Replies to This Discussion

Permalink Reply by Brunsi on April 1, 2010 at 8:05am

Hello I am about to build a amp with this kit and have a question about adding the led. to those of you who added a led off of the led pod on the circuit board did you add a inline resistor or just run wires straight from the board to the led and back? Thanks
wesley carl said:

better


wesley carl said:

you can rip off the gain and wire it external im not afraid i just pulled it off with a pliers and soldered 3 new wires on the board to a switch


Mark Lillo said:

Hi ya Michael. I have used the Artec amp. It is a 2 watt amp kit that comes with a volume pot mounted right on the circut board and a 9v battery plug for 15.95 from Guitar Fuel. It also has a gain control on the board also, but you need to use a screw driver to adjust it. It works really well.

• ▶ Reply

Permalink Reply by Mark on April 1, 2010 at 11:24pm

I would seriously advise against attempting anything like that CB tube amp unless you have a lot of electronics experience. That design involves mains voltages and so has the potential for serious accidents if you get it wrong. One of the beauties of the simple solid state amps like the Smokey/Little Gem/Cricket/Minty is that they're easy and safe.
Bluesdog said:

If you'r looking for plans there is a full plan and schematic for a simple Cigar box tube amp in the free resources page, (
https://api.ning.com/files/Fyz9lPoEiAvBfgQz4aSyh-qetlTical0T9qPtE4M... ) don't know exactly how much power it will give you but it's (supposed to be) made from parts off a kid's/mobile record player... so i guess it will be in the 1-3w area. It's not battery powerd but they are pretty old plan's so that's no big surprise.

Shouldn't be to hard to find one off those record players for under 10-15 buck's or less, especialy if you look for broken ones people sometimes put up for parts. All you need is the amplifier stuff so broken moters, arm's, mc element's (allthough you can use mc elements as pick-up's for one string diddly bow's) don't matter.

Sure it is more work than a smokey or minty and less mobile but it will be a real DIY tube amp made from vintige stuff!

• ▶ Reply

Permalink Reply by Mark on April 2, 2010 at 12:46am

The Smokey, Little Gem, and Minty as well as the "1w" Maplin amp (available in the UK), are basically variants of the same thing - they're all essentially an LM386 chip. The differences come down to a few resistors and capacitors, which adjust the tone and/or gain a bit. The Ruby (designed by runoffgroove.com) and Noisy Cricket (from Beavis Audio) are not a lot more complicated - they basically add a JFET input buffer to the front of an LM386 circuit.

I've started out by buying Maplin kits because they come with a ready made PCB so I don't need to mess around with perf board - they cost £5 (about $7.50). On top of the kit I then need a handful of other parts which I generally have lying around.

If you're new to building your own electronics then I'd suggest getting a kit (eg. Maplin or Minty) and building that first. Then (using the Beavis and runoffgroove circuit diagrams as a guide) try changing or adding or omitting parts to see what diffrence they make. There's a circuit diagram amongst my photos which shows what I ended up with when I did this using a Maplin board.

One recommendation I'd definitely make is that, if you don't have a volume control on your guitar, then you should incorporate some sort of input level control into your amp. In mine this just consists of a 10k pot.

Also, sound quality will depend a lot on the speaker you use. Tiny speakers will be quiet and are likely to lose a lot of bass. Bigger speakers will generally give you more volume and better tone.

Don't be fooled by too much talk of power as that isn't the same thing as how loud an amp sounds. Half a watt might not sound like much but consider that against a figure I saw quoted for the sound power level for a trumpet as being 0.3W. Now I'm not saying your amp will be anything like as loud as a trumpet, but it's an illustration that power isn't everything. An amp's power definitely has a relationship to the maximum amount of sound you can get out of it, but the thing that determines how much sound you actually get is how efficiently you convert the electrical power into sound - and that comes down to the speaker and the acoustic properties of the box it's mounted in. Also sound levels (as expressed in dB) have a logarithmic relationship to power, which means that doubling the power of an amp doesn't come anywhere near doubling its sound volume - and conversely halving the power of an amp will not reduce sound volume by anywhere near a half. Which is why people are sometimes surprised when they plug little LM386 amps into 2x12 cabinets.



MichaelS said:

Thanks Mark, mainly looking for a kit or plan to build into a cigar box. Thanks

Mark Werner said:

If you want a good little pre-built amp, the Danelectro Honeytone is hard to beat. Looks cool too, for only 20 bucks.

• ▶ Reply

Permalink Reply by MichaelS Country Boy Guitars on April 2, 2010 at 3:42am

Thanks for all the advise, I was planning on skipping the tube amp for one reason, I don't think I could find a kids record player with tubes at any tag sales near me, they all went away 3o years ago. I do like the simplicity of the LM386 based amps, how do they differ from the amp at Guitar Fuel? or is it also LM386 based, I can't tell.
Mark aka. Junk Box Instruments said:

I would seriously advise against attempting anything like that CB tube amp unless you have a lot of electronics experience. That design involves mains voltages and so has the potential for serious accidents if you get it wrong.


