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Preamps overload very easily on 1818 ------->>> SOLVED! via Audiobox VSL 1.2 Driver
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MikeRivers
Presonoid
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Joined: 28/07/2010 15:44:52
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Rome wasn't redesigned in a day. It's only been six months now.

At least PreSonus seems to acknowledge that there's a problem and that it might have a solution that can be implemented without shipping all the units back to the factory for a hardware change.
Visit http://mikeriversaudio.wordpress.com for some useful audio info
"It's much easier to look for a magic solution than it is to adapt to reality." - Allan Sloan
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beachside
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Joined: 29/07/2010 00:29:21
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I have just re-tested with the just released software and can confirm, after 7 months plus, the clip inversion distortion is fixed. The minimum input gain has changed to -28dB, which is quite a change for the -15dB spec (measured -20dB previously), but not a bad thing. Unlike what others have said in other threads I have never had a problem with too little gain, only too much. If you need that much gain something is wrong with your gain structure.

Clip LED is to spec as before.

Seems like very little has been done to the VSL GUI unfortunately, but that's another story.

I also tested the USB3.0 'improved support' but found no improvement on 3.0 ports I tested. Still unusable.

This message was edited 2 times. Last update was at 09/06/2012 04:39:06

Focusrite 18i20. An '1818' that actually works as advertised and has great support!! But Presonus will continue the story it was all my systems and there is no hardware issue with the 1818 and the drivers are great.

Almost two years on and Presonus continues to say it's a 'top priority' but have no driver updates, make excuses and blame others (Intel, USB3 Microsoft, Apple and now the company that writes their drivers!) when other companies have it all working on the same systems!! And it so refreshing to get regular software updates and responsive and effective support!

And the 1818 does not have 'on-board DSP' as continues to be claimed.
bluesriff
Presonic

Joined: 26/01/2012 22:41:56
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Location: Los Angeles
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beachside wrote:I have just re-tested with the just released software and can confirm, after 7 months plus, the clip inversion distortion is fixed. The minimum input gain has changed to -28dB, which is quite a change for the -15dB spec (measured -20dB previously)....

Well, at least they fixed the worst of the worst offender...

This message was edited 1 time. Last update was at 09/06/2012 05:57:31

• MacBook Pro 15" 5,1 2.4Ghz (late 2008 unibody) Intel Core 2 Duo, 4GB RAM
• OSX Mavericks ~ 10.9.3

• AB1818VSL v1.2.2 Public Beta - Mac Build 1.41.0.5461 • Firmware 1.05
• Studio One Artist 2.6.2 Build 24770 OSX
~ All VSL related files expunged

SKB 2U (Shallow X Rack) • 2 x QSC K8 Powered Speakers • Shure Super 55 Mic • AKG C1000 Hypercardioid Condensor Mic • Mi-Si DUO Active 'Super-Capacitor' Soundhole Guitar Pickups • Shure SRH940 Headphones • iPad Air (forScore)
Monolithent
Supreme Baconator
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Joined: 28/07/2010 18:47:25
Messages: 13464
Location: Central New Jersey
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That's odd that your USB 3 isn't working...it's purring like a kitten on my system.

You're not on a Dell XPS laptop by chance? There have been some reports of bad usb3 ports on them. I'll see if I can get you some links if you fall into that category.

This message was edited 1 time. Last update was at 09/06/2012 04:56:23

http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
Win Vista 64/XP Pro/7 x86/7 x64 - Mac OSX Snow Leopard/Lion
Gigabyte motherboard--SYBA TI Firewire XIO2200A--i7 2600k Quad Core--16 GB DDR III--Custom 2U Rackmount--4 TB Raid (all internal SATA II)--19" Samsung HDMI LCD on pivoting VESA 1U Mount
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beachside
Presonic
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Joined: 29/07/2010 00:29:21
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Location: Melbourne, Australia
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Hmmm. I have a Dell, but not a XPS. Other 3.0 devices I tried work fine - have all the latest drivers etc. Anyway, that's not a big deal just yet.
Focusrite 18i20. An '1818' that actually works as advertised and has great support!! But Presonus will continue the story it was all my systems and there is no hardware issue with the 1818 and the drivers are great.

Almost two years on and Presonus continues to say it's a 'top priority' but have no driver updates, make excuses and blame others (Intel, USB3 Microsoft, Apple and now the company that writes their drivers!) when other companies have it all working on the same systems!! And it so refreshing to get regular software updates and responsive and effective support!

