ah so one side would run slightly higher rails? any psu boards exist for such that someone would recommend?
Yes, diode bridges. Each secondary is followed by two bridges, one for left channel, one for right channel. Behind every bridge there is a 36.000uF KEMET elco, so there is also four of those.
See post 2128 and 2199.
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Ok, interesting. Is a double bridge on one secondary a way to increase channel separation ( in an audible way)?
It was a weighing of several factors, some in favor and others against. I don't remember what factor I ultimately found most important. I am satisfied with the result.
Two completely separate monoblocks are the way to go. But two chasis and two power supplies is the price to pay for best stereo separation.
Personally, i do not care about that, since two speakers in room have naturally terrible crosstalk.
I'm not interested in a Halcro amp, but that sample track by Mary Webb sounds pretty good!
I bet it would sound REALLY good played through a Wolverine.
😎
I was thinking possibly one channel getting +/- 53V rails and another channel getting +/-55V rails since the dual center tapped secondaries aren't linked, one channel just clipping a bit sooner. Only planning driving tweeters anyway so dont need big power. Would this work?
Sure. These are basically just honking big opamps which are not particular about supply voltages.
Cool thanks. The DIY audio store PSU board is not suited to this arrangement though, does anyone know of a fully dual mono PSU board? Or would I need to just purchase two of the DIY store PSU boards and try and fit them in?
^ I'm not sure if he's got a 'dual-mono, dual-rail' filter on a single board, but you can try @rhthatcher ... He's got some nifty stuff, and his boards are top notch IMO. I used two of his 'V8' boards for a dual mono supply, and I'm thrilled. At one point he had some single rail boards that would accommodate some fairly common 50mm caps also....
Hi Guy's,
A few weeks ago @mainframe99 made a suggestion that sheet 2 of the BOM include the requirements for Drill / Tapping
of the Heatsinks for both the EF3-3 & EF3-4 boards.
Sheet 2 of the BOM has been updated with that suggestion. Thank you @mainframe99 for your contribution. 👏
The Dropbox folder has now been updated.
1st GB Updated BOM 2023 September 29
2nd GB Updated BOM 2023 September 29
A few weeks ago @mainframe99 made a suggestion that sheet 2 of the BOM include the requirements for Drill / Tapping
of the Heatsinks for both the EF3-3 & EF3-4 boards.
Sheet 2 of the BOM has been updated with that suggestion. Thank you @mainframe99 for your contribution. 👏
The Dropbox folder has now been updated.
1st GB Updated BOM 2023 September 29
2nd GB Updated BOM 2023 September 29
I used a similar board (same designer I think - Prasi, since was nice enough to provide Greber files) and being <100mmx100mm it's cheap to get made at JLCPCB.com (with shipping 10 boards was ~$20. You "could" always use two want to have 8 caps and double the capacitance you can put in the amplifier, or use a dual-mono set-up. Overall the boards are barely larger than the 4 caps, so they don't take up much room in the chassis.
For caps - I used 80V 12000uF Chemi-Con (Mouser part# 661-ESMH800N103MA50S) - they are <$5/ea for 10+ in the US and never had an issue with them.
Thanks.
Just curious, if you wanted to make the Wolverine a balanced amp, you would need 2 boards per channel? Then you hook up the positive of one side and the negative of the other, then ground the 3rd pin to the chassis? Or is there more to it?
Also, I do want to have XLR inputs on my amp. Is the best way to do that, without going fully balanced, by using small input transformers with the XLR? Can anyone point me in the direction of a board for those? Or is it just best to stick with RCA inputs?
Just curious, if you wanted to make the Wolverine a balanced amp, you would need 2 boards per channel? Then you hook up the positive of one side and the negative of the other, then ground the 3rd pin to the chassis? Or is there more to it?
Also, I do want to have XLR inputs on my amp. Is the best way to do that, without going fully balanced, by using small input transformers with the XLR? Can anyone point me in the direction of a board for those? Or is it just best to stick with RCA inputs?
Well, if you want to bridge two channels, and you want a balanced (differential) input, then you are all set. Hook one signal lead to one channel and the other signal lead to the other channel, hook the grounds all together using good grounding practice, and run the speaker between the positive outputs of each amp. Voila!