Hi guys,
just a quick question, does you're Aleph J produce any hum when its not connected to a pre-amp/buffer or some other kine of equiptment?
just a quick question, does you're Aleph J produce any hum when its not connected to a pre-amp/buffer or some other kine of equiptment?
@Zen Mod & tonistefanovski,
thanks.
then its back to the workshop for me 🙂.
ps. without any drawings....... i connected the ground of the inputs to GND3 instead of the GND next to the +in and -in, does this cause any problems?
thanks.
then its back to the workshop for me 🙂.
ps. without any drawings....... i connected the ground of the inputs to GND3 instead of the GND next to the +in and -in, does this cause any problems?
If you have dual mono in a single chassis then a thermistor per channel is a good idea.
You should also have input signal ground going to star ground. I think that's what you have shown but need to confirm it.
You should also have input signal ground going to star ground. I think that's what you have shown but need to confirm it.
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In my recent Aleph J build I’ve connected signal ground to main board… I’ve did that several times without problems… Always “dead silence”….🙂
Tony
I do have a dual mono setup attached to one power supply (diyaudio power supply).
I attached the PSU with one thermister to the chassis with a bolt on that same bolt i wired the savety earth.
thanks for you're answers so far. next week a collegue will help me with a scope to search for the hum.
I attached the PSU with one thermister to the chassis with a bolt on that same bolt i wired the savety earth.
thanks for you're answers so far. next week a collegue will help me with a scope to search for the hum.
Please also check your inputs (RCA or XLR); no direct connection to ground.
Pictures could help, if you have some.
Please post 'em.
Good luck !
Pictures could help, if you have some.
Please post 'em.
Good luck !
only RCA, and no connection to ground, i've put the fotos in an album on onedrive:
http://1drv.ms/1LK79gs
at the moment only the aleph J boards are connected, the photo's also show a Mez B1 board but it is disconnected at the moment for the sake of troubleshooting. when i short the inputs of the aleph J the hum disappears.
http://1drv.ms/1LK79gs
at the moment only the aleph J boards are connected, the photo's also show a Mez B1 board but it is disconnected at the moment for the sake of troubleshooting. when i short the inputs of the aleph J the hum disappears.
deHaai - is the hum equal in both channels? is it a low frequency hummm or more of a higher frequency hiss?
I use whatever I have on hand, and closest to what fits in the holes of the PCB.
For input wiring, coax or twisted pair is best. If you have an unused CAT-5 cable, open that up and you will find many strands of twisted pair perfect for signal wiring. 😀
Me too, 18 gauge is so much easier to work with so I am using it for all builds now.
today we diagnosed the hum problem with a scope and found that there is 0,4v of AC on the DC side of the psu, is 0.4v enough to cause a hum?
What was the frequency of the hum? 100Hz means supply born. 50 Hz means input born.
If its input born 50Hz simply make sure to use a piece of shielded cable between input and PCB. Or try to relocate the transformer.
If its input born 50Hz simply make sure to use a piece of shielded cable between input and PCB. Or try to relocate the transformer.
I've always used twisted pairs for PS wiring as well - 24/0 as pair and 0/-24 as pair, but I see you just ran straight wires for 24/0/-24. Any advantage / disadvantage for twisted pairs on the POWER side. (obviously very important for input)
What about OUTPUT? I usually twist them as well. I guess it looks neater, but does it really matter?
