i've just bought ssl and have managed to play mp3's as vinyl successfully on the right side of my mixer, but can't seem to get the left channel to work... vinly wont register the tranck, and it plays in reverse!!?? i've made sure that the l and r channels are round the right way. also tryin to figure out how to switch from ssl format to playing with normal vinyl.... help.

Just read the manual carefully and go by it step by step....

?

check again your L and R channel connections. reverse play is a result of reverse L / R channel input.

sometimes, old ttables have their L / R RCA connections reversed, check it.

about question 2, please read user manual :P

What do you mean with "vinly wont register the tranck"?

Sometimes the headshells are wired wrong, so left and right side are reversed. Have you tried simply swapping the left/right rca cables?

As bartaug said, read the manual, there is even a picture how you have to wire all cables. STICK to that manual, and follow exactly the descriptions.

check the tone arm weight...

Also, check the setup screen. You should see a green circle when you play the record, if it is a straight line, then one channel is not working. Some turntables have loose wiring, and one channel is completely gone. Trying swapping the headshell from the other turntable and see if that fixes it, if so your headshell is not wired correctly.

i would never have guessed...is this true?

if so, would swapping the RCA's going in to the SSL interface yield the same results?

Try and see :-) It is the same concept as a rotary encoder (endless knob) or
film sprocket machine.

bartaug, can you explain a little more... I though SSL listens for the 1kHz tone, then adjusts the signal so it knows the pitch and then looks for the noisemap print? I cant imagine right know why reversing l/r makes it go backwards.

There are two 1kHz tones (L and R), 90 degrees out of phase. This is also what you see in the setup screen, it is called a Lissajous Figure. When you look at the two waveforms you can tell the direction and the speed. This is called Biphase Encoding, it is used to synchronize film machines from the early days on and probably also used in a mouse (with ball). As far as I understand is the noisemap used to find where you are at the record and the biphase for the speed and direction.

I think that one of the reasons SSL has such good scratch performance is that the speed/direction is encoded seperate from the position information. That makes a much faster speed/direction encoding possible.

Bartaug is correct on all counts. And FYI, the same kind of biphase encoding is indeed used in a ball mouse, except instead of two signals, they use two detectors, arranged quarter of a wavelength apart. We use a single detector (the needle) and two signals (left and right channel).

And yes, if you reverse the left and right RCA connectors, your songs play in reverse, however needle dropping won't work, because the noisemap will be backwards.

bartaug, thanks for the explenation. Another question:

Why does SSL need both signals? And why does it compute the direction and speed from the phase of both signals? Wouldnt it be enough just to pitch the signal to 1kHz, and then you got the noisemap, with that noisemap, you exactly know at what postion you are. If you know the previous position then you know the speed.

Because the noisemap is not accurate enough.

The noisemap gives you a position to the nearest millisecond of vinyl, and it is not always possible to read position from the noise map - for example if you place the needle on the record and wiggle it a few millimetres back and forth.

With the biphase signal, we can compute the relative movement in tiny fractions of a millisecond instead of whole milliseconds. Without it, scratching would not be possible.

good to know, I'll try not to be drunk the next time I connect the SSL interface at a gig...so I don't kcuf tihs up...

Guys, I must admit I am a tech geek and also a passionate dj. This whole stuff really fascinates me. If anyone got more info how that control signal thing works, dont hesitate and post it... PLEASE :-)

How does the way SSL works differs from the way Final Scratch works when it comes to the control signal/timecode/detection of the movement etc.?

And... I hope you SSL guys put a patent on the whole noisemap thing!

The FS vinyl works exactly the same way when it comes to the biphase signal - one channel leads the other by 90 degrees, which gives them the same speed/direction system. The problem with the FS signal is that the amplitude modulation is so extreme that it distorts the clarity of the biphase signal. In other words, they sacrificed smooth movements for a louder timecode.

To see the problem that this causes, try loading a pure tone into FS, I used a 4kHz. Then listen to how that tone sounds when you play it with the vinyl or when you press the play button (internal mode). The tone sounds dirty, which is harmonic distortion caused by an overpowering timecode in their signal.


I don't believe in patents any more. They are anti-competitive and the system favours large corporations with loads of money. Originally, the patent system was designed to protect inventors and foster innovation (by making inventions public domain) but these days, patents are more likely to stifle innovation. I would rather see the whole patent system abolished.

You mean the overpowering of the timecode makes FS not to recognize the timecode correctly and then makes the played sound distorded? What does the internal mode have to do with it?

I think AJ means the timecode makes FS detect the speed badly, causing high frequency modulations of the audio played

That's a good test, I will demonstrate it to some friends with FS. Wanna guess what they going to buy afterwards?

Thats a good belief. Along these same lines, what about a feature, such as a switch that would reverse the L/R signal and play the mp3 backwards, such as the reverse button on the newer Vestax TT's?

couldnt you just record your music backwards?

this could be done in software (in relative mode of course) but would anyone use it?

(: .kcalb wen eht si sdrawkcab , nosaes siht esuaceB

lol

YES!!!!

me and a friend of mine "discovered" this few months ago. FS causes armonic distortion!!!! when you play a tone with FS, it suddenly and quickly changes pitch following a time pattern.

this is TERRIBLE when playing tracks with chords, solos, pianos...

this is why FS = CRAP.

BTW, we founded SSL has similar problem, BUT 4 OR 5 TIMES LESS!

still hesitating about buying SSL of FS? ;)

whoa... similar problem? can you give some more detail on that?

To be fair, there is an option somewhere in the preferences of FS called smoothness, and I never tried it - I imagine it averages the detected velocity over time, but I imagine that would turn your scratching into mud, otherwise it wouldn't need to be an option.

I play a lot of trance, and I noticed (in my brief dabble with FS) that long string sounds during breaks sound terrible. Just as you describe - flutter and modulation on the sound.

BassChamber, yes, I also did some testings where I had a constant sine tone, and I experienced those "harmonic" distortion (I am wondering why these are called harmonic?) but I did this test when the pitch drift issue was hurting us. I will do the same when the new vinyls are out, and we will see if SSL still has that problem.

But compared to FS thats like nothing. SSL has a very good sound compared to FS.

Because these frequencies are a multiple (==harmonic) of the original frequency.

How comes that these distortions are multiples of the original frequency? That does not make sense to me.

With this definition, I have to say, that I didnt recognize harmonic distortion, but "normal" distortion. I used a 5kHz signal, and the frequency range I got was much broader. Anyway, I hope this problem will be resolved with the new vinyls, and that it was due to the bad control signal pressing.

Did increasing the buffer size affect this distortion at all Nik39?

Josh, buffer size was at 20. If you dont know where the results are, you can send me an email.

BTW, we all still cant see your eMail address.

you are right nick, i didnt repeat the "constant tone experiment" using pitch drifting compensation...

i will have to check it.

as i said, playing a constant tone with SSL you can notice some small tone variations every 6 - 8 seconds. but this is nothing compared to FS. FS armonic distortion is waaaaay larger (every 2 seconds).

and i didnt check this setting buffer to minimum... thats interesting!

bartaug, you wrote



How does that work?

Does anyone know what base frequency tone FS uses?

AJ, arent you scared that if you reveal what is wrong with FS's timecode, ... that you help them? Or is this trivial?

You can draw two sines/squares with a 90 degree phase shift on paper and go back/forwards over them with a vertical ruler. Then you can see how you can get direction/speed out of this.


It sounds like 1 kHz to me.


I guess if your technologie is way ahead doesn't matter :-)

I like helping people. Traditionally, by the time our competition catches up to us, we've already moved on to better things.