Tuesday, 16 October 2012

Astro-Tone Fuzz

I don't know a lot about this other than the fact it seems to be virtually identical to the Sam Ash Fuzz, Analogman sells a clone, and there is an original for sale at the moment on eBay for $3250!  So you can build this if you want to save yourself $3245! :o)

Info about the 1967 original from the manual:

The new Astro-Tone distortion generator is the finest, most flexible, most durable unit of its kind available. One look at the heavy-duty cast housing will tell you that this unit is built to last. The hardest professional use will not affect the Astro-Tone.. The semi-conductors used in the Astro-Tone are all silicon. Many distortion generators still use germanium transistors, not the Astro-Tone. Forget about temperature changes altering the sound quality. Forget about maintenance. Most of all, forget about buying a replacement; you won't need one. This unit will last and sound better than any distortion generator you have heard before.

The Astro-Tone is turned on automatically when a cable from the guitar is plugged into the input. It will stay on until the input is unplugged. This makes it pretty hard to leave on accidentally when you put it away. The output cable simply plugs into the normal input of any guitar amplifier. -There are never any compatibility problems with the Astro-Tone.

The distortion is switched on and off by pressing the button on the face of the Astro-Tone. This alternate-action switch is designed for the hard use of foot-switch service. When the distortion is switched off, none of the three controls have any effect. When it is switched on, each control has a very different effect which makes possible an unusually wide variety of tone colors.

The volume control adjusts only the loudness of the distorted signal and is usually turned up high enough to provide a dramatic increase in volume when the distortion is switched on.

The tone control adjusts the form of the distortion and can alter the tone color of the output signal to mimic the sound of almost any unit on the market. Almost all of the available distortion generators can alter the amount but not the type of distortion which is generated. The great advantage of the Astro-Tone is the control provided over the form of the distortion which can be adjusted from rich to bright. The Astro-Tone provides a wide range of expressive tone colors which can be adjusted to fit the mood of the music itself.

The attack control adjusts the amount of distortion, but not the type of distortion. It is usually left almost at maximum to provide a clearly distorted signal, but may be turned down to soften the sound. If the attack control is turned to zero, no signal reaches the distorter and the distorted output vanishes. To insure enough drive to the distorter, the output of the guitar should always be set near maximum.







58 comments:

  1. I'm on it!!!!

    ----

    Tag.

    Pretty underwhelming. The pricetag on ebay and analog.man's article about this circuit got me really interested. It's not bad by any means. But maybe i was hoping for something bigger. The '67 mushfuzz sound is in there, but does it make it better than, let's say for the sake of argument, Vox Tonebender 1.5 or Companion? If i was a collector with two choices, this in near mint condition for $2000 and Shin Ei Companion in similar condition for similar price tag... I'd probably wait untill either is sold and buy the one that's left. Good simple build. Could probably try bigger in/out caps to get some more dick out of it. Worth a build, but in my opinion, not +$3K.

    I had a hard time tracing the datasheets for the original transistors, but managed to find them. So they should be around 200 hFE for Q1 and 400 for Q2. I used 2N2222A with 212 hFE for Q1 and BC109B with 420 hFE for Q2. These sound good, and this breaks my habit of not mixing 2N and BC transistors in a single build :) 1% metal film resistors and panasonic caps. Look pretty good. Sound also good, but not amazing.

    This ends my report.
    +m

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    Replies
    1. Good stuff mate, well at least you know now so you don't have to buy that one off eBay! :o) I think I've got 200 of the 4003 transistors. They're dome top ones, the same type as the 2N5133.

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    2. That was much easier one to find the sheet for. S1079 took some effort :) But i think anything BJT with ~200 and ~400 will sound close to the original. Might be good platform for tweaking, but still i'm not convinced...

