Boss Katana Mini - $2 Mod for MASSIVE Tones 

the feel is different on a proper guitar cab

Handy!

@benmiller03 That's awesome!

@Dexter Morgan I have a Park G10R amp that I'm guessing isn't very different from a Marshall G10 although the R on mine means it has spring reverb. Park is by Marshall but is the cheaper range of amps.

Thanks! We don't have much time to make videos, but it's always fun when we can.

Indeed. For its small size and cheap speaker/components, it actually sounds surprisingly good for what it is.

Nailed it!

Tone Driver SS Thanks for the kind words and support! Do help to spread the word. We have a big hill to climb and the next couple of years will be key for us to keep this thing going.

Try the artist it’s worth it❤

It is! Worth a look for sure.

Imma thinking about the same thing here .

That was just so the video viewer/listener wouldn't be hit so hard by the unexpected volume difference. Nothing to do with the amp.

Thank you :)

A single mono switching jack and some wire. :)

I wouldn't. It's a 7W amp, solid state, so you're really only getting maybe 2-3W of usable/clean power when used with a bass.

Hmmm... Difficult, but doable (theoretically). Since it takes AA batteries, you would have to either: A) Use Li-ion batteries and add a DC jack connected to the batteries in the Katana (that disconnects the main DC when something is plugged in). You'd also have to modify the battery charging station to connect with a DC plug rather than having to plug in the batteries. Voila! OR 2) Find space in the Katana to install the entire charging station and wire it directly to the batteries. I would still use a separate DC jack (switching) to charge vs to power the unit just to be safe. Not easy, but possible.

It's all SMD circuit board stuff. It could be modded, but certainly not easily.

IIRC, the Katana only has a 350mA current draw. As long as the Zoom adapter has the correct polarity and provides enough current (350mA minimum), it should be fine.

@@NextGenGuitars Thanks!

Good question. The setup we had was a condenser mic 6 feet away, equal angle off-axis and equal distance from the stock speaker as well as the 12" speaker. The 12" speaker was loaded into an open-backed cab. The only thing we were concerned with demonstrating in the comparison was the volume difference. The 2x12 with V30s will make a huge difference (for the better). There is no question. Hope that helps!

Thank you very much for your answer! From your video you can definitely tell the volume difference! Besides that, I really believe this small "toy" can deliver much more with the appropriate mods. I am going to investigate myself on the cab emulation because I believe that disengaging it and going through a proper cab will make it sound brutal! \m/ I'll keep you posted!

I wonder if it will be possible to improve the sound by modifying the case or with directly replacing the speaker.... what do you think about ?

​@@metalgarri4194 hello there! Just wondering if you were able to do the mods you mentioned. How did it go?

You can use the stereo jack. You would just ignore the middle lugs and leave them un-used. For the wiring, I wouldn't go by 1:51. It's wired backwards in that shot (edited in the wrong footage)! Disconnect the wires running from the amp to the speaker and connect them from the amp to the common lugs on the switching jack. Then run wires from the other side of the jack to the internal speaker. Voila! Just remember, the tip is positive (+) and the sleeve is negative (-).

Unless the Blackstar has a "speaker in" jack that bypasses the amp completely, you should absolutely not connect the powered output from the Katana to the Blackstar in any of the jacks.

@@NextGenGuitars OK i did the mod, saddly, no sound, with or whitout jack on the socket :(

@@Nixeuss You must have wired the jack incorrectly, or caused some inadvertent damage to the circuit. Best would be to reach out to an amp tech in your area (or online group/forum) with pictures of what you've done requesting advice.

If your truck has an aux-in, you don't need an adapter. There is an 1/8" headphone/aux out on the back of the unit already.

@@NextGenGuitars Could this aux jack not be used as for extension speaker, too?

@@lastdance2006 To go to a powered speaker, yes. The AUX-out is unpowered, so you can't just plug it into a passive cab like we did in this video.

The amp outputs 7 watts at 4 ohms (solid state amp). So, any speaker/cab that is 4-ohm or more with a high enough wattage rating will work fine.

Thanks for the kind words. We're doing our best to change the industry in Canada.

Got my order from you guys today ...Awesome stuff ..This switching jack used for this mod is it just a regular cliff type jack ? & i guess my Katana 100 should be the same type mod ?

Exact same mod. However, the one thing you need to be careful of is that the Katana 100 requires an isolated ground, so none of the metal parts of the jack can touch the chassis. Definitely need a cliff style jack for that. If you use a Switchcraft jack, the negative of the speaker cable will make contact with the chassis and damage your amp.

I added an external speaker jack to my Katana 50. Same idea. I put the switching jack in a black plastice box. Ran the existing speaker wiresa to the jack, new wires back to the speaker and screwed the box to the inside of the Katana cab. Looks good and I can put it back to stock easily.

