Boss OD-1 Clone 14 pin op amp

[ScienceFriction]

You'll probably do a much better job than me Earthscum, lol.  It would be interesting to see how our two pedals compare, I'm glad I'm not the only one who thinks this is a cool project.  Actually, I wonder how a distortion would sound with a 14 pin op amp instead of an 8.  It's weird how the 14 pin op amp just came and went so quick, but has retained it's interest.

[Mark Hammer]

I might try this, too.  I have some 1S1588s sitting around that Osamu Hoshuyama was kind enough to give me some years back, and I have a 3403 now sitting in a piece of foam awaiting deployment, plus some spare boxes.  Maybe an evening project.

[zombiwoof]

You'll probably do a much better job than me Earthscum, lol.  It would be interesting to see how our two pedals compare, I'm glad I'm not the only one who thinks this is a cool project.  Actually, I wonder how a distortion would sound with a 14 pin op amp instead of an 8.  It's weird how the 14 pin op amp just came and went so quick, but has retained it's interest.

I'm sure the change by Boss from the quad opamp to the dual opamps was driven by economics, it was probably just cheaper to use the duals.  I think that's why the 14 pin opamp "just came and went".

Al

[ScienceFriction]

I think it's weird how it's retained some mystic, but I guess that's because of it's sound.  I know most companies change things because of price, but I wonder how much extra it cost Boss to use the 14 pin op-amp.  I guess small changes can really add up over thousands of pedals.

I'm still waiting on my components, so I haven't started work yet.  Small Bear Electronics suggested that I ask around to see if anyone can do a PCB etching for the Boss OD-1 that I'm cloning.  If anyone knows if anyone has done something like that, or would be willing to please post.  However, would it be possible to work off a DS-1 or SD-1 etched board?  I am beginner so I probably don't want to go trying things that are too complicated at this point.  Thanks.

[ScienceFriction]

Will I get in trouble for a double post?  I hope not.  Just a quick update.

I got all of my parts today, I had to wait on some extra diodes from diystompbox (I gave myself as many options as possible.. but I still want to get some of those Mosfet ones).  Now if I understand correctly, I still need to go get some metal wire for the breadboarding, right?   I need some new wire cutters anyway, so I might just go pick that stuff up tonight.  I've got a tone of the 14 pin Raytheon IC's, so I've been considering cloning the Boss DB-5 as well, which used two of the Raytheon IC's.  Seeing as GodiksenNet.com has what appears to be all the info I need schematics.  I'm not going to take on two projects at once, but after I finish the OD-1 I want to attempt the DB-5 and compare them.  Besides, I've always thought the DB-5 sounded awesome.

[OldIron]

Hey guys.

I'm about to start this project too.  I should be getting some of the original 14 pin op amps in the mail in a couple weeks.

What is the story on the two diodes used in the 14 pin version?  In the Japanese schematics made by Japanese cloners, I see the 1s1588.  In US schematics I see 1S2473.  But these schematics are either hand drawn or from a service manual for the 8 pin 4558 version.  I have not been able to locate a service manual for the older 14 pin version that has the diodes part number on it.

Is it possible that the first versions were made using the 1588, and it was switched to 2473 when boss changed to the 4558?  Or have they always used both depending on what the stock was in the factory at the time?

http://www.hobby-hour.com/electronics/s/od1-overdrive.php


I looked at the datasheets for both diodes and they look to be about the same.

                                          1S2473                 1s1588
Peak Reverse voltage VRM    40V                      35V
DC Reverse Voltage VR         35V                      30V
Peak Forward Current Ifsm   300 mA                 360mA
Mean Rectifying current Io    110 mA                 120mA
Surge current Isurge            400mA                  500mA
Power dissipation Pd            300 mW                300mW

Forward Voltage Vf.92-1.2 V, at If =100mA     max1.3V
Reverse current IR 0.010-.5 uA, at VR = 35V   max.5uA
Capacitance between terminals Ct 1.50 - 3 pF,  3pf
Reverse recovery time trr 1.5 - 4 ns                    4ns


would the difference in these two diodes contribute to the differences in sound between older 14 and 8 pin models? 

thanks

[bdhact1]

I built the 4558 OD-1 from that schematic. It sounds awesome. I'm next going to build a quad version, Although Analogman says that the only real difference in sound are the capacitors. I'm going to bread board both to hear how much difference there is. difference. 

[Gordo]

I don't mean to be a wet blanket here but I own an original OD-1 and to me it sounds kind of crappy. I purchased it new in 1980 and immediately gutted it, tossed the case and rack mounted it. 

It's one of the reasons I build pedals now, so I don't do something that stupid again. Also involved in the sacrilage was a Maestro Parametric EQ and a Yamaha 1010 analog delay...

Anyway, if anyone wants any gut shots or parts verification let me know.

[bdhact1]

I made both pedals from scratch. The 14 pin sounds 10 times better than the 8 pin; And the main reason is mostly the capacitor values, and a little bit of the IC. I also bought an old Boss NS1 pedal (very cheap) and gutted the diodes from it which are the 1S5188. I bought a JRC 3403AD 14 pin IC from Small Bear Electronics. In the main input line I used Panasonic poly caps instead of Yamato, 1 .047 ceramic, 1 10uf electrolytic and 1 boxed metal film in place of the 1uf electrolytic for more consistancy. It sounded awesome with that combination, and much more alive than the JRC 4558 version. I just wish General Guitar Gadgets made a PCB. It would have been a time save

[askwho69]

very interesting i've read a lot and now i have new knowledge hope someone will make a !@#

[Rectangular]

I think it's weird how it's retained some mystic, but I guess that's because of it's sound.  I know most companies change things because of price, but I wonder how much extra it cost Boss to use the 14 pin op-amp.  I guess small changes can really add up over thousands of pedals.

