# Footnote Electric Guitar Amp - $11.99



## Guitar101 (Jan 19, 2011)

At Princess Auto. They must have bought out all the old stock. This is just the amp and not the SKB pedal board.


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## jb welder (Sep 14, 2010)

Good deal. No speaker or power supply, but does have a built in cable tester! Looks like there are 2 amp chips on board also.
Footnote Electric Guitar Amp/Pedal Board Module | Princess Auto


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## Guitar101 (Jan 19, 2011)

Waiting for a comment from mhammer. He's our goto pedal guy.


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## LaRSin (Nov 27, 2006)

Thought it was coming the USA , But know Oh well My mistake


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## greco (Jul 15, 2007)

Guitar101 said:


> Waiting for a comment from mhammer. He's our goto pedal guy.


IIRC, @mhammer started a thread about these quite some time ago. They were ~$20.00 at that time.



LaRSin said:


> It will be $40. by the time you get it .


What do you mean by this?


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## LaRSin (Nov 27, 2006)

greco said:


> IIRC, @mhammer started a thread about these quite some time ago. They were ~$20.00 at that time.
> 
> 
> 
> What do you mean by this?


Thought it was coming the USA , But know Oh well My mistake


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## mhammer (Nov 30, 2007)

I bought one some time back. Decent value for the money (and Princess Auto had them for $20 at that time). The EQ section works fine and the additional built-in features are useful. Not visible from the pics or website info is that it can be run on batteries and has a molex connector for attaching a battery supply. 

The power amplifier section is actually capable of more output with a higher voltage power supply (e.g., 12-15VDC). A "bridging amplifier" using those two power-amp chips is capable of 14W or more, easily, with higher supply voltage. The limiting factor is that the unit relies on the regulated 9VDC fed to the board to supply the 9V pedal power jacks directly, with no additional regulation or filtering. That, in itself is not a problem or issue. It just means that if one goosed the power a bit with a different supply, you'd have to provide additional down-regulation, between the main board and sub-board with the pedal-power jacks to still feed them with +9VDC, despite feeding the rest of the amp with more. If there is demand, I can post a little tutorial on how to do it. Alternatively, if you're happy with 5W, nothing wrong with that. And if you have a pedalboard power supply you're happy with, you can even opt to use those 8 holes in the front panel for built-in effects, instead of pedal-power jacks. 

There is a Line Out, though I'm having some difficulty figuring out how and where it taps things from, based on the circuit drawing. It is preceded by a 10uf electrolytic cap labelled E11 on the board. If you can find E11 on the diagram below, you're a better man than I. So I can't tell, just yet, what sort of signal it is able to feed.

The other thing I'll mention is that the design does not provide much gain. So if you're looking to use it as a cheap practice amp with some overdrive, you'll either have to use a pedal for that grind, or else modify the unit for higher gain and maybe some clipping. As the circuit diagram below shows, op-amp U1-2, at the input of the "guitar in", is used as a "unity-gain buffer" (i.e., provides no amplification). The stage after it (U1-1) has a maximum gain of x2.27, which is not very much at all. Replacing the Volume pot with a higher-value unit, like maybe 50k or even 100k would make the unit more responsive and able to provide greater loudness.

All in all, though, for $12+tax, a worthy platform for modding or simply making a bench amp.


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## mhammer (Nov 30, 2007)

So I thought, "What the hell. May as well make it a nice little portable practice amp." I unscrewed the row of minijacks and removed the lower board.








With the daughter board out, there is plenty of room below the main board to make use of the holes, and maybe install some other things.








And because, as I noted yesterday, the front end of this thing doesn't seem to have much gain, I made a simple mod to the input stage, and gave it a gain of 11x, by cutting one trace and tacking three additional parts on the copper side. Gain is multiplicative, so in tandem with the stock gain stage, the preamp now has a maximum gain of just under 30x. Next, I dug up a 12V power supply, and, plugging in to the dual 6.5" minicab I posted about last autumn, fired it up. Holy crap, this thing is loud! I wish my Princeton were that loud. The power supply was but a meager 500ma, so I'll need to dig through the tub of adapters for something a little more stout to handle those power chords. But so far, this little puppy shows promise for a delete-bin amp. Next up is a cab to make it a proper "head". And I have to figure out what I want to do with the row of 8 holes. Perhaps delay and tremolo, though I have to figure out where the insert points would be. More to come as I progress along.


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## sambonee (Dec 20, 2007)

Sweet. I want one. Thanks Mark. You’re always very informative


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## mhammer (Nov 30, 2007)

My pleasure. The cab is made and I'm tolexing it at the moment.


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## Guitar101 (Jan 19, 2011)

"_And I have to figure out what I want to do with the row of 8 holes._"

Hey Mark. You can put some dowels in the holes and hang stuff on them.


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## mhammer (Nov 30, 2007)

Tolexing is done. Here's the basic cab, using two pieces of pine from the $1.50 a piece pile at Home Depot.