The stock internal speaker is 4-ohm, so anything 4-ohm or higher will work. We used an 8-ohm speaker in this video. You could probably run an effects loop parallel to the delay since it is always on. It would be difficult though, as you would need to solder to the PCB itself.

@@NextGenGuitars tnx for the info

😂

Any 1/4" switching jack would do. This is the one we used in the video: nextgenguitars.ca/products/generic-1-4-mono-switching-jack-4-lug-solder.html

The audio jack sends audio only. It requires a powered speaker. This mod allows you go use the amp's internal power amp to power a separate/larger speaker (like a traditional guitar cab).

The same process would apply to literally any combo amplifier. You just need to make sure the impedance of the new speaker matches. It could be higher, but you definitely don't want it lower.

Next Gen Guitars the katana air has two speakers. Would they both need separate outputs or is there a way to combine?

That would be fun!

Having not seen the schematic or the inside of one, I couldn't really tell you. That would require a little more in depth investigation.

This video was to demonstrate the potential of the Katana Mini's onboard preamp and power amp. If you have another amp handy, you could run a 3.5mm to 1/4" cable from the "phones/rec out" into the effects return of that amp (or directly into a power amp). However, the "phones/rec out" has built-in cabinet emulation, so it wouldn't be ideal. Thanks for watching!

The backing track in the beginning section is an original tune. All the other guitar parts/demos are improvised.

@@NextGenGuitars SO, i very like your improvised track :), standard tune i think ! Give me the tab plz :D :D

I think it was the Eminence Governor.

Lol. You'll lose your warranty either way.

@@NextGenGuitars I'll switch back to stock and take it up if there's a problem😋 . But is the impedance of the amp 4ohms ? Thanks for the quick reply 😊

Unless the stock speaker was damaged, I wouldn't see any purpose in that. Wattage is not the same as volume. See our blog on speakers for more info on that: nextgenguitars.ca/pages/whats-new.html/speaker-cab-power-handling-for-guitarists-part-3/

@@NextGenGuitars I run my Line6 Helix into a pair of Katanas. They are ideal as I am tight for space. Only issue is, when the volume is just at that sweet spot, the Katana speakers can start to fart out, I think it is down to the mids but I don't know if it is the speaker or the amp struggling to handle the output from the Helix. I haven't really seen many folks on the Web doing this and nobody has reported the farting out issue.

@@markgilson7404 You'd need to have an amp tech assess the issue in person. If the "sweet spot" is with the volume at or above 5, I would guess the amp's power section is having trouble driving the speaker. Adding the Helix to the mix complicated things. A lot of things can be contributing to the sound farting out. No way to say without messing with your setup in person.

It would take some modification of the schematic, which requires modding the circuit board. Possible? Sure. But tough.

Okey thanks

@@NextGenGuitars can you make schematic of footswicth external for katana mini?

@@agronomis80 No, sorry. Best to contact a tech in your local area, or hit up some amp/repair forums.

Oops! Forgot to mention it. The stock speaker is 4 ohms, so the external speaker needs to be at least 4 ohms. We used an Eminence Governor (8 ohms) in the video.

@@NextGenGuitars awesome thanks!

4-ohm OEM Chinese speaker.

Eminence The Governor. 75W 8-ohm

If both speakers are 8ohms each then yeah

NK Headless. A dirt cheap brand of headless guitar. Not very good quality, but I wanted to try headless without spending $1K+.

For the intro? ... I think it was a Carvin/Kiesel with Dimarzio Crunch Lab 7.

Yeah, I’m betting a Carvin, or Carvin/keisel

Yes. I've done the same mod to a THR. Works, and kicks ass! However, be careful because the Yamaha is stereo, so there are two speakers. The process is a bit more complicated, but it can be done. I found an example here for you: www.mylespaul.com/threads/yamaha-thr10c-external-speaker-jacks.313703/

It's been a while, so I really don't recall. Assuming you have relatively fresh batteries, it would sound the same either way.

@@NextGenGuitars It may sound the same for a little while, but it HAS to drain those batteries faster. It's doing much more work pushing that bigger speaker, thus the db gain. That can't possibly come "free" in the sense of no increased battery usage. That would defy the laws of physics. I have a Tech 21 Deuce Deluxe powered cab, so it can take any line level input and amplify it with its own power. It would be a perfect complement to this --- and no mod needed.

​@@Fatherflot64 The amp is outputting the same amount of power whether the speaker is 4" or 18". Volume is the product of a combination of amp output power and speaker sensitivity (aka: efficiency). 12" guitar speakers are 10-15dB more efficient than a typical 4" speaker. Meaning, when a signal with matching power goes to both speakers, the 12" one will be 10-15dB louder. No additional power required. That's physics. We've got a fun blog post about it that includes some more detailed information and some relevant links: nextgenguitars.ca/pages/whats-new.html/speaker-cab-power-handling-for-guitarists-part-3/ Of course you can use the line out on the Katana to go to a separate powered speaker. Unfortunately, that means you're stuck with the rather terrible sounding cab simulation that is built into the line out of the Katana. You get much more natural sounding results with the mod and going into a guitar cab. It essentially becomes a small solid state head. Mind you, it's a Katana Mini. Decent enough sounding for a tiny little practice amp. But, I wouldn't want to play a show with it. This was just a fun/easy project to share for DIYers. Thanks for commenting. Rock on!

