Archive for the ‘Compact Series’ Category

Boss MZ-2 Digital Metalizer

Sunday, March 8th, 2015


What is it?
Boss MZ-2 Digital Metalizer from Boss Compact series. Made in japan, july 1988.

Now, since i’ve lately been looking at these late 80’s analog/digital hybrids, this may be a decent unit to continue with. We are looking at Boss’ take on the distortion plus delay/chorus effects that were widely available back in the day. DOD had it’s own as “Hard Rock Distortion” and Ibanez shuffled the deck with its Session Man pedals. I’m quite sure there were others trying to take the markets too. There sure was i time and demand for this kind of combination back then. While the competition had the delay and chorus lines done mostly by analog methods, Boss aimed for the moon and made it digital, while leaving the distortion part analog.

Once the bottom plate is removed, my reaction was to freeze for a few seconds. Wow. Part of the traces look like good old japanese hand drawn beauty, but the digital signal processor’s small traces try to keep up with the old school design. Those thin, round traces at the right hand side of the DSP look very pleasing.


As with other digital Boss pedals of the era, the mixture of through hole components and SMD parts is in place. In addition to having two separate, stacked boards to accommodate everything. While these combo effects do not interest me all that much, i must say i find this unit very appealing.


What comes to controls, we have our basic three knob layout for the distortion part, including gain/distortion, tone and volume. The digital section has only presets for being off, having couple of different choruses and delays on or off at the same time. Lack of more controls to the digital part feels kind of boring, but the presets are actually quite good. Sadly, i couldn’t find a schematic of the analog board to confirm how the distortion part is made up. I think there may be similarities with other Boss distortions, but there must be something different in there too.

How does it sound?
Very much usable distortion. Kind of like DS-2, but with certain amount of personality thrown in. For the distortion side, this may very well be one rare boss effects with a real personality. They could have offered the distortion part as a separate pedal, but since the modulation/delay can be turned off, it doesn’t matter all that much. For the delay and chorus modes.. Well. If you want the sound of a late 80’s hair metal lead solo for your tapping pleasures, this is the pedal that you really need. It is fun to play around with this. Sure enough, it kicks the living daylights out of the competition.

I’m sort of glad that this type of combination isn’t “in” here in the mid-2010s. This is due to change once someone rediscovers the MZ-2 and manages to make a hit with it…

Boss FZ-5 Fuzz

Sunday, January 18th, 2015


What is it?
Boss FZ-5 Fuzz. Made in taiwan, may 2007.

Since we are on a roll with sounds coming out of digital circuitry, here’s one to add. Some may have wondered why there isn’t a schematic or any hint of a DIY project for a pedal with this reputation. The answer is simple. The code inside the pedal is the thing that makes up the effect. The electronic circuitry is once more nothing else but input buffer -> electronic switching -> A/D conversion -> digital signal processor -> D/A conversion -> electronic switching -> output buffer. There is a Boss branded signal processor that takes care of creating “that vintage up octave sounds”. Sure. The idea of having a Fuzz Face, Maestro FZ-1 Fuzz Tone and an Octavia in a single box is not that bad. Actually i’d call it very tempting.


But there is a “but”. The label on the cover says “COSM”, so at least the digital design isn’t being covered or pushed aside like it wasn’t there. I’m not sure when digital stopped being a selling point in pedals. In the 80’s and early 90’s it was respected to have everything digital. To be honest, i’m not sure if i’m ever going to get interested in DSP. The DSP is very useful and can do great things. For example, think of all the reverb units around. And what about those multi effects that are nothing short of great for bedroom practice sessions. Here’s the “but”. We are talking about digitally modeling three circuits that would have been doable with cheaper set of components as an analog unit. To me, this seems like one of the in-house competitions Boss engineers might have had. Say, who can turn three simple, a few transistor circuits into a current hogging digital design?


