Assymetric Waveform

[nowhereman579]

Hi there,
I got a '07 four string stingray one week ago and it is just GREAT !

But, when I try to record myself thru any audio interface I can see a very strange signal:

here is a closer look of the waveform:

On those pictures, the waveform goes way lower ("A" point) than it goes higher ("B" point). the A point is further from the ZERO line.

I've never seen such a strange waveform, that's I'm wondering if I have a serious issue with my bass guitar ?

Here is how look the wiring of my hambucker:

here is the electronic part so that you can identify the model:

Of course I've tried to put a new battery. Same result.
I also tried to remove completely the battery and ... same result but the signal is not centered the other way (B point goes higher than the A point)

Another clue: When I touch the plots of the pickup (the one that's is on the bridge side) with a screwdriver without touching the strings, it buzzes more than if I touch the plots of the pickup which is on the neck side.

Is this assymetrical signal a normal behaviour for a stingray or do I have bring my guitar to a musicman expert ? (Where in Lyon, France ?)
Thank you very much for your precious help

Regards,
Fred

 

[oli@bass]

I often get that. Also with other basses. I always thought that it was somehow down to how I pluck the strings...

 

[Colin]

without looking at the waveform, how does it sound to you?

 

[guenter]

Hi there,
I got a '07 four string stingray one week ago and it is just GREAT !

[...]

I've never seen such a strange waveform, that's I'm wondering if I have a serious issue with my bass guitar ?

Welcome to the forum, Fred. Good to see more european recruitment here.

First of all: If your bass sounds good, i would not worry about the slightly unsymmetrical signal.

Possible reasons for this (only guessed):
1. Plucking direction? (up->down vs. down->up)
2. Alignment of the strings above the magnetic pole? If the center of the string is not exactly above the center of the pickup pole, this asymmetry can show up, because one side of the string will move more out of the magnetic field than the other one. If this happens with your E string, the G string should show the opposite behaviour (i.e. lower wave halves stronger than upper or vice versa).

 

[nowhereman579]

I come from a JB so it sounds ... massive
Well, on my amp, no buzz, much attack, rich of low-medium ... honnestly this sounded clean to me. But I wonder if that could be even better !!!
I'm afraid of early clipping when mixing with such a waveform ...
Do you guys observe the same phenomenon with your basses ?
Do I have to worry about it ?

@Olibass: I tried to play whith my fingers, with a pick, slap ... same result

 

[nowhereman579]

Hi Guenter,
this is interesting, I'll try to investigate tonight about what you're saying.
Yes, I think that poles are not aligned with strings but it would be the same for every StingRay I guess ?
I'll give a try by plucking the G-String and the E-String on their own and see what's happening about the waveform.
I'll also try to play upside down just to see if that inverts the offset.
Last idea: I may also try to lower the pickups in order to reduce the effect your talking about ?

So I guess I don't have to worry anymore about this ...
I'd really love to have a look on other stingrays waveforms just to compare ...

 

[guenter]

Hi Guenter,
this is interesting, I'll try to investigate tonight about what you're saying.
Yes, I think that poles are not aligned with strings but it would be the same for every StingRay I guess ?

Yes. I'd guess so.

I'll give a try by plucking the G-String and the E-String on their own and see what's happening about the waveform.
I'll also try to play upside down just to see if that inverts the offset.

Let us know what you find out.

Last idea: I may also try to lower the pickups in order to reduce the effect your talking about ?

No. Lowering the PU will only reduce the overall output. But the "+-" ratio should remain the same. You should probably check, if the PU height is set correctly at all. (You can check the factory settings here)

So I guess I don't have to worry anymore about this ...
I'd really love to have a look on other stingrays waveforms just to compare ...

What hardware/software did you use to record your bass?

 

[nowhereman579]

What hardware/software did you use to record your bass?

