Horrible distortion when recording 12" singles

[pat marcus]

Dear All

Second post and hope someone can help me on this one, too.

Im using a Technics sl1210 as a source with a top-of-the-range ortofon nightclub mk2 cartridge into my little poject phono box 2 usb.
Whilst albums are fine, with 12" singles the signal is heavily overloading the input so that the metres are permanently in the bad area and there's loads of clipping going on. This is particularly bad when using the line-in solution and while it isnt so audible with usb, the level indicators are all still showing masses of distortion. Can i somehow "turn down" the input more than it already is...........which is 0.0 ?

[waxcylinder]

The underlying problem here is that 12" singles were/are recorded "louder" than their 7" equivalents or LP tracks. There is basically more vinyl real-estate for the recording engineers to exploit.

Are you using an external USB soundcard to connect the Project pre-amp to the computer? Or are you plugging direct to the line-in on the computer.

If you are using USB soundcard then this may be the root of the problem for you - in that when a USB device is plugged in, Audacity hands control over to the USB device and disables the Audacity input slider (Mic icon).
Edit: I just looked more closely at the specs and I see that the Project box that you have does indeed have a USB output - which also means that it has it's own onboard "soundcard" (ADC - Analogue to Digital Converter). For your 12" singles you could try plugging from the RCA ouputs of the Project box direct into the line-in on your computer (assuming that you are not using a laptop, where line-in ports are rarely fitted).

It is unfortunate that the pre-amp that you have does not have a gain control on it (a couple on the market do, including the ART DJ-PreII that I use). Apart from that it's a nice looking pre-amp from looking at its specs.

WC

[pat marcus]

Thanks so much for the quick response. I think I havent been clear enough in my description.

Ive tried both ways. With the USB route there is no audible distortion but the meters are constantly in the red and the the wave shown in the main panel is almost obliterated by red (which I guess is indicative of overload?)

When I go "line in" and have disabled the usb functions, the problem is much much worse. I can hear the sound distorting horribly as it plays back out through the soundcard. When I record it is equally distorted.
I understand that 12"s are pressed much louder than albums. Is there a way of turning down the sensitivity of the line in outside of audacity to get round the problem ? If for instance I turn down the line in level in my soundcard control panel, would this help or does that only affect the output ?

I quite agree that a phono stage/preamp with a gain control would solve the problem...........

[waxcylinder]

Is there a way of turning down the sensitivity of the line in outside of audacity to get round the problem ? If for instance I turn down the line in level in my soundcard control panel, would this help or does that only affect the output ?

I certainly would give this a try - but it will only work at all if you are going in via the line-in not the USB input.

I quite agree that a phono stage/preamp with a gain control would solve the problem...........

And unfortunately this costs more money..... - But it may be possible to source, or build if you are electronically competent, an attenuator to choke down the signal - I seem to remember similar solutions discussed previously on other threads in the forum, worth a search in the forum ....

WC

[pat marcus]

Cheers. Will try tonight and report back

[kozikowski]

Disks aren't that much louder. You have something else wrong.

Your cartridge is a high-output (almost certainly) moving magnet cartridge. If the switch on the back of your preamp is set to moving coil (MC) the resulting output voltage boost will drive the system nuts.

Exercise the switch a couple of times to make sure it's not dirty or badly connecting.

Koz

[mikeymike]

hi guys, i actually have the exact same problem.

pro-ject phono box II usb is set to moving magnet (brand new out of the box), i have a ortofon scratch cartridge on a technics SL1200 turntable. USB signal is very hot and causes clipping. i have tried line-out recording and set the recording level lower on my soundcard, but it seems it's the actual signal coming out of the box that's already distorted (i can clearly see that the wav is distorted even when the line input level on my soundcard is down and most of the time you can actually hear it too).

pat marcus, rest assured you are not the only one with this problem.

i have contacted pro-ject who referred me to a service centre near me. when i got them to check it out, the result was that there is nothing wrong with the box itself.

unfortunately they gave me no solution on how to fix my problem.

kozikowski, i have tried your solution. it's definitely set to moving magnet because when i set it to moving coil the distortion is even worse.

any other ideas?

