Complete newbie here

I’m a complete rube at this. I do not understand any of the jargon. It’s like trying to read Chinese.

My boyfriend gave me a huge box of old cassette tapes to transfer to digital. Some of them date from the 70s. I’ve got his old tape/CD player plugged into my iMac desktop and downloaded Audacity. I’ve got it to record but you can hear all ambient noise: TV, me talking to myself, etc. Tried muting microphone in Mac Preferences and Audio MIDI Setup, but it won’t record without the mic picking up everything.

Am I going to have to buy some other piece of equipment to get this done?

This set of tutorials from the Audacity Manual should help you:
https://manual.audacityteam.org/man/tutorial_copying_tapes_lps_or_minidiscs_to_cd.html

WC

plugged into my iMac desktop

Step one it has to be old enough to have an actual stereo analog connection like this two arrows and circle.

If you do, then it’s a simple matter of setting Audacity to record from that connection. If you don’t, or you have an unmarked connection or one labeled as headset, then it’s harder.

Koz

Which iMac? Go to Apple menu > About this Mac and tell us what the first line says.
– Bill

Screen Shot 2020-11-23 at 7.44.10 AM.png

You are in luck. The mid-2010 iMac has a stereo line-in jack.

Audio
Built-in stereo speakers
Two internal 17-watt high-efficiency amplifiers
Headphone/optical digital audio output (minijack)
Audio line in/optical digital audio input (minijack)
Built-in microphone
Support for Apple iPhone headset with microphone

Go to Apple menu > System Preferences > Sound > Input and you should see an option for “Line In” or similar. Select that.

Connect the line outputs of the cassette deck to the line input jack of the iMac using a dual-RCA-to-miniplug cable. This page in the manual shows you how to do that.

Leaving the System Preferences window open, play a cassette and make sure the bouncing sound meter shows that you are getting sound into the iMac.

In Audacity, in the Device Toolbar, make sure that “Line Input” (or whatever it is called) is selected in the Device Toolbar as the Recording Device.

Audacity 2.4.2 does not officially support macOS Sierra. If it works for you, good. If not let us know and we’ll direct you to a place to get an older version.

– Bill

Will not record at all with “Built-in Input” selected.

Only records with “Built-in Microphone” selected.

And then it picks up all background sounds - TV, people talking, etc.

Did you go through the steps in my previous response?

Go to Apple menu > System Preferences > Sound > Input and you should see an option for “Line In” or similar. Select that.

Connect the line outputs of the cassette deck to the line input jack of the iMac using a dual-RCA-to-miniplug cable.

Leaving the System Preferences window open, play a cassette and make sure the bouncing sound meter shows that you are getting sound into the iMac.

What do you mean “will not record at all”? Do you get a flat-line recording, or is it that the recording cursor does not move?

– Bill

Yes, I did.

Recording cursor moves but does not record.
input.jpg
input .jpg

Your cable is plugged into the auxiliary input of the cassette deck. Looking at the specs of this unit it appears it does not have an auxiliary output. You could connect a cable from the headphone output to the input of the iMac.

– Bill

Same result. Cursor moves but no recording.

Plug headphones into the cassette player. Play a tape and adjust the volume. Unplug the headphones and plug in the cable to the iMac.

Go to System Preferences > Sound > Input, select the Line Input and make sure the sound meter is bouncing. If not, find out why.

– Bill

OK. Right now I have a male-to-male cable plugged into the cassette player and the iMac. So I unplugged that completely.

I plugged headphones into the cassette player, checked the volume level, but then I got confused. Do I plug the headphone jack into the iMac? But then the computer is not connected to the cassette player.

How will I hear the tape playing without anything being plugged into the cassette player?

Confirm that you are getting sound out of the cassette deck by listening with headphones. Unplug the headphones from the cassette deck, but leave the cassette running.

Plug the male-to-male cable from the headphone output of the cassette deck into the Line Input of the iMac.

Go to System Preferences > Sound > Input, select the Line Input choice and confirm that the sound meter is bouncing. If not, find out why.

If the sound meter is working in System Preferences > Sound > Input, start Audacity.

In the Device Toolbar select “Line Input” for the Recording Device and “Built-in Output” (or “Headphone jack” or “speakers” or whatever - there will probably be only one choice) for the Playback Device.

Go to the Transport Menu and make sure Transport Options > Software Playthrough is checked. This will allow you to hear the cassette while you are recording.

Click on the recording meter where it says “Click here to Start Monitoring”. You should be able to hear the cassette playing through the iMac speakers.

– Bill

OK that finally worked!

Very helpful.

I know you have to go to incredibly stupid detail for beginners, so thanks for that.

You’re welcome. Glad we got it sorted out.
– Bill

I am a new register user but unable to find how to post an issue/topic for set up of Mac Big Sur. I know I am in the wrong spot/forum. I am totally frustrated at this point.

To start a new topic, go to the “macOS” forum page: macOS - Audacity Forum
then click the “New Topic” button.

Installation on Big Sur is the same as for Catalina. See: Audacity ® | Download for Mac OS