My_Ref Fremen Edition - Build thread and tutorial

[davym]

Very nice! I see you have a Tocos pot fitted, i recently swapped a minature DACT stepped attenuator for one of those and it's way better.

 

[bitoman]

Thank you.
yes my first pot was one of those too.Failed quickly.It doesn't like fiddling.
This one is built much better

 

[lehmanhill]

Very nice, indeed. I like the way that you have combined the wood and metal. Much more artistic than my poor attempts.

Jac

 

[Kreisky]

Hello to everyone,I just thought I would share.I got this far about a year ago and haven't done anything to it since.It's hard to take apart once it's playing.
I can say this.It's the only thing in the house that I can play for extended periods of time at louder levels without the wife stomping over and turning it down. I don't know what it is but man this thing is Sooooo easy on the ears.I have other lm3886 amps in the house but compared to this,they kinda make you wince after awhile and I end up turning off...much sooner.
I'm very happy I built it.
Thanks to you all

On top is a b1 buffer SALAS board that I've had for years and recently finished after getting inspired by the Myref freman.

Nice box Bitoman, I would like to know how My-ref sounds with DCB1 as I hope one day building an active crossover based on DCB1...

 

[atupi]

I ușe dcb1>myref fe and it sounds very good

 

[davym]

Me too, they are a good combination.

 

[Kreisky]

Nice

Thanks for your advice !

 

[thunderchicken]

Does anyone have a working Mouser shared project link for a premium build?


Sent from my iPad using Tapatalk

 

[freegianmaria]

Hi all.
Simple question: using a 300va rcore transfromer instead of 120va rcore should improve or affect the sound quality of the amplifier?
Thank you for any reply.

 

[ClaveFremen]

Simple question: using a 300va rcore transfromer instead of 120va rcore should improve or affect the sound quality of the amplifier?

Never tried but it should be, as for toroids.

Maybe a bit overkill...

 

[ClaveFremen]

Does anyone have a working Mouser shared project link for a premium build?

The BOM has been updated with available parts (for C32 use the alternate code), simply copy and paste on the Mouser import tool.

BTW

Mouser project (order 2) (also here replace C32 with the alternate code)

 

[lehmanhill]

Never tried but it should be, as for toroids.

Dario is referring to guys like Bob who compared toroid transformers at roughly 160 and 300 VA. If you are curious, dig back into the posts in the FE RC thread. As I recall, Bob found that the bigger toroid sounded better, bass I think.

Like Dario, my understanding is that R-core transformers are more efficient and don't need the big size, so it might be a little overkill.

Jac

 

[AndrewT]

I don't think that Rcore/Ccore/Toroid are any different for efficiency. They all use a continuous strip to form the laminated core.
EI due to the way they use the stamped laminations are slightly less efficient.

 

[ivanp71]

Potentiometer

Hi,
what potentiometer for this Fremen Edition? where insert it in the circuit?
Thanks

 

[thunderchicken]

The BOM has been updated with available parts (for C32 use the alternate code), simply copy and paste on the Mouser import tool.

BTW

Mouser project (order 2) (also here replace C32 with the alternate code)

Awesome, thank you!

 

[davym]

Hi,
what potentiometer for this Fremen Edition? where insert it in the circuit?
Thanks

10k works well, fit it to the line in audio feed (before the amp boards) or use an external volume control/passive pre unit. Whatever suits you.

 

[ivanp71]

Thanks for the clarification. However I have another question: The capacitor C21 is not in the project Mouser which is an alternative? Thanks

 

[lehmanhill]

Thanks for the clarification. However I have another question: The capacitor C21 is not in the project Mouser which is an alternative? Thanks

Ivan,

Great point. First of all, C21 is a bypass cap for C9. It is optional. If you use a Blackgate cap for C9, you won't need C21. Even with other C9 caps, using C21 would be builder's choice. The amp will work fine without it.

One possible alternative that is available at Mouser, at least at the US website, is the 63 volt version (505-FKP20.022/63/2.5). That should be fine in that location. Just search on FKP2 and 0.022 uF on your local Mouser site and find the 5 mm lead spacing parts available.

Another alternative that should be fairly good, although I haven't tried them in this location, would be the Vishay MKP1837 (well respected) which is available at Mouser (75-MKP1837322161). It is a metalized film cap (MKP) where the Wima is a film/foil (FKP) which should be a bit better sounding.

Have fun with your build.

Jac

 

[ivanp71]

Thanks Lehmanhill,
I understand perfectly thanks to your explanation as precise as elementary. I am sure that during the construction will ask again for your help.
Ivan

 

[ClaveFremen]

The schematic link on the GB's opening post has been updated with the 1.2 version.

Another alternative that should be fairly good, although I haven't tried them in this location, would be the Vishay MKP1837 (well respected) which is available at Mouser (75-MKP1837322161).

While highly regarded I would not use MKP1837s... they tend to hide details...use FKP2s