-  [WT]  [PS]  [Home] [Manage]

Posting mode: Reply
  1.   (reply to 16401)
  2.   Help
  3. (for post and file deletion)
/sci/ - Science, Technology, Engineering, and Mathematics

Join us in IRC!

•This is not /b/ or /halp/. Tech support has its own board.
•If you are not contributing directly to a thread, sage your post.
•Keep the flaming at a minimum.
•Tripcodes⁄Namefags are not only tolerated here, they are encouraged.
•We are here to discuss sci-tech, not pseudoscience. Do not post off-topic.

•♥ Integris

  • Supported file types are: GIF, JPG, PNG, WEBM
  • Maximum file size allowed is 5120 KB.
  • Images greater than 200x200 pixels will be thumbnailed.
  • Currently 742 unique user posts. View catalog

  • Blotter updated: 2018-08-24 Show/Hide Show All

We are in the process of fixing long-standing bugs with the thread reader. This will probably cause more bugs for a short period of time. Buckle up.

Movies & TV 24/7 via Channel7: Web Player, .m3u file. Music via Radio7: Web Player, .m3u file.

WebM is now available sitewide! Please check this thread for more info.

replacing speaker with 1/4" jack chrissychris 16/12/19(Mon)21:09 No. 16401 ID: 8ed2cc

File 148217815616.jpg - (110.29KB , 1000x1000 , 7chan post photo.jpg )

Alrighty, I am looking for some help.

For the sake of experimentation and fun, I'd like to replace the speaker of a shitty kids toy (very similar to the one in the pic) with a 1/4" audio jack so it can play through a larger amp, possibly even through guitar effect pedals.

I've already tried this twice. Taken apart the toy, soldered in a 1/4" jack, and plugged it in. Both times I ended up with a reallyyyy spotty and quiet sound. At first I thought it may be a bad soldering job, but now I feel like it could be due to the low power of the toy, it takes 3 AA batteries.

So what's the deal here? Any ideas what could be wrong?

Anonymous 17/01/01(Sun)23:02 No. 16405 ID: 67f38c

It has nothing to do with the electrical power. Real electric guitars don't have any batteries. The issue could be that the amp is designed to work with the signals from a guitar's pickup, which are probably not the same as the signals from a speaker. If I had to guess, the pickup would be taking the signals from each string individually, while the speaker from this kid's toy is taking the entire sound as a whole.

It's also possible that the teeny-tiny magnet in that speaker just isn't strong enough to send a strong signal. I'm not sure what you could do about this.

Anonymous 19/05/08(Wed)19:01 No. 16767 ID: c6dd74

the toy generates a signal of a much lower power (higher impedance) than a guitar pickup is expected to, that's why it's very quiet. as for it being "spotty", the most likely reason is that the sound you hear from the toy is largely due to the way the tiny speaker reacts to the incoming "lo-fi" signal. if you take the speaker out of the chain, you'll most likely lose the sound you're presumably trying to capture.

tl;dr - you can find a way to preamplify the signal before it gets to the amp, but it will still be "spotty". better yet, install a mic/pickup next to the toy's speaker.

the poster above is misinformed. passive guitar pickups don't draw current from batteries, they generate it when metal strings vibrate over the magnetic pole pieces of the pickup. it's safe to assume the toy does not have pickups and therefore needs to generate the signal itself by drawing current from the batteries. the toy is only expected to output its sound into a tiny, low-power speaker, so an appropriately low-powered signal is generated, which is too quiet for a guitar amp because of a much higher impedance, and sounds "spotty" because the signal is too "lo-fi" to sound good on a larger speaker.

as for what was said about guitars:
>Real electric guitars don't have any batteries
a lot of electric guitars/basses use 9V batteries, but plenty don't. an active pickup still generates current, but that signal is too low-power to go straight to the amp and needs to first go through the built-in active preamp. active pickups generate a low-power signal which is supposedly easier for the active EQ to handle and makes the signal less noisy (debatable). active pickups can be designed with a particular tonality in mind even if it sacrifices the output - it works because the signal still goes through the preamp on the way out. on a fully passive instrument the pickup itself is responsible for generating enough current to produce a signal of an acceptable level, which often results in a "nice tone vs high output" tradeoff situation. often times the pickup itself is passive, but the battery is needed for the EQ. active EQ can give you independent control of low/mid/high frequencies, whereas passive EQ is generally limited to a treble roll-off. some guy made optical pickups, which uses light emiters and photodetectors. those obviously require batteries.

>the pickup would be taking the signals from each string individually
not strictly wrong, but not exactly true. in most pickups there are separate magnet pole pieces that pick up the vibrations of each string individually, but the signal that the pickup outputs is generally one and the same. there are exceptions, i think it was Roland who made a pickup that output the sound of each string separately.

Anonymous 19/06/25(Tue)16:46 No. 16794 ID: 108b48

Try hammering the speakers a bit
Usually the sound is just hidden inside and you need a little force to yank it out

[Return] [Entire Thread] [Last 50 posts]

Delete post []
Report post