Max input level of a PC soundcard?

[krw]

Isn't that a mountian range?

A province of Pakistan, at least this week (India has other ideas).

Why should I go there? It's probably a nice
vacation spot but kind of far away.

I doubt it. It's one of the last places on my vacation wish list.
Actually, my vacation wish list is short enough not to have Kashmir
show up (by a long shot).

 

[Joerg]

Joerg wrote:




That is another sad story with the mass production stuff. If you publish
any technical data, it means they can sue you for being non compliant to
it. This is called "Deliberate misinformation of the customers". If
there is a big bucks behind the product, there will certainly be many
scoundrels who will try to do that.




An average Joe - customer can not understand anything about the specs.
So why bother publishing?




A galvanic coupling to the PC chassis may be a problem. There is a
ground loop going through the neutral of the PC power supply.

That's why I have a set of audio transformers here. Some days when I
want to be extra good I'll build a diff-amp. But maybe I don't want to
be extra good ....

 

[Vladimir Vassilevsky]

That's why I have a set of audio transformers here. Some days when I
want to be extra good I'll build a diff-amp. But maybe I don't want to
be extra good ....

You betcha. Jensen is the real thing. Don't trust to those silicon
roaches and spiders. Just don't connect the transformer to the power
rails

BTW I have a gathered test disk of music which is proven to be tough for
the audio systems. This is just a pop music. You never guess by the
sound how hard it actually is for audio system.

Vladimir Vassilevsky

DSP and Mixed Signal Design Consultant

http://www.abvolt.com

 

[Eeyore]

[email protected] says...

A province of Pakistan, at least this week (India has other ideas).


I doubt it. It's one of the last places on my vacation wish list.
Actually, my vacation wish list is short enough not to have Kashmir
show up (by a long shot).

OTOH, a Chicken Kashmir is an excellent (mild and rich) curry.

Graham

 

[Rich Grise]

Mine too but the silly thing has some kind of amp or limiter on the
line level input BEFORE the software level control meaning there is
_nothing_ you can do about higher input levels except to put a
hardware pot before the input to the computer. On this Gigabyte board
the bad stuff happens around lowish levels of only 3 V p-p. Danged
annoying - and dumb.

3Vpp is more than the "standard" "line" level I've always heard - either
1VRMS or 0.7VRMS; 1VRMS is only 2.828Vpp, so I'd expect 3Vpp to clip.

Good Luck!
Rich

 

[Rich Grise]

I checked it out, plus a few of the links. I couldn't find a simple
spec like the clipping level. At a bare minimum, input impedance
should be specified as well.

Line in is standard line level:
http://en.wikipedia.org/wiki/Line_level
That's for line in and line out, which is probably where you plug your
amplified speakers - the mic is somebody else's purview. ;-)

Hope This Helps!
Rich

 

[Eeyore]

3Vpp is more than the "standard" "line" level I've always heard - either
1VRMS or 0.7VRMS; 1VRMS is only 2.828Vpp, so I'd expect 3Vpp to clip.

" Line levels " are very nominal. The peak voltage normally exceeds the average
(as measured on a classic VU meter for example) quite considerably. By which I
don't mean the ratio of peak to rms value but the peak voltage taking into
account the dynamics of the signal.

That's why Teac / Tascam introduced the -10dBV operating level about 30 yrs ago
for lower cost 'semi-pro' gear, so it could run on fewer supply volts than truly
pro gear demanded.

Graham

 

[Eeyore]

Line in is standard line level:
http://en.wikipedia.org/wiki/Line_level

So which one ?

" Consumer audio equipment line levels are........ -10.00 dBV " or "
Professional audio equipment line levels are......... about 1.228 V " ?


Graham

 

[Joerg]

You betcha. Jensen is the real thing. Don't trust to those silicon
roaches and spiders. Just don't connect the transformer to the power
rails

BTW I have a gathered test disk of music which is proven to be tough for
the audio systems. This is just a pop music. You never guess by the
sound how hard it actually is for audio system.

All the kids with the gussied up cars play that kind of music all the
time, and very loud. Rap music. Tchk, tchk, BOOM, tchk, tchk, BOOM. Some
of them can make the walls of a house rattle when they drive by. You
know, the cars with barely an inch of ground clearance, shiny colors,
tinted windows and a fat "throaty" exhaust. Often followed by a police
car ....

