noise floor of pulsar1

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Havoc
Posts: 81
Joined: Fri Aug 03, 2001 4:00 pm

Post by Havoc »

Used the analog in for the first time. I connected nothing except the breakout cable. Then made a recording (24/44.1) of 30sec and looked at the noise floor. It is somewhere around -112dB, but both left and right have a single tone peak. Left at 19950Hz, right at 20500Hz, sticking out to -102dB.

Now this is not audible, but I don't have it with an external convertor (that I will not be able to use). Is this noise induced by the PC (then why are L and R different?), or do all pulsars have it? I tried moving slots and cables in the pc, but no change.
subhuman
Posts: 2573
Joined: Thu Mar 29, 2001 4:00 pm
Location: Galaxy Inside

Post by subhuman »

I noticed <i>significant</i> noise when I used unshielded RCA cables. Changing the cables, and plugging the mixer/computer/monitors into the same grounded outlet solved it, nearly silent.
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astroman
Posts: 8455
Joined: Fri Feb 08, 2002 4:00 pm
Location: Germany

Post by astroman »

your values are ok, mine are far worse, about -60 dB and audible. In my case the Pulsar is mounted 90 degree wise on a riser card just above the MoBo - so there is induction of noise. I'm absolutely sure about this because the noise could be reduced significantly by inserting a metallic part between Pulsar and MoBo.
Btw measuring the open input may be misleading, as Ingo from Creamware pointed out in their forum once. Sorry I don't remember the details, maybe something like terminating a network device.

<font size=-1>[ This Message was edited by: astroman on 2002-03-05 13:59 ]</font>
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