Help !! ELECTROCOMPANIET EC-1 preamp

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dray177

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Joined 2008
wtconcept.com/levinsonml2/
My new preamp, an Electrocompaniet EC-1, have one noisy phono channel.
Not hum, but cracklings...

In order to solve this problem, I would like to find schematics, diagrams, ...

Of course, I asked that to Electrocompaniet Norway, but without success.
And I am not astonished by this no reply ; all companies are doing so, except AUDIO RESEARCH !!!

Perhaps You are able to provide help ?
I hope

Raymond

My EC-1 :
An externally hosted image should be here but it was not working when we last tested it.
 
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dray177

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Joined 2008
wtconcept.com/levinsonml2/
Halols, mjf and Gorgy, THANK to You !!

- I will try today or tomorrow to contact sir Abrahamsen but without good hopes because my English is a bit poor ( if I was Norwegian like you it will be more easier with phone to get a nice reply !! ).

- on DiyAudio, nothing appear about EC-1 ; only one other guy, like me, is trying to get schematics.

- Of course, I verified before all electrolytic C and changed all these out of specifications ( around 16 C 22µF/63v were so ! ) but no amelioration ; in addition with a magnifying glass, no dry solder found.

This is why I am searching then schematics for understanding circuitry !
Raymond
 
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dray177

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wtconcept.com/levinsonml2/
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dray177

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Joined 2008
wtconcept.com/levinsonml2/
mjf said:
if i understand correctly it is only one channel of the phoneamp that is crackling.......
annother reason for that can be a bad contact........the source switch,can be cleaned with a contact spray or so...........
greets
Click to expand...

Thanks mjf for your interest.
Crackling become visible ( with oscilloscope ) in the middle of phono stage ( the right channel only ).
Then, no problem with source switch, volume & balance potentiometers.
In this case, only diagram can help me

Raymond
 
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dray177

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Joined 2008
wtconcept.com/levinsonml2/
mjf said:
hello.
can you give a little pressure (with your fingertip) on the bad channel so that the pcb is a little "bent trough"............if then the crackling changes it should be a bad soldering point or hairrent or bad contact..........
Click to expand...

Ooooh !
Of course I do that, little pressure and small bumps on pcb and on all components one by one located on this phono channel.
And resoldering all questionable...
Raymond
 
tiefbassuebertr

tiefbassuebertr

Member
Joined 2005
tiefbassuebertragung.de
ask additional there
HIFI-Studio Wittmann in Stuttgart: Nehmen Sie Kontakt mit uns auf ... (Service Center Electrocompaniet Germany)
audiocostruzioni.com
and by this private sellers:
Electrocompaniet "EC-1" Preamplifier - Canuck Audio Mart
Electrocompaniet pre amp EC1 (Used)
Electrocompaniet preamp - help requested - AudioKarma.org Home Audio Stereo Discussion Forums
because in early days electrocompaniet release the schematic in general (together with the owner's manual).

A formerly employer from EC had a website some years ago with all their schematics online. But Electrocompaniet say, all schematics must remove. I don't know his name. Perhaps an other guy know this. Then you can try also ask there.
 
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dray177

Member
Joined 2008
wtconcept.com/levinsonml2/
tiefbassuebertr said:
ask additional there :
...
...

A formerly employer from EC had a website some years ago with all their schematics online. But Electrocompaniet say, all schematics must remove. I don't know his name. Perhaps an other guy know this. Then you can try also ask there.
Click to expand...

Many thanks Andreas, I will contact all !!!

Yesterday, I repaired it with an enormous lot of chance.
They were not at all bad electrolytics, semi-conductors, soldering, switches, potentiometers, ...
Only in need of adjusting DC offset voltage in phono circuitry ( don't ask me why, I have no diagram for understanding that !!!!!! ).
And now phono stage are very very quiet.

Here my EC-1, top plate removed :
An externally hosted image should be here but it was not working when we last tested it.


And below a pic of the 2 phono stages ( on the left, from upper to below, the left phono channel ; and on the right, the right channel ) :
An externally hosted image should be here but it was not working when we last tested it.


The trick is to adjust ( after the warming delay ), with the help of the 2 red trimmers ( for left channel this one just below "R78" lettering ) 0.0volt on the ouput ( this one just below "R63" lettering, for the left channel ) of this one ( the 4 blue "Siemens KP100000H" capacitors ). For the right channel you have to choose the opposite on the extremly right !!!

But I still woul like to find schematics for understanding that.
Raymond
 
homemodder

homemodder

Disabled Account
Joined 2006
Dray177, maybe you could back engineer and trace us that circuit, I would love to see the schematics too, from your pics I can see lots of high quality parts, products from this company usually have exceptional sound quality. Ive got a couple of amps from electrocompaniet but no preamps, if your ever in future think of selling it drop me a line, your preamp looks like you took good care of it and is in perfect condition.
 
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dray177

Member
Joined 2008
wtconcept.com/levinsonml2/
homemodder said:
Dray177, maybe you could back engineer and trace us that circuit, I would love to see the schematics too, from your pics I can see lots of high quality parts, products from this company usually have exceptional sound quality. Ive got a couple of amps from electrocompaniet but no preamps, if your ever in future think of selling it drop me a line, your preamp looks like you took good care of it and is in perfect condition.
Click to expand...

I am not skillfull for re-tracing circuit ( indeed very complex with many semiconductors ).
But, me also, I would like to have this diagram on my table.
And you are right, now, this EC-1 looks like as new

My Son wish for comparing it with its Kenwood L-07CII preamp, associated with a very nice THRESHOLD Stasis 3.
Restored it also, last month
Its Stasis 3 for repair :
An externally hosted image should be here but it was not working when we last tested it.

And now :
An externally hosted image should be here but it was not working when we last tested it.
 
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dray177

Member
Joined 2008
wtconcept.com/levinsonml2/
analog_sa said:
It will be easy to reverse the circuit if you publish a similar photo of the solder side.
Click to expand...

Oooooh !
I don't think so, not at all easy with these recto-verso PCB.
And there are a so great number of components.

I tried a bit in order to understand and solve my problem, but I losed my way very quickly.
In this case the best is to use an oscilloscope for tracing the noisy signal...

Raymond
 
tiefbassuebertr

tiefbassuebertr

Member
Joined 2005
tiefbassuebertragung.de
supplement to my post #12:
Now I have found the name of the formerly EC man and his own homepage:
The Sandstrm Audio Site
please contact Terje@osiris.no
Actually he must have the EC1 schematic in the PDF format

Two years ago he send me this reply:
"Hi ! Regretfully current policies at EC says that the schematics shall be not made public. They are therefore also removed from my site, even for the older amplifiers. This may of course be changed in the future, but I have no timeline on this. Best regards Terje"
 
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