And the 1818 does not have 'on-board DSP' as continues to be claimed.
Monolithent
Supreme Baconator
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Joined: 28/07/2010 18:47:25
Messages: 13464
Location: Central New Jersey
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I'm using the wife's new i5 dell with no concerns so far. Lemme see if I can find some links. That might be able to be crossed by motherboard model or something.
http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
Win Vista 64/XP Pro/7 x86/7 x64 - Mac OSX Snow Leopard/Lion
Gigabyte motherboard--SYBA TI Firewire XIO2200A--i7 2600k Quad Core--16 GB DDR III--Custom 2U Rackmount--4 TB Raid (all internal SATA II)--19" Samsung HDMI LCD on pivoting VESA 1U Mount
Studio One v1 Pro x64
Studio One v1 Artist
Studio One v2 Artist
[Yahoo!]
MikeRivers
Presonoid
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Joined: 28/07/2010 15:44:52
Messages: 2247
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beachside wrote:I have just re-tested with the just released software and can confirm, after 7 months plus, the clip inversion distortion is fixed. The minimum input gain has changed to -28dB, which is quite a change for the -15dB spec (measured -20dB previously), but not a bad thing.


How are you measuring input gain? I remember when this discussion was fresh, someone went inside the box and looked at the output of the analog input stage. Was that you?

Since they can't change the analog gain without modifying the hardware, I assume that it's all OK through the A/D conversion, and what they did was attenuated the output of the A/D converter before it got to the VSL "brains." In theory this will cut into the resolution, but in practice, because of the inherent noise level making true 24 bit resolution impossible, there will be no degradation of performance.


Unlike what others have said in other threads I have never had a problem with too little gain, only too much. If you need that much gain something is wrong with your gain structure.


Not necessarily. I find a lot of modern interfaces are shy on gain when recording a quiet instrument. The amount of air it moves together with the sensitivity of the microphone determines how many millivolts you can get into the preamp. Moving the microphone closer changes what the mic "hears" which may not be desirable. And there aren't any really "high sensitivity" mics. Within about a 10 dB range, they all put out about the same voltage for a given SPL.

No, often I NEED all the gain I can get.

So have you measured the sensitivity at maximum gain? How many dBu in at max does it take to get to 0 dBFS? On the 44VSL, it's about -57 dBu and that's just marginal when working with acoustic instruments.

Visit http://mikeriversaudio.wordpress.com for some useful audio info
"It's much easier to look for a magic solution than it is to adapt to reality." - Allan Sloan
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beachside
Presonic
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Joined: 29/07/2010 00:29:21
Messages: 297
Location: Melbourne, Australia
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I measured the max gain at 59dB (the spec is 65dB). With the gain pot at max an input of -59dBu is required to hit 0dBFS. So very close to the 44VSL it appears.
Focusrite 18i20. An '1818' that actually works as advertised and has great support!! But Presonus will continue the story it was all my systems and there is no hardware issue with the 1818 and the drivers are great.

Almost two years on and Presonus continues to say it's a 'top priority' but have no driver updates, make excuses and blame others (Intel, USB3 Microsoft, Apple and now the company that writes their drivers!) when other companies have it all working on the same systems!! And it so refreshing to get regular software updates and responsive and effective support!

And the 1818 does not have 'on-board DSP' as continues to be claimed.
MikeRivers
Presonoid
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Joined: 28/07/2010 15:44:52
Messages: 2247
Offline

beachside wrote:I measured the max gain at 59dB (the spec is 65dB). With the gain pot at max an input of -59dBu is required to hit 0dBFS. So very close to the 44VSL it appears.


That's interesting. What you measured isn't really gain since you can't have a ratio of dBu to dBFS. I call it "input sensitivity" in my reviews and other writings. But perhaps the actual gain is 65 dB, then they attenuate the output by 6 dB and that's 59 dB. So if 0 dBu = 0 dBFS (no reason why it should, but just suppose) then there you go with your -59 dBu = 0 dBFS input sensitivity.

Anyway, if you can reach 0 dBFS without that nasty clipping, that's a good thing. Mission accomplished.

Got a male XLR connector and a 150 ohm resistor? Make up an input terminator, plug it in, and see what the noise level is at full gain. It'll probably be around -75 dBFS RMS.

Visit http://mikeriversaudio.wordpress.com for some useful audio info
"It's much easier to look for a magic solution than it is to adapt to reality." - Allan Sloan
[WWW]
 
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