42-year-old tapes sound great on speakers before Audacity re

[rostkow]

42-year-old tapes sound great on speakers before Audacity recording;

I have a collection of mono 3-inch, reel-to-reel voice tapes made while I was stationed in Vietnam. I plan to edit and archive most on DVD’s with still photos from that era.

I have an AKAI X-1800SD reel-to-reel player set up to play only the left channel. The sound quality of these tapes from the device speaker is excellent. I have a six-ft audio cable (1-Mini Plug/2-RCA Plugs) connecting the device to my desktop computer line-in port (SoundMAX Digital Audio). The sound quality of the tapes from the desktop speakers through my sound card is excellent.

My problem is the poor quality of the Audacity-recorded sound when played back in Audacity. Playback of all of the recorded waveform has a harsh high-frequency distortion (no clipping). Enough so that it obscures many spoken words beyond recognition. I am using 44100 Hz, 16-bit sampling. I have tried setting the device volume high and the line-in volumes lower, and tried the opposite with no noticeable difference in the recorded playback.
The only thing that helps a little is to apply about 12 db of noise reduction and a special equalization curve. Considering the excellent quality of the source tapes, however, this is a poor solution. What else can be happening?

[kozikowski]

<<<My problem is the poor quality of the Audacity-recorded sound when played back in Audacity. >>>

But everything else played back in Audacity sounds fine?

The Audacity recordings sound OK played back somewhere else?

So you have Skype?

Do you regularly record internet audio?

Koz

[kozikowski]

I don't have extended music clips, but try to play the piano solo and the organ finale from here...

http://www.kozco.com/tech/soundtests.html

They should sound like a grand piano and a cathedral organ.

I will admit being attracted to the idea of solving a problem from someone who is making no obvious technical error.

Koz

[rostkow]

The audio clips that you provided sound fine played back in Audacity. So , the answer to your first question is: Yes, everything else played back on Audacity sounds fine.

For those "reel-to-reel" recorded waveforms that were exported to .mp3 there was no quality improvement if played on Nero., Microsoft Media Player, Quick Time, ATI multi-media center or CyberLink Power Director.

I do not have Skype.

I am not into recording audio from the internet.

Al

[kozikowski]

<<<I am not into recording audio from the internet.>>>

Oh, darn. Had you said yes to any of those things, we could get on with it.

What happens if you Export as Microsoft WAV format instead of MP3? Leave the Audacity preference settings at 44100, 16-bit, Stereo. The files will be enormous compared to the MP3 files, but the damage should vanish.

When you installed Audacity 1.3.x, did you also install the particular MP3 lame software that came with it? Audacity versions and lame travel in flocks these days and you may not cross them.

Koz

[rostkow]

I'm not sure that I ran a current copy of lame when I downloaded 1.3.x. I'll try that.

Before doing the WAV file, however, there is something about the appearance of the "raw" (undoctored) waveform being recorded as an .aup file that I am suspicious about. The waveform does not have any peaks beyond +.53db to -.53db. It looks very artificially cut off. Is there a way to send you a Prt Scr of that waveform? When I do the noise reduction and equalization, the waveform looks more like a natural voice pattern.

Al

[rostkow]

I answered my own question. Thanks, anyway.
It was all about volume control.
I set my reel-to-reel tape player left channel at mid-range. I set my SoundMAX computer volume line-in at one click from the lowest setting.
I set the Audacity line-in at one click from the lowest setting.
Recording was very low amplitude, but there was no distortion.
I amplified the track, did noise reduction and equalization and got the best results yet

Al

[kozikowski]

Barring anything being actually broken, are you sure you're plugged into the right connection in the sound card? That clipping at 0.5 thing is the signature of plugging a high level sound device into the Microphone Input of a sound card.

"It only works when I reduce the volume controls almost all the way down."
Second signature. It quacks like a duck......

You also need to know, if you don't already, that the computer speakers and Audacity recording pathway are different, have different circuits, and take different controls. More than one production has spent an hour listening to a show and produced a perfectly straight-line, silent sound file. That's why Audacity has both blue wave timelines and bouncing lights sound meter. If you don't get those perfectly correct indicators, you may have no or damaged show.

It's usually considered a bad idea to try and make a computer sound card do anything useful, but it's my opinion that once you get the system straightened out and running, they're not all that bad.

Koz

[rostkow]

Thanks,

I checked the soundcard inputs again. The device is plugged into the "blue" mini-plug. And, the device volume responds to the SoundMAX line-in volume control slider. I have my speakers plugged into an light green mini-plug and a microphone plugged into an orange mini-plug. This all corresponds to the schematics that came with the soundcard. I think that my Akai X-1800SD has an awesome amplifier and I wasn't prepared for the task at hand. I'm sure, now, that there are volume settings (three in my situation) that will record voice on Audacity very close to the original magnetic tapes.

Al

[Constantine]

Possibly, for even better results, set your sampling rate as high as your soundcard can handle (48Khz, 96Khz or 192Khz) - with a move to 24 bit / 32 bit floating resolution - then when you've finished the recording, export the file at your desired bit depth resolution and sampling frequency (44.1khz / 16bit for cd's - from the projects setting)