That is why I thought we would end up with a CFA design here and not end up back at the VFA designs. So many say the sound of the CFA is the superior sound baring the lower distortion numbers of the VFA's. I made friends with Esperando very early on this website. He is a true believer in the CFA's superior sound after a long time as a designer and recording engineer.
My specialty has been waveguides for a long time. Patented waveguide design when I was 21 and that was a long time ago.
My specialty has been waveguides for a long time. Patented waveguide design when I was 21 and that was a long time ago.
OS, I know you can do it.
SMD resistor dan capacitor can find easily in my country, but SMD transistor is hard to find. You can use SMD resistor and capacitor if necessary.
This is the "rumble" .... we have 2 excellent CFA IPS's (NAD-H + CFA-X) 😕 .
I am a "design mill" , why not pop out a few VFA's as well ?
The leach based amp seems to match the best CFA's in
the slew category.
I would say the "Ultimate rumble" would be "spooky" and the
NAD ... both exhibit 200V/us slew capability one is VFA , the other
CFA.
Once you have the OPS built ... decide on a front end.
More will come and build , once any "bugs" are ironed out ...
listening impressions are determined , the winners can be
integrated into complete boards.
It is better to prototype first ... no dissatisfaction later .
I have seen too many buggy designs here lately in the forum ...
I at least want to match or exceed the success level of DIYA's
"Badger" project.
OS
OS,
I guess I can look for a prototype board house to make a few boards. I don't know how to do the Gerber's for the boards so that will be another thing. Bimo sent me a board supplier but I had trouble with there website, probably my slow DSL connection, but that is overseas. So many choices here and a lot to comprehend.
I guess I can look for a prototype board house to make a few boards. I don't know how to do the Gerber's for the boards so that will be another thing. Bimo sent me a board supplier but I had trouble with there website, probably my slow DSL connection, but that is overseas. So many choices here and a lot to comprehend.
Did you see member maouna's PCB (nearly board house Q) ?
He used toner transfer .. it is sooooo easy.
Even dummy, hardheaded me got it right the first (uhhh , second time).
I did make all these designs single layer , toner transfer ready.
OS
Hey OS, if you want to i can add your links to your first post together with attachments, instead of just links....
OS,
I didn't see the comment on the boards until this morning, I just assumed that you actually sleep at some point! Seems I would have to get the blank boards and chemistry which I was watching earlier and how the chemistry sounded somewhat nasty? I also noticed you guys needed specific HP printers, I have a multicolor Epson photo printer so I assume you would need a laser printer? There is a Fry's where they have all the supplies but I have never paid much attention to anything there except the breadboards, and these days it is all Arduino stuff. I was looking at a bunch of prototype board houses that make anywhere from one board on up, most want a minimum of 10 boards or so. I started life working in a medical lab so I am not afraid of chemistry but do have a good respect for working with chemicals. Polyurethanes are one of my specialties so what you are doing is probably less toxic than what I have worked with for years. I guess I would have to check on the printer, I assume you are using a laser printer if you are talking toner temps, my ink jet isn't going to do that.
I didn't see the comment on the boards until this morning, I just assumed that you actually sleep at some point! Seems I would have to get the blank boards and chemistry which I was watching earlier and how the chemistry sounded somewhat nasty? I also noticed you guys needed specific HP printers, I have a multicolor Epson photo printer so I assume you would need a laser printer? There is a Fry's where they have all the supplies but I have never paid much attention to anything there except the breadboards, and these days it is all Arduino stuff. I was looking at a bunch of prototype board houses that make anywhere from one board on up, most want a minimum of 10 boards or so. I started life working in a medical lab so I am not afraid of chemistry but do have a good respect for working with chemicals. Polyurethanes are one of my specialties so what you are doing is probably less toxic than what I have worked with for years. I guess I would have to check on the printer, I assume you are using a laser printer if you are talking toner temps, my ink jet isn't going to do that.
To Thimios. you mean for the output stage? i used mje340-350 for predrivers,mje15032-33 for drivers and mjl21193-4 for output. for thermal compensating and cap multiplier transistors ,ostripper suggests mje340-350 as well but there are many alternatives.
It would be better to answer himself for the alternatives we can use.
buzzford,
That is more than appreciated. I would be looking at his 5 pairs ops section though I am only going to use a max of three pairs in my initial design and the NAD input stage. As long as OS doesn't think he is going to make any more changes! Or someone finds something that needs to be changed? This has been a wild ride for sure from how this thread started.
Steven
That is more than appreciated. I would be looking at his 5 pairs ops section though I am only going to use a max of three pairs in my initial design and the NAD input stage. As long as OS doesn't think he is going to make any more changes! Or someone finds something that needs to be changed? This has been a wild ride for sure from how this thread started.
Steven
No i mean input transistors .
Have you used these a992 e.t.c or you have used bc... series?
Spooky has finished the "hairpulling" layout stage ......😱😱😱 .
What a PITA !!! 🙁
Should of known what I was getting into when I added a Servo ,
2 CCS's , and a Hawksford cascode to a basic Leach ....
It looks good ... (below) NFB is isolated ... a little extra room for
an alien or ghost graphic. REALLY have to check it out (errors !)
11 jumpers , 50 passives , 25 semi's , and one evil chip. whoa !
OS
Attachments
Are you done now OS! Seems like enough versions to get to the answer of which implementation will sound the best or at least a bunch of great sounding amps. Perhaps we need to put up one of those weird number and letter things to see if you are human or just a mad robot designer! 😀
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Just one more ... the "symasui" , I will share it ... but it is for my 10"
sub. Will design and build an active X-over for it.
I must build it ... it is a close design to my 32 year old Sansui triple EF
receiver (Z3900) ... that I found in a dumpster.
PS - I'm labeling the "spooky" Leach now ... The Leach topology is VERY
popular with hobbyists . (wait til' they get a load of this one... JOKER) 😀
OS
Thanks OS. Make that active filter a 4th order with some simple op amps such as the 5532 and it will be a nice addition to the rest of this. Saleen Key type filters or a simple LR would be appreciated. I have the D. Self active xo book, a great source of information.
Help me on this one ...
The 21'st century "Leach" is done. It should smoke the HK990 , as
the 990 has NO cap multipiers (better psrr here). The HK DOES have 2Q
CCS's ... so we might be pretty close to this 2500$ amp.
Below is the finished (red version) ... and the rails colored (red/blue/ green )
...standard V+/V-/0V colors.
I posted the schema that I derived this "monstrosity" from ...as the (middle)
attachment.
.ASC is also posted ... this thing "smokes" 😱 .
PS - R10/19 are the "fine tune" for CCS/ IP currents , use 33-82R here...
(saves space and 6$ for trimmers) cheep ...
OS
The 21'st century "Leach" is done. It should smoke the HK990 , as
the 990 has NO cap multipiers (better psrr here). The HK DOES have 2Q
CCS's ... so we might be pretty close to this 2500$ amp.
Below is the finished (red version) ... and the rails colored (red/blue/ green )
...standard V+/V-/0V colors.
I posted the schema that I derived this "monstrosity" from ...as the (middle)
attachment.
.ASC is also posted ... this thing "smokes" 😱 .
PS - R10/19 are the "fine tune" for CCS/ IP currents , use 33-82R here...
(saves space and 6$ for trimmers) cheep ...
OS
Attachments
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