boss tone

[Andy]

My uncle gave me this little box that plugs directly into music instuments.  It's called a Boss Tone.  It has two knobs on top for volume and drive.  I took it apart to see what its like and it's basically just a fuzz clone.  ONe sili-tranny, one germ-tranny and four resistors (maybe more stuff..can't remember)

anyway, is there already a schem online for this exact device?  Would it be worth my while to practice my skills at reverse-engineering it and making a schem myself?  

I just want to give back to the community what I've been given so many times!!

[phillip]

The Jordon BossTone is a pretty neat little device.  From what I've heard, it's not at all a subtle fuzz.  It has a pair of silicon transistors...2N2222 NPN and a 2N3906 PNP.  Here's a schematic from my site:



Phillip

[Doug B.]

My uncle gave me this little box that plugs directly into music instuments.  It's called a Boss Tone.  It has two knobs on top for volume and drive.  I took it apart to see what its like and it's basically just a fuzz clone.  ONe sili-tranny, one germ-tranny and four resistors (maybe more stuff..can't remember)

anyway, is there already a schem online for this exact device?  Would it be worth my while to practice my skills at reverse-engineering it and making a schem myself?  

I just want to give back to the community what I've been given so many times!!

Andy -

Often times we encounter production variations on a device, and sometimes the schematics floating around the web have inaccuracies.  (Sometimes even the original manufacturer schematics have errors!)  The original Boss Tone schems had such a history, but i think they have been corrected.  (Yes?)

Anyhow, i guess i'm saying it never hurts to have confirmation... and documentation of possible variations.  For example, Phillip's schem (above) uses two silicon transistors, and you mentioned a silicon and a germanium.  (I don't recall off hand what the other ones list.)

So why not go for it?  It couldn't hurt!

- Doug B.

[Andy]

In the great words of Monty Burns:  "Exxxcellent"

I will try my hand at this!!!  Maybe even try to make a pcb for this simple circuit.

[aron]

The Bosstone schematic has been in schematics one forever. It's one of the reasons I made this site.

There's a mod you can do to get octave down too.

[idlefaction]

do tell!  how do you octave down a boss tone?

[aron]

Just make the input and output caps 10X bigger. So .2uF for input and output - or larger I suppose.

I used to have sound samples of it too..... hmmmm.... darn tripod!

[LP Hovercraft]

Octave down on a Bosstone!?  That must sound like a primered '72 Chevy Nova with a missing muffler!  I want to try this right away.  Thanks Aron!

[nightingale]

oh man~
our lead guitar is using a JBT clone right now. i might have to sneak into the practice space and trade caps. that circuit takes some expeirmenting with, but he gets very nice tones with it, as i could not.
best,
~ry

[Mark Hammer]

Just to clarify, the "germ-ey" looking transistor is likely a 2N2222.  This one frequently comes in a metal can.  While germanium tansistors come in metal cans, they are not the only that do so.  For instance, BC109 trannies usually do.

[petemoore]

I've got a Ge in Q2 and an extra LED in the diodes socket with the 1N914's l<-->l nice little ckt!!!
 You could probably 'tag on' [parallel extra in and out caps] caps to the existing caps to get near the value you're looking for if that seems easier for hard wiring or switching bigger values there.

[Andy]

http://mywebpages.comcast.net/thephantom/BossTone002.jpg
http://mywebpages.comcast.net/thephantom/BossTone008.jpg

here are some pics of the boss tone.  The number on the round topped transister (i guess that the germ tranny) is 2n4249.  the sili has mps 6513 printed on it.

I can't make out what's on the caps but I am gonna keep at it.

any insight on those trannies?

[Doug B.]

http://mywebpages.comcast.net/thephantom/BossTone002.jpg
http://mywebpages.comcast.net/thephantom/BossTone008.jpg

here are some pics of the boss tone.  The number on the round topped transister (i guess that the germ tranny) is 2n4249.  the sili has mps 6513 printed on it.

I can't make out what's on the caps but I am gonna keep at it.

any insight on those trannies?

Andy -

Thanks for the pictures and identifying the transistors -- these sound like different devices than have been previously reported for the Boss Tone.  

I don't have a data reference handy right now, but i doubt that the 2N4249 is a germanium, even though it *does* look different  than the typical silicon  transistor -- i don't think they made germanium devices with numbers that high.  But i'll check when i get home.  

As for the MPS6513... sometimes manufactureres stick their own codes on the front of the device number instead of the "2N".  But that would make it a rather late device, so i kinda doubt it was a 2N guy.  ("MPS" is a Motorola code, i believe.)