One of the beauties of the simple solid state amps like the Smokey/Little Gem/Cricket/Minty is that they're easy and safe.

Bluesdog said:

If you'r looking for plans there is a full plan and schematic for a simple Cigar box tube amp in the free resources page, (
https://api.ning.com/files/Fyz9lPoEiAvBfgQz4aSyh-qetlTical0T9qPtE4M... ) don't know exactly how much power it will give you but it's (supposed to be) made from parts off a kid's/mobile record player... so i guess it will be in the 1-3w area. It's not battery powerd but they are pretty old plan's so that's no big surprise.

Shouldn't be to hard to find one off those record players for under 10-15 buck's or less, especialy if you look for broken ones people sometimes put up for parts. All you need is the amplifier stuff so broken moters, arm's, mc element's (allthough you can use mc elements as pick-up's for one string diddly bow's) don't matter.

Sure it is more work than a smokey or minty and less mobile but it will be a real DIY tube amp made from vintige stuff!

• ▶ Reply

Permalink Reply by Dave Onastik on April 7, 2010 at 1:07pm

I have a question which should probably be a new post, but it seems all the right people are on this thread.
I want to install a noisy cricket inside my latest CBG. I plan to install one or two miniature 8 ohm speakers, along with the noisy cricket board. I already have a magnetic pickup installed, which would replace the J1 input jack, and the two speakers in parallel would be in place of the output jack. I would have a guitar an amp all in one.

Here's the catch.... I would still like the option of plugging the guitar into an external amp via the J2 output jack. If I wired the output jack in parallel with the two speakers, is this a do-able option?

If so, is it possible to turn the cricket off, and still send output to the external amp while using the volume pot for gain and the tone pot for tone? I'm not familiar with the characteristics of the LM386, but I'm wondering if the power is cut off to pin 6, it renders the chip useless, and Tone and Volume have no effect.

I did this on a previous build using the SDA-P amp from guitarfuel.com that has been mentioned numerious times on this thread. With their circuit, I can do as described above; 1) play thru the speakers on the guitar, 2) plug in and play thru the guitar speakers and an external amp, and 3) turn off their amp, but still use the volume to control gain for the external amp. I can't tell from guitarfuel website if the SP+ speaker output and the JK+ Jack output are connected on the board, and the board on my guitar is not accessible at this time.

I prefer using the noisy circuit because it has tone control, grit, plus I like the idea of building it myself.
Thanks for any assistance you can offer.

• ▶ Reply

Permalink Reply by BT Cohosh on April 8, 2010 at 3:36am

Michael--

I've built a Little Gem--it was a breeze to put together, and I had *no* previous electronics experience. That said, I'm seriously coveting the Noisy Cricket (a variant of the Ruby) on the beavisaudio site--it adds to the Ruby's input buffer a simple tone control. If you can get one of the 4 series (I think that's what it is) LM386 chips, and can find an 18 volt power source, it will put out close to 1 watt.

Tip: don't skimp on the speakers. I used an el-cheapo computer speaker (maybe 2 1/2 inches) on my amp at first, and *hated* it. Later, on a whim, I built a cabinet with 2 six inch car-stereo speakers I found on clearance--*BIG* difference in sound.

• ▶ Reply

Permalink Reply by Mark on April 8, 2010 at 3:42am

I don't think your plan will work as you've described it (which, as I read it, is that you hope that cutting power to pin 6 of the Noisy Cricket will allow a non-amplified signal to continue through the circuit).

A better solution to your requirement would be to wire in a selector switch - a toggle switch like you'd use for pickup selection on a two-pickup guitar. Wiring the selector between the output of the Noisy Cricket and the speakers will allow you to achieve all three of the options you described (playing through internal speakers alone, sending a signal via the Noisy Cricket and a jack socket to an external amp or both). The one thing this won't let you do is send an un-boosted signal from your guitar's pickup to an external amp. If you want that you'll need to put a selector between the Noisy Cricket and the pickup of your guitar.

An alternative is to consider using sockets with break contacts. An example of what I mean can be seen here http://www.maplin.co.uk/Module.aspx?ModuleNo=1263 (but I guess you can find a supplier that's more local to you). One wired between the output of the Noisy Cricket and the speakers would mean that when you plug in an external lead you disconnect the speakers and send a boosted signal from the Noisy Cricket to the external amp. One wired between the Noisy Cricket and the pickup of your guitar would mean that when you plug in your guitar lead it takes the Noisy Cricket out of the circuit and sends the signal instead to the external amp.

I don't see why you'd want to play through internal speakers and an external amp at the same time. I would think the useful options are (i) Internal speakers only, (ii) unboosted signal to external amp, and (iii) boosted signal to external amp. However the great thing about CBG building is that it's all down to your choice and if that's quirky then fine and dandy!

Whatever you do, it's a good idea to also put a simple on/off switch in the "+" line from the battery (which is what pin 6 is connected to). This will allow you to turn the whole circuit off when not in use and thus save you a lot of money in batteries. Cutting off only pin 6 will not do so because that it leave the battery to leak power through the input buffer.



