Your Boss HM-2 sounds bad and broken? Here's why and how you can fix it! (The Chainsaw Files)

[@martinclark1608]

Thank You! Running an HM-2 with a 9V PSU thinking it was broken. Change to 12V and there we go :)))

[@EvilBlakey]

Wow! Using the correct power requirements for a pedal!? What an amazing mind-blowing trick! I would never have thought of that!

[@DomeNightbearer]

My friends call me "Cpt. Obvious" for a reason 🙂

[@EvilBlakey]

@@DomeNightbearer Cheers :D Seriously though, I really enjoy your vids. I'm looking forward to the HM-2w release. Any plans for more chainsaw bass videos?

[@DomeNightbearer]

I tinker around with some ideas. Maybe for a couple of "Stacked" episodes

[@KYLECULT]

Cheers, man! I found my ancient HM-2 in a box and was planning to add it to my pedal board. I was using a 9v and thought it wasn't working. I was about to bin it until I did a Google search and found your video. Switched it up to 12v and it sprang back to dark metal life! Your advice is much appreciated.

[@DomeNightbearer]

Glad I could help 😊 Enjoy the chainsaw ride 😉

[@shanel4348]

Awesome video for people who don't know this! I had to learn this the hard way myself!

[@JawedKarim763]

😂 I just got my Japanese HM-2, used it with a 9 volt adaptor and was wondered why it sounded like ass, no matter what I tried with my amp settings. Thank you for clearing things up!

[@manualofalternativemusic]

Great video! The world needed a video about how to properly use the hm-2 or any other vintage 12v boss pedals. I had to go search in forums back in the day when I got mine 😅 this just condensed all useful info in one piece of video. Thanks bro (;

[@gnsheehan]

Thanks! I thought I had a glitchy pedal. This was very helpful.

[@MrTimjm009]

Very interesting . Im wondering how it sounds different through a 12 v versus 9v adapter and yet a 9v battery sounds good ( as with the 12 v adapter setting ) ?? Seems to defy the logic

[@414deathmetalist]

If you have a multi power supply and don’t want to risk your HM2 using 12v, some multi power supplies have 9v 500mA options designed for vintage pedals vs the standard 100 mA option that causes the issue for the HM2

[@robertkorn]

The extra current will make no difference, it needs the 12V.

[@414deathmetalist]

@@robertkorn I’ve used a 500 mA power option for a 1984 MIJ HM2, worked just fine

[@robertkorn]

@@414deathmetalist unless your pedal has found a way to defy physics, the more likely answer is that it was PSA modded at some point, pretty common.

[@414deathmetalist]

@@robertkorn how does the original adapter that was only 9v, for a 9v pedal, defy the laws of physics? How does a 9v battery defy the laws of physics? Any boss forum would tell you the issue with the new adapters are the current not being strong enough, not the voltage. Ever heard the saying “It’s the current that kills you, not the voltage”?

[@robertkorn]

@@414deathmetalist Look, this is clearly beyond you but I'll do my best to explain. The power adapter has to pass through a dropping resistor and diode, these were designed to use an ACA adapter which is an unregulated 12V. The resistor and diode drop the voltage to 9V internally in the pedal. The battery bypasses the resistor and diode and supplies the pedal the 9V. You cannot plug a modern 9V adapter into an ACA pedal, this is all very well documented. A higher current adapter makes zero difference, the voltage is still going to be too low. The only way it works is if someone modded the pedal, which is the likely reason why yours works. Don't believe me? Read it here. bossarea.com/boss-aca-adapter/

[@pillbilly8761]

Thank you so much for this video, I got my pedal and felt disappointed and was about to return it. I was using a 9v power supply

[@OfficialAbyssRecords]

Thanks for the tips but if you look at the original paperwork it says 9v on it? However works when in same power line as tuner but not if separate like you mention in video.

[@pyromaniacrandy1319]

非常感谢。我之前刚使用hm2的时候，就遇到了这个问题，但我没管它，直接放了一块电池进去，一直使用。现在我知道该怎么做了，感谢！

[@ThrashingBasskill]

Lol, you look so happy in your video! Enjoying your new living space I guess?