      You should clone a few and sell them for $1K :D

      I promise that next one, how tempting it may be, i'll let someone else do it :D
      +m

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  2. And no. The parts didn't cost me that much :D
    +m

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  3. Holy crap batman! who the hell would pay that! I'd make it just to sell... filthy capitalist attitude :P

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  4. Built this one a while ago and I love it, used 2N4401 for Q1 and BC109 for Q2. It's a simple circuit but it has its benefits. It quickly became a favorite in my band. The TONE control has a great range and with the guitar volume rolled off you can get a lot of different textures.
    Works great with humbuckers and single coils.
    The funny thing is that our lead guitarist in the band is not a big fan of over-the-top fuzzes because he likes to kep the attack and dynamics. He really loved this pedal because it wasn't a fuzz-face style sound and it gave him a lot of flexibility.

    Don't miss out on this one.

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  5. 2sc828's with the leads twisted to the correct spots on the layout sound really great.

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  6. Is it a coincidence that JHS makes an "Astro Mess" Fuzz??

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    Replies
    1. Yes I saw he did a clone as well when I was searching for the vid.

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    2. That's really interesting because there was that whole thing with devi ever accusing him of cloning her hyperion, but that doesn't seem to be the case.

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    3. Kröhm....
      http://www.deviever.com/fx/oldforum/viewtopic.php?f=192&t=13311
      http://www.freestompboxes.org/viewtopic.php?f=6&t=13677
      http://www.freestompboxes.org/viewtopic.php?f=19&t=2181

      For starters, Hyperion and Astro Mess neither do not have clipping diodes...
      +m

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    4. Sorry for double negative. Should have wrote: Either does not have clipping diodes.

      So it still seems to be the case...
      +m

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    5. I'm only doing this because your English is so good that it'll stick with you and so you'll know in the future. It should be "neither has" clipping diodes.

      I'm just impressed you understand double negatives, the only Finnish I know is Litmanen! :o)

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    6. :D I'll try to behave with my grammar in the future.
      +m

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    7. Your English is excellent, better than a lot of English people I know! And I'm not kidding!

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  7. Speak english or die! Nowadays, not knowing english is like being nearly an illeterate. I'm not sayin' if it's fair or unfair, just the truth in modern world.

    I'm lucky because spanish is the second most "powerful" language, and speaking spanish and english you can walk the world.

    The only finish I know is Kimi Räikkönen by the way :P

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    1. The English grasp of foreign languages in general is embarrassing compared to the rest of Europe. Things are getting better and languages are being taught earlier (both my kids were doing basics of French, Spanish and German in nursery and carried on to some extent in primary and junior school), but I didn't do any sort of foreign language until I went to grammar school and that's just too late. The amount of fluent foreign English speakers from the rest of Europe that I come across is staggering, whereas I must have been Spain 20 times and I can just about manage "Please", "Thank you" and "Jug of beer please" :o)

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    2. I tried to study some spanish by myself, and i can read it, but only just. Reason i wanted to learn it was the internet. You know.. There are three languages in the world. Well, four, but i can't think much use for the fourth - as i'm not mail ordering women or trying to buy uranium from the web.. Anyway. The languages are english, spanish and chinese. By only knowing finnish, swedish and english (plus passable or poorly german and spanish) i have only 1/3 of the internet avaible to me. That's just sad. If i knew spanish better, then i would have 2/3 of the world's information on my desk. Add chinese, and the internet is yours.

      It's the telly that does that to us. Sorry, but the Serrano family just isn't that good :) You'll get english on every form of entertainment. And thankfully we finns haven't learned to dub our tv like germans like to do. If you were to be exposed to spanish every day, i bet you would speak it pretty well in six months. But as western world has this vision of monoculture, all of us understand english.
      +m

      Wonder what happened to esperanto...
      +m

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    3. If it's that bad in Europe, I would wager it is just as bad here in the States. I am pretty sure that required language instruction depends from state to state. In my state, students usually get three years of basic language instruction in middle school, but after that, they are not required to take a language. Universities like to see at least two years of a language, but it is really an afterthought.
      Anyway, I speak abysmal Spanish in addition to English. My reading and writing comprehension is pretty good, but I'm a horrible speaker.

