Thank you in advance for your time and expertise here!
I'm the proud owner of a Luxman R-1050 Receiver I purchased new in 1977 along with a pair of Allison One Load Speakers.
The problem I'm having is getting my new Samsung 4K QLED TV and XBox One X (I'm using this as my 4K Blu-ray player) and Bose Wave connections to my Luxman right as I'm experiencing volume and clarity issues.
The Luxman has only RCA inputs, 2 Phono and 1 AUX inputs along with some Tape dubbing inputs I've never used.
The Bose is simply connected via a 3.5MM to RCA 2 channel adapter and plugged into the headphone jack of the Bose and the AUX of the Luxman. The only issue here is I have to turn up the Bose volume to 70% to get decent volume out of the Luxman, otherwise the quality of sound is good with no background noise.
The TV and Xbox are a bit more complicated as they have HDMI and Optical outputs only. So I purchased a pair of 2 channel eSynic (Model DAC022) Digital to Analog Converters (DAC) and used the optical out of the cable box as the TV seemed to just output and continuous clicking sound, I then connected that to the optical input of the DAC which then has RCA outputs to the Luxman. These DAC's are USB powered which I grab from the TV so they go On/Off with the TV. I used the second DAC for the Xbox where as the optical is attached directly to the Xbox.
Prior to the Samsung and Xbox I had a 6 year old Sharp Aqua 3D TV and I used it's headphone output directly to the Luxman Phono 1 and got good quality sound. Phono 2 had shorting plugs installed via the factory. I had a CD player attached to AUX at the same time also with good sound.
The Luxman, Bose , TV, and Xbox do not have ground blades on their power cords.
The Luxman and Bose are plugged directly into the wall outlet 20 or so feet from the TV and Xbox.
The TV and Xbox are plugged into a APC battery backup that is grounded.
With all inputs disconnected from Luxman and as I select Phono 1 or Phono 2 and raise the volume there is a faint HUM that increases. If I ground the Luxman in this state to earth the HUM stops.
With AUX all is quite with volume increase whether connected or not.
With all inputs connected to Luxman with TV and Xbox turned OFF and as I select Phono 1 or Phono 2 and raise the volume a loud HUM increases.
With all inputs connected to Luxman with TV ON and I ground the Luxman to earth I get an increased HUM.
TV and Xbox are plugged into Phono1 and 2 respectively and produce normal volume but a with muffled sound and a faint background HUM not a Buzz. I'm thinking maybe the HUM is causing the muffled sound, but not sure???
Nothing is grounded, so ground loop I don't think is the problem???
AUX gives good clarity but greatly reduced volume with Bose, TV or Xbox connected one at a time.
I checked the RCA output line voltage from the DAC for the TV and it was at 2.49 volts for both left and right channels, yet when plugged into AUX I get decreased volume. Yet the Bose output from the headphone jack was 0 volts with my multi meter set to 20 Volts DC and even at the most sensitive setting it was barely detectable yet enough to get good clear volume out of the Luxman so long as the Bose volume was pushed up to 70%.
I'd like to get the volume from the Phono inputs and the clarity from the AUX combined from one or the other if possible.
I suppose the DAC could be the cause of the muffled sound, but can't eliminate them to test otherwise.
I was hoping to find lower that 2V from the DAC thinking I could use an active pre-amp to boost it, if that makes sense??? But the voltage was fine.
Your comments and suggests are welcome, Thanks
