My_Ref Fremen Edition RC - Build thread

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Transformers

As my speakers are roughly 4 ohm, I'm using Antek 22V, 300 VA, one per FE for now. The future plan is to experiment with driving more than one amp in parallel to better understand the hum thing.

As you probably can't see in the picture, I am using most of the premium components. As the reported big difference in the True Copper to K71-4 caps is in the bass, I went with the K71-4, since the subwoofer handles the deep bass. I have some K75-10s to try that were recommended by one of the guys on the solid state forum.

Otherwise, I have the Riken for R10, all three Ero caps, the Elna RJH, etc. At the moment, C9 are BG STD. I have sockets for C9 with a plan to try Niobium and BG PK caps. Also, the NP caps from Soonsc if they work out.

Jac
 
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Wow, That all sounds excellent. I'll just add the the True Coppers also do a lot for image and clarity, but I haven't heard what you are using so I can't make a comparison.

I have a sub with a big amp also and am considering tying it in just for those giant room shaking pipe organ notes. That is more for the vibrations than the sound. Madisonears is doing some interesting work with a bi-amp system with MyRefs on top.

Are you getting any hum from the setup you have now?
 
Been waiting to hear that for a long long time. See Dario, I'm not nuts and it's not just your imagination. :D

No Bob, simply Jac entered the collective illusion... it seems he took the red pill...

This is your last chance. After this, there is no turning back. You take the blue pill - the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill - you stay in Wonderland and I show you how deep the rabbit-hole goes.


:spin:
 
Made good progress this weekend. Need to order a few missed parts but I should be present in the RC room by Tuesday, :xfingers:
 

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Congratulations. I've never heard anyone mix together the Matrix and Dune. That combination just twists the mind.

Don't forget that the citation from the Matrix is, indirectly, a citation of Alice in wonderland... just to add complexity :spin:

BTW the Matrix borrowed ideas from a lot of novels, including Dune novels... ;)

Here an example.

Besides, I like the red pill.

Me too, Suburra gave me mine some years ago... :rolleyes:
 
I'm using the same as Bob. I have Randy Slone's old book on building power amps. He suggests using both a fuse on the mains side of the transformer, plus one for each rail on the transformer side of the smoothing caps. I've done that in the past, but I'm not sure there isn't a negative effect on sound due to the impedance of the fuse and extra wiring. This time, I just used the mains fuse.

Any other thoughts?

Jac
 
I'm waiting for a pair of lm318 for solve the problem of first channel, but unfortunately today after one hour of listening, the second channel has stared to playing some bad intermittent distortion.
When I power on the unit, the relay switch on and off after a pair of second.
I've tried to measure DC offset but the value is variable.

Have you any useful tips?

Roberto
 
Yesterday I've pluged to mains the unit and today all was in order so I connect it to speaker, and all is ok! :)

Today I've also received the LM318M for the other channel, but I've found a surprise...
The chip don't have the pin orientation sign!! :(
So I've 50% of possibility to install it in the right way... and maybe I've also to consider Murphy's law... ;)

Roberto
 

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The chip don't have the pin orientation sign!! :(
So I've 50% of possibility to install it in the right way... and maybe I've also to consider Murphy's law... ;)

It's not so... you have the dent:

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BTW it's strange... are you sure that distrelec shipped natsemi part?

Can you see the natsemi logo on chip?
 

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Thanks Dario, I've found the dent with a lens.
I've bought two National LM318 and, I've just noticed, one has the round sign and the other the dent, both are MWAB LM318M with National logo.

I've substituted the LM318, but DC offset is always 60mV and sometime on start the relay don't wake up. So, the story is unvaried and maybe the problem is elsewhere.
 
C12 position

Well I am finally soldering up the boards. A quick question though. C12 is not a polarized cap correct? That being said is there a preferred installation? I have the Amtrans 73778. In looking at the schematic, polarized cap installations are clearly marked with a + as is the circuit board. However, I noted o's on some of the other cap diagrams on the board. What is this? Clearly a newbie here. Thanks.

Paul
 
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