Nice work, Marc!
For 1.5uH with 1.2mm wire, you'd need 5mm former and about 25 turns.
But for this amp it's not critical at all, it's very stable.
Hugh
For 1.5uH with 1.2mm wire, you'd need 5mm former and about 25 turns.
But for this amp it's not critical at all, it's very stable.
Hugh
Idefixes,
Your build is coming along nicely!
What chassis and heat sinks do you in mind for this project?
Your build is coming along nicely!
What chassis and heat sinks do you in mind for this project?
For the Heatsink i posted a picture here : https://www.diyaudio.com/forums/solid-state/255427-simple-quasi-complimentary-mosfet-amplifier-249.html#post6738650
They mesure 230x195x40mm with a base of 10mm thickness.
I plane a monobloc configuration with 2 independant chassis made MDF that i will paint in glossy white. One mono bloc will mesure 240x240mm front and 260mm deep. Each heatsink will take place in the middle of the case and will shown only is uper face. I think i will begin case building this weekend
Marc
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Hello ideafixes
greetings i have been wanting to make this amplifier on your pcb i
see a 2200uf 6.3 volt cap but in the schematic there is no such value cap
please can you help.
warm regard
Andrew
greetings i have been wanting to make this amplifier on your pcb i
see a 2200uf 6.3 volt cap but in the schematic there is no such value cap
please can you help.
warm regard
Andrew
Hi Andrew,
i have a bunch of these cap in stock from VSSA project. It's C4 in schematic. In the thread you will find value from 100 to 2200uf for these. I have these fine gold in stock so wanted to give them a try.
Marc
i have a bunch of these cap in stock from VSSA project. It's C4 in schematic. In the thread you will find value from 100 to 2200uf for these. I have these fine gold in stock so wanted to give them a try.
Marc
Hello
Idefixes
greetings and many thanks for your guidance today i will try to make
PCB for this amplifier i will be using IRF4668 will it be a problem .
warm regards
Andrew.
Idefixes
greetings and many thanks for your guidance today i will try to make
PCB for this amplifier i will be using IRF4668 will it be a problem .
warm regards
Andrew.
IRF4668
Hi Andrew,
This is a 520W 200V 130A hexfet with a Ciss of 10.7nF.
In this role it's too much, the gate drive is too heavy.
I would suggest a mosfets with around 280W 150V 40A.
This would have a Ciss of around half, easier to drive.
It would work, but be limited for slew and HF.
Hugh
Hi Andrew,
This is a 520W 200V 130A hexfet with a Ciss of 10.7nF.
In this role it's too much, the gate drive is too heavy.
I would suggest a mosfets with around 280W 150V 40A.
This would have a Ciss of around half, easier to drive.
It would work, but be limited for slew and HF.
Hugh
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Hello Aksa
greetings and thank you for the mosfet advice i will use IRF240
what is the correct method to set up this amplifier.
warm regards
Andrew
greetings and thank you for the mosfet advice i will use IRF240
what is the correct method to set up this amplifier.
warm regards
Andrew
Runs best at a quiescent of 125ma.
Read through the thread and focus on construction.
Which pcb will you use?
HD
Read through the thread and focus on construction.
Which pcb will you use?
HD
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Hello
greetings and many many THANKS to Ranchu Aksa and Ideafixes for this
wonderfull sweet sounding amplifier.
warm regards
Andrew
greetings and many many THANKS to Ranchu Aksa and Ideafixes for this
wonderfull sweet sounding amplifier.
warm regards
Andrew
Wonderful news, Andrew!
The quasi is a very strange beast with its npn bipolar and nmos output stage. It looks quite weird, but it works very well and offers quite a bit of second harmonic which many really like - like a tube.
This was a wonderful thread too, with five of the pcbs offered. My favourites were Phunk's organic pcb, and Thiago's integrated amp with independent power supplies. A terrific amp project indeed.......
Ciao,
Hugh
The quasi is a very strange beast with its npn bipolar and nmos output stage. It looks quite weird, but it works very well and offers quite a bit of second harmonic which many really like - like a tube.
This was a wonderful thread too, with five of the pcbs offered. My favourites were Phunk's organic pcb, and Thiago's integrated amp with independent power supplies. A terrific amp project indeed.......
Ciao,
Hugh
Hello Aksa
greetings thank you i saw Phunks PCB design yes truly work of art
i shall get the pcb made at JLC. Just want to ask you if 2 volt RMS
input signal from my dac player is ok.
warm regards
Andrew
greetings thank you i saw Phunks PCB design yes truly work of art
i shall get the pcb made at JLC. Just want to ask you if 2 volt RMS
input signal from my dac player is ok.
warm regards
Andrew
Hi AVT,
I noted you live in SA - I went to school there and have happy memories.
How does the quasi sound compared with your impressive stable of amps?
Some said it was not particularly resolving, but I have always found surgical resolution to be overstated - it can be fatigueing.
Hugh
I noted you live in SA - I went to school there and have happy memories.
How does the quasi sound compared with your impressive stable of amps?
Some said it was not particularly resolving, but I have always found surgical resolution to be overstated - it can be fatigueing.
Hugh