Why the preamp

A forum for topics related to the turntable/cartridge/stylus and the phono preamps used with MsPinky
Post Reply
Why the preamp

Post by fructose » Sun Nov 14, 2004 7:33 am

So what I dont understand is ... if the difference between line-level and phono level is that phono is softer is and has needs eq adjustment, why does that stuff need to be done at the hardware level? Why cant that be done as part of the software?
Joined:Thu Jun 10, 2004 10:57 am

Post by paulheu » Mon Nov 15, 2004 12:44 am

There is no reason why it can't. In fact some apps (like the excellent djDecks) do..
There are 10 types of people in this world: those who understand binary, and those who don't.

Post by Guest » Wed Mar 09, 2005 5:45 pm

paulheu wrote:There is no reason why it can't. In fact some apps (like the excellent djDecks) do..

is that true?

Developers, will there be a fix like this in the near future, so i could save

the cash for buying crappy preamps that i wont need for anything else....
Site Admin
Joined:Mon Jun 07, 2004 9:17 pm

depends on the quality of your audio converter

Post by dlpinkstah » Wed Mar 09, 2005 8:26 pm

In general, if you plug the output of a phono cartridge directly into the inputs of an analog-to-digital converter which expects to receive a line-level(1 V peak-to-peak) signal, what ends up getting inside your computer is a very noisey representation of the original signal from the turntable. If you amplify this noisey representation inside the computer, what you get is a LOUDER NOISIER digital representation. You do not solve the fundamental problem (weak signal) by just amplifying/EQ-ing in the digital domain because it's rather impossible once the signal is digitized to separate the desired signal from the noise. When you amplify digitally, you amplify the desired signal AND the noise simultaneously. It's just that simple.

However, if you use a fairly decent phono preamp, you are amplifying the desired signal above the noise before it gets digitized. So once inside the computer, the digital signal is LOUD and CLEAN, just the way it should be for ideal decoding of the MsPinky signal. This is why I recommend strongly the use of phono preamps.

However, whether or not you _really_ need to use phono preamps depends on the quality of your audio converter. For example, several users have reported that with the Digi-002 (which has built-in mic preamps) you can just plug the turntable directly into Digi and it works great. But that's partly because the Digi has the mic preamps, and partly because it has very high signal-to-noise ratio on its inputs. So because the Digi's inputs are so high resolution (24 bits, I think) you still have plenty of leftover SNR (signal-to-noise-ratio) such that you can just amplify in the digital domain and the MsPinky signal can still be reliably decoded. But because most audio converters are not of such high quality, I don't recommend this way of doing it. But you may get away with it anyway-- it just up to you if you want to risk not getting optimal performance.
Joined:Fri Sep 30, 2005 11:41 pm

RE: Why the Preamp

Post by bedhed3000 » Fri Sep 30, 2005 11:53 pm

You can avoid using a preamp if you use turntables with preamp built in. I use Audiotechinica ATPL120's. They are comparable to 1200's and they have a reverse mode.
Joined:Mon Jul 04, 2005 12:40 pm

I know that theoretically this is bad but hey.... it works

Post by TequilaKez » Mon May 29, 2006 11:31 am

Just to scrath an itch I tried plugging my turntable straight into the line in on my powerbook and grounded it to the mixer. Fired up Ableton and put a utility plug before the pinky pluggo to raise the level.

I have to be honest, there was probably a really high error metric but for all intensive purposes it didn't sound or feel any different when scratching than with the preamp.

Ofcourse this is not 'ideal' but it's handy to know if you get to a gig and your preamp screws up or something.

Infact, if you're after minimal setup and u afford to go mono, you can do a pretty cool set with just a lappy, one deck and a mixer.

Try the setup above, send your beats and what not to first channel of your mixer via the left side and pinky output to the right and scratch with crossfader as normal. Worked for me the other night when I left some of my shit ot home :)
Post Reply