I guarantee you that boss used those rc3403ab chips because they were dirt cheap, not because they were feeling especially spendy, or because the chips had an amazing sound. its only in retrospect that guitar culture attributes these decisions to being for the sound, rather than cost. these pedals were made during the late 70s/early 80s, back when japanese manufacturing companies were heavily nepotistic; there isn't a doubt in my mind that Boss/roland got some crazy cheap stock of raytheon chips, and decided to use them for a simple overdrive pedal. for japanese electronics from that era, this is extremely common practice.

[soupbone]

Hello, DIY stompbox newbie here I hope posting a new thread is okay.  I'm planning on attempting my first homemade stompbox, and I was hoping I could find some answers and direction here.

I want to make a clone of the Boss OD-1 RC3403ADB chip pedal clone.  I've already gotten my hands on a RC3403ADB chip, but I'm struggling to find the rest of the parts.  I want it to sound exactly like the original, or as close as I can get.  I know stompbox cafe has a parts list, but for example I'm confused by the parts numbers on the Mylar Capacitors.  Does it only matter if the capacitor is Mylar and value?  I have soldering experience, but not electronics experience.  So, does anyone have an idea where I can find the correct parts for this project?  I have no idea where to even find a 1S2473 Vintage Si Diode or Main PCB (35 X 56 mm).

Also, I want to add a tone knob and true bypass to my OD-1 clone as well, would that change the sound much?  I mean, hypothetically speaking, if I didn't use the tone knob I would assume it would sound the same as an original OD-1.  I have an OD-1D with the uPC4558C (NEC), so I have something to use as a guide, but I don't plan on messing with that pedal, I like it.  If anyone could help me I'd be incredibly grateful. 

Have you ever seen this? http://stompbox.cafe24.com/3

[Mark Hammer]

I made a 3403-version unit for myself recently, with mods of course, and while I was unimpressed initially, I've grown to like it.  It's not a where-have-you-been-all-my-life pedal, but delivers a respectable meat-and-potatoes sound.  Sounded pretty darn fine through a Phase 90.

I installed a DPDT on-off-on toggle that is stock in the middle position, adds more bass in side-position 1 (supplements the stock .047uf cap with a .1uf unit), and provides the same bass retention plus some treble rolloff ("rounding") in the other outside position (another cap in parallel with the .018uf unit).  So, it essentially provides the stock, somewhat thin sound, a fuller yet bright sound, and a fuller but rounder sound.

Not having attempted the 4558-based version, I can't tell whether the changes may be as pleasing.  They might be but I haven't A/B'd them.  I suspect that the 2+1 diode complement and the tone stage probably account for far more in the characteristics than any of the other elements.

Having said that, I will point out that the output buffer in the 4558 version is largely identical to the stage used for a Tube Screamer.  Some folks find the use of TS-808 component values in that stage to be more pleasing to them than the TS-9 and TS-5 values.  Conceivably, if one does build or wn a 4558 version, you may want to sub a 100R and 10k resistor on that output buffer in place of the 1k and 100k that are normally there.  It may sound better to you but it may sound identical.

[ScienceFriction]

Hey guys, sorry for abandoning the topic, this project fell by the wayside and got put on the back burner for awhile. I'm still as much as a newbie, all I've got done is the chip is soldered to the pcb, lol. I recently got some 1S5188 diodes so I'm going to try to get this project done. I feel pretty much in over my head at this point though. Though I have ten extra RC3403ADB chips in case I make any major mistakes, lol.

Mark, I know you posted nearly a year ago, but did you ever build a 4558 version and A/B them?

[Mark Hammer]

No.  I have SOOOO many overdrives, that, apart from the little 1-hour things like Pink Jimi's 2-transistor Kustom clone, I stay away from building anything that looks like it might be redundant with what I already have.

I don't know that the 5188s are essential to the pedal, but if you have them, good on you.  Build the 3403 version and enjoy it for what it is - not inspiring or distinctive, but far from useless or bad-sounding.

[ScienceFriction]

I hear ya, I really love overdrives as well. I know that they may not all sound that different, but I can't help but gravitate towards all the different flavors.

Thanks for the reply Mark, I appreciate it. Yeah, I grabbed them when I came across them just to give them a try, I wasn't actively seeking them out anymore. My board currently has a Timmy and MXR Distortion + script logo RI on it, which I think will are good pedals to compare the OD-1. I'm not sure when I'll finish it, after a bad experience with a PCB from an amp I'm hesitant to get to work. I've got to sort all of the values and parts out again anyway.

[ashcat_lt]

According to the scheme above, it's got a pretty low input impedance.  It's like half what you get in the SD1 and low enough to where I'd expect noticeable treble loss with most passive pickups.  This might help some as "pre-shaping" to stop the OD getting real harsh, but since that stage is still in circuit while bypassed I think it pretty much defines "tone suck".  Course, I've never tried one...

[pinkjimiphoton]

No.  I have SOOOO many overdrives, that, apart from the little 1-hour things like Pink Jimi's 2-transistor Kustom clone, I stay away from building anything that looks like it might be redundant with what I already have.

DUDE... i am SO honored. 

[roseblood11]

Is there a veroboard layout for the quad opamp version? I think I saw one some years ago...

[aelling]

Is there a veroboard layout for the quad opamp version? I think I saw one some years ago...

I posted my layout on the tagboardeffects forum not long ago.
http://guitar-fx-layouts.42897.x6.nabble.com/Boss-OD-1-with-Quad-Opamp-verified-layout-tp46394.html