Audio Testing Software

[supro66]

Has anbody used this for checking Tube Guitar amps

Audio Testing Software
http://cgi.ebay.com/Audio-Testing-Software-Signal-Generator-NEW_W0QQitemZ110503567240QQcmdZViewItemQQptZBI_Signal_Sources?hash=item19ba869f88

Can you get a real AC sine wave from it

[Heinz]

There are several free programs that do the trick, no need to spend money. I have used siggen when I started building amps.
Use your favorite search engine and look for "signal generator soundcard".

These are just some examples:
http://www.techmind.org/audio/#siggen
http://heliso.tripod.com/download/generator/dsg.htm

However, keep in mind that messing with tube amps is potentially dangerous for your PC. Connecting your sound card to the wrong spot can kill your entire PC. Using an old spare PC for the workbench is probably a good a idea.

[FYL]

Has anbody used this for checking Tube Guitar amps

Nope. Why pay for an approximate thingie while there are hundreds of high quality free programs?

[supro66]

I am still don't know how a computer with 101000100010001001010

can make a pure AC sine wave

See I got this nice Scope off someone on these threads

I wat to inject a 1/4 volt AC wave into the input of the amp 12AX7

and see it travel to the out put tube 6L6

[FYL]

I am still don't know how a computer with 101000100010001001010
can make a pure AC sine wave

Not 100% pure: a sine wave is infinite in length. But a 16-bit digital version is good enough...

[HotBluePlates]

I am still don't know how a computer with 101000100010001001010

can make a pure AC sine wave

The same way a CD or DVD does, close enough, anyway.

The digits represent instantaneous amplitude, as if you were measuring the ac wave with a dc meter, and noting the reading maybbe 48,000 times a second (sometimes more). That of course assumes your dc meter (and you) actually responded that fast.

Digital audio is a humongous number of discrete amplitude steps, taken at a fast enough rate to approximate analog signals. How good the approximation is depends on a lot of things and is debatable.