My_Ref Fremen Edition - Build thread and tutorial

Thank’s to the people writing from many years about Mauro Penasa my_ref amplfier i was encouraged to give new life to a old myref rev A,the original board of Mauro .
I did it just for play with a new toys ,discovering that my_ref isnt a toy amplifier
I have applied the evo A mods,add two big 25 volt 6 ampere surplus talema transformer,and and few better components in the crucial place

My original built of rev A many years ago was’nt so accurate..
It sound now very ,very good.
A lot of detail,armonious and fast
I think that the transformers help the amplifier to play very well at low mid frequency that are fast and articulate
It works with low frequency as 100 watt amplifier,very clean
Great work Tonix! I have same kind of enclosure to install my modules but i want to use also the inner chassis and i was thinking to install a 2mm thick copper plate between Lm3886 and aluminium laterals.
 
I still look at your builds with envy! Mine is still cabriolet, and ... playing in my "man cave" (the garage) with a pair Scythe Kro Craft. Sob!

BTW, I've still a Salas DCB1 around, slightly HotRodded, I'm thinking of cramming in the same box, to have some space - the original project, two house movings ago, were a pair of hifi2000 02/350 ...! :eek:
Do you think it's good idea?
 
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Hi Atupi
I think is better a more heavy enclosure than mine,because as suggested this amplifier works bettet at low frequency with 300 watt transformers
So is better to use a stiffer enclosure for heavy transformers
I know but this enclosure i have it already and i dont want to spend more money. I have a custom made toroid 4x24v 350VA low induction core and i will use it.
Unfortunately i have no opportunity to listed loud, my neighbours would kill me.
 
Hooked up and playing music

:eek:I was playing around with Micromega Myamps bridged. Like it, but put the FE Evo back this morning.
Using three chassis. Both FE boards are in larger box. The power transformer are in the two smaller. I have an old picture of the inside. Will post.
 

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I have applied the evo A mods,add two big 25 volt 6 ampere surplus talema transformer,and and few better components in the crucial place
(...)
It sound now very ,very good.
A lot of detail,armonious and fast
I think that the transformers help the amplifier to play very well at low mid frequency that are fast and articulate
It works with low frequency as 100 watt amplifier,very clean


Fine :)


Did you also re-routed LM3886 pin 7 to power ground? It's part of the Evo Rev A mod on the original Evolution and gives a nice performance increase (in the FE is already done).


Also critical to have better performance is to improve the LM318 power supply, you can retrofit P2P the FE PS to your board.
 
Conversion transformers

I can't understand the wiring of those silver cans well, but they could also be small coupling transformers. Please, do not keep us in suspense!
ciao g

They block dc plus;
Convert the balanced output from dac/interface to single ended.
They also do the impedance conversion of Pro to consumer.
And are 4:1 step down to manage overall gain.
Cinemag CMLI 10/600.
 
Fine :)


Did you also re-routed LM3886 pin 7 to power ground? It's part of the Evo Rev A mod on the original Evolution and gives a nice performance increase (in the FE is already done).

No i didn’t,i wil do it
Thanks!!

Also critical to have better performance is to improve the LM318 power supply, you can retrofit P2P the FE PS to your board.
Next time i want to build an exetrnal board for the power supply of lm 318
Dario the earth of 220volt go directly to the chassis of with a resistor 10/50 ohm?
(Or better but absolutely non shure do not use the earth?)
 
They block dc plus;
Convert the balanced output from dac/interface to single ended.
They also do the impedance conversion of Pro to consumer.
And are 4:1 step down to manage overall gain.
Cinemag CMLI 10/600.

Cinemags are very nice. I should have recognized them, but the one I used on another project are the pcb type. Its interesting to see how much better bandwidth the 4:1 Cinemags have compared to the 1:1 Cinemags (my project).

I did my balanced to SE conversion with an opamp and at 1:1.

Jac
 
Cinemags are very nice. I should have recognized them, but the one I used on another project are the pcb type. Its interesting to see how much better bandwidth the 4:1 Cinemags have compared to the 1:1 Cinemags (my project).

I did my balanced to SE conversion with an opamp and at 1:1.

Jac


My overall system gain is too high. The speakers are over 100 dB. I listen at mW levels.
Jensen has a 8:1 line input that looks promising. JT-6110K-B. If bridged FE Evo gets built I will try then.
 
Anyone can help me with what is the correct direction to install the C13 input caps model CDE 940C? Couldn't find this info on this thread or build tutorial. Thanks!


For the my 940C signal follows markings direction.


This could be different from the build tutorial, I'm revising things and now that I have an oscilloscope I'm able to find out the outer foil for sure ;)