I have GAS thalia preamp in great shape. Works great, sound is solid. However, when something is connected to the AUX input, and I push in phono 1or 2 input I get substantial bleed through of the aux source in the phono inputs. Also A/B buttons seem to have no effect.
Probably it does not ground the unselected inputs, so the crosstalk would be normal.
Just turn off the other sources.
Just turn off the other sources.
Actually, the Thaila preamp does ground the unselected inputs. I would suspect the AUX switch has dirty contacts. OP, might try cleaning the switch with DeoxIT.
OP could try this test to confirm where the issue is. Move the source connected to AUX to the TUNER input. Then see if you get bleed through to the phono. If not that would prove a connection problem in the AUX switch.
THe bleed occurs with tuner as well on phono input), but bleed through when tuner input is on and aux selction button is pushed, Thus the blle only seems to be form phono input.
Have you connected anything to Phono IN1 or IN2 ?? They are sensitive inputs... if not used, load them appropriately (for MM / MC)... if you want to play...
yes I connect TT to them and they seem to work, although signal seems a bit low. as stated tuner or aux input seems to bleed to phono, but not to each other. could this be normal or is there an issue with phono inputs.
Try the "bleeding" test, only this time unscrew the turntable ground.
Even better, simulate the turntable cartridge load - either 100ohms or 47Kohms resistor (soldered to RCA connectors) will do fine... depending on the phono input setting MC or MM. Then try the bleeding test with AUX and TUN. This test isolates the influence of ground coupling.
Is the turntable and your AUX and TUNER plugged into the same mains outlet? If not, plug them into the same outlet and then try
Also, take a photo of that turntable (selector??) switch, and post it here. If NOT done with relays, then there might be dirt buildup that couples the sound across different inputs.
Even better, simulate the turntable cartridge load - either 100ohms or 47Kohms resistor (soldered to RCA connectors) will do fine... depending on the phono input setting MC or MM. Then try the bleeding test with AUX and TUN. This test isolates the influence of ground coupling.
Is the turntable and your AUX and TUNER plugged into the same mains outlet? If not, plug them into the same outlet and then try
Also, take a photo of that turntable (selector??) switch, and post it here. If NOT done with relays, then there might be dirt buildup that couples the sound across different inputs.
Ok, I did a quick search... is this your preamp?? if YES, remove all switches, open them, clean the dirt buildup, and reassemble. The metal glide rails, and the metal clips that make the contact, must be super shiny. You'll get the drift of what I'm talking about (if you haven't done this before) once you remove the top.
Good luck.
Good luck.
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removing the switches in this model requires top and bottom(switches are sandwiched between to PCB) desoldering of the push button switches. It is not as easy as I would have hoped.
Using a tool such as this may help.
https://www.amazon.com/YIHUA-Electr...d2-8cae-b4f39f9102a7&pd_rd_i=B094ZCRXMN&psc=1
Or how about this?
https://www.amazon.com/VISLONE-Auto...69&s=hi&sprefix=Desoldering,tools,173&sr=1-29
https://www.amazon.com/YIHUA-Electr...d2-8cae-b4f39f9102a7&pd_rd_i=B094ZCRXMN&psc=1
Or how about this?
https://www.amazon.com/VISLONE-Auto...69&s=hi&sprefix=Desoldering,tools,173&sr=1-29