Fulltone 70 Build question

[Craig V]

I've had this around for a few months, and it never sounded too great.  Today I took it apart and compared the voltage measurements to the measurements on the schematic.  

On the Germanium diode, I measure 0 volts.  I have been looking at the schematic and it has a cap on one side, and is connected to ground on the other side.  I don't see how any voltage should be there.

Does this happen to anyone else's?  The schematic calls for .226V.  

The rest of the measuremnts are fine, and the transistors are biased at 5.5V.

Thanks.

[petemoore]

Big Bouncy FF. ..FT70.
 I don't have the diode in it though.

[phillip]

I think that .226V is actually where he used the diode test function on a DMM to test the voltage drop of the diode to see if it was a Si. or Ge.  With that capacitor before it, there shouldn't be any DC voltage on it since capacitors block DC voltages.

Phillip

[Dai H.]

I modified my Si FF according to that schematic, and I like it. The specfic transistors still seem to make a difference though. The high notes are thick and sort of synthy on mine.

[Luke]

"I think that .226V is actually where he used the diode test function on a DMM to test the voltage drop of the diode to see if it was a Si. or Ge...."
Phillip"

Yep, Phillip is correct.
Luke

[Craig V]

Thanks for the replies.

Are their any sound clips floating around of a DIY FT70?  I'm still not sure mine sounds correct.  It sounds a lot darker and smoother than the clip on the Fulltone site.  It's kind of like I strike a note, then hold it and add vibrato then the sound sort of blooms.  Should this be happening?  It doesn't seem to have as much output as my Ge FF either.

[Mike Nichting]

In my opinion there isn't a Fulltone pedal worht owning~!!
Thayts just my opinion. I have owned every one of his/her pedals.

[Kleber AG]

I breadboarded it but it sounded weird for me (IMO), I don't know why, probably my falt with some bad tranny or part, it was a very fast try at the breadboard...  until I started another circuit on the breadboard.

I think that Doug H. could give us some comparison (please Doug) between FT70, AXIS, HotSilicon, whatelse? I remember tha he tryed these ones...
Doug? I would really apreciate some comparison opnions...

Thanks
Kleber AG
BTW: I like the HotSilicon.

[bwanasonic]

In my opinion there isn't a Fulltone pedal worht owning~!!
Thayts just my opinion. I have owned every one of his/her pedals.

I simply ador my Supa-Trem. It's build quality is outstanding, and it is a versatile and great sounding pedal. I know a lot a people who really like their FD IIs, but I have never tried one. I would like to try a Clyde wah.

Kerry M

[Mann]

Is the schematic for Fulltone 70 / 69 available anywhere?

[petemoore]

I put a front end buffer on this one today, replacing an LPB 1 one a bypass switch I had there
 More defined bass and more crunch like a ... well alot like 3 transistor Tonebender...
 To use same PS as the FT, Ill have to convert the Buffer [PNP using NTE158], to NPN ckt...probly jsut make another one instead though...EZcheep...any type transistor buffer would probly do the trick, just as good and not too different? but I had that GE laying right there and popped it in a ckt.

[Doug H]

I breadboarded it but it sounded weird for me (IMO), I don't know why, probably my falt with some bad tranny or part, it was a very fast try at the breadboard...  until I started another circuit on the breadboard.

Double-check your Q2 collector voltage and make sure you have it biased right. I used motorola metal-can 2n2222's and they sounded really smooth. Lower hfe transistors sound much better with this thing.

I think that Doug H. could give us some comparison (please Doug) between FT70, AXIS, HotSilicon, whatelse? I remember tha he tryed these ones...
Doug? I would really apreciate some comparison opnions...

Thanks
Kleber AG
BTW: I like the HotSilicon.

To me the FT70 sounds pretty similar to a typical fuzz face. It is a little more aggressive with the Si transistors (compared to Ge) but the diodes smooth it out and make it sound more refined. In addition it has that "violin tone" to me, kind of hard to describe, but thick and tight, reminds me of the sound of my NPN Boost on the "thick" setting. In the end, it sounds like a very "refined" fuzz face to me.

