Ostripper,
Putting the noise of critics aside ...
I for one am very interested in seeing what you come up with. The more that I learn, the more I realize that I need (want??) to learn. Please push ahead. We are paying attention. It's good to have you back!
Putting the noise of critics aside ...
I for one am very interested in seeing what you come up with. The more that I learn, the more I realize that I need (want??) to learn. Please push ahead. We are paying attention. It's good to have you back!
Would you like to prove VFA is better for audio because it simms better? Which schematic to recommend to someone if all sounds the same? What's the point of hundreds schematics?
Teaching, learning, sharing, building, enjoying, understanding, and being comfortable while doing so without having to worry about what others think😉
Red wines all taste the same to some. But ,others would pay a hefty price
for a bottle of vintage.
Everybody has a favorite . Some can actually hear a difference.
Depending on their abilities , they might be right .... or they could just
be prejudiced by subconscience preferences.
Just give them the best designs , VFA or CFA. 🙂
OS
No need to wait. There is a thread for the purpose >HERE<. I don't have every version on hand at this moment but what is available is listed. Feel free to let me know if I can help you.
Has anyone ever used Alfet laterals? They don't seem to mind charging money for them but they look like they will plug right into a Slewmonster board.
http://products.semelab-tt.com/pdf/magnatec/ALF16N16W ALF16N20W.pdf
http://products.semelab-tt.com/pdf/magnatec/ALF16N16W ALF16N20W.pdf
I don't think it would be a huge problem to lay out a board to work with them. I have no idea what it would take for modifications to the drivers and bias circuits though. I'm thinking it would involve removing/bypassing the drivers and removing the thermal link for the bias transistors.
Laterals need the drain and source connections reversed for starters. Generally they don't require nor benefit source resistors, but Vgs matching is pretty much required for multiple pairs in parallel. Biasing is a little easier if you run them at about 100mA per pair to get them near their zero temperature coefficient. The gate capacitances are substantial, so an EF buffer (driver) would still be advised to keep the IPS happy.
Some others have asked about it but I don't think too many would build it due to the cost and generally poorer availability of the parts. Maybe I'd be wrong?
Some others have asked about it but I don't think too many would build it due to the cost and generally poorer availability of the parts. Maybe I'd be wrong?
Hello
These the circuit I would love to get some help.
Do I need those capacitors next to the mosfets 22uF.
Do I need both 1K resistor R114 & R115
I have questions like that.
Also if we can do any improvement, or any advise welcome and highly appreciated.
Now if these circuit bad place or bad time to post here please delete it, I will not get upset.🙂
Really I do not want to pollute these tread.
I didn't wanted to start a new tread for these.
Greetings gabor
These the circuit I would love to get some help.
Do I need those capacitors next to the mosfets 22uF.
Do I need both 1K resistor R114 & R115
I have questions like that.
Also if we can do any improvement, or any advise welcome and highly appreciated.
Now if these circuit bad place or bad time to post here please delete it, I will not get upset.🙂
Really I do not want to pollute these tread.
I didn't wanted to start a new tread for these.
Greetings gabor
Attachments
I think the laterals would go good with some of Valery's tube input designs. A fet that's designed for audio just sounds like a good idea. Too bad they're so hard to find. I'm thinking about laying out a board for this myself. Shouldn't be too hard to plagiarize one of your designs. Not needing source resistors actually makes it easier.
The devices you want to use are vertical MOSFETs that just happen to have a relatively low threshold voltage. The only thing that would need some adjustment would be the biasing arrangement. The values used with the IRFPs will way over-bias your devices. I'd start off with the standard values used for the BJT version.
R114 R115 can be a single 470R (that is install one or the other, on the OPS boards one location is actually for a capacitor). Do use the small capacitors at the drain connections.
I'm back on the layout side again.
As far as either the lateral/vertical devices ... it would be good to include
zener protection across G-D. Some laterals have these internally.
I am very satisfied with my new NAD CFA.
The finalized schema is (below).
I have some new component ideas (parallel CFB resistors) and
a newer more compact layout style ... 76 x 76mm is quite possible here.
-12 Q
-26 R (just 1 trimmer) no precision adjustment needed.
-14 C
-10 D
- 1 IC
- 63 parts total , not too scary (medium complexity).
The amp is the BEST 😀 in general . Best clipper , best offset , best
thermally. Also , best SLEW 😀 I did get 1K/uS with more CF applied.
All this is the direct result of the "NEW" VAS.
PS - As I said ... A CFA with VFA precision.
OS
As far as either the lateral/vertical devices ... it would be good to include
zener protection across G-D. Some laterals have these internally.
I am very satisfied with my new NAD CFA.
The finalized schema is (below).
I have some new component ideas (parallel CFB resistors) and
a newer more compact layout style ... 76 x 76mm is quite possible here.
-12 Q
-26 R (just 1 trimmer) no precision adjustment needed.
-14 C
-10 D
- 1 IC
- 63 parts total , not too scary (medium complexity).
The amp is the BEST 😀 in general . Best clipper , best offset , best
thermally. Also , best SLEW 😀 I did get 1K/uS with more CF applied.
All this is the direct result of the "NEW" VAS.
PS - As I said ... A CFA with VFA precision.
OS