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    4. Yikes, that should have read England, in response to Mark.

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  8. Thanks for learning English--Finnish is just too much for most folks!

    I live in a part of the US where Spanish is very widely spoken (hell, we "recently" purchased it from Mexico), but there is very little priority to teach our children even this essential world language. Shame on us.

    My German ain't too bad, but that won't cut it for most applications!

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  9. Hello!

    What could be the effect of increasing the input and output capacitors to 470n (0,47 uf) instead of 0,047uf?
    A bolder sound? An increase in the range of the tone pot?

    Thanks for your answers :)

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  10. I have never tried it but it probably would enhance the gain level of a wider low range and thus tilting the frequency spectrum and make the fuzz muddier and bassier.

    My guess is that 100n would be more or less fine and from that point on you would start to feel the difference. if you are looking for more bass try replacing just the input cap to 220n.

    Nevertheless, it would be interesting to hear what you came up with.

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  11. Well, I was wondering because I'm about to build it and it seems (it seems!) that the Analogman Astrotone (which reportedly sounds like a charm) adopted this solution for obtaining a less thin sound, together with a 470 ohm resistor in the place of the 1k8 tone resistor.

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    1. Larger input cap could potentially let more bass frequencies into the circuit but it's the output cap that will make the biggest difference because it forms a high pass filter with the Tone control.

      With a 47nF cap the tone control will cut lows starting from 287Hz to 1882Hz depending on the position of the tone pot. If you use a 470nF cap that range of frequencies is 10 times lower, 29Hz to 188Hz and so much less lows are attenuated by the filter.

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    2. This comment has been removed by the author.

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    3. In sum this would imply that everything will result more dark... but hopefully not wooly!

      And what about lowering to 470 ohm the 1K8 tone resistor?

      Thanks a lot, I've posted a link to a good thread, down in the post queue ;)

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    4. If you lower the resistor to 470R you'd cut more lows so it would end up sounding thinner.

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  12. I built the Astro Tone as original Sam Ash was and it sounds very good and balanced. In fact in a band setup the Astro Tone sounds much better then many of the fuzzes I have built in the past.
    I don't know what Analogman chose to do in his version but it's worth checking. I might check it too in a few days. Thanks for the info.

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  13. Well, I've checked this sample and the restyled Analogman Astrotone sounds absolutely incredible, full but clear (for how much a youtube demo can be trusted, of course...).

    http://www.youtube.com/watch?v=D9jtYcOs5ec

    Does yours sounds similar to this?

    Here's a great thread where everything is treated quite extensively:
    http://www.freestompboxes.org/viewtopic.php?f=19&t=2181&sid=d704d51beb6c6f0b3f85be28b86ef79c

    Let me know what you think about that :)

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  14. Well actually the reason I built the AstroTone in the first place was because of I heard the band "Sweet Smoke" and I talked with their guitarist about their fantastic live show from 1974 and he mentioned that he used his Les Paul with the Sam Ash Fuzz Box. When you hear the album it's a really great sounding guitar. Then I hear the GearManDude video with the AnalogMan Astro Tone. It sounded like I had to give it a try. The circuit I got was using the values similar to those shown here be IVIark. I used a BC108 for Q1 and a 2N4401 for Q2. And YES it is that good !!!
    Now that I checked the thread I saw that in fact it is only 3 values away from the AnalogMan AtroTone. the in and out caps and the 470R tone res.
    I must give it a try and maybe hook it up with a 3PDT switch so that I could have both variations in the same circuit. I'll post some demos too once it's done.

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  15. The Analogman one seems to have the Q1 BIAS resistor at 1M2 instead of 3M3, too... and of course the larger input and output caps, and the 470R tone resistor.

