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#1
Hi Everyone!

I'm a guitarist as well as a design student. Being a musician, I thought it would be a fun project to design a portable amplifier for street musicians. I am from the U.S., but I'm studying abroad in London for the semester, so my primary focus is buskers (street musicians) in London, but it could really be used anywhere. I have been interviewing several buskers around the city, but I thought I would also see if anyone here would like to help me out/give me some feedback on my project. Anyone who has had any experience busking/street performing, I'd love to get your input! Or even if you haven't done much street performing, I'd still love to hear what you guys have to say! I've included a few images with some sketches/renderings of a few different concepts I have been working on, and I'd love any feedback on them, even if its harsh/critical, I promise my feelings won't be hurt!

Also, for those who do have experience busking/street performing, if you'd be interested in answering any or all of the questions below, I'd love to hear what you have to say.

1. What amp do you currently use?

2. How do you like it?/Is there anything that you'd wish to change about it if you could or things it doesn't do that you wish it did?

3. How far do you typically have to travel when you go busking? (Do you take the tube, bus, walk, or all three?)

4. How do you carry your amp and equipment?/Is it hard to transport?

5. Do you ever sit on top of your amp and use it as a chair?

6. If somebody were to design you your ideal amp, what are the most important things it would do (For example: portability, ability to play backing tracks, durability, stylishness, etc&hellip

Also, if you have anything else you'd like to add that I didn't ask about, I'd love to hear it! Thanks in advance for your help!



#2
imo, the difficult thing here it's not designing something particularly stylish or anything:
1. an amp like this has to run on batteries, so it's gotta be efficient.
2. an amp like this has to be easy to carry around, so it's gotta be fairly small
3. an amp like this has to be fairly small, so you gotta get/design a small guitar speakers that sounds good

I'm not sure about the first design for two reasons: the speaker would likely not sound at its best in that position, and the thing would end up being pretty deep - even using a pretty light and small and efficient jensen neo 10, the thing would need to be at least 20cm deep.

The second design is a plain bad idea, the person sitting on the amp would block the sound coming from the speakers with at least one of his legs.
What's the purpose of opening the back of the cabinet here anyway?
Just stuff the back with foam or make the cab bass-reflex and save on that part.

So yeah, I'd concentrate on the engineering more than on the design.
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#4
Quote by Spambot_2
imo, the difficult thing here it's not designing something particularly stylish or anything:
1. an amp like this has to run on batteries, so it's gotta be efficient.
2. an amp like this has to be easy to carry around, so it's gotta be fairly small
3. an amp like this has to be fairly small, so you gotta get/design a small guitar speakers that sounds good

I'm not sure about the first design for two reasons: the speaker would likely not sound at its best in that position, and the thing would end up being pretty deep - even using a pretty light and small and efficient jensen neo 10, the thing would need to be at least 20cm deep.

The second design is a plain bad idea, the person sitting on the amp would block the sound coming from the speakers with at least one of his legs.
What's the purpose of opening the back of the cabinet here anyway?
Just stuff the back with foam or make the cab bass-reflex and save on that part.

So yeah, I'd concentrate on the engineering more than on the design.


Thanks for the feedback, I really appreciate it! I, too had many of the same concerns. I wasn't sure if the speaker propped open like in the first concept would significantly detract from the sound quality or not. I asked a couple of employees at guitar shops, who seemed to think it would work, but they definitely could have been wrong, since it is something that hasn't really been done before. And also the depth is definitely another factor to consider. I'll look into the neo 10, but yes, it definitely is hard to find very thin speakers that still sound good.

And as far as the second concept, I completely agree with you. I have seen quite a few street performers, though, sitting on their amps with their legs blocking the speaker, but I had the same thought (that it would be blocking a lot of the sound from projecting). So maybe if there were some way that this could still be done, but with both legs clearing the speaker. I'll try to think of some more ideas!