@@NextGenGuitars Thanks for the explanation. I accept your expertise on this. Yes, I had not considered the issue of different efficiencies in the two speakers. It does seem incredibly counterintuitive that the same amount of power is used in driving a 4" speaker and a 12" speaker producing 10-15db more volume. Why would the small speaker, designed specifically for this particular amp be so comparatively inefficient? Is this the nature of smaller speaker magnets? In any case, I do appreciate the discussion and the spirit in which you handle comments.

@@Fatherflot64 Thanks! I love talking shop when I get the opportunity. Of course, there are exceptions, but smaller speakers are generally less efficient than larger speakers. Magnet strength, voice coil gap, and cone mass probably have the most significant impact. If we assume the speaker cones were flat instead of conical, just for the sake of easy calculations, you can tell the difference right away. A 12" speaker has roughly 113" squared of surface area. A 4" one is has less than 13". That's a huge difference (amplified even more if we used the proper conical measurements). If both were moving back and forth at the same rate/power, naturally the one with more surface area will "move more air" (be more efficient). 👍

Yes. But, the method might be slightly different. Would need to see the inside of one to be sure.

Subbed!

@@Mattstiless Thanks man!

There is a headphone/line-out jack on the back. You just need to buy the right cable for it to connect to a mixer or interface.

🤣

Wear it as a hat. It works if you have a good tone brain.

Only if you don't already own a cab. 😉

🤣

Did you change the speaker and if so, with which other speaker? I'm have 2 katana's and thinking about changing the speakers for Eminence Aplpha 4a speakers!

Actually, that's not how it works. The same amp settings connected to a 4" speaker vs a 12" speaker will yield the same battery life. 👍

@@NextGenGuitars Thank you, I learned something new today. I check the internet and you seem to be right. If I understand correctly you get +12 db for the same signal. From what I read the exact calculations would depends both on signal frequency and a speaker design. When I was a kid my walkman live was affected by headsets, but it probably was because of gain settings, should do more research on it someday.

Lol. Screws in from the back. Need a long screw driver.

@@NextGenGuitars I didn't realize there was a little screw in the battery compartment too, haha. That was the hold up :)

Great question! That's a headphones/direct out. Great for recording or going into the effects return of an amp, but it won't power a speaker. Thus, we added this jack so the Katana could be used like an amp head to power an external speaker.

😂

Lol. The point of the video was to demonstrate the difference in volume. We didn't bother adjusting the tone, which would be easily adjustable as desired. 👍

There isn't really a way to increase the power. If you need more power, you'd have to get one of the higher watt versions.

If you used the new speaker output to plug into the input of the karaoke box, you'll potentially damage both the Katana and the Karaoke box. If you're going into a Karaoke box, you'd want to use the 1/8" headphones out and run an 1/8"-1/4" cable to the input of the Karaoke box.

It's a tiny analog practice amp. Set expectations accordingly. 👍

Lol!

😂🤘

That's freighteningly accurate considering how socially awkward I am. Lol

That's why it's always best to find local sources. Or, bundle larger orders to get the best value out of the shipping costs. If shipping costs $15, that's because it costs $15. That's not "theft". Get mad at shipping carriers/couriers if you think it's too expensive. Don't throw around crude/inaccurate accusations of "theft". Point your disappointment in the right direction. All the best! 👍

The space in the box (and the port) are part of the design. A speaker and the box it is in form a system. You can take a speaker with relatively poor bass response and design a box around it to either extend the frequency response, or increase the amplitude of the low end. The bass response is determined by how the two (box & speaker) interact/vibrate together.

@@NextGenGuitars correct. . .

Same here. The internal speaker died after roughly a year of not even regular use, and never turned up past half. Very disappointing.....

If you dial the time all the way down and the level all the way up it will work as a reverb! ;-)

Could just pair it with a Reverb pedal and boom. All the effects of the 50w basically

If you work the dials you have a sweet reverb.too easy.

Lol. I'll take it!

Self-deprecating sense of humour.

...and $400 for CAD market. 😂

To be fair, we made no attempt to make it sound good. We mic'd it up at equal distance to compare volume levels only. It's the best sounding battery powered mini practice amp I've ever had, in its price range. Though, the competition is pretty slim so that's not necessarily saying much. 😄

Lol. What? Nothing is faked in this video. I still have the modded Katana amp at home. Still works. 🤷‍♂️

That's because of how it was mic'd. Not to demonstrate tone, but the volume difference between the two.

The speaker it came with was 4 ohms.