 

[martin griffith]

Vladimir Vassilevsky wrote:


That's why I have a set of audio transformers here. Some days when I
want to be extra good I'll build a diff-amp. But maybe I don't want to
be extra good ....

http://es.geocities.com/mart_in_medina/zero-Z-tranny.pdf

fig 8.36 etc


martin

 

[Vladimir Vassilevsky]

All the kids with the gussied up cars play that kind of music all the
time, and very loud. Rap music. Tchk, tchk, BOOM, tchk, tchk, BOOM.

Fortunately, very few of compositions have BOOMs and TCHKs in the right
phase and sequence to put a maximum stress.

Some
of them can make the walls of a house rattle when they drive by. You
know, the cars with barely an inch of ground clearance, shiny colors,
tinted windows and a fat "throaty" exhaust. Often followed by a police
car ....

When you hear something like that, it can very well be my design

Vladimir Vassilevsky
DSP and Mixed Signal Consultant
www.abvolt.com

 

[Spurious Response]

No it isn't.



Incorrect usage. That's dB 'mu' btw not dBu. Furthermore it should be suffixed with a unit like V or W.

Absolutely incorrect. That is a lower case U.

It stands for decibels unloaded. And no, it does not also require a
suffix.

 

[Spurious Response]

No. It's merely the FCC that's wrong.

Graham

No, it fucking YOU that is wrong yet again.

 

[Spurious Response]

So which one ?

" Consumer audio equipment line levels are........ -10.00 dBV " or "
Professional audio equipment line levels are......... about 1.228 V " ?


Graham

Looks to me like the consumer design is more forgiving of abusive,
overdriving idiots.

http://www.sizes.com/units/decibel.htm

 

[Spurious Response]

Fortunately, very few of compositions have BOOMs and TCHKs in the right
phase and sequence to put a maximum stress.


When you hear something like that, it can very well be my design

Most are Class D setups.

 

[Eeyore]

Absolutely incorrect.

I'm absolutely correct.

That is a lower case U.

The FCC document contains references to dB *mu* (as in micro) not dBu.

It stands for decibels unloaded. And no, it does not also require a
suffix.

The FCC document is not referring to " decibels unloaded ", a voltage reference. Read the document in the link.

e.g. " field strengths along the protected contours are 0.5 mV/m (54 dB?) and 0.7 mV/m (57 dB?), respectively."

Where ? is the charcter 'mu'.

Graham

 

[Eeyore]

No, it fucking YOU that is wrong yet again.

READ THE BLOODY DOCUMENT IN THE LINK YOU UTTER FUCKWIT.

DON'T YOU KNOW THE DIFFERENCE BETWEEN THE LETTER 'u' AND 'mu' ????

Graham

 

[Eeyore]

Looks to me like the consumer design is more forgiving of abusive,
overdriving idiots.

http://www.sizes.com/units/decibel.htm

No it isn't.

Consumer 'line level' inputs are more easily overdriven than professional ones.

Graham

 

[Spurious Response]

I'm absolutely correct.

No. You are an idiot. There is NO measurement in electronics OR audio
that uses dB and mu without a qualifier.

This is a WELL known industry term. It refers to an unloaded or
unterminated line, and the term is dB unloaded, or dBu.

You couldn't be more fucking wrong.

The FCC document contains references to dB *mu* (as in micro) not dBu.

WTF is "The FCC Document"? Cite?

The FCC document is not referring to " decibels unloaded ", a voltage reference. Read the document in the link.

The term referred to in the wiki link is as I stated.

decibels UNLOADED.

From the SAME wiki link (if you had actually taken the time to examine
it):

http://www.sengpielaudio.com/calculator-volt.htm

http://www.mmproductions.co.uk/faqgen5.html

http://www.sizes.com/units/decibel.htm

ALL refer to it correctly as dBu. No LATIN characters are anywhere is
sight.

e.g. " field strengths along the protected contours are 0.5 mV/m (54 dB?) and 0.7 mV/m (57 dB?), respectively."

Where ? is the charcter 'mu'.

Graham

Dude. You are lost.

 

[Spurious Response]

READ THE BLOODY DOCUMENT IN THE LINK YOU UTTER FUCKWIT.

DON'T YOU KNOW THE DIFFERENCE BETWEEN THE LETTER 'u' AND 'mu' ????

**** the document, you fucking idiot. Don't you know the difference
between your pedantic bullshit and what this thread is actually
discussing?

The dBu that is being referred to in this thread IS decibels unloaded,
and THAT IS ALWAYS expressed as dbu and there is NO Latin character used
in the term. Never was... never will be.

So whatever fucking term you have focused in on, in your little
meanderings around the world, is NOT the term we are discussing here.


So you can back the **** up, and start over any time now.