Some (Catalinbread) Fuzzrite info for y'all

[Halkbi]

I've loved the sound of the Mosrite Fuzzrite since I first heard The Stooges' debut album in my teens. I've built a couple clones over the years and played a bit with the circuit producing various results (the sound of these things will change radically depending on transistor choice alone) but it never seemed to be quite right. I've never come across Fuzzrite bias voltage discussions and being european it never seemed likely to stumble upon an original to use as a reference. The next best thing which is readily available (yet a bit overpriced for a DIY:er) is the Catalinbread Fuzzrite. After first doing their own twist on the Fuzzrite in the form of the Merkin, Catalinbread worked with the Moseley family who gave them access to a bunch of NOS reference units to help them create what could be considered an official reissue of the silicon Fuzzrite. Go watch their YouTube videos on the topic in case you haven't. Now lets take a look at the circuit.



The Fuzzrite is a strange thing. The depth knob isn't your standard gain control. Instead it blends between the output of the first and second transistor stage (much in the same way that the FY-2 does). The high value of the depth pot gives great variety across the sweep but it also makes it so that the volume varies along with it; the output decreases when going towards the middle of the sweep due to the added resistance at the output of both transistor stages. Getting unity level anywhere between the two extremes may prove difficult for a heavy handed player and it's not uncommon for clones to have an added gain recovery stage to adress this issue (the Merkin being one example). What's rarely mentioned is that an octave up effect can be achieved as the depth pot is increased. In my testing, lower gains of around 40 makes it very pronounced and gains of 120+ makes it more subtle. Another point of confusion is the 22k to ground from the output cap of Q2 which creates a high pass filter just under 3.3kHz on the output of Q2. As it was originally soldered between the pots and not on the board, it's missing in a lot of schematics (including the one at Fuzzcentral) and there has been much debate on whether or not all units had it. It's also popular to make it switchable in and out of circuit. The non-standard pot values are also a point of discussion with a some claiming it's essential to get as close to them as possible and some dismissing it and going for 500k/50k pots instead.

I've missed out on a bunch of used Catalinbread Fuzzrites in the last year, but this week I got lucky and yesterday it was waiting in the mail. It definitely has a different flavour to what I've been able to achieve in my own builds and I was curious to see how Catalinbread tuned their circuit to match the original. Took it apart to inspect the board as I'd never come across any gutshots of it.



What we have is essentially a 1:1 copy of the original circuit with added polarity protection and LED circuitry. Cap values are 50n for the input caps and 2.2n for the output caps. No power filtering on mine although there are solder pads and markings for an electrolytic cap between 9v+ and ground under one of the pots. The 22k is in place as expected. However, it does deviate from whats typically seen in the schematics in one place: the volume pot value has been increased from 50k to 500k. I was initially surprised on how much low end it retained with the depth knob set fully CCW as well as how much volume it had on tap and this might be the reason why. It may be that most original Fuzzrites actually had 500k volume pots.



Looking at the trannies, it seems like we got a pair of NOS (Sanken?) 2SC2316 at hand. Anyone know the typical gains of such devices? I grabbed my multimeter to check voltages and I was a bit surprised of my findings. Collectors are about 0.52v and bases around 0.47v (with the emitters to ground giving 0v, battery measured at 8.95v). Seems a bit low to me but then again I've never seen any voltages mentioned for the Fuzzrite and as stated, it's a weird animal. I haven't had the chance to try it side by side with any of my clones or into a proper rig, but based upon my recollection on how mine performed I can tell that this is quite different and it seems to absolutely nail the lead tone of I Wanna Be Your Dog. Well done Catalinbread! Hope this info is of use for anyone out there 

[PRR]

The voltages and the betas are known by inspection. Look at the biasing. Same 470k value from B+ to C and from C to B. But the currents are in ratio of beta. So 0.52V-0.47V= 0.050V on Rcb and 8.28V on Rc. Obviously unless beta is near unity the collectors must sit very low. Beta seems to be 169 at 18uA.

[iainpunk]

i build my fuzzrite with NOS BC107 transistors i had laying around with great success!
its not exactly that ''i wanna be your dog'' intro tone, but it came close enough that it sounded right if you don't listen to it back to back with the record. the only fuzz i regret taking out of its enclosure for re-use of the enclosure for another fuzz project.

cheers

[mc50]

When was your Catalinbread Fuzzrite made? I know that company has had some issues, with the core employees leaving after being involved in some kind of legal battle with the new owner, and for a while there's been talk of quality control issues. Yours looks well-made.

