I would like to apologize for stating that the LM4780 Stereo/Parallel board (blue) was a bridged / stereo board. I think it is time for me to go to bed.
The enclosures are coming along nicely but as always when doing metal work it's a real pain not to have a proper shop to do things in. I bought a drill press from a local store earlier this week as it was on sale for a ridiculous EUR 54. Not that free hand milling is the way to do things but the precision was good enough for the mains receptacle which is the type with switch and fuse holder integrated (saved me two holes per panel 
).
I'm using the power supply boards I had left over from a pair of Chipamp LM3886 amps. The build is a three channel amp with one LM4780 stereo board that will be for tweeter and boomer. The parallel LM4780 (1) from this Beta Build will be for the woofer. I'm currently looking to replace the HifiDIY.net boards with stereo boards from Chipamp or Audiosector as I like the smaller boards and it would look just a little bit nicer. Not that it would be visible. The enclosures will be mirror image back panels and will be standing close to each speaker with a component video cable (which reduces cable clutter as it is effectively one cable but will carry three signals) connected to the 2x8 MiniDSP which I'll use as filter.
Transformers are Amplimo 2*22 VAC @ 160 VA which will be just fine per channel.
Next thing to source is some aluminium L-shaped extrusions I need in order to mount the boards nicely to the side profiles of the case. Why, oh why, doesn't anybody sell 10 and 35 mm aluminium extrusions with 1 mm thickness where I live?
Nah, it's cheese on a Max Burger from Sweden.
). I'm using the power supply boards I had left over from a pair of Chipamp LM3886 amps. The build is a three channel amp with one LM4780 stereo board that will be for tweeter and boomer. The parallel LM4780 (1) from this Beta Build will be for the woofer. I'm currently looking to replace the HifiDIY.net boards with stereo boards from Chipamp or Audiosector as I like the smaller boards and it would look just a little bit nicer. Not that it would be visible. The enclosures will be mirror image back panels and will be standing close to each speaker with a component video cable (which reduces cable clutter as it is effectively one cable but will carry three signals) connected to the 2x8 MiniDSP which I'll use as filter.
Transformers are Amplimo 2*22 VAC @ 160 VA which will be just fine per channel.
Next thing to source is some aluminium L-shaped extrusions I need in order to mount the boards nicely to the side profiles of the case. Why, oh why, doesn't anybody sell 10 and 35 mm aluminium extrusions with 1 mm thickness where I live?
Nah, it's cheese on a Max Burger from Sweden.
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One thing with these boards is that the holes for power supply are a wee bit too tiny as I can't fit anything over 1.0 mm2. Cables sometimes are a pain to source but 1.5 mm2 standard 7 or 27 strand mains installation wires are easy to source and cheap. Unfortunately they do not fit so I would suggest slightly bigger holes for power supply and output.
I fully agree. Should there ever be a new batch of boards made, larger diameter holes for power, grounds and output would be very beneficial.
Slowly working my way forward towards a working amp. Another weekend coming close so perhaps some progress in a few days. Anybody else?
As for feedback on the boards itself I would say that I would have been really pleased to find either some surface mount pads or holes for the standard 220 pF caps that protect against EMI/RFI as I suspect some people will use these amps connected to MiniDSP and similar which sometimes emit residual switching noise. The caps I suspect would make that problem a bit smaller. It could be omitted for the less is more crowd.
As for feedback on the boards itself I would say that I would have been really pleased to find either some surface mount pads or holes for the standard 220 pF caps that protect against EMI/RFI as I suspect some people will use these amps connected to MiniDSP and similar which sometimes emit residual switching noise. The caps I suspect would make that problem a bit smaller. It could be omitted for the less is more crowd.
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The amps are finished. A big thanks to ChipAmp and Joe for the Beta Boards. My boards were incorporated into a three channel amp where the Beta boards are used for the bass channel and a normal two channel LM4780 board (from AudioSector) is used for the mids and highs. The filter used will be a MiniDSP 2x8.
My feedback is the following:
1. The power supply holes are two small as mentioned earlier. Nothing over 1 mm2 fits easily.
2. I'd love for normal size resistors (i.e. 10 mm pitch) to fit rather then the small profile (MRS16 et al).
Other than the above the boards are great and the quality exceptional. The amps sound great.
My feedback is the following:
1. The power supply holes are two small as mentioned earlier. Nothing over 1 mm2 fits easily.
2. I'd love for normal size resistors (i.e. 10 mm pitch) to fit rather then the small profile (MRS16 et al).
Other than the above the boards are great and the quality exceptional. The amps sound great.
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I recently added two 4700uF 200V Nichicon NY caps I had laying around to my setup, and I must say I'm impressed by the improvements they brought. The chipamps are fed by a regulated supply through maybe 0.5m long braided wires, same as before.
After adding the caps not only the bass got tighter, but also the highs seemed to have cleared up, and the whole amp sounds snappier. My gf agrees.
After adding the caps not only the bass got tighter, but also the highs seemed to have cleared up, and the whole amp sounds snappier. My gf agrees.
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