These three modeled circuits have been classics for decades and for a reason. The different transistors in Fuzz Face (and same goes for the rest of the trio..) make a noticeable difference and there have been several main versions over the years, since late 1960’s. Nevertheless, these classic effects have their status due to driving the semiconductors to the point where they shouldn’t be driven. What boss did, was to model these digitally and put it on the market. And then there are the results…

How does it sound?
Fz-5 isn’t the worst sounding pedal in Boss catalog. Hell, it isn’t even their worst sounding fuzz. But it is like playing chess with a friend on Nintendo. The three modes are surprisingly close to their idols, but still not close enough. The main difference with vintage analog circuits is the “unreliability”. The one factor that makes a Fuzz Face what it is. Even the best digital modeling can’t calculate the semiconductor behavior close enough to reality. Maybe in decade or two, but not yet. These modelers are not that bad sounding things and someone who’s not married to the analog electronics won’t be able to tell a difference. To sum it up, the pedal offers “close enough” models of three widely used and recognized fuzz circuits. For garage punk guitarists, this is not an option. But for those who want to use a little of fuzz in their home recordings, why not. The fuzzes from this box are a lot better than the ones on most multi effect units of the era. At the same time, it is good and it is bad.

Boss OS-2 Overdrive/Distortion

Thursday, January 8th, 2015


What is it?
Boss OS-2 OverDrive/Distortion. Made in taiwan, january 1996.

I was rather keen on trying this one out. I find the idea of OD and Dist made blendable in a single unit intriguing. This, among with other basic or classic hits as DS-1 and SD-1 are probably the cheapest and most common boss pedals around (sure the number of Metal Zones sold may top everything, but still..), so the money spent versus the fun had was nicely in balance. Before digging any deeper, let’s take a look at the board.


Just as one would expect from a boss pedal that was released in 1990. All the japanese hand craft pointers are already gone and CAD software with auto-routing feature has been in use. Nothing even resembling a visual beauty has not been a part of the board designing process (yes, you can argue that it doesn’t have to be as much as you want).  So no matter what way we look at this, it is just dull looking, but well functioning board. There would have been room on the board to place things differently, but why bother. It’s not like anyone else than some pedal freak/enthusiast will ever be looking at the board from a visual perspective. But let’s look forward. There’s a traced schematic up at FIS. This is where things get a lot more interesting.


The switching and input buffering are per most analog Boss boxes, so nothing of interest in there. After the input buffer the incoming signal is split in two ways. The upper part in the FIS schematic resembles a ProCo Rat with its dual high pass filters and hard clipping. The WTF points go to post clipping filtering. After this filter network, that sort of mimics the filter control on Rats, there’s an buffer stage, followed by a mixer amp that takes care of the mode mixing with a pot called “color”. But we’ll need to back up a bit. The second path from the input buffering was sent to an overdrive stage. This stage isn’t a lot different from SD-1 clipping amp with its asymmetrical clipping diodes in the feedback loop. There is more gain coming out of it and the high pass filter is set lower than in Tubescreamers or Super OverDrives. The output of this clipping amp is then fed to the other side the color pot. The gain setting is the most peculiar thing in this design. It’s a dual (or as some folks like to call it – a stereo) pot with value of 270K that sets the feedback resistor for both sides simultaneously. Rest is just the tone control not completely unlike the one in SD-1 and the output buffering.

So yes. There is some effort in the design. I’d even go to lengths to call some parts of it interesting. Simple, but convincing. Nice design in a cheap package. But then comes the issue.

How does it sound?
Not that great. If we start with the OD side of the color pot, the biggest thing that the sound does is raise eyebrows. Maybe even shoulders. It mid honks its way to the drive-in and leaves you with warm cup of soda and cold fries. But the distortion side of the color pot is the burger. Double cheesed and not bad at all. It sure does remind me of a Rat, but not to the degree where it would be “something alike”. Nope. It’s sleeker in its tone and does not go as mushy. Not a Rat, but not a DS-1 either. Good sounding distortion that goes closer to DS-2 Turbo Distortion range. So overall sound of the pedal isn’t too impressive. But it isn’t bad. These do come cheap, so you might as well get one. Hope you like your soda warm, fries cold and burger delicious.

Boss RV-5 Digital Reverb

Thursday, January 1st, 2015


What is it?
Boss RV-5 Digital Reverb. Made in taiwan, june 2008.

