DP24 hiss in recordings

[rawbar]

My teen daughter does voiceovers and found our DAW too tricky to work with so I picked up a refurb DP24 which is much simpler for her.

It's a very simple one track setup with a Rode NT1 (new version) inside a small sound deadened room. All effects off. Mic gain is set to about 9:00 (ie maybe 20% up), but somewhere I'm picking up a hiss. It's audible in the headphones when monitoring (Beyerdynamic DT770s) and when the recorded audio is moved to a PC/Mac for editing. I have phantom power on but as far as I can tell, everything else is clean.

I've been googling and have tried resetting to factory settings (per Phil Tipping) and I'm not sure what else to try given this is such a basic setup.

Note I'm not an audio engineer by any means, I'm a tech guy that's good at getting myself in over my head though. I'm stumped what to look at next. Any suggestions would be greatly appreciated.

 

[-mjk-]

Hi @rawbar and welcome to the Tascam Forums. The DP headphone amps are known for having background noise that is not acceptable to some, but is not actually on the recording. Are you saying that the background hiss is the same level on the recording file?

Just a thought - what are you using for monitoring on the DP-24 and the computer? Have you tried listening to the audio file completely outside your studio environment?

You can try using some of the other inputs and see if there is a difference. Also, remember that if you happen to be using input H, make sure that "guitar" switch is turned off. It probably is, but it's worth mentioning.

If you get stuck, you can put a sample in a cloud folder and I'll take a look at the noise profile and see if we can't figure out what it is.

 

[Eric Guicherit]

Like MJ says, the headphone amp has a noticeable hiss which through my Beyerdynamic 990 is quite a nuisance. It's more pronounced when turning up the reverb available in the guitar effects so that one I never use. This hiss is not recorded (so it doesn't appear through my monitors) but depending on the effects you use you will keep hearing it through the headphone amps.
In the mean time I got used to it but in the beginning I thought my recorder was faulty.

 

[rawbar]

Thanks all, it's my wife that's working with the audio file and is telling me there's a hiss. She says she's been removing the hiss in audacity with a filter but sent me a copy of the unedited file. Let me take a listen, or really more of a look at the waveform and see if I can visually see the hiss she says is there.

 

[rawbar]

Looks pretty quiet to me, if anything it looks like I need to turn up the mic gain. I had it turned down so low to limit the hiss but I don't see anything. The wife is wearing headphones plugged into a Mac, maybe the onboard mac audio output is noisy?

Thinking about it further, perhaps the audio on this clip is so low, she probably had to crank up the mac volume which would almost certainly introduce distortion of some sort (perhaps in the form of hiss?)

 

[-mjk-]

Thinking about it further, perhaps the audio on this clip is so low, she probably had to crank up the mac volume which would almost certainly introduce distortion of some sort (perhaps in the form of hiss?)

That is a distinct possibility. Even in the digital domain they're is a noise floor. On the DP machine you'll want to record nominally between -15 and -12 dBFS. Playing back a quiet track will reveal any shortcomings of the amplifier.