Technical question about a homemade stomp box.

Hi all,

I made a stomp box so i can tap my foot on it and have a beat alongside my guitar whilst i play. However it does not work well at all.

A while back i saw some friends play a gig at a venue, their stomp box sounded lovely, a nice deep thud to it, so i asked what kind it was. When i looked though, it was homemade. Literally all it consisted of was a small section of chipboard wood, a layer of carpet stuck on top, a car speaker screwed upside down onto the carpet and into the wood....then a guitar lead was stripped one end, that end was wired onto the speaker and the other end plugged into the venues amp. Like i say, it sounded gorgeous....

So i recreated it at home. A friend gave me a 450w car speaker which i used as per above, but all i have to plug it all into is a 30w Roland Street Cube amp.

All i get is a kind of tapping sound, no deep bass-like thud at all.

So what i'm wondering is....is it because i have a crappy little 30w amp that i'm not getting a nice beat from it?......or is it something to do with the mismatch between the 450w car speaker and the 30w amp? Should i try a smaller car speaker on the board?

A local guitar shop said its probably just my EQ settings on the Street Cube that needs adjusting, but after much fiddling, it still sounds bad.
Any suggestions would be most welcome....i know nothing about the technical side of sound and it's equipment.

Or has anyone built their own successfully?

I'd rather not have to pay out a fortune for a huge amp to plug into.

Thanks in advance.

CX.

I have built effects in the past but I'm not quite getting what you're describing.

Ok, I looked it up. It depends on what you're using for a trigger, how did you make yours?

a reply to: HalWesten

Ok you've lost me already lol Whats a trigger? I made it exactly as described above....wait, i'll try and take a picture......brb...

CX.

a reply to: CX

en.wikipedia.org...

There are commercially produced stomp boxes available, but performers often[how often?] simply mount a dynamic microphone inside whatever wooden box they have handy. Some homemade stomp boxes include customized features such as a built-in preamp or equalizer.

In 2010s-era use, a simple piezo transducer (or sometimes a microphone) is located inside the box to allow amplification of the stompbox's bass sound through the PA system or bass amplifier.

Link below, appears you need a few more watts on the amp to drive a 450 w speaker. Make also sure the impedance is matched



rftech.custhelp.com...

Press on the cone of the speaker. If you feel any grinding, the voice coil is blown. It should move in and out smoothly with no grindy grindy. Dont push on the dust cap (center cap) you may make it implode.

It also may require a little more umph to move it.

If it's a poly cone, it may need a little more power to move it. A paper cone should be able to move with a lower powered amp running it no problem.

I have a Roland AC amp as well. No bottom end at all, but! On the back there should be a low out. I bought a cheap store brand powered 15” PA speaker and it sounds incredible. My guess would be no lows for the thud. It was around $180 for the 15. Also try the polarity on the car speaker.

originally posted by: drz400
Press on the cone of the speaker. If you feel any grinding, the voice coil is blown. It should move in and out smoothly with no grindy grindy. Dont push on the dust cap (center cap) you may make it implode.

It also may require a little more umph to move it.

If it's a poly cone, it may need a little more power to move it. A paper cone should be able to move with a lower powered amp running it no problem.

The cone material shouldn't make a difference but the flexible ring around it does. Remember the 70s home speakers that used a foam ring instead of just the paper cone going all the way to the rim? They allowed more movement to move more air so the bass would come out better. Or that was the theory anyway. They also required less power to move the cone because they were more flexible than the paper. I have a Peavey 4x10 pro cabinet for my bass that moves more air and has a more solid low end than my 15" EV SRO does. Both cabs are ported properly, the 15" cab is actually an EV design (free from their website) so you can build your own and not have to guess at the details.

When we used to busk on the street, we used a rig like this. That samsonite has a sweet tone!!

a reply to: CX

I thought you were talking about Stompin Tom Connors method for a second.

Interesting.

a reply to: CX
Sounds like the speaker may be to heavy duty to work well as a transducer. I think you would get better results with a mic or a piezo but if you’re dead set on using a speaker, I would try a couple different ones before giving up.

originally posted by: olaru12
When we used to busk on the street, we used a rig like this. That samsonite has a sweet tone!!

I've always like the nice tone the drum kick makes rather than the human foot which can depend on the shoe that one is thumping with the sole rubber, leather, or a wooden dutch boy shoe. My guess is the impedance difference between the guitar pickup output and the high wattage of the speaker output.

The best sounding performance I ever saw with a sound board was JJ Cale by himself playing his heavily modified acoustic electric Stella guitar and a sound board he thumped his foot on. With Mr. Cale's knowledge of sound tone and such I would imagine he wired the board himself.