David Armstrong said:

Here's the catch.... I would still like the option of plugging the guitar into an external amp via the J2 output jack. If I wired the output jack in parallel with the two speakers, is this a do-able option?
If so, is it possible to turn the cricket off, and still send output to the external amp while using the volume pot for gain and the tone pot for tone? I'm not familiar with the characteristics of the LM386, but I'm wondering if the power is cut off to pin 6, it renders the chip useless, and Tone and Volume have no effect.

I did this on a previous build using the SDA-P amp from guitarfuel.com that has been mentioned numerious times on this thread. With their circuit, I can do as described above; 1) play thru the speakers on the guitar, 2) plug in and play thru the guitar speakers and an external amp, and 3) turn off their amp, but still use the volume to control gain for the external amp. I can't tell from guitarfuel website if the SP+ speaker output and the JK+ Jack output are connected on the board, and the board on my guitar is not accessible at this time.

I prefer using the noisy circuit because it has tone control, grit, plus I like the idea of building it myself.
Thanks for any assistance you can offer.

• ▶ Reply

Permalink Reply by Dave Onastik on April 8, 2010 at 4:18am

Thanks Mark. That's a bigh help.

I actually just ordered a Minty Amp kit, and I'm going to take your suggestion for the output socket; Normally Closed contacts to the internal speakers, then bypassed to the external amp when a jack is plugged in. Looks like a simple solution.

You are right... there is no good reason to drive the internal speakers and the external amp at the same time.

I still want to try the noisy cricket, but the Minty Amp will give me a quick turnaround this time. As I said, I used the GuitarFuel SDA in a previous build. It works great, but sounds a little too "clean".

Mark aka. Junk Box Instruments said:

I don't think your plan will work as you've described it (which, as I read it, is that you hope that cutting power to pin 6 of the Noisy Cricket will allow a non-amplified signal to continue through the circuit).

A better solution to your requirement would be to wire in a selector switch - a toggle switch like you'd use for pickup selection on a two-pickup guitar. Wiring the selector between the output of the Noisy Cricket and the speakers will allow you to achieve all three of the options you described (playing through internal speakers alone, sending a signal via the Noisy Cricket and a jack socket to an external amp or both). The one thing this won't let you do is send an un-boosted signal from your guitar's pickup to an external amp. If you want that you'll need to put a selector between the Noisy Cricket and the pickup of your guitar.

An alternative is to consider using sockets with break contacts. An example of what I mean can be seen here http://www.maplin.co.uk/Module.aspx?ModuleNo=1263 (but I guess you can find a supplier that's more local to you). One wired between the output of the Noisy Cricket and the speakers would mean that when you plug in an external lead you disconnect the speakers and send a boosted signal from the Noisy Cricket to the external amp. One wired between the Noisy Cricket and the pickup of your guitar would mean that when you plug in your guitar lead it takes the Noisy Cricket out of the circuit and sends the signal instead to the external amp.

I don't see why you'd want to play through internal speakers and an external amp at the same time. I would think the useful options are (i) Internal speakers only, (ii) unboosted signal to external amp, and (iii) boosted signal to external amp. However the great thing about CBG building is that it's all down to your choice and if that's quirky then fine and dandy!

Whatever you do, it's a good idea to also put a simple on/off switch in the "+" line from the battery (which is what pin 6 is connected to). This will allow you to turn the whole circuit off when not in use and thus save you a lot of money in batteries. Cutting off only pin 6 will not do so because that it leave the battery to leak power through the input buffer.



David Armstrong said:

Here's the catch.... I would still like the option of plugging the guitar into an external amp via the J2 output jack. If I wired the output jack in parallel with the two speakers, is this a do-able option?
If so, is it possible to turn the cricket off, and still send output to the external amp while using the volume pot for gain and the tone pot for tone? I'm not familiar with the characteristics of the LM386, but I'm wondering if the power is cut off to pin 6, it renders the chip useless, and Tone and Volume have no effect.

I did this on a previous build using the SDA-P amp from guitarfuel.com that has been mentioned numerious times on this thread. With their circuit, I can do as described above; 1) play thru the speakers on the guitar, 2) plug in and play thru the guitar speakers and an external amp, and 3) turn off their amp, but still use the volume to control gain for the external amp. I can't tell from guitarfuel website if the SP+ speaker output and the JK+ Jack output are connected on the board, and the board on my guitar is not accessible at this time.

I prefer using the noisy circuit because it has tone control, grit, plus I like the idea of building it myself.
Thanks for any assistance you can offer.

• ▶ Reply

Permalink Reply by Warren on April 8, 2010 at 12:13pm

Here's what my Little Gem sounds like on "clean" setting (playing is not great, but you'll get the idea of what the amp sounds like):
http://www.cigarboxnation.com/video/first-cbg-build-license-plate

• ▶ Reply

• ‹ Previous
• 1
• 2
• Next ›
• Page