Fuzz Face build, trannies and caps...

[gbkd80]

I have a bunch of NOS parts that I got from a flea market and decided to etch out a standard Arbiter FF board.  In the piles of parts I have a box of axial capacitors and some Sanyo 2SB187 ge trannies.

IF the trannies measure out ok, I'd like to try them in the circuit.  Has anyone had any experience using these in a FF before? 

The other question is would it matter if I used a porcelain 0.01uf cap in place of the metallized film?  Any noticeable audio difference?

[vigilante397]

Sanyo 2SB187 ge trannies.

Mind the pinout as they're backwards from AC128's, but they should work. If you're unsure about which pin is which, socket them so you can switch them around just in case.

The other question is would it matter if I used a porcelain 0.01uf cap in place of the metallized film?  Any noticeable audio difference?

By porcelain do you mean ceramic? In most cases there shouldn't be any noticeable audio difference, but under certain circumstances they have been known to go microphonic (compare construction of a ceramic disc capacitor to the construction of a condenser microphone), which can be a bit messy. So avoid it when possible (or convenient) and it should be fine. They aren't widely recommended for audio quality but the stompbox police won't bust down your door and stop you.

[gbkd80]

By porcelain do you mean ceramic?

Nope.  I got a box of vintage Argonne porcelain tubular capacitors with my "pile o' goodies". 

http://www.ebay.com/itm/Vintage-NOS-Argonne-Porcelain-Cased-Capacitor-01-uf-600v-Guitar-Amp-Tone-Cap-/111778801564?


According to this listing, they are extremely rare.  I don't know if that's a true statement or not, I've obviously never heard of them but they're NOS and I got a good amount of them in the original box, so...

I guess I'm just wondering if I'll hear any audible difference between something other than (not ceramic) the typical metallized film or tropical fish cap, keeping with the same values...  And then again, they could all be bad 

Mind the pinout as they're backwards from AC128's, but they should work. If you're unsure about which pin is which, socket them so you can switch them around just in case.

I almost planned on socketing everything to use this as a test unit, but I'll probably just put everything in place and definitely socket the trannies. 

[Cozybuilder]

3 words:
Breadboard, breadboard, breadboard.

[PRR]

> vintage Argonne porcelain tubular capacitors .... According to this listing, they are extremely rare.

This is ordinary stuff sold by Lafayette Radio back in the 1960s.

Some guy near Milwaukee stocked-up decades ago, apparently didn't use them (though the leads do look played-with), then died and his daughter cleared-out the workshop. (I don't know that, but it happens a lot; will happen to me too.)

They are true foil caps. They may be dipped in dinner-ware clay and baked ("porcelain"); or inserted in baked-clay shells. Slight benefit when used in a hot (vacuum-tube) chassis. Also 600V! No benefit for cool 9V stomps, and you could buy a smaller 0.01u cap, but if you got it use it.

99% chance they are fine for all audio purposes. I would put the Ohm-meter on and check that the resistance goes to infinity (not shorted from old age).

[gbkd80]

This is ordinary stuff sold by Lafayette Radio back in the 1960s.

Heh.. yeah, I read that somewhere else when I was doing a deep search today. 

It was still cool; I got 5 of those metal card catalog cabinets (2 drawers per) stocked with all kinds of carbon comp resistors, caps, diodes, germanium transistors, switches, knobs... even brand new rolls of solder and a tape head demag... And that's just the big stuff.  There were all kinds of doodads in this bundle.  Got it for 40 bucks... I'm sure I can make use of some of the stuff.

[hymenoptera]

Sounds like a killer deal on some fun stuff. I'm sure everyone would be drooling if there were pics to go along with the thread

[duck_arse]

show me a pic of the caps in their box, and I'll drool some.

[gbkd80]

show me a pic of the caps in their box, and I'll drool some.

[PRR]

A near-complete Full Set in-box *is* a find.

By now, I see it more as shop decoration than "supplies". 600V caps are way bigger than most small-audio needs, especially pedals.

[hymenoptera]

They're beautiful.

If you don't find a use for them, you could always sell then on ebay for $9 a piece lol 

[Cozybuilder]

This is the kind of thing you could do a turret board layout with and use a clear box

[duck_arse]

that is indeed something. I was expecting a really crappy tattered box, not like that.

at 9$ a piece, you'd have to mangle all the leads first (NOS, unused, indeed). that box could totally wreck the market.

New!

[Guitar Poppa]

I have a box of axial capacitors and some Sanyo 2SB187 ge trannies (...) Has anyone had any experience using these in a FF before ? 

The other question is would it matter if I used a porcelain 0.01uf cap in place of the metallized film?

Hello,

>>>> I've never used the 2SB187 in Fuzz Face, but I just now read the data sheet... They should be perfectly Ok for it. Just a remark : Their minimal gain is said to be 100. You shoud measure a lot of trannies in your box, and select models with gain about 80 to 120 if you want to build a classic FF. If you want a more heary sound, select 120 to 200.
Not more if you want to keep the traditionnal resistor values.
Like every time with germanium, the real problem his the leakage current. It is not drastic for the second transistor, even high leakage currents, up to 500µA may be acceptable. (just use the classical 10 kiloohm trimpot in place of the 8k2 resistor).
The firts transistor should not have a leakage current higher than 200µA. If higher, the biasing will be difficult or impossible.
Generaly, Japanese transistors have less leakage than european ones. I hope you'll find what you need. But don't try to get as low leakage as possible : A little bit is good for compression by the firts transistor, and more on the second transistors is generaly a good deal.

