Aleph J

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#13
Puzzler. I built an Aleph J 6 months ago and it's been working brilliantly. And then I turned it on for the day's listening and nothing. In sorting things through I discovered the fuse on the AC common side was blown. If I replace the fuse, the amp board board leds light up a little but not the power supply leds on either side and then the fuse blows again. No burned or discolored parts. Checked all the push on connectors and terminal screws for tightness. They were OK. Couldn't find any wayward wires. When I continuity checked the wiring from the AC input to the terminal blocks before the transformers I got a puzzling result. If I put one multimeter probe on either hot or common side AC inlet and the other end on any of terminal screws (plus or minus) I get continuity. Minimal electronics knowledge here but I would think these would be separate. At any rate, there must be an incredibly simple answer as to why this isn't working. Ideas?
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#16
On a different Aleph J topic, are there any hacks for increasing bass response? I've paired it with the B1 Korg and a Wayne's Linestage. Better bass with WLS but seems like it could use a little more. I'm not looking for heavy rock type thundering bass. Speakers are horns w/ 15"woofers.
 
#19
getgoin said:
Puzzler. I built an Aleph J 6 months ago and it's been working brilliantly. And then I turned it on for the day's listening and nothing. In sorting things through I discovered the fuse on the AC common side was blown. If I replace the fuse, the amp board board leds light up a little but not the power supply leds on either side and then the fuse blows again. No burned or discolored parts. Checked all the push on connectors and terminal screws for tightness. They were OK. Couldn't find any wayward wires. When I continuity checked the wiring from the AC input to the terminal blocks before the transformers I got a puzzling result. If I put one multimeter probe on either hot or common side AC inlet and the other end on any of terminal screws (plus or minus) I get continuity. Minimal electronics knowledge here but I would think these would be separate. At any rate, there must be an incredibly simple answer as to why this isn't working. Ideas?
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first thing first

whatever you did with IEC (internal fuses), you really need to have separate dedicated fuse(s group) for each Donut

calculating value of those is simple - DOnut VA/mains voltage, then choose nearest standard value

then, when all is OK, ohmmeter should show properly few ohms for each primary, plus value of NTC you did use as soft start; simple shorting of NTC with wirecrocs should show just primary Rdc

much clearer when you have arrangement as described, which is also important for safety reasons, and - not unimportant for assembly and testing, it's much easier to work on just one channel at a time, simply having other one defused

if going that way, and you want to keep that fused IEC, just put double value fuses in it (meaning - calc both Donuts VA. divide with mains)
 
#20
getgoin said:
Here are some closeups of AC blocks
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You need a phillips screw driver to fix your terminal strips.

1 - Did you wire the mains "hot" with the black wire and mains neutral with the white wire? Mains "hot" should go to your trans primary red wires, and the mains "neutral" to your trans primary black wire.
2 - Your yellow safety cap is perfect along with your CL-60's!
3 - Move your trans primaries so that both black wires are on the same phillips screw, the outer terminal strip with the Cl-60 in series and both red primary wires on the same phillips screw on the other outer terminal strip. Just flip one of your ring terminals upside down and mount the other ring terminal so it sits flat on top of the other ring terminal, you want them up and down, not side by side. The screw will tighten and stay tight that way.

Regarding your IEC, not sure what you have there, just don't swap the mains "hot" with the mains "neutral" in the fuse circuit. Your on-off switch should switch mains "hot". I hope it's a high current one since you have dual mono P/S.
 
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