[@DomeNightbearer]

apart from some difficulties I have to rely on 3rd parties you are right :)

[@triceratupuz]

these tricks are valid for all the boss pedals with ACA supply, not only hm2

[@um3899]

only a German mit der Putzfimmel would be embarrassed because a broom handle appeared in an otherwise antiseptic shot lol

[@Yats6417]

Great and informative video ! If I had to choose one method powering a pedal between the two, which would be choosing between a 9/12V power supply or batteries, which one would be preferable ?

[@DomeNightbearer]

I don't know if I get the question right, but you can daisy chain as many other pedals as you like, the hm2 will still work

[@Yats6417]

@@DomeNightbearer Sorry for not being clear :P I have to power a singular pedal, would it be better to do it through a power supply of the correct voltage or would it be better to use a battery of the correct voltage or does it have no impact and is just a matter of preference ?

[@DomeNightbearer]

Ah, I see. No difference although reaaaally old pedals tend to prefer batteries more.

[@Yats6417]

@@DomeNightbearer Okay, thanks a ton !

[@Prestapaganini]

Great video, thank you very much, I didn't know this, I thought my HM 2 was useless, I appreciate it a lot, brother......

[@spuuuuuz]

Man, you GOTTA play some Dismember riffs in these videos. Actually, I'm just secretly hoping you'll actually play Override..

[@DomeNightbearer]

I try to keep it as copyright-claim-free as possible 😅

[@spuuuuuz]

@@DomeNightbearer probably a wise move 😂😂

[@riffsnoleads]

Probably the most annoying aspect of old Boss pedals. There is a mod that can be done that is non-destructive. Just requires putting a couple of jumper wires in, similar to a circuit bend mod. CS Guitars did a video on the HM2 that kind of explained why older Boss pedals are designed this way.

[@akminid]

Nein! Sieh mal einer an, sehr interessant. Das ist in der Tat hilfreich. Ich hoffe, das rettet mindestens einem, der sein Original HM2 auf verzweifelter Internet-Suche nicht aufgeben möchte, weiter. Edit: Freue mich schon total auf das Waza-Craft! Das wird mein erstes Boss Pedal. Ich hatte Freude mit dem Eyemaster damals und nun mit dem WURHM.

[@hysteresis]

I purchased an HM-2 Made in Japan and the guy sent me the adapter he has been using which is a 9V adapter. It works fine. Is there any chance the pedal got modified? I also tried it with my 9V daisy chain without any other pedals, it still works fine.

[@DomeNightbearer]

Maybe there is an adapter, but it seems to me that it is modded... however I might be wrong

[@4rkham]

Have you compared the sound with the sound when running the pedal with a battery? If there is no difference, I'm guessing the pedal is modded. You can open it and check if resistor #2 and diode #1 have been replaced with jumpers (that's the 12v-to-9v-mod).

[@robertkorn]

It's possible it was PSA modded, it's a common easy mod on Boss ACA pedals.

[@hysteresis]

@@4rkham No, there's no difference with the battery. Thank you for your answer. I don't think I can understand the mod since I am not familiar with the electronics.

[@krimsonlediable]

Sehr geil gemacht.

[@xvor_tex8577]

I'm thinking of buying an HM-2 but I have a Orange Micro Dark Amp and a PPc212 Amp, would it still work on my Amp?

[@DomeNightbearer]

Of course it will work. Wether you like the sound or not is a matter of taste. I for instance don't like Orange Amps 🙈

[@metalfan846]

@@DomeNightbearer orange amps take pedals incredibly well, in my opinion the hm2 can't sound much better paired with one. But that's understandable, they don't have nearly as much tight gain as say a Peavey

[@metalfan846]

It will sound excellent but it doesnt have to be an hm2, the eyemaster of lone wolf fx or any kind of clone will work as well

[@dumbamerica]

Yes, it will sound chainsawesome, especially if you use the greatest pedal in the universe, The DOD FX56-B Super American Metal!

[@yburyman9130]

I have a dark. Its grate at handling all the extra drive. But I use a Arion metal master over a clean sound so idk.

[@bulldogavenue]

9v works fine but you need 300ma. That’s what the Boss ACA adapter provides. 100ma starves the pedal of power.

[@maxhellhammer3325]

Does it matter if the 12v output is 300mA or 500mA?

[@DomeNightbearer]

nope

[@Mafangoolio]

Man what a great help!

[@thefuneralparade]

Nice video but I run mine at 9 volt daisy chain at full power and it still sounds like ass.irs because of my amplifier...it's an old ROCKTRON.its distortion just doesn't work with he boss.hm-2

[@DomeNightbearer]

Yeah, some amps don't take the chainsaw very well...

