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Ian Bell[_2_] Ian Bell[_2_] is offline
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Default Low Noise Sound card

Dirk Bruere at NeoPax wrote:
On 15/03/2010 10:03, Ian Bell wrote:
Mr.T wrote:
"Arny Krueger" wrote in message
...
Arny I'm really surprised I have to spell it out for you,
a passive analog attenuator reduces both signal AND noise
at *it's output* (amplifier input)
Of course, but read what I wrote: it does nothing to reduce the
noise at
the
output of the amplifier which is often the weakest link.

Read what I wrote, I never said it did. But the OP thinks his
amplifier is
not the problem.


The OP *wasn't*
complaining about his amplifiers noise!
In this case he had an amplifier with atypically low noise.

So why bring up something irelevant to the actual discussion then?


IF that was his problem, asking for a low noise sound
card is even more stupid!

The problem of coming up with an audio interface with dynamic range and
SNR
108 dB was solved long ago.

Never in dispute.


****, it's a pretty woeful amplifier that only gets 80dB
S/N these days! Hardly "audiophile" quality!!!!
Look at the spec sheets for some modern integrated amps.

Yep, "audiophile" grade pretty much around 100dB these days.
Your definition of "audiophile" grade may differ of course.


I'm here to tell you that many power amps that spec 100 dB are a
little
optimistic.

Sure, and many that aren't, and I've measured quite a few.


For a tube amp perhaps, but power amps with over 100dB
S/N are easily obtained these days.
They can be obtained, but 100 dB is not a low mark, especially if you
test
them on the bench.

Also consider that most CD players are attached to integrated amps, not
power amps.

Irrelevant to the current discussion. You are free to make a completely
separate point of course, but don't drag me into it.


Like I said, the OPs specific problem is in my views resolved days ago.

Years ago in fact, but he doesn't seem to realise it.

MrT.




And both of you please stop using s/n when you mean dynamic range - they
are not the same thing not to mention simply quoting a totally
unqualified dB figure is quite meaningless.


s/n as in max voltage output with an input of 0dB to the voltage output
with no input signal.



LOL, that's is awful.

0dB has no meaning.
Input termination in both cases is unspecified
Output termination is unspecified.
No bandwidth is specified.
No weighting or not is specified.
No mention of whether the measurements are rms, peak, quasi-peak
etc

Variations in the way the above are specified can make a large
difference to the 'measured' value and I bet you can guess which set the
marketing department will want to choose.

Cheers

ian

Cheers

Ian