PlanetZ forums - scopeusers.com

My speakers are humming like crazy. I've checked all connections, made sure there are no feedback loops. Im going in via passive DI with the ground in place, lifted is worse. Bypassing cuts the noise completly. So is it supposed to add so much noise? It raises up four leds on scope mixers.

Tried going in via mackie xlr to analog in and beringer xlr to adat. I don't have noise problems with other fx only dynatube.

Ok it's iumproved somewhat goin thru adat and takingf all gain pots low externally and amplifying internally, and paying close attention to gain and master controls on dynatube. Wish I didn't have to deal with external signals at all, none of this noise rubbish with scope synths thru dynatube.

Isn't it inherent to compressors and distortion effects to amplify noise levels?

You need to watch your gain-staging.

guitar -> (DI -> mic-preamp) -> AD/

The only really "noisy" model imo is the fender. But I actually think it's realistic.

As I said Atom I've not had this problem with other devices and thats with either vocal or guitar (without DI up untill recently). But yes your right voider , that gain staging has to be watched carefully. I don't know if this is the case for real world guitar rigs but in my case the amount of wiring and connections (unbalanced) has probably got alot to do with it.

A real amplifier has one or more high impedance inputs for best matching with the guitars' pickups.

You would need to substitute this environment in a computer setup for best S/N-ratio. Depending on what kind of interfacing you have you can either just plug the guitar straight in or through a DI+Pre-amp-stage.

A passive DI is not the best for musical instruments. You would have better luck with an active DI. Even then a guitar pre-amp then AD is best.

a preamp of some kind is required. it must have a hiz input, either in it's design or from a di box. i prefer a good mic pre.

Thanks everyone for your input and help. I've got myself an active DI now and the difference is amazing! The guitar now sounds bright and clear with plenty of crunch
Going thru active di--> mic pre--> adat in.

a good example for the effect of 'damping' the guitar by relatively low input impedance
A budget solution could be the M-Audio AudioBuddy (80 bucks), which has 2 mic/instrument inputs and both symmetric/asymetric line outs plus phantom power for condesor mics.

For guitar and vocal it's exceptionally good (considering it's price), but strangely it seems to lack definition for bass.
I was very sceptical about the latter statement (which I had read from a reviewer on the net), but it's exactly what happened with my instruments, too - and I would have much appreciated the 'pure' bass on the 2nd line.

the specs don't reflect this at all, so eventually one depends on one's ears - as usual...

cheers, Tom

pff, M-Audio suck of cheep crap.

are you certain you could pick the crappy box from 30 audiofiles in a blind test ?
It was the cheapest candidate in a big micpre-shootout, but by far not the worst performer

cheers, Tom

maybe I wouldn't be able to tell the difference (especially in a mix)

It's quite a funny subject though, because many guitarists have plugged their $1000 geetars into cheap crap for eons & just thrashed over the top of the hiss & crackles