I have made a 3875 dual mono chip amp with the two transformers in one box and the two channels of the amplifier in another box. I have noticed that when I let the ground of the amplifier channels float (not connected to their box which in turn is connected to the ground of the power supply box) the soundstage is a bit bigger but the background is not as black. I was thinking of placing a 10 ohm resistor between the ground of each channel of the amplifier and the box in the hope that this will prevent cross-talk (maintain the wider soundstage) while reducing the noise in the background. I thought his would be a way of mimicking having mono-blocks. Does this seem to you a good idea? Is there a better way to achieve my goal?
Where is the rectifier? Which box?
This sounds all wrong anyway. I take it these are steel boxes? The incoming safety ground should connect to the txfrmr box, nothing else. The secondary centre tap or DC ground is exported individually to each amp PCB, no connection to the amp box is required.
This sounds all wrong anyway. I take it these are steel boxes? The incoming safety ground should connect to the txfrmr box, nothing else. The secondary centre tap or DC ground is exported individually to each amp PCB, no connection to the amp box is required.
Thank you for your response, Counter Culture. The rectifiers are in the amp box. The boxes are steel. The incoming safety ground is connected to the transformer box, but I have connected this point to the amp box (so that the amp box would shield the amplifiers that are in it). The issue, as I understand it, is whether the ground plane of the amplifier should be connected to the amp box and if so whether a resistor can help with any possible crosstalk.
Hi,
Maybe you can try this, figure 4 :
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
With dual mono, use one safety loop breaker per side :
http://www.diyaudio.com/forums/chip-amps/262633-one-two-transformers-4.html#post4099109
Phil.
Maybe you can try this, figure 4 :
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
With dual mono, use one safety loop breaker per side :
http://www.diyaudio.com/forums/chip-amps/262633-one-two-transformers-4.html#post4099109
Phil.
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