USB turntable - only one channel

[mikeprice]

Hi all

 

I have an old USB turntable which has never worked properly but I have decided to have a go at fixing it - again

 

Basically - it has 2 connections possible -

normal hifi outputs - red and white - this works fine showing that needle, etc etc etc all work OK

USB via a normal printer (etc etc) type connection - drivers load automatically in Windows

 

The problem is that when I try to record from it I only get the left channel - not the right

 

I have now tried it on several USB cables and 2 different PCs

I have also tried putting the input to the supplied software - can;t remember what it was - and now I'm using Audacity

always the same result

I have also tried every different setting on the device - all either don;t work at all - or work just fine - but left only

 

I have tried peering into the USB port and it all looks normal - and the cable works fine with my printer

 

Any ideas of anything I am missing before I try to take the thing apart and look for loose wires

 

It's one of those things - I should have taken it back to the shop when I first found the problem - but as that was 8 years ago I've probably left it too late!!!

[3s-gtech]

Well - you could just pipe the phono connections into the audio-in 3.5mm jack on the PC, then set Audacity to that input. Bypass the USB entirely - I guess it’s just a USB ‘sound card’ device driver so set the quality up high, use a decent codec and bitrate, and make sure there’s no earth hum or similar.

[mikeprice]

Well - you could just pipe the phono connections into the audio-in 3.5mm jack on the PC, then set Audacity to that input. Bypass the USB entirely - I guess it’s just a USB ‘sound card’ device driver so set the quality up high, use a decent codec and bitrate, and make sure there’s no earth hum or similar.

 

Thanks - yup - I could just put the audio jacks in - but I would like to get the USB thing working - just because

 

I have tried all the different bitrate and they all do the same thing - no apparent hums of anything

 

I think I will have to try taking it apart - no great loss as I have another turntable connected to my hifi - so if I screw it up I can use that

[3s-gtech]

Could be a number of causes, from a loose cable (seems unlikely given that the phonos are working) to a burned out channel in the analogue to digital converter or a dry solder joint. Doubt you’ll do any harm by having a poke around.

[chazzy2501]

Yeap, as stated above the usb is digital so all or nothing! The issue will be at the analogue side, on the DAC. As you have phono connectors it should be easy to trace and I suspect like the others a dry joint or a loose cable. Get a soldering iron and go for it!

[mikeprice]

Hmmm

 

the problem here is I am useless with a soldering iron - my hands have never been that steady

still - what could possibly go wrong!!!!

[southhamster]

Hmmm

 

the problem here is I am useless with a soldering iron - my hands have never been that steady

still - what could possibly go wrong!!!!

Ah. I love smell of burning flesh in the morning...

[jmak]

Thanks - yup - I could just put the audio jacks in - but I would like to get the USB thing working - just because

 

I have tried all the different bitrate and they all do the same thing - no apparent hums of anything

 

I think I will have to try taking it apart - no great loss as I have another turntable connected to my hifi - so if I screw it up I can use that

I get the "just because", but I reckon there's a good chance the DAC in your PC will be better than the DAC on the record deck...

[3s-gtech]

The sound card in your PC will have a better sampling rate I expect - the circuitry in the deck will be bargain basement (hence possibly why it failed). Don’t think it’ll be anything to do with a DAC as the source is analogue. Edited October 15, 2019 by 3s-gtech

[mikeprice]

OK - I've taken it apart and can;t see anything wonky or anything

As expected the insides are some heath-Robinson mechanical stuff to control the arm and a simple motor to spin the turntable

 

The electronics are a very small board leading to the USB socket

2 earth leads to the board via the screws that hold it in place

 

so I've put it all back together and it has made no difference

 

Think I'l just plug in in through the analog leads and see what happens

 

 

Thanks for all the suggestions