Recording

Audacity Help Forum Windows
1

if I record from the tape out jack of my preamp (Krell KRC), the signal, as shown on the computer screen, is tiny - 1-2 db with really loud passages up to 5db.
if I record from the output of a Tandberg cassette deck (which provides input and output gain controls), I get a more healthy signal

There’s a conflict between these two maxims:
Use the short route from signal to recording
Have a strong enough signal so the background noise isn’t as prominent.

what’s the consensus? Weak signal from the preamp or stronger signal from the tape deck/
using Windows 7, 64 bit, Audacity v 2.0.3 via installer

thanks

2

I’m a little confused by your dB scale… On the “digital side” 0dBFS (zero decibels full-scale) is the “maximum” beyond which digital-to-analog converters , analog-to-digital converts, and integer file formats (distort). That means you normally don’t see positive dB numbers… Only negative numbers where larger negative numbers are “more quiet”. I think by default, 0dB is shown as 1.0 (i.e. 100%) in Audacity, and the dB scale is optional.

I assume you are connected to your soundcard’s line-input (not a mic input)?

Line level (i.e. tape in/out) is not completely standardized in consumer equipment. Usually it’s around 1V, but I wouldn’t be surprised to find a 6db (factor of two) difference between different equipment. Usually, there is enough signal at the output, and enough gain at the input to get full power out of an amp with the voume turned-up when you mix & match equipment. Of course, a volume control will make a difference inthe signal/voltage level.

There’s a conflict between these two maxims:
Use the short route from signal to recording
Have a strong enough signal so the background noise isn’t as prominent.

You want a strong signal-to-noise ratio, but not a signal that’s so loud it clips. And, it’s always best to avoid attenuating a signal and then re-amplyfing it later because even the best amplification stages add some noise.

Most regular soundcards do not have an analog gain-adjustment. That means that it’s best to adjust the analog signal for peaks around -3 or -6dB (if possible) because you do want a strong signal-to-noise ratio, but you don’t want to risk clipping your ADC (analog-to-digital converer). if you are clipping the ADC, reducing the recording gain in your recording software won’t prevent clipping.

So in your case, I’d connect the “hotter” tape machine output to the computer instead of the using the preamp output. And, adjust it so that it doesn’t clip.

A low recording level isn’t always terrible… Pros often record at -18dB using low-noise computer audio interfaces (instead of a “soundcard”), and they record 24-bits. But, that is too low for most 16-bit consumer soundcards/soundchips.