    Anyway, let us know something once you've tried this alternate version! :)

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  16. OK....it's very late at night and I have just finished comparing the the 2 modes with the Gearmandude video.
    I only changed the 2 caps and the 1k8 res because my original circuit already had a 1M as the bias for Q1 and not the 3M3.
    I always thought of the circuit as balanced but when I switched to the AM mod I got loads of low end and it seemed much fuller. The TONE knob seems to be very effective at getting from a very bass heavy sound to very thin sound. Switching between the 2 modes almost seems like having the TONE knob rotating two full circles. The AM mod TONE at max is like the original TONE at min.
    Anyway it sounds good. I left the switch to have both versions in the same pedal. Tomorrow I'll drill another hole for it.
    The analogman version did sound a bit brighter than mine but that could have been the amp or the guitar. I am playing an ES-335 with PAF 57 humbuckies. Also the NPN trannies might make some difference, but overall it sounds good. This pedal is not your regular over-the-top fuzz. It's like a mix between a distortion and a mild fuzz. it's good for musical solos where you play a lot of melodies and less for chunky riffs.
    i'll post some clips once I get the box closed to get rid of the interference I have with the box open.

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  17. Great, Doron!!

    So you're confirming that the 470 ohm tone resistor increases the tone knob's efficiency.

    I was thinking to a layout that includes a toggle switch (DPDT?) that would allow to select between the standard input and output caps and the increased couple of the Analogman one - this should absolutely maximize the tone range and make the fuzz able to fit perfectly on both clear and dark amps and guitars.

    About the sound... following your description, it's exactly what I'm looking for: a warm, round hybrid between fuzz and distortion, perfect for blues and hard blues.

    I haven't so much time to elaborate a layout with the added switch until the half of december, but as soon as I can I will give my reading on this!

    Cheers!

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    1. Hi again,

      So I got a 3 pole switch so that I can add in parallel all 3 parts so that both cap values are increased to 470nF (47nF+420nF) and the resistor is decreased from 1k8 to 470R (1k8*640R)/(1k8+640R).

      It works but I don't know if I like it. Now I feel that the original values make the sound too thin while the AM mod make it too fat.
      One thing I gotta say, the TONE knob is super effective going from very fat to very thin and that is super. Rolling off the guitar volume sounds great.
      Here's a little demo of a few licks: in all of them my clean sound goes first, then the AstroTone original, then the AM mod is switched.
      On all licks the setting is - MIM telecaster-AstroTone(Vol 13:00, Attack 12:30, Tone 12:00)-soundcard-Amp simulation.

      https://dl.dropbox.com/u/57241156/DIY%20demos/AstroTone%20demo.mp3

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    2. I agree with you, the standard Astrofuzz is a bit harsh and sharp while the Analogman version seems to be somewhat muddy... messin' with the Tone knob can't be helpful in any way?

      Well I've adapted the above layout with 1M2 BIAS resistors, 470ohm on tone and a DPDT switch which could select between the stock input/output couple of capacitors and the higher values: briefly, the layout is based on Analogman Astrotone values with the addition of a bass cut switch, which should offer a wider tonal range.

      I haven't linked it yet just because I want to check it a pair of times again before, but I think I will post the layout in the next days.

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    3. Here's the improved layout; I've checked it many times and seems correct, but more eyes is better.
      Hope to verify it as soon as possible, in the meantime I hope to receive some impression:

      http://s1325.beta.photobucket.com/user/Blues1911/media/AstrotoneFuzz.png.html

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    4. Nice one Andrea. I'm out so haven't got an opportunity to look it through at the moment but I'm sure someone will give it a check

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    5. Thanks again for your kind attention... so I wait for your impressions ;)

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  18. Quick question, could I use a resistor in front of a germanium diode to reduce the amount of clipping on the signal? And also, which cap is the output cap, I want to wire it to a switch with a higher value cap for an added bass mode.