So the Boss RV-reverb line keeps getting duller as it goes further. Can’t help but to compare this to RV-2, which was ground breaking pedal in many ways. First off, the RV-2 was the first compact digital reverb ever produced. Second, the design had some real ingenuity in it. RV-2 has gained its status with its impressive, hard work from the design department, while making things that previously were impossible, possible. Sure it was costly effect to produce. So it was replaced with RV-3, which offered more options by having delay settings. Delays are just simplified reverbs without the vast number of stacked repeats, so adding delay modes wasn’t too big of a deal. It did add to versatility a lot, but while it gained high number of supporters, it still couldn’t touch the original RV-2’s status. Apparently RV-3 got too expensive to manufacture as well and it got replaced by RV-5 in 2002. RV-5 was apparent attempt to recreate the feel of original RV-2, instead of clinging on to multi effect-like feel that was the thing with RV-3.

Opening the box up shows a side of the board that makes me wonder if they were attempting a Guinness world record for number of vias on a compact pedal with a single PCB.


The other side shows couple of dual opamps for buffering and mixing, but the effect itself is just a Boss branded DSP chip. Also note the two crystal clocks. Even though this looks like an elaborate and neat design, the same DSP is circulating for other Boss effects too. Which means that the pedal is pretty much the same as twenty or more other pedals in the series.  Only the code for the DSP is different. The thing that gives me the only real feeling about the board is the “Cheer Time” text on the silk screen layer of the PCB.


As the features go, there are six modes of reverb, including digital modelling of spring, plate, hall, gate and room reverbs. Sixth mode is “modulate” which adds a sort of  chorusey feel to the reverb. Other controls are E. Level, which mixes the clean signal with processed one. Tone, which can be used to cut some highs so user can try to mimic more vintage sounding units. And finally Time, which sets the decay time for each mode. This unit is also built for stereo in and out, so it has more uses on the studio desk than many others that are simply meant to be run with a guitar.

The frequencies are kept well in tact, so this reverb works quite well with all the instruments. We could call it full range device. Not sure if that is too official term, but since it’s not cutting your lows or highs to audible degree..

How does it sound?
Like all Hi-Fi digital reverbs. Even though it gets the job done with flying colors, the amount of lacking personality and individualism is higher than on most tasteless and scentless sounding pedals. All the way to the degree where i would go so far and call it boring. While it is one of the most boring guitar reverbs i’ve ever played with, it’s not that bad. Where the digital design was still rocking in its cradle when the RV-2 was released, that also meant that the deficiencies in that unit turned out to be the strong parts. RV-2 is not a supr dull Hi-Fi device, but great reverberator for folks who want to sound like themselves by adding certain rough edge to their sound. RV-5 does not give you any edge. It works as a reverb and it works well. It has no personality and it has no edge. But it works. In reality, this unit will serve a lot better as a vocal reverb used in the inserts of a mixing console than what it can do with a guitar.

More modern technology doesn’t always add to to better sound.

Boss DF-2 Super Feedbacker & Distortion

Monday, December 22nd, 2014


What is it?
Boss DF-2 Super Feedbacker & Distortion. Made in japan, november 1985.

At first, the DF-2 has a history that is worth mentioning. The unit was originally called  Super Distrotion & Feedbacker, but since DiMarzio owns the name”Super Distortion”, Roland was forced to change the name. Similar thing happened with DOD’s “Supra Distortion”, which was originally also called Super. Anyway. Due to this legal battle, there are two cosmetical versions of DF-2 in the wild. The original with infringing name, was only manufactured for a short period of time (approx. four months) and that version has become remarkable collector’s edition. As usual for Bosses, the manufacturing moved to taiwan in 1989. The circuit had a revision in 1991 when the ACA power supply requirement was dropped. Design was discontinued in early 1994 and later replaced By FB-2 Feedbacker/Booster. There is a schematic for DF-2 floating around the webs, so you should be able to find it if you need it.

Got mine in a trade with usual “faulty” label. The faulty part was just a feature with the (idiotic) ACA power supply not playing nice with the modern standards.


The older japanese board designs are always impressive. Even more so for the complex board designs, such as this one. Just look at the number of solder joints and the acid trip traces in there. Definitely not the simplest circuit we’ve seen. As the fetures go, we have our distortion that reminds us slightly of DS-1, with basic gain/tone/level control. Then we have our Overtone knob. This knob controls the amount of distortion for the feedback one can activate on choice by holding the bypass switch. More distortion for the feedback gives out more harmonic overtones for the rising squeels.


