VinylRecorder Groove speed motor noise through record

[Dubcutz]

Hi David34

Mark is correct, i have the same issue with my VR so i placed a (Hum Destroyer) Behringher HD400 Between the last RCA Cable that Outputs to the Amplifier, Whine noise was gone after a silent cut was done.


Theo

[David34]

Thanks Theo! Ill look into this!

[David34]

Just bought a Behringher HD400.. Ill let you all know how i GO..

[sat159p1]

Hi,

He indicated that noise disappeared when he cut a silent groove with no electronics connected to the head. If that was correct, then its not mechanical noise due to the motor. Its electrical noise generated by the the motor. That should be able to be reduced or eliminated by careful attention to grounding, filtering, and/or shielding.

Mark

Mark, of course it will be gone without connecting cutterhead/motor to the VR (just opearting in manual by hand), because the noise it's the noise of the motor in the tube. It has nothing to do with rack units. Of course, maybe when shielding is bad, ground hum etc. but it's completely another case. This sound I heard on the recording was not hiss or ground hum. it was the motor itself (changin pitch due to speed changes), so if you want to get rid of it, rewind manual by hand (joking, of course). So, again, it's not in the signal patch and you will not eliminate it via any outboard gear unless you replace the motor (which is impossible).

I would like to hear samples when that Behringer is connected, also with varying recording speed, like on the sample provided. I guess that it will be still there.

[markrob]

Hi,

I think you are not understadning what I suggested. I never suggested not running the overhead motor. I suggested cutting a silent groove with no connection from the cutter head to the audio power amp. The idea was to run the overhead motor so that it could be determined if the noise was electrical or mechanical. Motor brush commutation noise will not be AC mains related. It will be related to the rotational speed of the motor. If the OP did what you are assuming, then I would suggest he re-do the test as I described.

Mark

[David34]

Hi guys I have cut a silent groove.

I had no audio source from cuttersmp (off) and the sound was completely gone..

Souri said it's earth loop I'm going to hope the behringer box fixes it!

I'll be in touch

[sat159p1]

If you lost the "motor speed change noise" when disconnecting power amp it's... a miracle.

[David34]

Hey guys just an update. The Behringer hum remover did not work. I still have a pitch sound that change with groove speed motor.

When I turn off cutter amp and cut silent groove - the pitch sound goes.

I will be working on a process of elimination today - starting by removing all the hardware units from the rack (as suggested by Souri)

I'll also take on board some of your very useful comments - I am really so grateful to all the trolls that replied and suggested solutions.

Stay tuned.. more to come.

[David34]

Ok.. Busy little day today. The things I have tried:

Plugged the whole rig into a different power outlet - no change
Bypassed my Behringer micro-amp - no change (this allows me to monitor levels and stereo signal via software back to iMac)
Removed main unit from the audio rack that I have all units in - no change (Souri recommended not to do this but it changed nothing)
Plugged the "Blue wave" Groove speed motor box into its own power outlet - no change
Bypassed my Furman M-10x E Conditioner - no change
Moved the earth lead from the cutter base plate to several other spots (including rack) - no change
Purchased a Behringer HD400 Hum destroyer, placed just before cutter amp - no change
Bypassed the small Mixer completely - iMac (audio out) > Main Unit > Cutteramp - no change

A friend is coming over with a 12v power supply to try and replace the "Blue Wave" Groove speed power supply. Fingers crossed.

Anyone got any other suggestions ??

[markrob]

Hi,

Why not start from the power amp and work backwards. Disconnect the inputs to the power amp and if possible, short the inputs. Keep all of the other equipment powered off. In fact, It might be best to remove everything from the rack and unplug the other devices so that the amp is the only thing in the chain. Do your testing and re-build the setup unit by unit to see if and when the noise appears.

Before you do all of the above, you might want to consider my earlier suggestion to connect speakers to the power amp rather than the cutterhead. You should be able to hear the noise via the speakers (maybe use headphones as they are more sensitive). If so, this will allow you to track down the source without having to resort to cutting after each change. If you can't hear the noise via speakers or headphones, I would be a bit skeptical about the noise being electrical. By monitoring this way, you eliminate mechanical coupling to the head as the source of the noise.

