Noise on optical recording

Hy all,
I’m using macOS 11.1 and audacity version 2.3.3.
I’m using a quite old Yamaha DCR-HD1500 recorder, where I have stored several songs on it’s internal HD which I recoded from some old vinyls. I now want to transfer those songs onto my Laptop using the optical Toslink output of the recorder. Therefore I’m using a Toslink to USB converter (USBStreamer from miniDSP). When I connect the converter to the Laptop over USB, I can select the device as input and start recording. So far so good.

My problem is, that the recorded sound has a lot of noise and is very unclear. I don’t understand where this is coming from, since in my understanding there is no digital to analog conversion in this path, since Toslink and USB are both fully digital signals. I tested a bunch of different settings about the sampling rate and so on but I always ended up with very unclear sound. Does anyone may have a idea where the problem might be?

Thanks very much in advance!

Let’s see if the problem is with Audacity or elsewhere.

You should have “QuickTime Player” in your Applications. Start it up. From the File menu choose “New Audio Recording”. Click the Record button and record a few seconds from your Yahama. Stop and play it back. How does it sound?

– Bill

Hy Bill,

Thanks for your input. I tried it today and it sounds the exact same way. So it looks like that it’s not really a problem in Audacity, but more in the hardware.

Thanks anyway.

You could record from the analog outputs but you’d need a digital interface such as the Behringer UCA-202 or similar.
– Bill

As a practical matter, digital-to-analog-to-digital conversion is usually transparent so an interface with line inputs (such as the UCA 202) should be fine. If fact it should be better, given the problems you’re having. :wink:

But before you go that way…
Are you sure the Toslink output is OK? Do you have a Toslink input on your stereo, etc?
Are you sure the analog output is OK?
If all of that is OK, you might check with MiniDSP support or ask for help on their forum.

Listen to the headphone output of the recorder.

– Bill

Hi guys etc. I am a new user with Audacity.
I have a similar query with regard to noise using USB link from my new TEAC USB record deck( belt driven) to IMAC ( High Sierra 10.13.6)
Whilst the noise cannot be heard on the finished recording I am perplexed as why this is occurring. Let me explain, if I click Start to Monitoring, but before lowering the stylus, or starting the turntable to rotate, the monitoring level meter shows a noise of -36 dbs. If I then turn off the power to the turntable this noise subsides. (Turntable is not rotating at any time but power is supplied to motor, even though not rotating )
I assume motor hum ( even though stationary ) is being picked up by some wiring and passed to the USB connection to the computer.
Is this possibly a fault or maybe a design fault with the turntable, which is not a cheap one. Can I shield somehow to stop this, although the hum is not audible on the finished recording.
Any views before I query this with the manufacturer/ supplier of the unit would be welcome.

I have a similar query with regard to noise

You’ve got a different issue… You’ve got an analog problem - Noise is almost always an analog (or acoustic) problem.

It could be AC power line hum or a vibration from the motor. Phono cartridges are sensitive to electromagnetic pick-up as well as mechanical vibration and then the preamp amplifies the heck out of it!

Try recording some of the noise and then run Analyze → Plot Spectrum so you can “see” it. You may want to run the Amplify effect first. If it’s subsonic noise you can run a high-pass filter at 20 or 30 Hz to kill the noise with no effect on the signal. If it’s a higher frequency but in a narrow frequency range, you can try a notch filter. Or you can try the regular Noise Reduction effect.

I assume it’s a low frequency noise because you’d hear mid-band noise at -36dB. There’s also a possibility that it’s at the upper audio-frequency range but I wouldn’t expect that from a turntable… But, a USB turntable has high-frequency electronics inside and a possibly a switching power supply.

Just be careful with noise reduction because there can be artifacts/side effects and “the cure can be worse than the disease”, especially since you aren’t hearing the noise anyway.

So, since your Yamaha DCR-HD1500 recorder runs at 44.1kHz, make sure you have the same speed set in Audacity and on your USBStreamer.

I hope this helps. :smiley:

I once purchased a combination VCR/DVD/CD player that worked fine except when in CD mode it had terrible hum (over the same wires, go figure!) :confused: I returned it to the nearby big box store and got a replacement which had the same exact problem. Since I didn’t feel like going back to the store AGAIN, I took the recommendation of a clerk at an audio shop: I cut off the ground pin (shudder) and plugged it in via a ground-fault protection device so I would be safe from electrical shocks :exclamation: I don’t understand it today, but it corrected the hum. :astonished:

I suppose if I were in your situation, I might consider returning your “new TEAC USB record deck” and getting something similar but a different brand.

Good Luck! :smiley:

Good Afternoon to all, hope you are well, bright sunny day in N.East again today!
Thanks very much for your helpful comments. my hum on the TEAC may be more complex, since when I first switch on to start the days recording, there is NO hum. Later on in the day the hum seems to ‘appear’. I shall monitor it now obviously to see if it appears after a set time or similar.
I have already tried moving the mains cable and USB connections as far away from each other as possible but the fact that the hum appears to be intermittent is very strange, unless the TEAC motor develops a hum after being on for several hours.
I am going to see if the Phono output is affected in the same way at some point too.
I was aware that the TEAC did not have a ground earth socket, which I thought was unusual but I can probably fix one up to see if it helps!
I was going to buy the Audio Technica AT-LP5X Turntable but it was out of stock when I was buying!
Thanks for all your help anyway.