So in essence the unit is a distortion with active electronic feedback that can be activated when needed. It is an idea that was something new and innovative back in mid 80’s. The method how this effect was achieved isnt’ too simple, but it did change something in the mindet of effect designers. Designers weren’t bound by just copying the ten to twenty classic circuits and improve on them anymore. In other words, and in my opinion, these kind of breakthroughs paved the way for all digital effects. Progress isn’t always good or bad. But it is always progress.

How does it sound?
The distortion tone has a similar feel as the DS-1 Distortion, but whilethere may be similarities, the DF-2 has more balls. Maybe it’s just a bit more low end and possibly a bit more gain, but that is enough to sound better, meaner and fatter. When one holds the lid, the rise of the feedback acts very much like standing in front of a Marshall full stack would. So the feedback sounds and feels more organic than one would expect.
This unit sounds like a milestone. Mainly, because it is.

Boss BF-2 Flanger

Wednesday, December 10th, 2014


What is it?
Boss BF-2 Flanger. Made in taiwan. No serial number and no enclosure date stamps.

Even the electrolytic capacitors have no date codes. So it’s nearly impossible to determine the date accurately. My best guess would be 1993, since dual opamp codes point to that direction. The japanese units apparently have all black knobs and the change to white top knobs happened around the time manufacturing moved to taiwan in late 80’s. All the 00’s units i’ve seen have enclosure stamps on the stomp lid insides, but this one doesn’t. I’m going to let myself believe the unit is from ’93 and stop thinking about it.


Board design in on par with earlier Boss pedals. This means that every little part of the design is japanese and the manufacturing only is done in taiwan. There are some of that super cool acidy feel on the traces and no sight of machine routing. It’s a pretty thing, that’s what it is. As a tiny history lesson, the circuit of BF-2 Flanger did take a long time in being a current device. The design was first introduced in 1980 and it discontinued as late as 2001. This and a few other facts are up at Boss Area. Check that out too. The schematic is up at Hobby Hour dot com.


As the electronics go, my unit accepts the notorious Boss ACA power supply only. I’m not sure (and the Boss Area doesn’t say), but i think the later units were modified to be used with more standard-like PSA supply. This means that there is a zener diode dropping the unregulated supply voltage to what the effect needs. There will be issues if this unit is powered with modern standard power supply all by itself. Daisy chained with other – then there’s no problem. Anyway. The buffering and mixing is handled by two 4558 dual opamps. TL072 in some units (IR9022 in mine) is the LFO and the delay line is done with MN3207, a 1024 stage BBD and a MN3102 clock. So yes. Nothing special about it. Makes a great, solid, and versatile design though.

The controls are Manual (affects the LFO operation), Depth (intensity), Rate (the speed of the LFO) and “Res”. “Res” is short for resonance. Or in this case, we get a bit clearer picture of its function if we would just simply call it feedback.

How does it sound?
Very good. This unit is capable of mild chorus and vibrato to near airplane swooshes. It does not do anything special or have a distinct personality in its tone, but it is a very good sounding analog flanger. As a cardinal sin of Boss modulation effects, the rate range could be wider, but even that is better here than it is on Boss chorus effects. A classic.

Boss CH-1 Super Chorus

Tuesday, October 7th, 2014


What is it?
Boss CH-1 Super Chorus. Made in taiwan, november 2001.

At one point i woke up to a feeling. I had tons of effect pedals, but zero Boss brand choruses. That felt extremely weird, as these effects in Boss catalog are usually praised pedals. So what was i to do, bet to get me some. First i scored a CE-3 stereo chorus through auction site listing (i’ve talked about that unit earlier on..) and second, i grabbed this one as used from around here. As usual, i checked the serial number against the Bossarea decoder and checked some facts about the design as well. What do you know. Just my luck. This unit is one of the very first CH-1s to exit the factory with newly revamped SMD board inside. Just a month older, and it would have been the one with a pink label and a MN3007 as a powering BBD.


The original CH-1 was apparently a derivative of CE-2/CE-3, with added blend/mix control and a tone control, which allowed the user to set the audio frequencies processed by the chorus. But since the changes between the old design and this one is pretty huge, i honestly wonder why this wasn’t marketed as CH-2? The changes would have definitely warranted that. But then again. We have DD-2 and DD-3 delays which have the exact same circuit inside, but for some reason the model number was changed. Peculiarities are sometimes fun, but… Everything about the design look even newer than the actual manufacturing date, but i guess that’s to be expected.


