Sony TAE-5450 preamp issue

[Tube Radio]

Several years ago the volume control on my Sony TAE-5450 went bad and I never did anything about it because at the time I had no need for the preamp.

The volume control is a 10K stepped attenuator.

I myself am not too fond of stepped attenuators as the volume changes in steps, although I know they are better than regular variable resistors.

Is there a reasonably priced stepped attenuator or regular dual gang higher quality variable resistor I can replace it with?

I have a need for the preamp now and want to get it working.

I know there's some stepped attenuators that have more positions than the stock attenuator, but I don't know if any of those will fit due to size.

EDIT:

Would this work as a suitable sub for now?

https://www.parts-express.com/ALPS-...vxmw_zXtbWb9RC93cjgeL0DYmZv4DWHxoCNyIQAvD_BwE

 

[Tube Radio]

Pot has been ordered.

Should be here some time next week. I'll install it at work since I have better soldering equipment there.

No it isn't the correct stepped attenuator, but I never liked those anyways and a good attenuator with a bunch of steps is more than what I can afford right now.

I do have a problem though.

I use an M-Audio Delta 192 sound card in my desktop PC which has balanced inputs and outputs.

I use a DBX 234XS crossover which feeds one Carver TFM-25 and TFM-15 amplifier.

When the Sony is connected I have a hum. The hum at one point would increase in level some as the volume control was turned CCW.

I can disconnect the cable from the sound card and the hum goes away.

I can connect the sound card to the crossover using the same unbalanced cables I used to connect it to the Sony and no hum is present.

When initially testing the Sony I had a tuner connected to the sound card's input using a M Audio fast Track pro USB audio interface as a preamp (USB not plugged into computer) to step up the audio level so that it is high enough for the sound card input as the sound card has no level controls to increase or
decrease the actual gain of the input.

Tonight I moved the tuner to the tuner input of the Sony and moved the sound card to the tape 1 output of the Sony.

I could use the Fast Track Pro as the sound card, but the Delta 192 is much better given it has a max sample rate of 24 bit 192 KHz.

I figure it's a ground loop issue.

Need to wait until I get the new volume control installed first to see if that takes care of the problem.

If not I can use these transformers to go from balanced to unbalanced.

https://www.edcorusa.com/xsm15k15k

I've used those transformers before and the smaller WSM series and they always sounded good to my ears.

I know there's an active device that will do what I need, but that requires circuitry and a +/- power supply.

If I cannot solve the ground loop any other way I may order a pair and try them on the output of the sound card as there's no hum at all with the Sony just connected to the crossover.