reduce Electrocompaniet EC 4 Gain

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Hello !

I have a pair of AW 60 blocs that are configured for mono use and a EC 4 as a preamp and they have way too much gain, moving the volume only the slightest with a regular cd player gets my 66 studio monitors way too loud and they're no sensitive speakers at all.
EC actually put out several versions of the aw-60 and they had different gain values so I started by getting both blocs to match the lowest gain version they offered (I used one I worked on before as an example). This gives me a little improvement but it's still too much and I would like to reduce the gain of the preamp as well. As there are no schematics out there I'm in need of some guidance.

Does anyone have a schematic for the gain stage, or have any idea on which resistor values to play with in order to reduce the overall amplification ?



Thanks :)
 
I know how it works and could easily do it, sansui did this in some of their earlier amps, they attenuated each source input differently and than amplified them all the same amount through the phono stage while applying the riaa equalisation through the feedback loop, also connected to the source selector, only to the phono input.
Although I absolutely love the sansui AU-222 and 555 I don't think this would integrate well in the EC design. I would like to just be able to calm down the gain stage of the preamp somehow, by changing the feedback resistor for example, only I don't know which one it is as I don't have a schematic.
 
Well, a little bit of patience and careful tracing always pays off :).
I found the two feedback resistors for the inverted and none inverted amplification stages (R41 (141 for the other channel) and R42 (142) on the EC-4 for those that would like to do the same thing) and changed them from 8.2 to 3.3k, and I might even get down to 2.2k to reduce gain by almost 4. This should calm things down quite a bit !
 
You can still try to attenuate the signal at AW60 input. Listen to both solutions and decide which one you like best.
Regarding the oscillations: the problem is that in most cases you will not detect them by ear because they occur at high frequencies. Far beyond from what our ears can detect.
 
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