Hello, I would like to add a preamp out to my fender black face twin so as to connect it to a Macintosh, saw some links to how it’s done but all are broken links and have been taken down. I live in Alaska and know of no tech that could be hired to do this so need to do it myself. Would greatly appreciate if someone could direct me to a “how to” if one exists. Thanks.
These days we have more options than Jerry had, and for this application, I would suggest getting a Suhr RL or RL-IR reactive load box. It plugs into the output jack in place of the speakers, and gives you the line out to feed the Mac. It is a little different than Jerry did it, but you get the signal after the power section which has some benefits.
If for example, you want to get the late 60's Gibson into cranked Twin tone, you can crank the amp and get that creamy power section distortion he used in those days. Obviously, turn down the amp to clean it up for the 70's through 80's tones.
The IR version adds speaker emulation with IR's for use with headphones, or playing through monitors or a PA. Stuff you don't need to play through the Mac into JBL's, but may be of use to you for other things.