My_Ref Fremen Edition - Beta build/Fine tuning

[ClaveFremen]

BLACK GATE F series electrolytic capacitor 220uf 50V 1pcs | eBay

Not exactly cheap but acceptable.

 

[bcmbob]

I just saw that. Not bad as I paid $6.00 ea for six standard back when they were readily available. Not sure if the difference is worth the $16 shippling.

 

[ClaveFremen]

I just saw that. (...) Not sure if the difference is worth the $16 shippling.

Black Gate FK costed, when I last saw them at a decent price, 16US$ each.

If F are at least 80% as good as FK I would buy them but I didn't tried them so I can't say...

 

[badrisuper]

Dario, I have other DIYer version of MyRef. When increase the volume to more than 70% its clipping. I am having 6400uF pannasonic caps. Using 10k DACT attenuator as volume pot. Using 6ohm Monitor Audio RX6 speakers. Do you have any idea why its clipping? Have you faced problem like this? Is clipping is normal? Has anyone faced this kind of problem? Sorry to post this kind of noob problems here in FE beta build. I am just a beginner learning things.

Thanks
Badri

 

[ClaveFremen]

I am having 6400uF pannasonic caps. Using 10k DACT attenuator as volume pot. Using 6ohm Monitor Audio RX6 speakers.

What is the voltage of your tranformers?

With 6 Ohm speakers and the My_Ref it's wiser to use 22-24V secondaries to avoid clipping.

Also 6400uF smoothing caps are way too low.

 

[badrisuper]

25-0-25, 225 VA I think.

 

[lehmanhill]

PCX Black Gate

I talked to the guys at Parts ConneXion today. I had already ordered some Black Gate PK, but forgot to order some Mundorf power supply caps. While I was on the phone, I asked him if he had enough PKs to fill my order. He replied that they have quite of few of those.

Just an FYI

 

[soongsc]

What is the voltage of your tranformers?

With 6 Ohm speakers and the My_Ref it's wiser to use 22-24V secondaries to avoid clipping.

Also 6400uF smoothing caps are way too low.

 

[ClaveFremen]

Can you translate?

 

[badrisuper]

I am just a beginner learning things.

Thanks
Badri

Soongc, Didnt get it?

 

[soongsc]

The impedance curve does nearly to 4ohms

 

[ClaveFremen]

The impedance curve does nearly to 4ohms

Thanks, so Badri should use 22V secondaries.

 

[bcmbob]

For the same reason the GND shall only be connected at one single point -- solder the four lugs of the RCA's together, the RCA barrels will provide the contact to the box.

It's all about keeping sending and receiving loop areas as small as possible.

* * * * *

Thanks Mr K. That is very clear. I'll be building one soon.

* * * * *

Well, what some people won't do while waiting for RC boards

2" x 2" x 1/8" leftover angle from hardware store.



Pre-building.



THE SECRET SAUCE (maybe snake oil) used as both glue and conductive filler. A line painted on paper doesn't indicate continuity but does read 1k resistance

ThinkGeek :: "Wire Glue" Conductive Glue

An externally hosted image should be here but it was not working when we last tested it.

Needle nose pliers and thin tips are a blessing.



Sides have lip cut on router table with carbide bit.

An externally hosted image should be here but it was not working when we last tested it.

Closed up with 6-32 rod and fancy nuts.


If I did it again I would use RCAs with hex on both sides. Note marks from pliers.

Well, You know what is said about idle minds.

 

[bcmbob]

Works as expected - sounds great!

Might make one for the eBay SMD pot.

 

[dudaindc]

Pretty neat Bob!

 

[bcmbob]

Thanks, it was fun to figure out how to keep it as small as possible. Been listening for an hour or so and the results are very impressive. Will prove to be a useful tool.

Good one to KSTR.

 

[atupi]

Russioan options for C13 cap

Another great cap for builders on a budget is the russian polystirene K71-4(film/foil).

Not as good as the Audyns but incredibly good for the price.

They're quite big though, they will not fit perfectly on board.

After reading this i'be bought K71-4 and i also bought some K40Y-9 caps. Tested both and for my ears K40Y-9 sounds much more musical. I would say polystirenes are much more analithical and a bit boring compared to PIO.
Just a feedback from my own experience.

Dario between Amtrans and the other NOS ROE/Vishay that you sold as a 4.5EU package what would you choose ?

 

[lehmanhill]

Thanks Atupi,

I was interested in the Russian PIO caps, but hadn't gotten around to ordering any. I think I'll order them, just to try.

Jac

 

[Milos P.]

K75-10 are even better than K40U(not Y )-9, IMHO.

 

[atupi]

I've bought also some K75-10 but installed in my Simplistic Phono RIAA preamp. They are huge in size compared to the others above but my RIAA preamp sounds really good now.