So we think the 2SC2316 transistors are ~170 hFE? I guess they must be some kind of magic NOS then, most spec sheets I could pull up give a min hFE of 500:

https://alltransistors.com/adv/pdfdatasheet_sanken-ele/2sc2315_2sc2316.pdf
https://alltransistors.com/adv/pdfdatasheet_inchange_semiconductor/2sc2316.pdf

[mc50]

FWIW, the usual places on the Internets produce some results when searching for 2SC2316Y, which almost look like your transistors. I've not been able to find more than:

"Type Designator: 2SC2316Y

Material of Transistor: Si

Polarity: NPN

Maximum Collector Power Dissipation (Pc): 0.9 W

Maximum Collector-Base Voltage |Vcb|: 120 V

Maximum Collector-Emitter Voltage |Vce|: 120 V

Maximum Emitter-Base Voltage |Veb|: 5 V

Maximum Collector Current |Ic max|: 0.8 A

Max. Operating Junction Temperature (Tj): 150 °C

Transition Frequency (ft): 120 MHz

Collector Capacitance (Cc): 30 pF

Forward Current Transfer Ratio (hFE), MIN: 120

Noise Figure, dB: -

Package: TO92"

120 min would, I suppose, allow for our deduced 169.

[wjmwpg]

Many thanks for this - very interesting. When I decided to start building my first fuzz (way back in December), my number one priority/sonic reference was No Fun off the same album. I actually started with an FY2 schematic and started experimenting/modding from there. I'm now happy to say that I've created something that, for me at least, is that and maybe more. It's been a blast. Now I just have to house this beast! 

[duck_arse]

detail from the OP's second photo:

"Type Designator: 2SC2316Y
......
Forward Current Transfer Ratio (hFE), MIN: 120"

seems reasonable.

this just in, includes the corrct case type number and "hFE Classification" -

http://pdf.datasheetcatalog.com/datasheet2/a/0aziu33a0oqu7heqy4z2podp56wy.pdf

[mc50]

When I decided to start building my first fuzz (way back in December), my number one priority/sonic reference was No Fun off the same album. I actually started with an FY2 schematic and started experimenting/modding from there. I'm now happy to say that I've created something that, for me at least, is that and maybe more.

Interesting you should say that. I own a Fairfield Circuitry "An Unpleasant Surprise" pedal, which to my ears has started life as an FY2, and by playing with the toggles I get both a "Frusciante in the La Cigale intro" tone, and the "I Wanna Be Your Dog" tone pretty convincingly (with a Stratocaster, bridge pickup).

I don't know for sure what the "Unpleasant Surprise" is based on exactly, but I'd be surprised if there's not any FY2 influence there at all. As always, I could be wrong.

[nocentelli]

I don't know for sure what the "Unpleasant Surprise" is based on exactly.....

It's a TLO72 dual opamp being tortured by 2 x J201 JFETs boosting the input signal and some weird biasing arrangement. Schematic is here - http://www.pedalpcb.com/docs/CalamityFuzz.pdf

[mc50]

Oh man, they've traced it already? I feel sorry for Fairfield Circuitry on this, they're very decent people making great stuff and I think they deserve the purchase...

In any case, if you squint it kind of looks like an FY2 with the opamp part between Q2 and Q3, so I wasn't, I think, that far off: http://pedalparts.co.uk/docs/fy2.pdf

[nocentelli]

Oh man, they've traced it already? I feel sorry for Fairfield Circuitry on this, they're very decent people making great stuff and I think they deserve the purchase...

It's been on sale for nearly a decade, so it's actually taken a quite a while. I do agree that Fairfield are decent people and deserve to sell pedals, but I'm not totally convinced many sales are lost through people choosing to DIY rather than buy.

[John Lyons]

For what it's worth.

Here's what David at DAM who did a lot of research into this has to say:

"Thanks to a trip to London a visit to a Soho's Original Bookshop and the discovery of Robert Matheu's outstanding book on the Stooges I think it maybe wise to dispel the "Ron used a Fuzzrite" myth once and for all, that is until someone shows me a picture of Ron actually using one. Robert's fine book has several fine shots that clearly show Ron actually using a Vox Tone Bender. Other photographic material that can be sourced on the internets show Ron with what appears to be a Marshall Supa Fuzz. Either way, it ain't no Fuzzrite. In a nutshell and in my head at least. Dig the early Stooges fuzz tone? Get high, get a Vox. Simple."

[mc50]

Forgot to ask previously, do we know that both transistors in Catalinbread's pedal are the same / have the same markings / measured the same? Only one transistor is clearly visible in the initial post.

I think it's implied that they're identical, but I've found conflicting wisdom on various forums as to what Q1 and Q2's hFE should be, and very rarely do people recomend the same hFE for both (with some claiming their recommendations are based on measuring vintage units).

I'm asking because I've built one (with sockets) and am curious to know when I've hit upon Catalinbread's secret sauce (I think I recall R.G. Keen stating somewhere on this forum that Si devices are remarkably similar so part numbers would mean much less than identical hFEs).

[mc50]

For what it's worth.

Here's what David at DAM who did a lot of research into this has to say:

"Thanks to a trip to London a visit to a Soho's Original Bookshop and the discovery of Robert Matheu's outstanding book on the Stooges I think it maybe wise to dispel the "Ron used a Fuzzrite" myth once and for all, that is until someone shows me a picture of Ron actually using one. Robert's fine book has several fine shots that clearly show Ron actually using a Vox Tone Bender. Other photographic material that can be sourced on the internets show Ron with what appears to be a Marshall Supa Fuzz. Either way, it ain't no Fuzzrite. In a nutshell and in my head at least. Dig the early Stooges fuzz tone? Get high, get a Vox. Simple."

