Power amp under development

[sandeep kayarkar]

sir, i try what u told me last time but still its sounds like walkman using on 10'' woofer on full vol.

 

[sdman]

PC Boards?

Anyone selling selling PC boards for this amp?


Sam

 

[GodSaveMetal]

Hi greetings QUASI

what happened with NMOS MKII under development ?

Do you have finished final design with symmetrical clipping included cascoded second stage ?


I have build NMOS MKII under development and it works fine,... but have replace string of 3 1n4148 with 1 Amber LED


regards

I´m from PERÚ, and incredible more than 370 pages wow!!! it is my interest of this amplo!! my mail is rbarriost@yahoo.com,: please I wana you last develope amplo; NMOS MKII ; fully esplantion please , this is a great JOB!! congrats

 

[NMOS]

Anyone selling selling PC boards for this amp?


Sam

Yes i have PC Boards

 

[butch_vlad]

Hi HMOS,
Can you post image with the boards you have?
How much for 2 boards shipped to london?

Cheers
Vlad

 

[NMOS]

Hi HMOS,
Can you post image with the boards you have?
How much for 2 boards shipped to london?

Cheers
Vlad

Im sorry, I was a nice time but I do not longer build and support NMOS Amp

because

I habe now very much better sounding quasicomplementary BJT Design including all protections and relay free turn on delay, this design beat NMOS Amp,

its much clearer very transparent with imaging and depth so vivid you can “see” into the actual sound track. You’re going to hear every inner detail of the music the way the producer intended it to be heard and will playback any style of music in a Flawless manor.

I will share with Diy

 

[butch_vlad]

Ok, thanks.

 

[ibanezbass]

So will the Nmos series serve PA audio applications?(I mean would this power amp be a good choice for amplifying vocals or musical instruments during live performance?)

Thanks in advance

 

[mimura]

hi qsa.

please send me the latest nmos pcb desin ,control board and smps

v-vvv@hotmail.com

thanks

 

[Jansaen]

use this files
remember if you use press and peel method first file is ok but if you use some other method you might need to mirror the file

Thanks alot Mr.maxente

 

[wattaniya]

Im sorry, I was a nice time but I do not longer build and support NMOS Amp

because

I habe now very much better sounding quasicomplementary BJT Design including all protections and relay free turn on delay, this design beat NMOS Amp,

its much clearer very transparent with imaging and depth so vivid you can “see” into the actual sound track. You’re going to hear every inner detail of the music the way the producer intended it to be heard and will playback any style of music in a Flawless manor.

I will share with Diy

can u upload a image of this amp

 

[Kapkan]

NMOS200

Hi, everybody.

Prompt please: what standing current at NMOS200?

And that I bring together the amplifier, I do not know what current to expose.

Whether also it is possible to use condensers to 1000 pF on tension of 50 volts in case of a power +-35 volts? Or it is not enough?

PS If not so expressed I am sorry, I from Russia, know English badly, I use the translator.
PSS Yet up to the end completed, I look for angular heat sinks.

 

[SaMaHa]

You should read this:
????????? ?? Mosfet ? ???????? ???????? ?? ?? ?????? ???????????????? - ????? ?? ????????????????
Chuvak, idi a vegalab ili na cxem.net

 

[pinkmouse]

I know you can't do anything about the link, but could you please post the rest in English. Thanks.

 

[SaMaHa]

I know you can't do anything about the link, but could you please post the rest in English. Thanks.

No problem.

Prompt please: what standing current at NMOS200?

Constant current is about of 30 mA.

Whether also it is possible to use condensers to 1000 pF...

Yes it is.

 

[Kapkan]

SaMaHa
Спасибо за ссылки, нашел ответы на все вопросы.
Лучше на радиокот, cxem.net не очень нравится.
(Thanks for the link, found the answers to all questions.
It is better to radiokot, cxem.net do not really like.)

 

[Kapkan]

Update:
SaMaHa , thank you.

 

[john78]

Biasing amp

I am building the Quasi NMOS 500. I used .15 ohm resistors instead of the .47 ohm Quasi used as emitter resistors. In the construction guide Quasi states that the amp should be biased to 30 ma per output transistor.
5. If everything seems ok adjust VR2 to set the output stage bias current, by measuring the
voltage across the positive rail resistor. Adjust for a reading of 3 volts per output FET pair. I.e.
For a 6 FET board set for a voltage of 9 volts. This equates to a bias current of 30mA per
FET pair or 90 mA total. For a 10 FET board set for a voltage of 15 volts.
6. If everything seems ok, check the output offset voltage and adjust VR1 to achieve an offset of
less than 10 mV.
7. All being well switch off, back off the bias control trimmer (VR2) and replace the 100 ohm
resistors with 10 ohm 1 watt resistors. Switch on again and re-adjust VR2 to get 0.3 volts per
per FET pair across the positive rail 10 ohm resistor.

Is this final setup still correct even though I used .15 ohm resistors instead of the .47 ohm Quasi used?

 

[AndrewT]

Try using the same Vre value, i.e. 30mA across 0r47 = 14mVre
Using this value of Vre will result in ~100mA of output bias current per output pair.

This may be too much both for heat dissipation and to minimise crossover distortion, but it is a starting point to work from.

 

[engel dela pena]

is there anyone out there try using ferrite beads at fets gate?
how to implement this which is directly connected to fets gate,is it the ferrite or gate resistor?