Unfortunately I am not an engineering student, so there's not much I can do alone (as I'm not currently working with an engineer) as far as very technical innovations like creating smaller, more efficient electronics, but hopefully I can find some creative ways to tackle some of these problems. But maybe you're right, maybe this is a bit more of an engineering project than a design project as far as tackling the portability factor. If I decide to pursue the project much further, I will definitely need the help of an engineer in the future. Thanks again for your input!!
#6
Roland Micro-Cube is pretty damn good. Here in Cali we have severe noise restrictions so it needs to sound decent at street noise volumes. Get too loud and they ask you to leave. Super-portable, battery powered, decent range of quality DSP effects, possible mic input are all desired features.

Your exposed back speaker design will sound like schite with no bass response at all. A tuned open back cabinet will still generate decent bass.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#7
Quote by Cajundaddy
Roland Micro-Cube is pretty damn good. Here in Cali we have severe noise restrictions so it needs to sound decent at street noise volumes. Get too loud and they ask you to leave. Super-portable, battery powered, decent range of quality DSP effects, possible mic input are all desired features.

Your exposed back speaker design will sound like schite with no bass response at all. A tuned open back cabinet will still generate decent bass.

Awesome, thanks for the response! I've noticed a lot of people use the micro cube/it definitely seems to be a favorite. Would you mind elaborating on what you mean by having a "tuned open back cabinet?" Thanks!
#8
Busker amp should also have the ability to play other audio files so I don't think guitar speakers will work, more of a general PA speaker approach is required and some kind of mix concept between the two.

I like the folding concept (1st one) . Who knows, maybe even do it as a built-in guitar case?
#9
This is a better explanation of cabinet tuning than I can give. Cabinet tuning is important if you want good sound.
http://www.ultimate-guitar.com/columns/gear_maintenance/cabinets_for_guitars.html
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#11
Quote by diabolical
Busker amp should also have the ability to play other audio files so I don't think guitar speakers will work, more of a general PA speaker approach is required and some kind of mix concept between the two.

I like the folding concept (1st one) . Who knows, maybe even do it as a built-in guitar case?

Great, thanks for the feedback and ideas!
#12
I like the first design.

A thought- what if you built the speaker into a guitar case? It would give you a little more working room, and would be one less thing for the busker to carry.
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#13
Quote by dannyalcatraz
I like the first design.

A thought- what if you built the speaker into a guitar case? It would give you a little more working room, and would be one less thing for the busker to carry.

Thanks Danny! Yes, I really do like that idea that you and Diabolical proposed of building an amp into the guitar case. It's a really cool concept and definitely worth exploring! Thanks for the input I appreciate it!
#14
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#15
Quote by Cajundaddy

Hahah yes, I came across this today as well. Doesn't look like too much has been done since that one. It might be cool to try to create a new, better version of this. Thanks!
#16
I didn't know about that, but I definitely agree that it could be improved upon.

For instance, putting the speaker(s) in the lid instead of the back could change the overall utility of the whole thing.
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
#17
I'd buy the first one if it worked, regardless of sound.
The second one seems to be a combo with a pillow on top. That may work if you have a wagon and a power generator.
I'm pretty sure guitar center sells the third one.
I'd prefer a "fanny pack" amp head with a 4x5" vest myself. Maybe a tubescreamer built into one shoe, delay built into the other with Reebok Pump style footswitches. I'd quit my job and live off coolness if you made that.
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#18
Quote by lucky1978
I'd buy the first one if it worked, regardless of sound.
The second one seems to be a combo with a pillow on top. That may work if you have a wagon and a power generator.
I'm pretty sure guitar center sells the third one.
I'd prefer a "fanny pack" amp head with a 4x5" vest myself. Maybe a tubescreamer built into one shoe, delay built into the other with Reebok Pump style footswitches. I'd quit my job and live off coolness if you made that.