[@bertrandmajorik6589]

BASS player here, a small surgery of the pedal ( removing a cap and a resistor ) could save you an extra power supply, It's on the net. Cannot post links............

[@vb__channel]

Actually, you don't have to remove them, you can just solder a jumper

[@vb__channel]

Here's a link to the guide peperspedals.blogspot.com/2017/07/boss-hm-2-mod-make-it-work-on-9v-power.html?m=1

[@jokinmyass9446]

What I did to my MIT HM-2 is I removed D1 and R2 ( diode 1 and Resistor 2 ) the led was going dim and the pedal wasn't even functioning at times. After the surgery the Led was bright and it's fully powered with a 9 volt supply

[@jokinmyass9446]

And more importantly!!! After removing the components you MUST replace with jumpers

[@jokinmyass9446]

I've also heard you can throw down a fat lump of solder over that area and that'll do

[@Werewolfen]

Daisy chain thing is weird!

[@danmaycock9238]

Gonna run my Behringer HM300 at 12v later, hopefully wont die. Is there a way to notch it up to handle 18v??

[@metalfan846]

The extra voltage won't make it sound better it will just break it, it doesn't work the same way. Please do not try this, the hm300 is adjusted to sound as good as it can with the correct voltage

[@danmaycock9238]

@@metalfan846 Notified 👍

[@metalfan846]

@@danmaycock9238 OK good, please treat your chainsaws with care haha

[@danmaycock9238]

@@metalfan846 Chainsaws need 💙 too

[@robertkorn]

Bad idea, this only works with ACA Boss pedals because they are designed to use unregulated 12v power supplies. Adding extra voltage "just because" is stupid.

[@gtheg130]

thank uuuuuuuuuuu

[@jjrusy7438]

all the people in the comments that think this is a 12v circuit are COMPLETELY WRONG. Nowhere in roland literature do they state 12v pedal. this pedal is so old it is 9VAC. AC has 2 sides to the wave. when you put DC through a rectifier you only get 1/2 the power. 12vdc overloads 1/2 of the rectifier circuit and it almost works ok. who is really that clueless to assume the pedal is 12v anything when you put a 9v battery into it? lol. Just get a 9V battery connector and solder a 9v input jack to it. there is plenty of space to feed the wire out of the battery compartment. Then connect any 9v pedal supply to that and power the HM2 correctly with 9vdc INSIDE the rectifier circuit. this business about needing other pedals is crazy. mis-wiring makes crazy things happen. also HM2 is noisy already, why create ground loops for more noise? i use mine alone often because it is powered correctly. Hopefully you can help clear up this MYTHinformation and people can use the HM2 correctly with no problems or sketchy workarounds. I have owned an HM2 for a long time and i am also an electrical engineer who has always played with musical electronics my whole life, so i looked at the circuit diagram of the HM2 when it didnt sound good with 9v supply and i checked the specs on the recommended boss power supply: surprise: AC supply into AC circuit.

[@jjrusy7438]

Dont mod your pedals, get a 9v battery connector and solder a 9v power jack to it. connect your fake battery to the battery connector inside, thread the 9v jack wire outside the HM2 battery compartment and use any 9v supply. you are emulating a 9v battery INSIDE THE AC RECTIFIER CIRCUIT. the logic used in these other mods is really ignorant and that type of thinking is what destroys music gear. wow and this is the common lore too.

[@the-np4mr]

You sound like a man who messed up a mod in the past lol

[@jjrusy7438]

@@the-np4mr haha, i could see that thought. But actually, not at all. Being an electrical engineer i saw exactly what was going on. my little mod does not physically modify the vintage pedal in any way and maintains its value while actually running it properly. HM2 is old school and requires an AC supply. the rectifier turns the 9v ac into 9v dc. if you put dc into a rectifier, you only get half the power through. that's why people had to go to 12v to ram enough juice through to power the circuit. this is the ignorant kind of thinking that destroys electronics. I do mod things. it's easy for me because i actually know what is happening. rock on.

[@MrJackrockerman]

​@@jjrusy7438any videos of your modding pedals?

[@jjrusy7438]

@@MrJackrockerman no, i'm not interested in mod demos. the hm2 mod isnt really a mod, just a new connection to the battery lead.