Stromgeräusche bei Laptop eliminieren Einstellungen

[Derrick S]

Da anscheinend einige dieses Problem haben mit Laptop und USB Soundkarte, hier mal ein thread drüber

habe beim Novation Support (welchen ich mal ausdrücklich sehr loben muss für ausführliche und schnelle Hilfe am selben bzw. nächsten Tag!) mal angefragt was man tun kann

Although some companies now seem to be making more of an effort with built-in laptop audio quality, perhaps due to the number of their customers using laptops to play back audio CDs and DVDs, components will be packed more densely than in a desktop machine, internal shielding may be insufficient to prevent noises passing from one internal device to another and getting into the audio signal path, and you may get further digital noises due to the switching mode power supply, plus others that accompany mouse, drive, or graphic activity.

Having experienced soundchip interference problems, many musicians assume that they will be able to cure them by plugging in an external audio interface. Sadly, this doesn't always happen, since you are still relying to some extent on the regulation of the laptop's power supply. The vast majority of laptop power supplies are switched mode devices that have a two-wire mains connection on the input side. This means there's no direct earth connection, so the audio circuitry will be left 'floating'.

So, connecting your laptop's audio interface to a properly grounded mixer doesn't create a ground loop (there's still only one ground connection involved), but it's possible that its PSU may still introduce the background noises mentioned earlier. You can confirm this by unplugging the PSU and relying on battery power - if the noises disappear then you are probably suffering from problems directly caused by the PSU and the laptop's grounding design.

Even if you could, buying a ‘better' PSU probably won't solve the problem, but sometimes you can reduce or even eradicate it by plugging in a dummy cable to another port on the laptop (such as an unused serial or parallel port), and using the earth connection at the other end of this cable to connect the laptop's metalwork and ground plane to ground elsewhere, so you're not relying on the audio path to do it for you. However, you will have to be careful of creating ground loops if using this technique, and may have to break the earth connection in the audio cable, or make up a special lead with a 100 ohm resistor in series with the earth connection.

Very successful in many cases is connecting a passive (transformer) DI (Direct Injection) box between the laptop audio interface and your other audio gear to ensure total isolation, so that no unwanted earth current can flow in the audio ground connection. In this case we're not dealing with a ground loop problem, but the same solution may work. Make sure you use a high quality one, as many of the ‘ground loop eliminators' sold for in-car stereo use have a poor high frequency response and suffer from distortion at low frequencies.

[Derrick S]

(IMG:http://www.technoboard.at/style_emoticons/default/tounge.gif) problem mit Brummschleife gelöst, hatte noch ein Cinchkabel drannhängen am mixer welches diese verursachte...tja...auf die einfachsten sachen kommt man immer am schluss *gg*

[Derrick S]

hier noch ein Link sollte wer störgeräusche haben die durch das Speedstepping verursacht werden (prozessor rauf und runtertakten) kann rauschen oder ähnliches verursachen

http://www.diefer.de/speedswitchxp/

Der Beitrag wurde von derrick s. bearbeitet: 28 Oct 2006, 12:03