>>>> On the caps...
I have built many preamplifiers, HiFi and PA devices... I have often read and more often listend that ceramic caps are NOT GOOD for sound quality. They bring distorsion, and some erratic phase shifts at audio frequencies. They've been designed for high frequency, not for audio. Any metalized film will be much better and will respect the granularity of your fuzz. Notice that I don't speak of esoteric componants : just normal ones, but made for audio. Orange drop or tropical fish are quite good and similar.

Tell me about your fuzz when y'ou'll have buit it !
Guitar Poppa

If you want se something be me :
http://guitarpoppa.com/?p=389
http://guitarpoppa.com/?p=864

[LightSoundGeometry]

I have a 0c77 and the peak atlas says its currant leakage is .64 ..I am assuming it is leaking 640 microamps? so is this transistor useless or will it work as a q2-q3 someplace ?

I need a definitive answer ..geoflex says anythign over 300 is bad but I read everywhere else all sorts of answer ..a guy on here last time said the 500 uF was a good transistor ..which is it ..is it good or bad and what is the cut off line..I am going with geoflex on this but you never know because I keep reading different things

[Guitar Poppa]

Hello,

Your questions are urgent and necessary, but they require answers that, to be definitive, can not be simple. The analog electronics is a technique that seeks to achieve precise devices with inaccurate components. The problems are multiplied when it comes to use germanium transistors, that are particularly diverse and changing in the same type.

So you use a peak tester, and so do I, but not only. I also use testers who are very close to those RG Keen and Small Bear use on their side. Generally, the measures are not exactly equivalent, but are convergent, and indicate specific levels of quality.

With a 600 to 700µA leakage, your transistor is leaky indeed.
For sure too much to be used in first Fuzz face transistor.
Could be possible as 2d transistor, which nead leaks to give a more compressed and soften sound (Engineers would tell about Millers's currents), but has to be tested in real conditions.
Such a leaky tranny could correctly find its place as preamplifier in the 3 transistors fuzzes, like Tone Bender 2 or SupaFuzz. (and even more leaky ones, sometimes up to 900µA).

But before interpreting leakage measure, you must know temperature at which measurement was made: a transistor that had time to take the temperature of an air conditioned room ? Which was held between fingers for more than 10 seconds? Out of storage in the sun? Between these three situations, there is at least 30% of variations of the leakage current. This is the first thing to know.
Personally, I do my measures after taking the component thirty seconds between my fingers. It is then a stable temperature, and it's pretty much the temperature it will actually support in my equipment when I'll play in a club or bar.

To resume, according to a classical Fuzz Face :

First transistor : leakage < 200µA at ambiant temperature ; < 400µA when between the fingers. (can be useful to lower the 33k resitor to 27k or 22k).
When very low leakage (<100µA), the sound will be less creamy, more close to silicon sound...

Second transistor : leakage < 600µA at ambiant temperature ; <900µA when between the fingers (use a 10k trimpot in place of th 8k2 resistor, which is often over scaled).
Sonicaly no interest to use a transistor with leakage less than 400µA : the sound will loose dynamic compression and filtering due to Miller's currents which are "good defects" !

I told it was not so simple. This advices are built on long experience : 10 years buying and testing trannies especially from europe and USSR, and building stomboxes based of that magical but characterial Fuzz Face circuitry.
Happy to give a hand !

For some other informations : http://guitarpoppa.com/?p=2071

[LightSoundGeometry]

hey thanks for answering , appreciate it. i was on the iphone so I am glad you got the jist of what I was asking lol

I let them relax on the peak for about 1-2 hours at my room temperature which is probably someplace between 73-80 F

the OC77 I let out all day and fired it up after about 8 hours of setting on the peak clips, untouched, room temp. ..read .51mA so its leaking a good 500uA for sure ..Beta is 107 , collector current is 2.5mA Voltage drop across Vbe is .33 volts and test current Ib is 5.11mA

so basically it has a place , but you have to socket/BB the circuit and give her a test. this helps for sure. at least a starting point is made; and no time wasted trying to put this in a RM for example.

[PRR]

> ceramic caps are NOT GOOD for sound quality. They bring distorsion, and some erratic phase shifts

Notice that the "porcelain" caps in the image in reply #2 are (probably) *not* Ceramic Caps we see today. They are very likely paper/wax caps in porcelain shells. An odd historical find.

Ceramic caps 1,000pFd and below are usually very-very good for any purpose. But <1000p caps have few uses in audio (treble-boost, supersonic filters).

Ceramic much over 1,000pFd has been "salted" with strange chemicals to increase the capacitance. In small doses this may be OK for some audio purposes. However I can hear the odd sound of a 0.01uFd (10,000pFd) ceramic cap inside a phono preamp.

[Guitar Poppa]

Hello PRR !

Many thanks for your precisions. I totally agree with them.

When I wrote bad things about ceramic caps, I was not thinking of little capacitances, especially under 1000pf. Like everybody, I commonly use them for ultrasonic stabilization and other feedbacks... My warnings concerned 1000pf and more caps, used in preamps, effects circuits etc, where MKT or MKP caps are much better.

But...
I think silver-mica caps are the best in tube Tone controls in guitar amps : very clear and dynamic as treble filter.

Another word : Did you ear the quality of military russian paper/oil capacitors. When used as coupling capacitors in tube amps, especially on input stage or between pahse shifter and push pull, they bring a very pleasant transparency. Too bad they are too huge to fit in a stompbox !

happy to communicate on this site !

[duck_arse]

a little off topic, but your posts read a bit like poetry, poppa. in a good way, though. that's a nice site you have, too.

now, back to the topic .....