200w to 800w or am i missing something?

[djmarvellous]

Thanks andrew for the Reply

I was looking into modding this amp as to gain some knowlage
of how amplifier work and since a couple of my friends
own similar amplifiers it would be of much advantage.

wich design would you recomend I build for use with Lateral Mosfets?

Thanks in Advance

 

[AndrewT]

have a look at ESP's version.

There are many others.

 

[djmarvellous]

Sadly ESP101 does not have resistor values🙁

any other designs you could recomend?

 

[richie00boy]

If you buy the very reasonably priced board from ESP you get full build guide including part values.

 

[djmarvellous]

Sadly I dont have a credit card
and the US$ are 9.5 to 1
not to mention the shipping
so for me sadly that a bit on the expensive side

$22 & shipping $10 = $32
+- R320 for me here in South Africa

but thanks for the reply thou much apreciated

how about
http://users.swing.be/edwinpaij/ampli_mosfet_simple.htm
any others you can recomend?

 

[Nordic]

Your exchange rate is a little out... the dollar has been takeing a beating... its more like R6.50 to the dollar. Google converts $32 as R209 at the moment.

If you want it, and want to make a deposit in my account let me know and I will get it from Rod Elliot for you.

 

[richie00boy]

You can use other payment methods besides credit card.

 

[djmarvellous]

Thanks Nodic will get intouch with You.😎

anybody want to recomend other amps I can have a Look at?..

 

[east electronics]

not legend ....

it seems to me that amplifier you need is a DJ amp or for small pa application

so here are the rules ......

keep away from small mosfet amps promising 150-200w they may reproduce it on bench but bench tests is not PA application....PA use or abuse !!!!!

focus more on bjt amps they last longer and handle more abuse

if your application is small PA application it is wise to buy a ready made chinese amplifier that will perform your power requirments but may be not the quality ..... but thats not really importand is it ????

then construction of any legend amplifier for example for home use in low power and voltage will be a joy and will teach a lot about constructing but also quality .......

trying to mod a legend or esp 101 or others from audiophile amps to pa amps is never going to work properly .....belive me i tell this from a lot of expirience

still all i know about legend i can give to you and all my help with it as long as dr bora doesnt mind

best regards sakis

 

[djmarvellous]

I would Greatly Apreciate That

Wich BJT Amp would you recomend?

Thanx

 

[east electronics]

for pa.....

dont condstruct .....just buy any !!!! will do !!!

get a crown get a behringer get limit or gemini or qsc all these amps produce huge pa power and some of them very good quality for the money tou pay

for your monitors at home i will guide you to make a wonderfull legend with sweet and amazing sonics as our friend carlos destroyer x say ....even better !!!! for you home use a dx amplifier designed from carlos ...it will play like hell !!!!! power is good and sound is perfect

regards sakis

 

[djmarvellous]

I would greatly apreciate that
Patientle Waiting....

Thanks in Advance

 

[east electronics]

there you go

original schematic of legend 4 from dr bora and pcb lay out

this is exact copy of what dr bora gave me

 

[east electronics]

and schematic

to start with ......

 

[djmarvellous]

Do you perhaps have the copy that does not
have the components so I could use it to make a Board?

any modifications you would advise?...

Thanks in Advance

 

[east electronics]

MY MISTAKE SORRY

yes i can tell you a few things but just a litl bit later on in the day cause right now i am kind of busy

 

[djmarvellous]

Thanks Sakis😎

Greatly Apreciated.......

 

[east electronics]

just a few things

for starts

A)bc 550 will not work if your rails are above 40 volts you will have to replace them with 2n5401 ( keep in mind that pins ar totally oposite !!!!!!)

B) vas amplifier ..... can be also done with mje 340 but !!!!! if you mount a small heatsink to it ( not needed if rails are 40 volts ) DO NOT !!!! use a screw to attach it in the board eventhough existing hall on the pcb ....the screw it shelf creates capacitance and this is danger to ocilation ..... can use a plastic screw or a hetasink standing up together with vas transistor

C) in original pcb there no drilling to put the source resistors they have to be there to balance the current that flows between mosfets ....these resistors to my opinion have to there ...have to exist especially if you use rails above 40 volts but if you use rails of 40 volts ..... a good matching of the mosfets will not need source resistors .....

D) a legend of this comunity mr NELSON PASS looked at it and sugested that some capacitor should be placed inth ltp stage on minus side .... IE just right after 10R resistor that feeds the vas mje 340 to ground to make more clean and stabilized power to the ltp ( something like that was note yet tested )

E ) finally capacitor of some pico 20-80 should be placed B-C of vas amplifier to avoid ocilation .......

F) zenner diodes are often used in such a design between gates to avoid overdrive of mosfets .... in high rail voltage like 65 volts amplifier becomes unstable ( eventhough producing clean 200w almost !!!!!) so amplifier will fale no matter if zenner diodes are added or not

still nothing of these looks needed if your rails do not exceed 40+40 volts

truth !!!!! the amp in voltage like 40 volts is very musical with very clean high controlable midle and rich tight bass ..... to me a very nice amp for most kinds of music

knock your shelf out and have fun !!!!!

best regards sakis

 

[east electronics]

here is a pic

 

[AndrewT]

Hi Sakis,
the schematic shows resistors in the source leads of the upper bank.
But they have been moved to the drains in the lower bank.

Are these the resistors that the PCB needs to be re-drilled and located properly?


DJ,
Looking at some of the details in the Legend schematic, I cannot recommend this circuit.