Hahahaa! If and when I make that, I'll be sure that you're the first to get one . And thanks for the feedback on my concepts, I appreciate it!
#19
A padded seat built into the top of a busking amp is a great idea. I have considered that myself. Make sure the wheels are good too, they have to deal with all sorts of surfaces.
That's the winner, hands down. It would be big enough to be able to put out a decent sound. But a seat, man. Busker needs a seat.
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#20
^ maybe a connector to attach your walking stick too?



seriously, though, a seat sounds like a good idea
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#21
I've used two kinds of battery-powered amp (and you see a LOT of buskers on the Third Street Promenade in Santa Monica).

One is the Pignose HOG 20 (they make a 30 as well). It's a 20-watt rechargeable battery powered basic amp with a 6.5" speaker. Not bad, not great.

But the killer app for this is the Carvin StageMate 400D with replaceable lead-acid batteries. http://www.carvinguitars.com/products/S400D

100W RMS power, FX, built-in mixer, 10" woofer, 1" tweeter, closed-back speaker cabinet (better bass), speaker stand mount, extension speaker available, 3 hours of power on one battery (interchangeable batteries or works off AC), 4 channels 20-20,000Hz, less than 1% THD, about $499. Handles instruments, vocal mikes, tape/CD/MP3 players.
#22
Make an amp that can make coffee..

You will become a millionaire..

Let the amp warm up the water, and you will get close to boiling point with a bit of extra battery power.. The residual steam can then be used to drive gears to generate power again.

Anyways, I'm also for the seat.. Never seen it, and "just an amp" would never compete against a cube.

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Last edited by xxdarrenxx at Apr 27, 2014,
#23
Quote by xxdarrenxx

Let the amp warm up the water, and you will get close to boiling point with a bit of extra battery power.. The residual steam can then be used to drive gears to generate power again.


Didn't Bugera already do that?
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

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Et tu, br00tz?
#24
Quote by Cathbard
A padded seat built into the top of a busking amp is a great idea. I have considered that myself. Make sure the wheels are good too, they have to deal with all sorts of surfaces.
That's the winner, hands down. It would be big enough to be able to put out a decent sound. But a seat, man. Busker needs a seat.

Awesome, thanks for the feedback! Cool to hear that someone else likes the seat idea. It would definitely need more work, but I think it's got potential. And I agree about the wheels. I'm even a bit hesitant to put wheels on it at all because I'm afraid all the banging around might put a lot of wear on it. But if I did add wheels, maybe they could be rugged/have some give to try to absorb some of the impact. Thanks!
#25
Quote by Dave_Mc
^ maybe a connector to attach your walking stick too?



seriously, though, a seat sounds like a good idea

Hahah thanks!
#26
One solution is to build it with an integral retractable dolly type construction. The handle telescopes vertically out of the back, letting you pull it like luggage. Maybe even strap your guitar case to it.

Then, when you set up, push the handle down and you're ready to go.

Bonus points- use the rolling wheels to recharge the amp's battery.
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
#27
Quote by dspellman
I've used two kinds of battery-powered amp (and you see a LOT of buskers on the Third Street Promenade in Santa Monica).

One is the Pignose HOG 20 (they make a 30 as well). It's a 20-watt rechargeable battery powered basic amp with a 6.5" speaker. Not bad, not great.

But the killer app for this is the Carvin StageMate 400D with replaceable lead-acid batteries. http://www.carvinguitars.com/products/S400D

100W RMS power, FX, built-in mixer, 10" woofer, 1" tweeter, closed-back speaker cabinet (better bass), speaker stand mount, extension speaker available, 3 hours of power on one battery (interchangeable batteries or works off AC), 4 channels 20-20,000Hz, less than 1% THD, about $499. Handles instruments, vocal mikes, tape/CD/MP3 players.

Awesome, haven't seen the Carvin yet. Thanks for sharing!! And yeah I've done a bit of research into the portable pignose amps and I really like them. I have yet to see someone using one out in London yet, however. Not sure if they sell them here.
#28
Quote by xxdarrenxx
Make an amp that can make coffee..

