Oscilloscope for bass guitarist

May 31, 2017 12:28 PM

I would like to buy an oscilloscope ("analog", if possible - the LED screen ones do NOT have the aesthetic I am looking for) and use it as part of my bass guitar rig. Yes, this is just because I think it would look cool. Um. What is it I am looking for? How would I connect it?
posted by dirtdirt to Technology (6 answers total)

Just buy any old 'working' CRT oscilloscope off of ebay (doesn't have to be a very 'fast' one in the Mhz range), and hack together a 'probe' connection (probably BNC on the scope end, and 1/4" on the other). It's really simple, if you've ever had to make a patch cable - you could even use alligator clips and bare wire if you don't want to solder.

If your amp has a 'headphone/line out' jack, it'll be easier, otherwise you may need some sort of splitter.
posted by destructive cactus at 12:41 PM on May 31, 2017 [3 favorites]

An oscilloscope plots voltage(y axis) vs time(x axis). The oscilloscope will take a BNC connector to one, two, or 4 inputs. I suggest buying a cheap old scope off craigslist if possible, ebay if not, and verify that it turns on and you can see an input from a channel. You should be able to find one for less than 50 bucks. Ask the seller to throw in a bnc cable or two if they have them, they will most likely be male on both ends.

The cable will be coaxial meaning that it will have a central conductor and an outer shield. Cut off one end and attach both the signal whatever you want to look at and the outer ground braid to the signal's ground. If you have an auxiliary output with a mono plug you could use a cable like this to attach directly between.

After you have the signal you want routed to an input channel on the o-scope, mess with the voltage/div and time/division until it looks like you want.
posted by Quack at 12:46 PM on May 31, 2017 [3 favorites]

Find a "Hamfest" in your area - this is a swap meet for amateur radio enthusiasts. Someone there will be selling an o'scope for cheap, and if you ask them how to make it go, they will talk at you forever, and you will leaving knowing all the things. (Hams are, by definition, friendly helpful people).
posted by AliceBlue at 2:07 PM on May 31, 2017 [6 favorites]

Best answer: You should be able to find one for less than 50 bucks

Check your MeMail -- you may find one for free.
posted by bradf at 2:48 PM on May 31, 2017 [4 favorites]

If you want to get specific, Tektronix makes/made audio-specific scopes called audio monitors. Some demo footage here (youtube) though it mostly focuses on music created specifically to generate images on the screen. They (seem to) work largely the same as a regular oscilloscope but have controls that are maybe a bit easier to understand for audio use.
posted by mrg at 5:28 PM on May 31, 2017 [5 favorites]

Response by poster: Well, so: the best answer to this question can only be "be lucky enough to live in the same city as the pathologically generous Bradf and he'll just GIVE you a super cool old Telequipment oscilloscope."

Now to modify one of the cables he gave me to connect it to my rig. Thanks!
posted by dirtdirt at 8:33 PM on June 4, 2017