp.
Sheldon
So I'm totally new to DIYAudio, but I've been reading through this thread and I've got a wild hair to build this amp. But I have one newbie question. Having done a fair amount of soldering in my life, but never having etched a PCB, I'm thinking about having it done elsewhere. If I get rid of the top layer traces on MikeB's Eagle files for his first board, and add drill holes, is that file good to go?
Thanks.
Thanks.
Hi !
I've uploaded latest files for PCB:
Quasi Silk screen 80kb
File for print out (600dpi,zipped bitmap) 45kb
Eagle files 37kb
Don't forget, it's not fully tested, i just made one board and it worked fine...
The REs in input-LTP are reserved and can be skipped by 2 small wires. (just wanted to have the possibility,principally with 22ohms they enable to increase the 499ohm in feedback to 1k to lower gain, not tested yet)
matteson, i have no experience in getting pcbs produced, i always etched them. But your proposal sounds completely correct and should work.
Mike
I've uploaded latest files for PCB:
Quasi Silk screen 80kb
File for print out (600dpi,zipped bitmap) 45kb
Eagle files 37kb
Don't forget, it's not fully tested, i just made one board and it worked fine...
The REs in input-LTP are reserved and can be skipped by 2 small wires. (just wanted to have the possibility,principally with 22ohms they enable to increase the 499ohm in feedback to 1k to lower gain, not tested yet)
matteson, i have no experience in getting pcbs produced, i always etched them. But your proposal sounds completely correct and should work.
Mike
OK, I give up. what's the best way to get the bitmap to print the correct size?
Thanks, Terry
Thanks, Terry
Hello Terry,
i create for you a PDF with the PCB Image 600 Dpi.
See my symasym project page.
Download the PDF:
still4given said:
i create for you a PDF with the PCB Image 600 Dpi.
See my symasym project page.
Download the PDF:
An externally hosted image should be here but it was not working when we last tested it.
still4given said:
Every reasonable pictureviewer/editing program is able to print a picture with a given dpi. If you print the image with 600dpi it has exactly the size you need. Or you use the pdf from dx.master.
Mike
Can you give me a measurement from mounting hole to mounting hole so I can make sure it is printing the proper size? Every program I use to print it with gives me something different.
Thanks, Terry
Thanks, Terry
Terry,
maybe there is a problem with your printer drivers, rather than the file or the programs you use? Somtimes the printer drivers do not work well with certain programs. However, if you have problems with all programs, something is seriously wrong. Make sure to at least download the latest version of the printer drivers, to rule out that there is some bug they have fixed. Unfortunately, that won't rule out there is a bug they haven't fixed.
maybe there is a problem with your printer drivers, rather than the file or the programs you use? Somtimes the printer drivers do not work well with certain programs. However, if you have problems with all programs, something is seriously wrong. Make sure to at least download the latest version of the printer drivers, to rule out that there is some bug they have fixed. Unfortunately, that won't rule out there is a bug they haven't fixed.
Terry, Which programs are you using ?
ACDSee:
Go to print setup, here you can set resolution, should already be 600dpi. Set size to "default". and print.
Irfanview:
Click on "image information", there you can set dpi for image, then select "print" , and set "print size" to "Original size (from image DPI,no ratio)".
Photoshop:
simply print... (with 3.0, this version has no option to do it wrong)
The idea of dpi is to have exactly specified the resolution/size of printout. There is a slight mismatch because of printers accuracy, but the image must not be scaled, you will loose resolution.
The x-distance from hole to hole is 8.88cm or 3.5inch.
Mike
ACDSee:
Go to print setup, here you can set resolution, should already be 600dpi. Set size to "default". and print.
Irfanview:
Click on "image information", there you can set dpi for image, then select "print" , and set "print size" to "Original size (from image DPI,no ratio)".
Photoshop:
simply print... (with 3.0, this version has no option to do it wrong)
The idea of dpi is to have exactly specified the resolution/size of printout. There is a slight mismatch because of printers accuracy, but the image must not be scaled, you will loose resolution.
The x-distance from hole to hole is 8.88cm or 3.5inch.
Mike
Well, on my laptop here at work, I only have Adobe Photoshop Album 2 and it does not print the proper size. Hole to hole is 11.8cm. Microsoft photo editor soes not give me the option of actual size.
I pasted it into Word and that is about right. I'll use that. My computer at home will print the right size but I don't have a Laser printer there.
Thanks for your help.
Blessings, Terry
I pasted it into Word and that is about right. I'll use that. My computer at home will print the right size but I don't have a Laser printer there.
Thanks for your help.
Blessings, Terry