[steve]

Disks aren't that much louder. You have something else wrong.

Some 12" singles are very very hot - these are usually DJ disks and are designed for use in clubs on professional DJ decks with heavy tracking. I tried one (once) on my Thorens turntable, Ortofon (Hi-Fi) cartridge, and took it off real quick before it shattered the stylus.

I presume that the disk itself is in good condition? Have you played it on another deck and got a good sound? If so, record from that deck - the "line in" connection of a sound card should be able to cope with the line out of a phono pre-amp - if it doesn't then the sound card could be faulty.

Note also that there are different "standards" for "line level". Domestic equipment uses a lower signal level for "line level" than some professional equipment, so they are not always compatible.
(Consumer audio is typically −10 dBV, whereas pro audio is typically +4 dBu)

@pat marcus
It sounds like your "top-of-the-range ortofon nightclub mk2 cartridge" is kicking out too much for the "little poject phono box 2 usb" to cope with when you are playing your 12" singles.
So you're into DJ stuff? do you have a DJ mixer? That will have a volume control on it. Use your DJ deck, into the DJ mixer, then into the Line In of your sound card (make sure it really is a Line in not a Mic in).

If for instance I turn down the line in level in my soundcard control panel, would this help or does that only affect the output ?

There will be separate controls for input and output.

[mikeymike]

yes modern recordings are louder, but the problem is not the disk, it's the fact that the phono box MK2 has changed since the previous version and this one amplifies by 40db, where as the old MK1 only did 32db. (also i would add that another problem is the complete lack of volume control)

anyway, after getting hardly any help from local service agent (aside from him telling me the box is fine, which it is), i decided to take matters into my own hands.

thanks to some careful googling, i concocted a home-made DIY volume knob. essentially, a 10K dual-ganged potentiometer hooked up to a stereo RCA socket, and a stereo RCA lead cable. bingo! you can now control the input signal strength from your turntable before going into the phono box. no more clipping and distortion.. and all you need is a soldering iron and a few bits and pieces from your local DIY electronics outlet (radio shack, etc..)

here is a photo:

the RCA sockets are where i plug in the turntable, though it still needs to be grounded via the phono box. the rca plugs then go into the phono box, and you can see the potentiometer sticking out next to the sockets for volume control.

things you will need:
- 1 x 10K dual ganged potentiometer
- 2 x stereo RCA sockets (or 1 stere RCA cable + 1 stereo RCA socket like you can see on mine)
- some decent line cable
- a box to fit it all in (optional but looks nice)
and a soldering iron of course

hook it all up accordingly (the potentiometer needs to be wired up so as to make it a volume knob) -- plenty of websites are around that will explain how to do this, but if you like i can draw you a diagram.

$6 and half an hour later, you'll be laughing all the way home.

on the other hand, you could just try find an old model phono box MK1 and i think that would work a lot better for you seeing as it doesn't amplify the signal as much.

good luck!

So you're into DJ stuff? do you have a DJ mixer? That will have a volume control on it. Use your DJ deck, into the DJ mixer, then into the Line In of your sound card (make sure it really is a Line in not a Mic in).

yes but i think the point is to bypass the mixer, thus maximising the quality of the recording. for example my dj mixer is almost 10 years old, worn out, and hisses a lot, so if i can bypass the mixer for recording my vinyl on to PC i am a happy man.

[ouddingen]

I have a similar problem with an Audio Technica AT-PL50 turntable with a built-in preamp. Even with line-in set to 2, I still get some clipping. Mikeymike, I would be very interested in the diagram you offered for your DIY volume knob -- or links to the websites with more explanation of how to build one.