At the first look the board looks a bit like just SMD version of the original. We do know that DDBs come in surface mount packaging too. And the long chip could be a CMOS chip to handle the electronic switching. But no. Closer look revels that there aren’t any BBDs present. Just a digital 20K Itri Erso ES56028 echo processor chip.

I haven’t had a pleasure of comparing this against the  previous version. I highly doubt these two sound anything alike. At least the delay line is different enough to warrant this assumption.

How does it sound?
Decent chorus, nevertheless. Mix control is nice addition when we want to dial in smooth and ambient chorus tones. Tone affects the frequencies chorused, rather than the overall tone. Another feature that gives more to the sound than one would think.While all Boss choruses have a great reputation, i tend to see one fault in all of them. The range of LFO speed feels to be always from too slow to slow. Same thing here. If we disregard that, we have good controls and nice chorus sounds. Not  perfect, and i’d still choose my CE-3 over this in a heartbeat every time. If you get one for ridiculously cheap, then get one. I may keep my eyes out if i happen to run into the pink labeled version at some point. Comparison test would definitely be worth a post…

Boss DS-2 Turbo Distortion

Friday, September 19th, 2014


What is it?
Boss DS-2 Turbo Distortion from compact pedal series. Made in taiwan, february 2003.

Probably the best known as Kurt Cobain’s distortion of choice. I had to get one out of pure interest. I sourced all the Nirvana CDs as used ones last spring. Since there are now expanded reissues out of each and every one of those, one can score the original CDs for pennies. Sure there’s some nostalgia in there, as i (and probably half of planet’s population within certain age range) did listen to those records a  lot when i was in school. I think Nirvana’s grunge was the last “boom” of guitar music to reach an audience as huge as it did. Of course there were a few bigger attractions after it too, but nothing as huge (Green Day’s Dookie craze, scandinavian action rock, etc. etc.). Anyway. As i listened through the discography, i felt like it would have simply been the sound of AC/DC-styled marshall stack maxed instead of somewhat puny DS-2. But as the internet lets us believe, Cobain was apparently a fan of Fender amplifiers. And those aren’t exactly known for their powerful overdriven tones, so the sound had to come from somewhere else. Ok, ok. I promise. No more talk about Cobain on this blog. There’s a schematic up at


Modernish traces and the board looks rather full. If we look at the schematic, we find at least four gain stages and as most interesting single feature – no opamps. All the distortion is coming for all discreet design. Two JFETs and two BJTs do create sort of a discreet opamp for the distortion control. In addition of those, we see soft and hard diode clipping stages. The circuit does remind me a bit of the design inside BD-2 Blues Driver. Only remind. The similarities aren’t that notable. As features, we have the standard gain/tone/level setup. Plus something called a Turbo mode. The electronic turbo switch seems to add a lot of punch to the first gain stage. One can use a latching remote switch to toggle the mode on and off.


The electronic and board design, build quality and, well. Everything else is on par with the whole Boss catalog. Not super interesting, but i see nothing wrong with it either. Nice box.

How does it sound?
Like a machine that transforms squeeky clean amp to a Marshall stack with everything maxed (or with all settings louder than everything else). Two modes are for high gain distortion, or even higher gain distortion. With the gain setting one can get rather Marshallesque overdriven tones as well, but the brightest shine is still on when that control is maxed. All the controls have sufficient, usable ranges. The amount of distortion isn’t has high as for MD-2 Mega Distortion, but still high. There is slight overdrive-style mid hump present, which without a doubt a feature. This pedal doesn’t sound bad at all. It sounds pretty much  the same as the guitars on those Nirvana albums.

Boss PH-3 Phase Shifter

Monday, September 1st, 2014

One more Boss before moving on…


What is it?
Boss PH-3 Phase Shifter from compact series. Made in taiwan, april 2008.

PH-3 marks a very first digital phaser in the Boss catalog. All the previous ones, released before the year 2000, were more like all standard phasers from any other manufacturer – BBD based analog phasers. PH-3 introduced couple of quite innovative modes to the world. Basic modes are digital recreations of four, eight, ten and twelve staged phasing. Modes that were next to groundbreaking at the time of release are rise, fall and step modes. Rise and fall modes are also known as barber pole modes. Step mode sort of randomizes the sweep, resulting in unexpected phasing sweeps.