It was a magical night early 70's.

a reply to: CX

The 450W rating on the speaker is the maximum input wattage, and should have no bearing on the sound of the speaker with less wattage (just less volume at max power). 30W should be more than enough to drive your speaker. Same thing for an impedance mismatch. If you were driving a 4 ohm speaker with an 8 ohm output the amp might get hot and be overdriven at max output, but otherwise should not be affected. Something else is going on.

What are you using for a pick up? You need some way to electronically capture the sound you are trying to amplify (like a mic for example). The mic would then be run into a pre-amp, and the output of the preamp would be an input to the main amp. This is how a standard drum kit is set up. (depending on the mic, you may also be able to input it directly to the amp)

Something like a guitar pick up would not really work in this case because these use sustained vibration frequency from a string which a drum doesn't have.

ETA - Re-reading your OP, looks like you've got all kinds of issues. If I'm reading correctly, you've taken a guitar lead, stripped it and wired it to the speaker and then plugged it into the amp. If this is the case, the wire gauge of the guitar lead is not sufficient to take the amperage coming out of the amp to the speaker. So no matter what, this will be a problem. A guitar lead usually uses a wire gauge which is only suitable for a line-level output. What's coming out of your amp is way more than line-level. And again, I don't see anywhere where you have described how you're getting the sound "into" the amp (i.e. pick up and input). Maybe I'm misunderstanding though.

a reply to: Flyingclaydisk
He’s using the speaker as a transducer/pickup/mic and running it into the input of the amp. The speaker itself does not put out sound, it picks up the sound.

Something like this www.instructables.com..." target="_blank" class="postlink">Stompbox

Would it be possible to gaff tape a piezo to the soul of a shoe and eq in the amp for a nice rhythm kick?

a reply to: olaru12

They are great! One of my fave banjo buskers, Morgan O'Kane uses similar...sound lovely.



Thanks for all the knowledge everyone, much appreciated. I'll have a play around and see what I can come up with.

CX.

a reply to: Flyingclaydisk

Nope you read it correctly.....I just know nothing about sound and obviously ballsd it up. 😁

No pick up then seems to be one of the main issues.

Cheers.

CX.

Can you contact the folks who had the one you loved?

Even if you try to copy the concept, it definitely doesnt mean you will get something you like. Best to start with an *exact* copy of the original design and go from there.

Even the tolerance differences of the components can make two examples of the same circuit sound different (for better or worse).

30w is more than enough for pretty much anything in this arena, but the amp itself may not be able to put out exactly what you are looking to achieve regardless of power rating.

Enclosure volume will matter too.

But, much of it is going to be subjective.. So.. Try to copy the original signal chain as precisely as possible. Still dont expect it to sound exactly the same, but should get you closer.

originally posted by: CX
a reply to: Flyingclaydisk

Nope you read it correctly.....I just know nothing about sound and obviously ballsd it up. 😁

No pick up then seems to be one of the main issues.

Cheers.

CX.

You don’t need a pickup, your speaker is your pickup. I think using a 450 watt speaker maybe to large or has to heavy of a magnet for what you’re trying to do.

I believe most people that have posted are confused on how this works. The speaker is used to pick up the sound not to put sound out. Here’s a few videos that explains how to make one. I thought the one made from guitar pickups was rather cool. I think I may make one of these myself.

.

Here’s one using guitar pickups

I've done that before (used a speaker as a mic) but it didn't dawn on me that that's what he was trying to do. Theoretically it would work, but in the long run if you're not into building things like this it can be a lot cheaper just to buy a pre-made unit. You can sink a lot of time into doing things like this over and over until you get it right. But if you like doing that, more power to ya!

a reply to: HalWesten

Something like this is SUPER easy to build with just some basic, googled knowledge.

However..

Getting it to sound like desired? Oh, thats a whole thing unto itself. Due to the highly subjective nature, it also means that expert/master levels of knowledge can even get in the way!

Not to mention, sometimes things just come together bafflingly great. I just finished setting up a single cut to sell, and it came out incredible. Literally one of the best sounding and playing guitars I have come across. That has a price point of $600. Using pretty standard, off the shelf parts that are in thousands of other guitars.

Everything Ive worked on always comes out great, even so far as people saying I just put "something like magic" into the instruments. But sometimes.. It comes together like real magic, with little rhyme or reason beyond "oh my.. this is good."

Maybe a bit esoteric, but when it comes to this stuff.. If you come across something you genuinely fall in love with.. Try to buy it right then and there.