External M-Audio Firewire Solo into Ableton Live 7 LE. I had the same result when removing the external M-Audio and using the poor internal audio chipset in my computer.
The problem doesn't happen with the same Hardware/Software with other guitars such as my previous JB nor my Les Paul nor my Nighthawk.

The only noticeable difference I see between all these guitars and the SR4 is the EBMM's active electronic ? But even when I removed the battery and try to bypass (I 'm not really sure about that ???) the active preamp: same result except as I said, the waveform was inverted but still with the offset

The factory specifications for the pickup height is 6/32" or 4.76mm from the top of the plastic between the pickup covers to the bottom of the G string

I'll check this out because I think pickups are way higher than these settings ...

A last clue: I forgot to mention that I'm tuned two steps down (E string is a 0.115)

 

[smallequestrian]

Metal strings oscillating through a magnetic field is not a symmetrical system!

 

[Psycho Ward]

I'm just a bass player.

 

[DTG]

I'm just a bass player.

Class dude very very funny! 

 

[danny-79]

I'm just a bass player.

Me to !
Just got my intonation issues sorted out, not that it was an issue just me being to picky.
Thats some deep deep deep detail your going into there

 

[adouglas]

Gee, and I thought Asymmetric Waveform was the name of a band....

Once I got to meet Dr. Amar Bose. As in, yeah, that Bose...noise-cancelling headsets, Wave radios and all that.

He gave this really interesting talk that explained the Bose philosophy and why they don't quote enough specs to keep the tech-heads happy.

While fascinating, compelling and full of great anecdotes, the details are unimportant here.

The bottom line is this: The purpose of any system is to produce a desired result. If the result is what you're looking for, how the system achieves it is not important.*

Therefore, since the bass sounds great, what's going inside it is not of any concern.


*Note that I used this same principle in this message. You don't need to know what he actually said to get the point, right?

 

[mmbassplayer]

His Stingray is alive with a nice heathly heartbeat. JOSH

 

[Holdsg]

I find the same thing on some of the keyboard forums I am on. The guys that gush incessantly over oscillators, envelopes, and LFOs, I just say "huh?". If I can plug it in, hit a note, and it sounds good to my ears, I'm good.

 

[Jimmyb]

Ignore the waveform.

No instrument is sinusoidal (except something that's a sine wave generator) the closest natural instrument you'll get to a sine wave is a flute, even that changes dependent on pitch and playing method etc.

Metal strings oscillating through a magnetic field is not a symmetrical system!

 

[danny-79]

If it sounds good to my ears then its job done.

If it sounds good to others peoples ears than its MORE than job done.

But when i start arguing with gadgets that are questioning my ear (an i believe it), i just have to remind myself that even thought all this technology that we have at our hands is good.... its still reference only.

 

[Aussie Mark]

That waveform must really make it difficult to measure sustain times.

 

[oli@bass]

Ignore the waveform.

No instrument is sinusoidal (except something that's a sine wave generator) the closest natural instrument you'll get to a sine wave is a flute, even that changes dependent on pitch and playing method etc.

The point is not that the waveform isn't sinusoidal, that's logical otherwise it wouldn't sound like a StingRay. The interesting thing is that it isn't symetric. I wonder whether that may be a charactersitic of parallel wired pickups (keko, and hints on that?). I have to compare recordings of my 25th in parallel and serial modes...


BTW, I find these more scientifically approached topics very interesting and don't understand why so many have to chime in and tell the OP to not care about some interesting sonical or electronical fact, or even make absurd fun of the topic. If you're not interested or don't want to learn, keep it to yourselves.

 

[keko]

Could be anything ...I remember when I was recording my first amateur video clip for this forum purpose, I had some kind of "chorus" effect in the background and for a long time I couldn't detect what went wrong?

Later, I discovered that amp head was to close to DVR recorder and that added some electromagnetic influence into the record...etc. (I haven't heard that when playing, 'cause monitoring was my bass box!

After that, all home amateur recordings I do with professional headphones!

You never know what may invade into the pickup electromagnetic field!

Check the whole recording "chain"!