Mark

[David34]

Hi Mark,

I can hear the noise when I am not cutting.. In fact, when the mixer switch is on audio source (rather than pickup) it is quite prominent.

I have cut silent groove with cutter amp off. No pitch noise on record until I turn on the cutter amp, then it is on the record..

We are going to try a different 12v "Blue wave" box tomorrow. (Groove speed motor)

Will let you all know how we go.. Running out of things to check..

[markrob]

Hi,

For me the question still remains; if you have the power amp on with no audio inputs connected, is the noise still there? From your last statment, it sure sounds like the noise is being introduced early in the chain, givien the fact that you can hear it in the source mointor. Are you cutting from an analog or digital source?

Mark

[David34]

Hi Mark,

I have tried your suggestion of removing input leads into Cutter amp. The noise still remains.

This is my chain:

iMac (audio source) > Vinyl optimiser > thru Souri mixer > Main Unit (control groove speed here) > cutter amp > Cutterhead

When cutter amp is off, pitch sound still exists, but is not cut to vinyl, only when amp is turned on again.

Thanks Mark for your suggestion and help though!!

[markrob]

Hi,

I'm a bit confused. Is the sound you are hearing when the amp is turned off just the acoustical sound of the motor running? If so, you can ignore that, as it seems you have proven that this is not cut if the power amp is turned off. If I understand what you have discovered, the noise is present if the amp is on and no connections are made to the input of the amp. This pretty much narrows the problem down to the amp. What is the make and model of the amp? Did you try to short the inputs to see if the problem is related to the input stage? Have you tried a different power amp? Have you tried floating the AC ground with a 3 to 2 prong power adapter?

Mark

[David34]

Hi mark,

The noise attached is with everything on and cutting audio groove. When cutter amp is switched off, the pitch (groove speed motor) sound goes with it.

The cutter amp is standard VR - NJS760 (New Jersey Sound)

I'm sorry but I don't know what you mean by shorting the inputs to the amp? I have removed them from the back of the VR main unit and amp? Is that what you mean?

I haven't tried different amp as I don't have one..

Not sure what floating the AC means either mate. Will get my mate who is savvy with these things to explain..

I will try those extra suggestions tonight.. Appreciate your help..

Note - When I purchased the VR, it had European power plugs which I had to replace with Australian. Could this be a cause? If there were 2 x pins, they were replaced with two pins, 3 pins, then I replaced with the 3 pin Aussie version (hope this makes sense?) - COULD THIS BE THE ISSUE?? I wouldn't have thought so, but I am exhausting all possibilities!

[David34]

ps: The groove motor noise doesn't bother me, until it is cut into records audio - then it bothers me.

I'll be back later hopefully with results!

[David34]

OK Folks..

It is with great pleasure that I announce that we replaced the "Blue Wave" 12V Power supply to the Groove speed motor with another one and the pitch sound is ...

GONE!

I really hope this thread helps out any other VinylRecorder user out there that may have the same issues..

I would like to thank each and every one of you trolls that contributed with your suggestions - please know that I valued them and tried them all..

Love this forum.. I've learnt so much from you all.

[markrob]

Hi,

Great news! Glad you were able to track that down. It would be good to know why that supply caused the issue (e.g. bad grounding/shielding or filtering). Do you know if this noise was present from day one or did it develop later. That may provide a clue.

Mark

[David34]

I will check back on my old test cuts.

The funny thing is that the pitch whine was such a low frequency at 33 speed that I couldn't hear it.

Only when I cut 45 speed (70 on groove speed dial) did I hear the pitch as it was a high frequency and detectable.

We'll look into the box for anyone else on here who may have the same problems!

[David34]

Folks it looks like I counted my chicken before they hatched. ..

Ran a test cut this morning after assuming that the whine was gone (was not as audible when motor on with line selected)

but low and behold, the pitch sound was very prominent.

I'm honestly running out of ideas..