Any clues about what year this particular unit was manufactured?  (Pot codes, for example?)

- Doug B.

[Andy]

the only thing I can find on the pots are on the knobs and they both have crl b16-121 b9 on them

[Ammscray]

The 2N4249 is a PNP SILICON device according to my Motorola book, which my original pedal has...and FWIW it also has an MPS6519 device in it, not 6513...the later knock-offs made in Nashville or TX or wherever (orient) have much different trannys with nebulous numbers but still sound really good!

Awesome with a clean amp but way too over the top with a naturally distorted tube amp cranked...

[Peter Snowberg]

http://www.mouser.com/index.cfm?handler=search.listcategory&Ntt=+512-MPS6513&Dk=1&Supplier=Supplier&D=+512-MPS6513&N=0

The 2N4249 is not current production, but there are a lot of them out there is seems.



-Peter

[Andy]

The 2N4249 is a PNP SILICON device according to my Motorola book, which my original pedal has...and FWIW it also has an MPS6519 device in it, not 6513...the later knock-offs made in Nashville or TX or wherever (orient) have much different trannys with nebulous numbers but still sound really good!

Awesome with a clean amp but way too over the top with a naturally distorted tube amp cranked...

yeah, the back of this says music city mfg.co. nashville  is this a second generation or something?  its from the seventies according to my uncle

[Ammscray]

The 2N4249 is a PNP SILICON device according to my Motorola book, which my original pedal has...and FWIW it also has an MPS6519 device in it, not 6513...the later knock-offs made in Nashville or TX or wherever (orient) have much different trannys with nebulous numbers but still sound really good!

Awesome with a clean amp but way too over the top with a naturally distorted tube amp cranked...

yeah, the back of this says music city mfg.co. nashville  is this a second generation or something?  its from the seventies according to my uncle

I do know a few people who claim they bought their nashville units in the late 60's new but who knows...there was yet another one a bit later too, so 3 in all that are in the same case with no (case) differences except for the label, which is not aways on the back to tell you what model you have...gotta look inside...and again they all sounded good...

Interesting tranny observation I just made...my motorola book has both the 2N4249 and the MPS6519 listed as PNP devices...hmmm...and BTW the MPS6513 is a very low gain NPN device...

The MPS devices were just later-issued versions of popular 2N numbers, and they put them in the TO-92 case style (that were previously in the TO-98 case) and for some reason changed the designation of some of them to MPS...I've been told that the company that bought out Motorola's component division did this but I don't know for sure...

 Motorola and G.E. made most of the 2N numbers and IMO they're the best ones, although later Philips are excellent too, as were National Semiconductor...fairchild not so good...

 The same thing with the PN-designated devices, such as the PN3565, being the modern eqiuvilent to the older and hard to find 2N3565...in my experience the MPS devices are all excellent but the PN's suffer in comparison with the originals in the TO-98 case style...I love when I come across those!

[BillyJ]

While germanium tansistors come in metal cans, they are not the only that do so. For instance, BC109 trannies usually do.

Yep I just got a handful of BC107 thinking I might have scored.
They sure look cool :O)

[Doug B.]

http://mywebpages.comcast.net/thephantom/BossTone002.jpg
http://mywebpages.comcast.net/thephantom/BossTone008.jpg

any insight on those trannies?

Here's the only specs i could find on the two transistors (from a chart):

                              MPS6513:         2N4249:
                              --------------         ------------
 material:             silicon               silicon
 polarity:               NPN                   PNP
 outline:                TO-92                170F
 leads:                  E B C                 E B C
 Vce:                     30 V                    60 V
 Vcb:                      40 V                   60 V
 Veb:                     4.0 V                  5.0 V
 Ic:                         100 mA              -
 Pd:                       310 mW           200 mW
 Freq:                   250 MHz            40 MHz
 Icbo @ Vcb:        50 nA @ 30 V  10 nA @ 40 V     (leakage)
 Hfe @ Ic:            130 @ 2 mA     280 @ 10 mA     (gain)
 manufacturer:   Motorola            Fairchild

From: Transistor Specifications Manual, The Howard W. Sams Engineering Staff, Howard W. Sams & Co., Inc., 1967.

So both of these guys were around by 1967, and in all likelihood, a bit before.  This would be about right for the original Boss Tone.  (Anybody know when it first hit the market?)  

I think i read in interviews that Robbie Krieger (the Doors) and Randy California (Spirit) used the Boss Tone a lot.  

- Doug B.