Grounding issue with an odd setup

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CosmoQ
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Grounding issue with an odd setup

Post by CosmoQ » 01 Apr 2019 23:26

I have a Realistic LAB-420 (just got it - love it), that I have hooked up to my receiver and all is well as far as that goes (grounded properly with no issues). I like to rip my records via my laptop - but the 420's volume output, running to my laptop, is quite low and needs to be EQ'd something fierce. So, I attempted to serial it through a tube-pre-amp I had on hand, but am now having issues with even worse sound and humming. I tried running another ground wire, from the turntable, into a screw on the pre-amp's chassis. This causes humming like nothing is grounded at all. Grrrrr...

The turntable I was using previously had no need of grounding, as it seemed to have a built-in pre-amp, so I did not run into this issue (but this table was about as lame as one could possibly get).

As you can probably tell, I am an amateur when it comes to more complex sound setups and I could really use some suggestions.

My pre-amp is a ZhilaiAudio DZ (tube driven)

Thanks ahead of time for any suggestions.

kalaur
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Re: Grounding issue with an odd setup

Post by kalaur » 02 Apr 2019 05:47

If you want to digitize from the turntable, you need to run through a phono preamp first (the ZhilaiAudio D2 is only a preamp, *not* a phono preamp). This will amplify the levels and apply the RIAA correction so your ADC can capture the proper signal. If your receiver has a preamp *output* you can use that into your ADC/laptop. If your receiver does not have preamp outputs, you need to purchase an external phono preamp. There are many to choose from, let us know a budget and we can offer suggestions.

Grounding can often be tricky. Generally you want everything grounded together, but only one single ground path to one point (star style ground). However, this is often almost impossible to accomplish with most gear.
Start with grounding the table to the phono stage (whether its a separate phono stage, or in your preamp).

If after you acquire a phono preamp and have grounded your table to it you still have hum, let us know and we can continue troubleshooting.

jspink
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Re: Grounding issue with an odd setup

Post by jspink » 03 Apr 2019 18:06

If your receiver has a Tape Output, you should be able to use that also.

CosmoQ
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Re: Grounding issue with an odd setup

Post by CosmoQ » 07 Apr 2019 20:59

Soooo... since reading all of your valuable and appreciated advice, this has occurred; I tried using the "tape out" only to find that something is possibly burned out on my old Sony receiver, producing no sound through that method.

I have wound up defaulting with using the headphone jack, running it though my preamp to EQ out the sound a bit - as well as more subtle volume control).

I just need to buy myself a new and reliable receiver - which would make life much easier and predictable.

Thanks to everyone for such helpful information!

kalaur
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Re: Grounding issue with an odd setup

Post by kalaur » 07 Apr 2019 23:29

I will restate, your ZhilaiAudio D2 is NOT a phono preamp. You need to use some sort of phono preamp that will apply the RIAA eq curve to the output of the cartridge. Since you keep mentioning you need to 'EQ the sound', this leads me to suspect you are not using a proper phono stage, just a regular preamp.

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