My_Ref Fremen Edition - Build thread and tutorial

This build thread associated with this GB:

http://www.diyaudio.com/forums/group-buys/229358-my_ref-fremen-edition-interest-group-buy.html

On the project's Google Drive folder it's available a PDF version of the tutorial, in addition to schematic, BOM, etc..

Also on 7/2013 I've added a video on YouTube of the SMD soldering part:

Apart support and sharing place for builders, goal of the thread is to generate content to complete the tutorial.

Builders, please post your experience, problems, pics and whatever related with your FE build... ;)
 
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A carryover post from the RC thread to reply to the board cleaning question. I have not tried the commercial products but here is my home-brew method.

I'm going to have to try Bob's Scrubbing Bubbles. I have been trying "Flux Off (Rosin)" which is an spray can with a brush tip. It cuts flux pretty well and the brush lets you get into tight spots. It does leave some residue which I try to remove with a toothbrush and alcohol.

The biggest trick for me is to clean up often as the flux seems to get tougher with time. For the FE, I cleaned up after soldering all the SMD bits, and again after the through hole parts.
 
The Scrubbing Bubbles is indeed for the residue after the major cleaning is complete.

I forgot to mention fingernail polish remover also works well. It is basically diluted acetone which, if used full strength can dissolve the boards outer layers and lettering. The standard brands the ladies use is safe and cuts just a bit faster. Just be careful.
 
I have been trying "Flux Off (Rosin)" which is an spray can with a brush tip.

I use a spray specific for PCB cleaning with the associated brush.

It works pretty well, I first spray the PCB, let pass some seconds and then brush it.

As a final touch I spray again to clean residues.

Compressed air is useful to remove quickly the sprayed liquid.

For the FE, I cleaned up after soldering all the SMD bits, and again after the through hole parts.

I do exactly the same.
 
Ok.. I am about to order thoser rikens and amch caps from parts connexion.

Regarding BG in C9... Parts Connecion has got 4V only 220uF

Can you confirm such low voltage is ok ?

From RC thread:
As Jac already noted there is still availability of the 220uF 4V BG PK.

They sound pretty good, better than BG STD and not far from BG FK/NX
 
Found answer..they fine :)

Dario, I remember you were cautious about Nichicon KG, but I might get them cheaper so would give them a try (if you are not against that decision :D )
Plus according humble cap test Jantzen superior Z is nice one to try, especially considering price, what do you think about that one ?
 
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Can you confirm such low voltage is ok ?

They're fine but in case of fault they will burn, so buy some spares.

It's better to mount them only after the amp is operational, for the first power on use any 220uF/50V you have at hand.

Dario, I remember you were cautious about Nichicon KG, but I might get them cheaper so would give them a try (if you are not against that decision :D )

Everyone is encouraged to experiment.

Just one note:
If you want that your experiment can be useful for others compare with BOM parts, BOM is our common starting point.

Plus according humble cap test Jantzen superior Z is nice one to try, especially considering price, what do you think about that one ?

I don't know, never tried them.

Just a note on Humble Home made cap test.

Those test are made on a HV application (crossover networks), on line level result may vary.

I would rather buy an Audyn Cap Plus, cheap and ,according Bob, very nice sounding.
 
Right.. voltage drop after transformer (rectification ?) is approx 34 V which seems to be too close to 40V specs of capacitor, so 63 V cap is the choice if I cannot find 50V specified.
Plus I must add into equation voltage forward drop of rectifying diodes ?

Or because they connected in parallel total V equals 0 ? And only rectified voltage of 34 V is going through ?
 
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Right.. voltage drop after transformer (rectification ?) is approx 34 V which seems to be too close to 40V specs of capacitor, .....................
That's not close. You have 6V to spare for transient spikes.

But more importantly have you measured the open circuit voltage of the transformer?
Have you then scaled that output voltage to what would appear when mains is at maximum tolerance of 254Vac?

Do that first.
Then model the smoothing cap voltage.
Finally select a capacitor voltage rating to suit.
 
Found answer..they fine :)

Dario, I remember you were cautious about Nichicon KG, but I might get them cheaper so would give them a try (if you are not against that decision :D )
Plus according humble cap test Jantzen superior Z is nice one to try, especially considering price, what do you think about that one ?

@Tom E,

Do I remember that you played with the Jantzen Superior Z and reported on another thread? If so, how did you use them and what did you think? Of course, my memory is not my strong suit, so I may be remembering someone else's comments.

Jac
 
Confused. Is there any difference between Audyn true copper blue or bronze coloured caps ?

Build date at least. Tom E., Bob, and Dario all bought the blue ones in 2012 or earlier. I auditioned Bob's blue one and it sounded nice. I believe the blue ones have a paper or foil wrapper.

For a different project, I purchased a pair of the bronze ones late last year. It appears that the wrapper for these is rather thick aluminum foil that has a brushed and anodized finish. This appears to be a style change for Audyn, but I don't know if it affects sound. Actually, I prefer the look of the blue because the bronze has an uneven and thick junction of the foil that looks cheap.

Unfortunately, I don't have the other project complete, so I can't comment on the sound. Also, they are a different value than usable for C13, so I couldn't try them in direct comparison to other caps.

Has anyone else tried the bronze TCs in C13? Especially with some other comparison of caps?

Jac
 

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