You will become a millionaire..

Let the amp warm up the water, and you will get close to boiling point with a bit of extra battery power.. The residual steam can then be used to drive gears to generate power again.

Anyways, I'm also for the seat.. Never seen it, and "just an amp" would never compete against a cube.

Hahahhh! Thanks for the feedback on the seat as well.
#29
Quote by dannyalcatraz
One solution is to build it with an integral retractable dolly type construction. The handle telescopes vertically out of the back, letting you pull it like luggage. Maybe even strap your guitar case to it.

Then, when you set up, push the handle down and you're ready to go.

Bonus points- use the rolling wheels to recharge the amp's battery.

Yes, that is what I was starting to get at with the seat idea, with the sketch of the handle coming up. I like the idea of strapping the guitar case and also considered that. And using the kintetic energy from the wheels to re-charge the batteries would be awesome . I like that idea a lot!
#30
All you'd need in the wheel department is decent sized wheels with pneumatic tyres. The same sort of thing you look for in a trolley/dolly/handcart.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
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#31
Wouldn't you want hard rubber instead, so you never have to worry about a puncture?
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
#32
Quote by dannyalcatraz
Wouldn't you want hard rubber instead, so you never have to worry about a puncture?


I would. Every pneumatic wheeled cart I ever owned was flat when I needed it most. Long live solid rubber wheels.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#33
I'd rather have the shock absorption. Use wheels that are readily available so repairing punctures is easy to do. I've used many trolleys over the years and the only ones worth pissing on have pneumatic tyres. Is it that hard to keep tyres inflated? Seriously guys, wtf? You want pneumatic tyres for the same reason you want them on a pushbike. You don't want to get shit shaken up, on an amp that is far more important than laziness. You want to repair a tyre or the amp?
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#34
Good point.

OTOH, is that as big concern if the amp is solid state?
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
Last edited by dannyalcatraz at Apr 27, 2014,
#35
Good points. Yes I think if the wheels were easily replaceable/interchangeable pneumatic tires could definitely be a viable option. I, too have noticed that the rubber wheels, although more durable, are often not nearly as good at absorbing shock. And true, it would be more crucial if the amp were tube, but I feel like even a solid state's gonna have a lot of electronics you'd rather not get too shaken up.
#36
It's always a concern. Not so much but it's still something I'd consider a pretty major design issue. It speaks to longevity and warranty work. If your design results in failure, the design is faulty. And for the sake of tyres? It's a no-brainer. Any decent wheels/tyres should outlast the warranty period - but the amp? You start knocking the amp around and you could end up with a ****ing lot of returns.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
Last edited by Cathbard at Apr 27, 2014,
#37
If I do decide to further develop the second concept, I also still want to try to address the issue of the guitarist's legs blocking a lot of the sound. Not sure how much sound is actually blocked, and I'll definitely do some testing to find out.
#38
Won't matter. I've sat on an amp plenty of times. You'd have to have pretty fat legs for them to block the sound appreciably. Like, needing to be hoisted out of bed with a crane, fat. I don't think that's going to be your target audience for an amp designed to be sat on and carted around on the bus, do you?
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#39
Quote by Cathbard
Won't matter. I've sat on an amp plenty of times. You'd have to have pretty fat legs for them to block the sound appreciably. Like, needing to be hoisted out of bed with a crane, fat. I don't think that's going to be your target audience for an amp designed to be sat on and carted around on the bus, do you?

Hahahhhah. Very good point
#40
if you were going to use one as a seat, you must consider weight. i am 6'1" 260lbs i am just kind of big and more muscular than fat, i realize i am probably on the larger than average, but it still should be considered.

also a concern is it would get heavier the more you reinforce it, making it less practical to be moving. its adding weight.

personally i don't think the seat concept has the least practical.

also with speakers you have to find a shallow enough speaker to make the pack not too thick.

also a nice padded strap for your back would be a plus in general, more comfortable.
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