Questions about the EZ1290?

[user 125886]

I built an EZ1290, and am very happy with the final results. However, I was hoping if Martin, or anyone else, can clarify a few things for me?

The individual BA183 sections all have polypropylene and electrolytic capacitors. Does the audio signal ever pass through these electrolytic caps? Or, do they only go through the polypropylene caps?

Also, somewhere along the line, Martin decided to switch the polystyrene cap from the input transformer, to the output transformer. And vice versa, the orange drop cap on the output, was moved to the input transformer. Can anyone tell me what difference in sound that cap switch made? All Martin says in the build guide is that it sounds "better" to him. Does it make it have more presence? What difference in sound did that make?

 

[ruffrecords]

I built an EZ1290, and am very happy with the final results. However, I was hoping if Martin, or anyone else, can clarify a few things for me?

The individual BA183 sections all have polypropylene and electrolytic capacitors. Does the audio signal ever pass through these electrolytic caps? Or, do they only go through the polypropylene caps?

It goes through the electrolytics. The polys are mainly used for stability.

Also, somewhere along the line, Martin decided to switch the polystyrene cap from the input transformer, to the output transformer. And vice versa, the orange drop cap on the output, was moved to the input transformer. Can anyone tell me what difference in sound that cap switch made? All Martin says in the build guide is that it sounds "better" to him. Does it make it have more presence? What difference in sound did that make?

Transformers are funny things. Back in the day at Neve nobody worried or even thought about how various caps sounded. The only thing that mattered was did the console meet the required performance in terms of frequency response, distortion and noise. That's what those networks were designed to do and in particular to meet the frequency response requirements. Of course, they were selected for the transformers of the time and who is to say if the transformer used in today's DIY versions are the same.

Cheers

Ian