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    1. You should probably play around with the ones at Attack 2 (input cap) and Volume 3 (output cap). Generally, the input cap is more crucial to up - more bass gets in. 47n in this one shouldn't cut it too much, so input cap could be better option..
      +m

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  19. Anyone else get a lot of white noise when you run the astrotone INTO any other od/dist/fuzz?

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  20. So I was Socketing different transistors to see if I could fix this white noise problem. Different transistors had no effect on the problem. But a new problem has come up. All of sudden, the circuit has stopped working entirely. I get a bypass signal, but that's it. Could something have fried while socketing transistors? I recheckd the entire circuits, no wire breaks or anything. I even reflowed all solder connections. Nothing! Should I try replacing the diodes??

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    1. Ok, so I replaced the diodes. Still nothing. WTF?!

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    2. Whoa, okay. I just kept resoldering over and over and now it's working again. So weird. Anyway, still makes white noise when I run it into another od/dist/fuzz....

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  21. Built this today because it was the only thing I had parts for today!
    Great little layout.

    I've built it in the past but this time I increased the input and output caps to .18uf and this thickened it up a bit. You can still dial it back to '60s style buzz with the tone knob.
    Great 3D fuzzrite quality when hit with a boosted signal, nice bit of crunch by itself.
    Gotta try it on the big amp at practice next week.

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  22. I am constantly surprised at the fact that although this little beast doesn't sound exciting at my home studio, it sounds great and very sweet at higher volumes in band rehearsals. The tone is very effective once I increased the in and out caps. Boosting with any boost serves it well.

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  23. So nobody has any problems with noise?

    My build sounds fantastic. My favorite OD/FUZZ i've ever built. But it adds a good deal of white noise, even at VERY low gain settings.

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    1. I didn't get considerable noise with this circuit. Maybe you have a leaky cap somewhere. Does it still have noise with the TONE knob all the way down?

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    2. Okay, I just rebuilt this using all new parts. New vero, pots, jacks, 3pdt, and components. Same thing. It sounds fantastic, but plenty of white noise is added. WTF?

      Can someone do me a favor? If you build this thing, with your GUITAR volume knob all the way down, turn up your amp to "gig" volume. Now engage the pedal and set it to unity. Do you hear a good amount of white noise? If not, I must be doing something wrong...

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    3. I find at "bedroom" levels, I dont really hear the white noise. Its only at "gig" volume that I the white noise becomes very obvious.

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  24. Just built this and appears to be working fine. Is it correct that when the attack is all the way down that you get no sound. Sorry for being a bit thick!

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    1. Your guitar volume knob should be all the way up and skightly lowered to get that semi clean spanky sparkly tone. When the guitar volume is all the way down you can get white noise with a lot of fuzz designs, as far as I know.

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  25. hey all, just built one with a BC108 (200h) and a BC109 (410h) and it sounds about like the others, def has some hiss to it . big thing i noticed is a lack of output level. doesnt really boost volume at all , even when maxed out. anyone else have this issue? or is there a way to get some more juice out of this thing? definitely is a different beast when playing live through a cranked amp. at home it's just so-so.

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  26. Hey everyone!
    Built it and I love it. I'd like to add a boost to it but was wondering if I could do it without adding a boost circuit at the end of it ? Like put a different resistor on a footswitch instead of one that's already before one of the transistor or something ?
    Thaaaaaanks!

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  27. If I'm not mistaken the tone pot is wired backwards in the layout

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  28. Ok so I just built this monster.
    A couple of things I have to share:
    - Tried several NPN trannies in different positions. Ended up using 2N4401 (400hFe) for Q1, BC108B (230hFe)for Q2. Sounds the best!
    - used a DPDT to switch clipping diodes. Also tried a bunch from Si to Ge. Winning couple is 1N4148 and BAT41.
    If you get the chance, please try these transistors and diodes. I am confindent you will be VERY pleased! :D

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  29. Andrea, I couldn't access the jpeg of your adaptation of the Astrotone with the switch for a bass cut. Could you post that again? How did it sound?

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