Nelson Pass said:Commenting on the particular mis-match of the complementary
types, notice that the distortion is primarily second harmonic
on the amplifier and that the distortion vs power curve looks
just like a classic single-ended amp.
This imparts a particular sonic signature different from the
usual push-pull arrangement where the character is 3rd harmonic.
Thanks, I will go with mismatchd stones as I have had experience
of it with Zen V5. I will re-fill F1 having a bit higher rail voltages.
I would try to adjust R values, if necessary. I might be able to
manage this within few days when I get jfets, not using PCBs, but
applying P2P as usual. ~ ^^
If I prefer more second harmonic, should I use higher mismatches device between PMOS and NMOS?
Mr. Pass, may I know why you prefer to use TL431 in place of the usual Vgs multiplier, which is more common in the push-pull stage with the added benefit of temperature feedback? How does F4 overcome the temperature instability?
I've just completed F2 and SL10. It just sound marvelous driving my Coral Flat 8A and now I'm addicted to build the F4. Thanks a lot Mr. Pass.
First Watt Preference
Aha! Down to the meat of it all. There is no right answer, and it is part dependent on your taste, part on your music, and your source.
The F1 is super clean and dynamic. If your source is lean, your music will be lean. If your source is rich, your music will be rich. It is the real truth machine, with nothing taken out and nothing added. Ruthlessly revealing.
The F2 adds some 2nd harmonic to this. On lean source material this sounds better than the F1. It is putting a little color in your music, and on dry material it is a pleasant addition. Some like that additional color, some do not. Your choice.
The F3 sounds has a very light touch of sweetness. Sounds more like a great tube amp than any solid state amp I have heard, except that it has the same basic tonal characteristics from highs to lows - something most tube amps dream about.
The F4 sounds like a cross between the F1 and the F3. Cleaner than the F2, a touch of sweetness, but the truth is still front and center. I have not heard this amp in my system (yet), so my thoughts about this may change. It is a very exciting product.
Nelson, with his greater experience, may be better able to describe all of these amps. But as to which is best? That is like saying vanilla is better than strawberry - it is a matter of what you enjoy. All of these bring something different to the table.
Not sure if that helps, but it is the best I can do.
Aha! Down to the meat of it all. There is no right answer, and it is part dependent on your taste, part on your music, and your source.
The F1 is super clean and dynamic. If your source is lean, your music will be lean. If your source is rich, your music will be rich. It is the real truth machine, with nothing taken out and nothing added. Ruthlessly revealing.
The F2 adds some 2nd harmonic to this. On lean source material this sounds better than the F1. It is putting a little color in your music, and on dry material it is a pleasant addition. Some like that additional color, some do not. Your choice.
The F3 sounds has a very light touch of sweetness. Sounds more like a great tube amp than any solid state amp I have heard, except that it has the same basic tonal characteristics from highs to lows - something most tube amps dream about.
The F4 sounds like a cross between the F1 and the F3. Cleaner than the F2, a touch of sweetness, but the truth is still front and center. I have not heard this amp in my system (yet), so my thoughts about this may change. It is a very exciting product.
Nelson, with his greater experience, may be better able to describe all of these amps. But as to which is best? That is like saying vanilla is better than strawberry - it is a matter of what you enjoy. All of these bring something different to the table.
Not sure if that helps, but it is the best I can do.
Re: First Watt Preference
Uhm....Being just a follower, it shuold be cleaner than the F2. Jfet input brings a touch of sweetness, mismatched output devices bring some 2nd order harmonic, so it sounds a bit like single-ended....
Not having input Jfets at the moment, I was thinging about ways to make a simple buffer with irf610/irf9610 or similar, but..than it may loose a bit of sweetness. Using matched ouput devices should make it a bit more "clear" while unmatched provide more"romantic" sound?
Have I gone too far?
Jon Ver Halen said:
Uhm....Being just a follower, it shuold be cleaner than the F2. Jfet input brings a touch of sweetness, mismatched output devices bring some 2nd order harmonic, so it sounds a bit like single-ended....
Not having input Jfets at the moment, I was thinging about ways to make a simple buffer with irf610/irf9610 or similar, but..than it may loose a bit of sweetness. Using matched ouput devices should make it a bit more "clear" while unmatched provide more"romantic" sound?
Have I gone too far?
bogdan_borko said:
Of course that is the DC value, but the JFETs are capable of
sourcing quite a bit more AC. How much do you think you need
here in order to sound good?
As to the matching thing, please note that the parallel devices
are matched - we have been referring to the (mis)match between
P and N types.
Sorry my mistake. Sometimes a man can`t see a tree even if it`s in from of him...
I`m working right now on my own design (voltage amplifier + current amplifier(follower) and I`m wondering wath is the best choise for voltage amplifier. I need 18V peak to peak and input impedance of follower is about 50K. I was experimenting in simulator with a one stage nfb single ended voltage amplifier with heavy local feedback working with +250V and results are very very good. I made it in practice and the sound is magnificent. The only "problem" is that is capacitor coupled.
I could post the schematic here if anyone interesed...
cheers!
I`m working right now on my own design (voltage amplifier + current amplifier(follower) and I`m wondering wath is the best choise for voltage amplifier. I need 18V peak to peak and input impedance of follower is about 50K. I was experimenting in simulator with a one stage nfb single ended voltage amplifier with heavy local feedback working with +250V and results are very very good. I made it in practice and the sound is magnificent. The only "problem" is that is capacitor coupled.
I could post the schematic here if anyone interesed...
cheers!
Hi , i like to make some mod on this amp ,will anyone like to help me ? i have a lot of amplifier transformer ( Marantz ,Hk pioneer) most of them have ~ 45-0-45 vdc @ 4A , can i use on F4 ? and i like to reduce the bias to class AB and use only 1 or 2 pair output mosfet . possible ?
btw ,to be honest , i like all the diy amp design by Mr Pass , but that kind of amplifier not practical , waste too much . (u can build it but u cannot enjoy it ) !!! and how many people on earth can afford big horn speaker ? i rather stick with Class AB and not all in this Class are rubbish .Some are better than Class A .
btw ,to be honest , i like all the diy amp design by Mr Pass , but that kind of amplifier not practical , waste too much . (u can build it but u cannot enjoy it ) !!! and how many people on earth can afford big horn speaker ? i rather stick with Class AB and not all in this Class are rubbish .Some are better than Class A .
TJ,
You are an old member, and have learned that most all amps on this side of the forum are class A. What you are proposing is a completely different animal and IMO not recommended.
On the Solid State forum you will find hundreds of nice class AB amps with those rail voltages, if I were you I would stick to those. No offence intended.
You are an old member, and have learned that most all amps on this side of the forum are class A. What you are proposing is a completely different animal and IMO not recommended.
On the Solid State forum you will find hundreds of nice class AB amps with those rail voltages, if I were you I would stick to those. No offence intended.
Babowana said:
There are many good speakers offering high efficiency.
Many music lovers like such speakers and want to drive them
with good amp.
Papa is offering us elegant amps free.
Why a devil should complain?
you are (same as really You are) right with these..........
but I can't to not see that you are grumpy lately?