The Hot Si is a Tonebender Mk2 derivative. It has more of a roaring, ballsy, and gainy sound than a Fuzz Face. Tonebenders sound really "big" to me compared to Fuzz Faces. It doesn't clean up as well as a Fuzz Face, but it still cleans up pretty well. The high gain tone is to die for, IMO.

I just breadboarded the Axis again and I am starting to change my opinion on it. http://www.diystompboxes.com/sboxforum/viewtopic.php?t=16101&start=15

I've changed my opinion more favorably even since that post a few days ago. I played with it again last night and I think I'm starting to really like this one. I've never used something that made the full travel of my guitar volume pot so usable. I was dialing in really -good- and loud overdrive sounds with my guitar volume on 1.5-2 (yeah -really- low), then cranking it up for good fuzz tones around 5-7 then maxing it for over-the-top swells, octave feedback, and freaked out tone. It is definitely in it's own universe when it comes to fuzz tones, very different from anything else I've tried.

I hated it at first because of the "freak-out" tone, but realized if you play with your guitar volume you can find some really nice fuzz tones and a wide variety of different sounds in general. When it's cranked it responds better than any other fuzz I've heard (so far) too. It's really easy to coax octave feedback and other fun noise out of it. But it's like riding a wild horse, you have to tame it with your volume control to make it really usable, IMO. Once you learn that, you can use it -very- expressively. But don't bother with it if you're not going to play around with your guitar volume with it.

The overdrive sounds on it are very nice too. Either lowering your guitar volume or the fuzz control (which is very useful BTW) will get you a nice "vintage" overdrive tone that blows away tube screamer stuff IMO. Listen to the rhythm guitar parts on Band of Gypsies and you will get the idea. I'm pretty convinced Hendrix left that axis fuzz on most of the time and controlled it all with his volume knob, it seems to nail that low-drive sound he gets. I think it blows away the fuzz face "cleanish" sounds you get by turning down your guitar.

It's hard for me to compare these things though. They are all different with their own advantages and disadvantages. I've already got a fuzz face and tonebender derivative so I'm not in a big hurry to build another fuzz right now, esp since I'm doing some amp stuff. But when I get around to doing another fuzz, the axis is at the top of the list, mainly because it is so different than anything else I have. But the FT70 sounds really nice too, just not different enough from a FF for me to go to the trouble right now, but I will eventually get around to it.

Doug

[Kleber AG]

Thank you very much Doug.

I think I'll breadboard the AXIS so soon...

Thanks  
Kleber AG

[Doug H]

Thank you very much Doug.

I think I'll breadboard the AXIS so soon...

Thanks  
Kleber AG

Ammscray and some others recommended subbing the 47k feedback resistor with a 27k. I tried that and like it a lot. It gives it a wider range of tones with the fuzz control and still more than enough gain when you dime it. They also recommended avoiding the fairchild transistors if you can and using older ones if you can find them. I used a motorola metal-can 2n2222 for Q2 and like that a lot. It has the same hfe (190) of my fairchild 2n3904 but sounds a little smoother.

One more thing, plug this in your tube amp and crank it. It's not for the SS amp at bedroom volume. Just like a fuzz face, it likes a little amp dirt and will sound better and respond better in that situation.

Doug

[bwanasonic]

I hated it at first because of the "freak-out" tone, but realized if you play with your guitar volume you can find some really nice fuzz tones and a wide variety of different sounds in general. When it's cranked it responds better than any other fuzz I've heard (so far) too. It's really easy to coax octave feedback and other fun noise out of it. But it's like riding a wild horse, you have to tame it with your volume control to make it really usable, IMO. Once you learn that, you can use it -very- expressively. But don't bother with it if you're not going to play around with your guitar volume with it.

This pretty much sums up the *beauty* of a good fuzz. A lot of people never get past that *freak-out* tone and miss out on the range of tones available with just the guitar's volume knob. Never mind those who plug their EMG equipped guitar into a fuzz and plug into a solid state practice amp, and then wonder what all the fuss over these pedals is about.

Kerry M