my analog input generates distortion ...

AndrewTurner · Post by **AndrewTurner** » Sun Oct 05, 2003 10:48 pm

I did the following test and noticed that there was distortion generated on a clean signal. I plugged my gibson guitar directly into the my classic 20 analog input , both Left and Right , by passing my pre-amp. I monitored the signal through Scope only and shutdown cubase in the tests. To monitor the signal I connected the analog inputs to a 2448 mixer and connected the analog out to the mix out of the desk. I am using a gigabyte mainboard with a VIA KT400 chipset with XP Pro.

Has anyone else experienced this. I am concerned that my inputs are damaged or faulty.

Mr Arkadin · Post by **Mr Arkadin** » Mon Oct 06, 2003 5:33 am

i think you may have committed an impedance faux pas here. Guitars don't work at line level. You would get shit results if you plugged a mic directly into Pulsar without a preamp too - it's not a reasonable test of the analogue inputs. A synth with a simple sine wave would be a better test as the impedance would match (or at least be close). If you only have guitars then pluging your guitar into a quality DI box should give a better idea of what's happening.

<font size=-1>[ This Message was edited by: Mr Arkadin on 2003-10-06 06:39 ]</font>

AndrewTurner · Post by **AndrewTurner** » Mon Oct 06, 2003 8:26 am

Thanks Arkadin, I get he same result when I plug into my Line 6 pod pro and connect to the line level output. I wanted to elimante everything in the path, cable, desk etc...

The distortion is only happens when the signal is decaying, roughly 500 ms after the signal is present. It then goes and comes back. The level of the distortion is affected by the volume level of the signal.

Post by **garyb** » Mon Oct 06, 2003 12:03 pm

that sounds like hardware....

darkrezin · Post by **darkrezin** » Mon Oct 06, 2003 1:10 pm

Maybe this is a silly question but have you checked with another set of cables?

peace

EarlyFirst · Post by **EarlyFirst** » Mon Oct 06, 2003 1:41 pm

sounds strange it only happens 500 ms later

cya
PT
currently listening to:
X-Dream - Rewind

Post by **garyb** » Mon Oct 06, 2003 10:15 pm

good point earlyfirst.andrewturner,check that there is no way that you have routed a loop...

krizrox · Post by **krizrox** » Tue Oct 07, 2003 8:19 am

I agree about the cables. Check to make sure the entire signal path is electrically sound first. Even new cables can be defective. Don't take that for granted.

There's nothing wrong (per se) with plugging your electric guitar right into a mixer channel input. It won't have the same full, rich sound but is perfectly acceptable. As mentioned, better to run through a direct box first. The Pod is an excellent direct box.

If all this fails to resolve the problem, check your guitar. Try a different one and see if you get the same results. Check your ground connections. Do you get the same results through the ADAT inputs? Do you hear this through the headphone connection in the Pod (not attached to the PC)?

One other thing I just thought of:

Does this little delay you speak of only happen when you pluck certain strings? Are you sure your guitar is set up properly? No string buzzing at the frets, nut or saddles?

<font size=-1>[ This Message was edited by: krizrox on 2003-10-07 09:22 ]</font>

bassdude · Post by **bassdude** » Tue Oct 07, 2003 6:23 pm

Have you tried another source to compare?
e.g. plug a cd player or something in to see if it distorts as well?

emzee · Post by **emzee** » Tue Oct 07, 2003 6:32 pm

Another thought....have you fitted active pickups......if so, have you tried a fresh battery..?