See. The new ideas on this one were so exciting that i simply skipped my normal pattern and ran straight to the features. Getting back to basics.. Board bottom looks like something that i haven’t seen in the compact series before. All  components are on the other side and the second side traces and vias look modern, but still quite new to me.


And once we flip the board over, we’ll have Roland branded digital signal processor. There’s a schematic floating around at Photobucket. To sum the design, there are analog buffers at the input and output. Connected to the mixing amplifier is the AD/DA converter chip. Which is then connected to a DSP and a CPU running at 4.233MHz. In  retrospect, a slightly faster processing speeds than what we’ll find in Super NES. Sure, i’m psyched about the geekiness of the fact. Way more than by the design itself.


Can’t help myself. These computer-like pedals can offer some reasonable tones and sometimes even something completely new. Still i’m left cold and somewhat bored by the designs. It may be just current me talking, but analog designs are the ones where the real magic happens. I see little value for a VST plugin in a stompbox. This stance may change someday. But i’m fairly certain that day won’t be any of the 365 days of 2014 or 2015.

How does it sound?
Like most well designed/programmed pedals of the modern, digital world. These things get the job done without degrading the guitar’s sound too much. Actually, little enough to go unnoticed. The modes are new and exciting addition to the pedal sounds people crave. Even though it sounds good and the old school modeling modes also sound good, there is something missing. It just doesn’t feel like a guitar effect.It feels a lot more like a generic studio tool. Exactly like a VST plugin in a stompbox. Nice thing to play around with. But. Pre 2000 Boss effects are more my cup of tea.

Boss OD-2 Turbo Overdrive

Friday, August 29th, 2014


What is it?
Boss OD-2 Turbo Overdrive from Boss Compact series. Made in japan, march 1986.

The OD-2 was apparent attempt to create a follower for the classic OD-1 which already had a vast user base with lots of hype going for it. In all its simplicity, the OD-1 was pretty much Boss’ venture to kill DOD OD250 and MXR Distortion. Ẃhile it may not be as widely recognized as its older competitors, it’s still a cult classic. And for a reason. The original Turbo Overdrive was manufactured from 1985 and it got replaced by OD-2r in 1994. OD-2r is supposedly the same effect as this one, only with added remote switch jack for the mode switch.

So creating a follower that would sell well and be as recognized as its predecessor wasn’t a simple task. And this is what the Roland/Boss engineers came up with. The board is pretty crowded and it has the feel of the old japan designs.


First thing that you’ll notice is that there are no opamps or any other types of integrated circuits in there. Once again, there is very comprehensive and good page dedicated for this circuit up at  The page has a schematic and a semiconductor listing available. There are three gain stages, each made up with two JFETs and one PNP BJT. Not completely unlike the “discreet opamps” we seen in some designs (the BD-2 blues driver to mind at first…) The gain pot is dual ganged and controls the gain factor for two of these gain stages. The first one acts more like a boost and the second has asymmetrical clipping diodes on it. While the driver stages are pretty complex, at least when compared to very old school like tone and level controls, the wow factor doesn’t end there. Just take a look at the power supply section in the schematic.


There are two different supply voltages which are balanced by transistors, one for buffers and one for discreet opamps. These two supply voltages have their own vref voltage networks, one for electronic switching reference voltages and other for discreet opamp reference voltage. So yeah. It is pretty complex design for being an overdrive.

Well then. How did they succeed in the mission of bringing a successor for the OD-1? Can’t say for sure about the sales, but OD-2 and OD-2r were on the market from 1985 to all the way to 1999. If it had flopped real hard, it wouldn’t have stayed on the catalogs for 14 years. If you mean soundwise?…

How does it sound?
It does have a nice vintage overall feel to its sound. Tone and level controls are well balanced and the gain works pretty well too. Nice driver tones, but with massive mid-honkin’ feel. I’d say this sounds a lot closer to SD-1 than OD-1, without being too close to either one. I’m thinking this may have acted as a base when the engineers were drawing up the BD-2.

Sure it sounds ok, but i just don’t see myself using one for anything. The reason being that i find the OD-1 and the SD-1 to simply sound better.  And there are always tons and tons of Tubescreamer derivatives which can take this sound on any time of the day.