Why the hiss??

[Keith_H]

We record with a tascam mkii 4 track and then i mix it down to a wave file with goldwave so that i can make mp3's. But there is this hiss that's very noticeable in the wave file--why is it there? And when i encode an mp3 the hiss turns to a "gurgle" sound.

Reasons I've thought of:
I have an old soundcard - sound blaster 16 i think - really old..
cheap radio shack wires going from 1/8" to 2 rca's..

Any ideas?
Keith

 

[JimH]

Do you think it's tape hiss? When you play back with just the tascam 4-track and listen to it with headphones, do you hear the same hiss? If so, then it's tape hiss. I'm not familiar with the tascam, but if it has noise reduction, don't forget to use it to reduce the hiss.
Although older sound cards can sound bad, I don't think they normally introduce hiss but rather some other type of noise. I think the gurgle in the mp3 is happening because hiss (noise) is hard to compress. The compressor cannot encode hiss very accurately so it becomes a gurgle. As an experiment, you can choose a higher quality mp3 compression and it might start to sound more like hiss.
If the cables were the problem, I think you'd hear a buzz, not hiss.

Jim

 

[Keith_H]

I know it's not tape hiss because it sounds great on the headphones or running out of my stereo, it's just when the .wav file is played back. Another thing- say I play a CD on my computer and record part of it into goldwave, it does it there too, in fact one time I recorded "nothing" -just silence and played it back and there was a hiss...weird.

I agree with the gurgle theory, I have some free encoder called bladeenc that i don't really even know how to set the parameters.I'll get a better encoder or learn that one better after i solve this hiss mystery.

Keith

 

[JimH]

If you record nothing (no cables attached) and still get hiss, then I gotta think that narrows it down to the sound card. You might make sure that the record level on the sound card was set to a reasonable level. I mean if your record level was very high and consequently you set the output level of the tape very low, you might get hiss there. But I guess that's not likely. (When I said that older sound cards don't normally hiss, I guess I wasn't completely correct. I was thinking more along the lines of the A/D conversion not being good. But if the signal/noise ratio is bad, then you'd get hiss.)

I assume you're recording the CD through the input of the sound card as opposed to ripping it directly off the CD. If you rip it off the CD, then no way should you get any hiss in the wav.

Other than that, I don't know. I defer to the more knowledgeable.

Jim