The hum-breaking resistor will help a lot. It eliminated the hum on my Aleph J.
This choke could work as well, to reduce the hum on DC rails. 159ZJ Hammond Manufacturing | Mouser Australia
Hi, guys.
I have some trouble with my Aleph j.
Everything was great one week ago. When i came back from business trip, i switched it up and heard noise in the left channel tweeter.
I have measured bias and offset in both channels. Bias is ok. Right channel offset is constant (2mV). Left channel offset is dancing from -8mV to 6mV and it always changes. I think it is the reason of the noise, but who is guilty for it? Offset variable resistor? When i rotate it, offset changes with jumps, not smooth.
The noise has variable frequency and volume level. Like a wind.
Please give me an advice, how to fix it.
I have some trouble with my Aleph j.
Everything was great one week ago. When i came back from business trip, i switched it up and heard noise in the left channel tweeter.
I have measured bias and offset in both channels. Bias is ok. Right channel offset is constant (2mV). Left channel offset is dancing from -8mV to 6mV and it always changes. I think it is the reason of the noise, but who is guilty for it? Offset variable resistor? When i rotate it, offset changes with jumps, not smooth.
The noise has variable frequency and volume level. Like a wind.
Please give me an advice, how to fix it.
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I have some Aleph 30 boards that I built many years ago and since removed for another build. I want to build an Aleph again, preferably the Aleph J but the store is out of boards. I distinctly remember somewhere on this forum Nelson telling how to convert the Aleph 30 over to an Aleph J but I have no idea where to find it again. Anyone have a better memory than me?
Is post #9 what you were thinking of?
https://www.diyaudio.com/forums/pass-labs/267857-aleph-design-reloaded.html#post4184920
Also ZM's classic A30 to AJ conversion pdf here:
https://www.diyaudio.com/forums/pass-labs/263951-aleph-30-noise-channel.html#post4121767
https://www.diyaudio.com/forums/pass-labs/267857-aleph-design-reloaded.html#post4184920
Also ZM's classic A30 to AJ conversion pdf here:
https://www.diyaudio.com/forums/pass-labs/263951-aleph-30-noise-channel.html#post4121767
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I believe so, many thanks. I just figured someone has a better memory than me. I built the Aleph 30 many years ago and since then I like to believe that I have better skills now especially matching the output mosfets. I did notice comparing the Aleph 30 vs the Aleph J that the damping factor is much higher with the Aleph 30 than the aleph J. I think that one thing that improves the damping factor is the 6 output devices per channel. Converting my Aleph 30 to the Aleph J may produce the best of both worlds.
Probably a silly question, but: Can I build these as monoblocks and run them balanced? If so, do I expect 50W per channel or more?
I'm fairly new to building electronics (B1 and Whammy so far..)., so please understand that. I also really need amps with balanced inputs, due to the horrible EM/RF/I here.
I'm fairly new to building electronics (B1 and Whammy so far..)., so please understand that. I also really need amps with balanced inputs, due to the horrible EM/RF/I here.