The cab completely covered with the amp inserted, though I have to figure out how I want to mount it and connect a power supply. I have a couple of 6V/4.5Ah lead-acid rechargeable batteries that I'm debating whether to rely on.








The amp/cab seated atop the ported mini-cab I made last year with the two 6.5" Eminence speakers.








Now I just have to figure out what I want to add in the way of effects. Found an etched and drilled board for the Madbean "Cavedweller" project, which is a basic PT2399 3-knob delay, and another etched-and-drilled board for a Tonepad Big Muff Pi project. I think I can also perf up an envelope-follower circuit to feed an LED/photocell combo and use the modified first stage of the amplifier as a compressor.

I love taking sow's ears and turning them into silk purses. Now all I have to do is take my resurrected Guyatone guitar and SKB "stack" to a gig.


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## mhammer (Nov 30, 2007)

Apparently, Princess Auto is also carrying the 6.5" Eminence speakers intended to go with the amp, for just under [email protected] If you look at promo videos for the amp itself, it was supposed to be installed in an oversized pedalboard, like this, with that speaker. But sticking them in a cab is better.


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## mhammer (Nov 30, 2007)

My attention was originally drawn to those speakers and amp on the Parts Express website. The page advertising the amp+speaker+PS combo has a gallery of builds by customers. There are some pretty impressive and creative little amps, including MUCH better tolex work on their part. "Build Your Own FootNote Guitar Combo Amp - Components Only" from www.parts-express.com!


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## Verne (Dec 29, 2018)

Some of those builds are awesome !!! Some rather comical in their ideas. If I had any sort of electronics or wood working knowledge, I'd be all over one of these and build something for an "anywhere" session. At work during break for instance.


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## LaRSin (Nov 27, 2006)

Are saying @mhammer all you have to do is plug a 12 volt power supply say from a laptop with wright polarity and it well give you 14 watts , sorry not really technical at these things ,with no other mods,, I have one of these laying in parts drawer..


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## mhammer (Nov 30, 2007)

LaRSin said:


> Are saying @mhammer all you have to do is plug a 12 volt power supply say from a laptop with wright polarity and it well give you 14 watts , sorry not really technical at these things ,with no other mods,, I have one of these laying in parts drawer..


Yes, although opinions vary as to whether computer power supplies are optimal for audio purposes. Do note, however, that the difference in loudness between 5W and 12-15W is not all that much. The bigger increase in loudness comes from modifying the input stage for more gain. In my own instance, I bumped it from unity gain to 11x.


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## mhammer (Nov 30, 2007)

Just back from the recently opened Princess Auto out by the Canadian Tire Centre. They had stock on the amps, so I picked one up, but unfortunately they were out of stock on the speakers. They might have some in the other store, but it's the complete other end of the city. It was a 13km drive to one of them, and would be another 28km to go to the other one. I think I'll wait until I have a reason to be in that end of the city.

Mark


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## oldjoat (Apr 4, 2019)

can you post the new values for components to U1-2 and which track to cut ?


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## mhammer (Nov 30, 2007)

Sure. Cut the trace between pins 6 and 7 on the chip labelled U1. You'll probably want to use a magnifier to make sure there isn't any remaining copper between them. I put a 20k resistor between pin 6 and 7, but feel free to use other similar values (e.g., 15k, 18k, 22k). I ran a 2k2 resistor in series with a 2.2uf electrolytic cap from pin 6 to the nearest reference-voltage point. There are many choices there, but I went with the point that necessitated the least awkward sort of positioning of components. The 2.2uf cap yields a bass rolloff starting around 36hz, so going with pretty much anything from 1uf to 4.7uf is just fine.


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## oldjoat (Apr 4, 2019)

Thank you ....


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## LaRSin (Nov 27, 2006)

I ordered the speakers online from Princes Auto and this is how they came , They said going send me another set ,,


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## greco (Jul 15, 2007)

LaRSin said:


> I ordered the speakers online from Princes Auto and this is how they came , They said going send me another set ,,
> View attachment 249874


 Nasty!


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## torndownunit (May 14, 2006)

LaRSin said:


> I ordered the speakers online from Princes Auto and this is how they came , They said going send me another set ,,
> View attachment 249874


What's the problem?


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## mhammer (Nov 30, 2007)

LaRSin said:


> I ordered the speakers online from Princes Auto and this is how they came , They said going send me another set ,,
> View attachment 249874


I would hope so! That's pretty pathetic. At least you can measure and cut a baffle while you're waiting.


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## jb welder (Sep 14, 2010)

Wow. Hello Kijiji with the "rare Link Wray speakers for sale".


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## mhammer (Nov 30, 2007)

Good call, although I think one is the Dave Davies model.


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## LaRSin (Nov 27, 2006)

I got the replacement speakers yesterday from princess auto ,, There not very good , So anyone wants them for what I paid for them , Lets say $11.00 a peace.


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