Thanks!

Saw that a while back, but thought "there's how they got that tone, and here's how I can get that tone". Meaning that putting a Tonebender through a Marshall might sound like a Fuzzrite through my tweed Fender, or that there was a studio engineer that had a full-on mixer / console which they might have used to cut bass, or put a mic at a weird angle on a speaker that they've put chewing gum on.

Long story, short, I still think for most people a Fuzzrite is a quicker way to that early Stooges tone, and I say this as someone who's built both a Fuzzrite and a VOX Tonebender MkII chasing it.

[garcho]

Trying to "get tone" from a record with a guitar pedal is Quixotic at best. Are you going to play a gig through the same guitar, same amp, same strings, same pick, a mic, pre, console, a bunch of mastering gear, a vinyl lathe, your stereo amd your speakers? If not, don't worry about that pedal too much.

[Halkbi]

For what it's worth.

Here's what David at DAM who did a lot of research into this has to say:

"Thanks to a trip to London a visit to a Soho's Original Bookshop and the discovery of Robert Matheu's outstanding book on the Stooges I think it maybe wise to dispel the "Ron used a Fuzzrite" myth once and for all, that is until someone shows me a picture of Ron actually using one. Robert's fine book has several fine shots that clearly show Ron actually using a Vox Tone Bender. Other photographic material that can be sourced on the internets show Ron with what appears to be a Marshall Supa Fuzz. Either way, it ain't no Fuzzrite. In a nutshell and in my head at least. Dig the early Stooges fuzz tone? Get high, get a Vox. Simple."

Without disrespect to either you or DAM, the I think it's fair to say that fuzz sound of the first Stooges album is a Fuzzrite. I've spent an unhealthy amount of time looking at pictures trying to dissect Ron's rig and while it is correct that he's was never caught on photo using a Fuzzrite, that doesn't rule out that it was used in the studio. Comparing the tones on the record to different breeds of Fuzzrites leaves me with no doubt that that's what we're hearing. I Wanna Be Your Dog is a Fuzzrite running on full blast (rhythm parts played on the bridge pickup and the main solo played on the neck pickup) and the rhythm tone of No Fun can be found on the first quarter of the depth knob. It's a VERY peculiar sound and I doubt that any Tonebender could get the same vibe. Who knows why he didn't seem to ever use the Fuzzrite live; it may have been sitting around in the studio or was brought to the sessions by John Cale. My speculation is that the Vox Tonebender was used on Funhouse, whose guitar tone is very different (and certainly has that treble boosted Marshall vibe that a Vox Tonebender is very capable of delivering). Heck, for the sake of speculation I might mention that Deniz Tek has stated that Ron also used a Fuzzface early on (but I have a hard time thinking that that was ever used in the studio).

Forgot to ask previously, do we know that both transistors in Catalinbread's pedal are the same / have the same markings / measured the same? Only one transistor is clearly visible in the initial post.

I think it's implied that they're identical, but I've found conflicting wisdom on various forums as to what Q1 and Q2's hFE should be, and very rarely do people recomend the same hFE for both (with some claiming their recommendations are based on measuring vintage units).

I'm asking because I've built one (with sockets) and am curious to know when I've hit upon Catalinbread's secret sauce (I think I recall R.G. Keen stating somewhere on this forum that Si devices are remarkably similar so part numbers would mean much less than identical hFEs).

Trannies are identical, as are bias voltages. Q2 measured just slightly higher (within two hundreds of a volt if memory serves me correct, seemed too little of a difference to note in my original post), which implies that their gain should be somewhat matched (which indeed differs from the general opinion of what the ultimate Fuzzrite should consist of).

[mc50]

Trannies are identical, as are bias voltages. Q2 measured just slightly higher (within two hundreds of a volt if memory serves me correct, seemed too little of a difference to note in my original post), which implies that their gain should be somewhat matched (which indeed differs from the general opinion of what the ultimate Fuzzrite should consist of).

Thanks! Much appreciated.

[kikey]

Here is a gutshot on my CatalinBread Fuzzrite.
PCB is marked: FUZZrite Catalinbread 2015, P60435

Quite a few differences compared to the shots posted earlier.
- Volume Pot B250K
- Depth Pot C500K
- Q1: C2316
- Q2: KSP 42 -D11  (https://datasheetspdf.com/pdf/252838/FairchildSemiconductor/KSP42/1)

The pedal sounds really good.
Fuzzrites seems not to be an exact science 

[mc50]

The pedal sounds really good.
Fuzzrites seems not to be an exact science 

Definitely. FWIW, based on the info gleaned from the original post I've put BC639 in both positions in my socketed Si Fuzzrite (measured at 172 hFE) and for all I can tell based on demos (I don't own a Catalinbread / Moseley pedal) it appears to sound very similar.

My previous choice (~200 hFE / ~90 hFE) also sounded very good in a different way.

Yep, Fuzzrites are tricky. Also quite a lot of fun. And pretty easy to build.