Reddit reviews PARTS EXPRESS XLR Female to 1/4" Male Line Matching Transformer

1. find a sturdy flat rubber washer that’s inner diameter is JUST enough to stretch over your strap button. The red ones from a Grolsch swing type bottle can work. Or, really any washer whose inner diameter is smaller than the outer button flange that you can install on top of the strap, unscrewing the button if needed. Even a plastic bread clip can work in a pinch, but a sturdy plastic clip like the Dunlop Ergo Lok or StewMac Lokstrap is a more sturdy no-mod solution.
   
   
2. You could get a reverb pedal like the TC Electronics Hall of Fame, but you need to be aware of the mic/line level difference, phantom power, and adapting to/from XLR to 1/4”. Edit:links.

http://www.amazon.com/gp/aw/d/B0002BF1KG
A good transformer will only run you 15.

If the acoustic has a pickup, just plug it in. For the mic, you can buy a mic cable with a 1/4 inch plug on the end. Make sure you get the cable with the female (the end that goes into the mic) plug. They make two different kinds, one with tip/sleeve (unbalanced) and tip/ring/sleeve (balanced). Either should work. Your best bet is to get a mic transformer that plugs into the end of the mic cable and converts to 1/4 inch plug. I used to use one all the time, way back when, to plug a mic directly into my old analog gear.
https://www.amazon.com/Female-Male-Line-Matching-Transformer/dp/B0002BF1KG

Just straight through as a piece of outboard gear. It sounds funny, but it works. I set up the cassette deck in record mode and leave it rolling (90 minute tapes), then stereo line in from the DAW and stereo line out back to the DAW. There will be a delay associated with this, so I usually find that I have to print it and manually align later. Another fun use for a cassette deck: colored mic preamps. Use a pair of these plugged directly into the 1/4" mic inputs of the cassette deck and run your XLRs to there.

Here's a typical inexpensive adapter that the previous poster mentions: XLR Female To 1/4" Male Line Matching Transformer

But you'd still probably need to custom wire a 1/4-female to 35mm connector to get it to work.